S-3ASR

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TABLE OF CONTENTS

As filed with the Securities and Exchange Commission on January 13, 2010

Registration No. 333-            

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

Form S-3
REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933

MARKWEST ENERGY PARTNERS, L.P.
MARKWEST ENERGY FINANCE CORP.*
(Exact name of registrant as specified in its charter)

Delaware
Delaware
(State or other jurisdiction of incorporation or organization) 27-0005456
20-1805917
(I.R.S. Employer Identification No.)

1515 Arapahoe Street
Tower 2, Suite 700
Denver, Colorado 80202
(303) 925-9200
(Address, including zip code, and telephone number, including area code, of registrant's principal executive offices)

Nancy K. Buese
1515 Arapahoe Street
Tower 2, Suite 700
Denver, Colorado 80202
(303) 925-9200
(Name, address, including zip code, and telephone number, including area code, of agent for service)

Copy to:
David P. Oelman
Vinson & Elkins L.L.P.
First City Tower
1001 Fannin Street, Suite 2500
Houston, Texas 77002-6760
(713) 758-2222

Approximate date of commencement of proposed sale to the public: From time to time after this Registration Statement becomes effective.

           If the only securities being registered on this Form are being offered pursuant to dividend or interest reinvestment plans, please check the following box.    o

           If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, other than securities offered only in connection with dividend or interest reinvestment plans, check the following box.    ý

           If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.    o

           If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.    o

           If this Form is a registration statement pursuant to General Instruction I.D. or a post-effective amendment thereto that shall become effective upon filing with the Commission pursuant to Rule 462(e) under the Securities Act, check the following box.    ý

           If this Form is a post-effective amendment to a registration statement filed pursuant to General Instruction I.D. filed to register additional securities or additional classes of securities pursuant to Rule 413(b) under the Securities Act, check the following box.    o

           Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of "large accelerated filer," "accelerated filer" and "smaller reporting company" in Rule 12b-2 of the Exchange Act.

Large accelerated filer ý Accelerated filer o Non-accelerated filer o
(Do not check if a smaller reporting company) Smaller reporting company o

CALCULATION OF REGISTRATION FEE

Title of each class of securities to be registered		Amount to be registered/proposed maximum offering price per unit/ proposed maximum offering price(1)	Amount of registration fee
Debt Securities
Common Units
Guarantees of Debt Securities
	Total	(1)	(1)

(1)

An indeterminate aggregate initial offering price or number of the securities of each identified class is being registered as may from time to time be offered hereunder at indeterminate prices. In accordance with Rules 456(b) and 457(r) under the Securities Act of 1933, the registrant is deferring payment of all of the registration fee and will pay the registration fee subsequently in advance or on a pay-as-you-go basis.

        *  The following are co-registrants that may guarantee the debt securities:

MarkWest Energy Operating Company, L.L.C. (Exact Name of Registrant As Specified In Its Charter)
Delaware	27-0005448
(State or Other Jurisdiction of Incorporation or Organization)	(I.R.S. Employer Identification Number)
West Shore Processing Company, L.L.C. (Exact Name of Registrant As Specified In Its Charter)
Michigan	76-0501616
(State or Other Jurisdiction of Incorporation or Organization)	(I.R.S. Employer Identification Number)
MarkWest Energy Appalachia, L.L.C. (Exact Name of Registrant As Specified In Its Charter)
Delaware	47-0852385
(State or Other Jurisdiction of Incorporation or Organization)	(I.R.S. Employer Identification Number)
Mason Pipeline Limited Liability Company (Exact Name of Registrant As Specified In Its Charter)
Michigan	26-2664116
(State or Other Jurisdiction of Incorporation or Organization)	(I.R.S. Employer Identification Number)
MarkWest Michigan Pipeline Company, L.L.C. (Exact Name of Registrant As Specified In Its Charter)
Michigan	83-0375568
(State or Other Jurisdiction of Incorporation or Organization)	(I.R.S. Employer Identification Number)
MarkWest Oklahoma Gas Company, L.L.C. (Exact Name of Registrant As Specified In Its Charter)
Oklahoma	86-1089780
(State or Other Jurisdiction of Incorporation or Organization)	(I.R.S. Employer Identification Number)
MarkWest New Mexico, L.L.C. (Exact Name of Registrant As Specified In Its Charter)
Texas	30-0157474
(State or Other Jurisdiction of Incorporation or Organization)	(I.R.S. Employer Identification Number
MarkWest Pinnacle, L.L.C. (Exact Name of Registrant As Specified In Its Charter)
Texas	30-0157461
(State or Other Jurisdiction of Incorporation or Organization)	(I.R.S. Employer Identification Number)
MarkWest PNG Utility, L.L.C. (Exact Name of Registrant As Specified In Its Charter)
Texas	30-0157467
(State or Other Jurisdiction of Incorporation or Organization)	(I.R.S. Employer Identification Number)

MarkWest Texas PNG Utility, L.L.C. (Exact Name of Registrant As Specified In Its Charter)
Texas	30-0157468
(State or Other Jurisdiction of Incorporation or Organization)	(I.R.S. Employer Identification Number)
MarkWest Blackhawk, L.L.C. (Exact Name of Registrant As Specified In Its Charter)
Texas	30-157471
(State or Other Jurisdiction of Incorporation or Organization)	(I.R.S. Employer Identification Number)
MarkWest Power Tex, L.L.C. (Exact Name of Registrant As Specified In Its Charter)
Texas	45-0537840
(State or Other Jurisdiction of Incorporation or Organization)	(I.R.S. Employer Identification Number)
MarkWest Pipeline Company, L.L.C. (Exact Name of Registrant As Specified In Its Charter)
Texas	20-2229672
(State or Other Jurisdiction of Incorporation or Organization)	(I.R.S. Employer Identification Number)
MarkWest Energy East Texas Gas Company, L.L.C. (Exact Name of Registrant As Specified In Its Charter)
Delaware	20-1311706
(State or Other Jurisdiction of Incorporation or Organization)	(I.R.S. Employer Identification Number)
MarkWest Javelina Company, L.L.C. (Exact Name of Registrant As Specified In Its Charter)
Texas	76-0263770
(State or Other Jurisdiction of Incorporation or Organization)	(I.R.S. Employer Identification Number)
MarkWest Javelina Pipeline Company, L.L.C. (Exact Name of Registrant As Specified In Its Charter)
Texas	38-2909338
(State or Other Jurisdiction of Incorporation or Organization)	(I.R.S. Employer Identification Number)
Matrex, L.L.C. (Exact Name of Registrant As Specified In Its Charter)
Michigan	84-1349848
(State or Other Jurisdiction of Incorporation or Organization)	(I.R.S. Employer Identification Number)
MarkWest Liberty Gas Gathering, L.L.C. (Exact Name of Registrant As Specified In Its Charter)
Delaware	26-2368254
(State or Other Jurisdiction of Incorporation or Organization)	(I.R.S. Employer Identification Number)

MarkWest Gas Services, L.L.C. (Exact Name of Registrant As Specified In Its Charter)
Texas	26-1795927
(State or Other Jurisdiction of Incorporation or Organization)	(I.R.S. Employer Identification Number)
MarkWest Energy GP, L.L.C. (Exact Name of Registrant As Specified In Its Charter)
Delaware	01-0636219
(State or Other Jurisdiction of Incorporation or Organization)	(I.R.S. Employer Identification Number)
MarkWest Hydrocarbon, Inc. (Exact Name of Registrant As Specified In Its Charter)
Delaware	84-1352233
(State or Other Jurisdiction of Incorporation or Organization)	(I.R.S. Employer Identification Number)
MarkWest Marketing, L.L.C. (Exact Name of Registrant As Specified In Its Charter)
Delaware	26-2430225
(State or Other Jurisdiction of Incorporation or Organization)	(I.R.S. Employer Identification Number)
MarkWest Gas Marketing, L.L.C. (Exact Name of Registrant As Specified In Its Charter)
Texas	26-2827902
(State or Other Jurisdiction of Incorporation or Organization)	(I.R.S. Employer Identification Number)
MarkWest McAlester, L.L.C. (Exact Name of Registrant As Specified In Its Charter)
Oklahoma	26-3195589
(State or Other Jurisdiction of Incorporation or Organization)	(I.R.S. Employer Identification Number)

PROSPECTUS

MarkWest Energy Partners, L.P.

MarkWest Energy Finance Corp.

Common Units

Debt Securities

        We may from time to time offer the following securities under this prospectus:

•

common units representing limited partner interests in MarkWest Energy Partners, L.P., and

•

debt securities of MarkWest Energy Partners L.P.

        Our common units are traded on the New York Stock Exchange under the symbol "MWE." We will provide information in the prospectus supplement for the trading market, for any debt securities we may offer.

        MarkWest Energy Finance Corp. may act as co-issuer of the debt securities, and all other direct or indirect wholly-owned subsidiaries of MarkWest Energy Partners, L.P. (which we refer to as "Subsidiary Guarantors"), other than "minor" subsidiaries as such item is interpreted in securities regulation governing financial reporting for guarantors, may guarantee the debt securities.

        Each time we sell securities we will provide a prospectus supplement that will contain specific information about the terms of that offering. This prospectus may not be used to consummate sales of securities unless accompanied by a prospectus supplement. The prospectus supplement may also add, update or change information contained in this prospectus. You should read this prospectus and any prospectus supplement carefully before you invest. You should also read the documents we have referred you to in the "Where You Can Find More Information" section of this prospectus for information on us and for our financial statements.

Limited partnerships are inherently different from corporations. You should carefully consider each of the factors described under "Risk Factors," which begin on page 5 of this prospectus before you make an investment in our securities.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of the securities or passed upon the accuracy or adequacy of this prospectus. Any representation to the contrary is a criminal offense.

The date of this prospectus is January 13, 2010

TABLE OF CONTENTS

About This Prospectus	1
Where You Can Find More Information	1
Forward-Looking Statements	3
About MarkWest Energy Partners	4
Risk Factors	5
Use Of Proceeds	6
Ratios Of Earnings To Fixed Charges	6
Description of Common Units	7
Description Of Our Debt Securities	9
Cash Distribution Policy	17
Partnership Agreement	18
Material Tax Consequences	28
Investment in Markwest Energy Partners by Employee Benefit Plans	44
Plan of Distribution	47
Legal Matters	49
Experts	49

        You should rely only on the information contained or incorporated by reference in this prospectus or any prospectus supplement. We have not authorized any other person to provide you with different information. You should not assume that the information incorporated by reference or provided in this prospectus or any prospectus supplement is accurate as of any date other than the date on the front of each document.

ABOUT THIS PROSPECTUS

        This prospectus is part of a registration statement that we and MarkWest Energy Finance Corporation have filed with the Securities and Exchange Commission using a "shelf" registration process. Under this shelf registration process, we may offer from time to time our common units or debt securities described in this prospectus in one or more offerings. Each time we offer securities, we will provide you with a prospectus supplement that will describe, among other things, the specific amounts and prices of the securities being offered and the terms of the offering. The prospectus supplement may also add, update or change information contained in this prospectus. Therefore, before you invest in our securities, you should read this prospectus, any attached prospectus supplements and the additional information described below under "Where You Can Find More Information."

        As used in this prospectus, "we," "us," "our," "the Partnership" and "MarkWest Energy Partners" mean MarkWest Energy Partners, L.P. and, where the context requires, include our operating subsidiaries.

WHERE YOU CAN FIND MORE INFORMATION

        We file annual, quarterly and other reports and other information with the SEC. You may read and copy any document we file with the SEC at the SEC's Public Reference Room at 100 F Street, N.E., Room 1580, Washington, D.C. 20549. Please call the SEC at 1-800-SEC-0330 for further information on the operation of the SEC's Public Reference Room. The SEC maintains an Internet site that contains reports, proxy and information statements and other information regarding issuers that file electronically with the SEC. Our SEC filings are available on the SEC's website at http://www.sec.gov. You also can obtain information about us at the offices of the New York Stock Exchange, 20 Broad Street, New York, New York 10005.

        The SEC allows us to "incorporate by reference" the information we have filed with the SEC. This means that we can disclose important information to you without actually including the specific information in this prospectus by referring you to other documents filed separately with the SEC. The information incorporated by reference is an important part of this prospectus. Information that we later provide to the SEC, and which is deemed to be "filed" with the SEC, will automatically update information previously filed with the SEC, and may replace information in this prospectus and information previously filed with the SEC.

        We incorporate by reference the documents listed below and any future filings we make with the SEC under Section 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934 (excluding any information furnished pursuant to 2.02 or 7.01 on any current report on Form 8-K), including all such documents we may file with the SEC after the date of the initial registration statement and prior to the effectiveness of the registration statement, until all offerings under this registration statement are completed;

•

Our annual report on Form 10-K for the year ended December 31, 2008, as filed with the SEC on March 2, 2009, as modified by our current report on Form 8-K as filed with the SEC on May 18, 2009 for the retrospective applications of changes to generally accepted accounting principles related to the presentation of non-controlling interest and the calculation of earnings per unit (excluding the Starfish Pipeline Company, LLC Consolidated Financial Statements in Part IV, Schedule A thereto);

•

Our quarterly reports on Form 10-Q for the quarter ended March 31, 2009, as filed with the SEC on May 11, 2009, as amended by the amended quarterly report on Form 10-Q/A for the quarter ended March 31, 2009, as filed with the SEC on October 16, 2009, for the quarter ended June 30, 2009, as filed with the SEC on August 10, 2009 and for the quarter ended September 30, 2009, as filed with the SEC on November 9, 2009; and

1

•

Our current reports on Form 8-K as filed with the SEC on January 28, 2009, January 28, 2009, March 4, 2009, March 24, 2009, April 24, 2009, May 7, 2009, May 11, 2009, May 18, 2009, May 27, 2009, June 10, 2009, July 1, 2009, July 24, 2009, August 12, 2009, August 14, 2009, September 3, 2009, September 15, 2009, October 6, 2009, October 23, 2009, November 4, 2009 and January 7, 2010.

        These reports contain important information about us, our financial condition and our results of operations.

        Our quarterly reports listed above do not give effect to the adoption of new guidance issued by the Financial Accounting Standards Board on January 6, 2010 related to the accounting for decreases in ownership of a subsidiary. The new guidance is effective for our financial statements for the fiscal year ended December 31, 2009 and requires retrospective application to all interim periods beginning on or after January 1, 2009. Management is currently evaluating the impact of the adoption of this guidance and will update the financial information in our annual report on Form 10-K for the year ended December 31, 2009. Losses and transaction costs related to our sale of equity interests that were previously recognized in Partner's Capital will be reclassified as a reduction of Net Income (loss) attributable to the Partnership in our Consolidated Statements of Operations.

        You may request a copy of any document incorporated by reference in this prospectus and any exhibit specifically incorporated by reference in those documents, at no cost, by writing or telephoning us at the following address or phone number:

MarkWest Energy Partners, L.P.
1515 Arapahoe Street, Tower 2, Suite 700
Denver, CO 80202-2126
Attention: Nancy K. Buese
(303) 925-9200

        We also make available free of charge on our internet website at http://www.markwest.com our annual reports on Form 10-K, our quarterly reports on Form 10-Q, our current reports on Form 8-K and any amendments to those reports, as soon as reasonably practicable after we electronically file such material with, or furnish it to, the SEC. Information contained on our website is not part of this prospectus and does not constitute a part of this prospectus.

        You should rely only on the information incorporated by reference or provided in this prospectus. We have not authorized anyone else to provide you with any information. You should not assume that the information incorporated by reference or provided in this prospectus is accurate as of any date other than the date on the front of each document. We are subject to the information requirements of the Exchange Act, and in accordance therewith file reports and other information with the SEC. You may read our filings on the SEC's website and at the SEC's Public Reference Room described above. Our common stock trades on the NYSE under the symbol "MWE." Reports that we file with the NYSE may be inspected and copied at the offices of the NYSE described above.

2

FORWARD-LOOKING STATEMENTS

        Statements included or incorporated by reference in this prospectus that are not historical facts are forward-looking statements. We use words such as "could," "may," "predict," "should," "expect," "hope," "continue," "potential," "plan," "intend," "anticipate," "project," "believe," "estimate," and similar expressions to identify forward-looking statements. These forward-looking statements are made based upon management's expectations, estimates, assumptions and beliefs concerning future events impacting us and therefore involve a number of risks and uncertainties. We caution that forward-looking statements are not guarantees and that actual results could differ materially from those expressed or implied in the forward-looking statements. We do not update publicly any forward-looking statement with new information or future events. Investors are cautioned not to put undue reliance on forward-looking statements as many of these factors are beyond our ability to control or predict. Please read "Risk Factors" in Part I, Item 1A. in our most recent annual report on Form 10-K and in Part II, Item 1A in our quarterly reports on Form 10-Q.

3

ABOUT MARKWEST ENERGY PARTNERS

        We are a master limited partnership engaged in the gathering, transportation and processing of natural gas; the transportation, fractionation, marketing and storage of natural gas liquids, or NGLs; and the gathering and transportation of crude oil. We have extensive natural gas gathering, processing and transmission operations in the southwest, Gulf Coast and northeast regions of the United States, including the Marcellus Shale, and are the largest natural gas processor in the Appalachian region.

        Our principal executive offices are located at 1515 Arapahoe Street, Tower 2, Suite 700, Denver, Colorado 80202. We maintain a website at http://www.markwest.com. The information on our website is not part of this prospectus, and you should rely only on information contained in this prospectus or incorporated herein by reference when making an investment decision.

4

RISK FACTORS

An investment in our securities involves a high degree of risk. You should carefully consider the risk factors and all of the other information included in, or incorporated by reference into, this prospectus, including those included in our most recent annual report on Form 10-K and in our quarterly reports on Form 10-Q, in evaluating an investment in our securities. If any of these risks were to occur, our business, financial condition or results of operations could be adversely affected. In that case, the trading price of our common units or debt securities could decline and you could lose all or part of your investment. When we offer and sell any securities pursuant to a prospectus supplement, we may include additional risk factors relevant to such securities in the prospectus supplement.

5

USE OF PROCEEDS

        Unless we specify otherwise in any prospectus supplement, we will use the net proceeds we receive from the sale of securities covered by this prospectus for general corporate purposes, which may include, among other things:

•

paying or refinancing all or a portion of our indebtedness outstanding at the time; and

•

funding working capital, capital expenditures or acquisitions.

        The actual application of proceeds from the sale of any particular offering of securities using this prospectus will be described in the applicable prospectus supplement relating to such offering. The precise amount and timing of the application of these proceeds will depend upon our funding requirements and the availability and cost of other funds.

RATIOS OF EARNINGS TO FIXED CHARGES

        The table below sets forth the ratios of earnings to fixed charges for us for the periods indicated.

	Year Ended December 31,								Nine Months Ended September 30, 2009
	2004		2005	2006		2007	2008
RATIO OF EARNINGS TO FIXED CHARGES		1.33x	(1)		2.27x	(2)		4.07x	(3)

(1)

Earnings were inadequate to cover fixed charges for the year ended December 31, 2005 by $5,859,000.

(2)

Earnings were inadequate to cover fixed charges for the year ended December 31, 2007 by $56,490,000.

(3)

Earnings were inadequate to cover fixed charges for the nine months ended September 30, 2009 by $124,674,000.

        For purposes of computing the ratio of earnings to fixed charges, "earnings" is the aggregate of the following items:

•

pre-tax income or loss from continuing operations before adjustment for non-controlling interest in consolidated subsidiaries or income or loss from equity investees;

•

plus fixed charges;

•

plus distributed income of equity investees;

•

less capitalized interest; and

•

less non-controlling interest in pre-tax income of subsidiaries that have not incurred fixed charges.

        The term "fixed charges" means the sum of the following:

•

interest expense and capitalized interest, including the gain or loss on interest rate swaps and amortization of premiums, discounts and capitalized expenses related to indebtedness; and

•

an estimate of the interest within rental expense.

6

DESCRIPTION OF COMMON UNITS

The Units

        The common units and the Class A units represent limited partner interests in us. The holders of units are entitled to participate in partnership distributions and exercise the rights or privileges available to limited partners under our partnership agreement. For a description of the relative rights and preferences of holders of common units and Class A units in and to partnership distributions, please read "Cash Distribution Policy." For a description of the rights and privileges of limited partners under our partnership agreement, including voting rights, please read "Partnership Agreement."

Transfer Agent and Registrar

Duties

        Wells Fargo Bank, N.A. serves as registrar and transfer agent for the common units. We pay all fees charged by the transfer agent for transfers of common units, except the following that must be paid by unitholders:

•

surety bond premiums to replace lost or stolen certificates, taxes and other governmental charges;

•

special charges for services requested by a holder of a common unit; and

•

other similar fees or charges.

        There is no charge to unitholders for disbursements of our cash distributions. We will indemnify the transfer agent, its agents and each of their stockholders, directors, officers and employees against all claims and losses that may arise out of acts performed or omitted for its activities in that capacity, except for any liability due to any gross negligence or intentional misconduct of the indemnified person or entity.

Resignation or Removal

        The transfer agent may resign, by notice to us, or be removed by us. The resignation or removal of the transfer agent will become effective upon our appointment of a successor transfer agent and registrar and its acceptance of the appointment. If no successor has been appointed and accepted the appointment within 30 days after notice of the resignation or removal, our general partner may act as the transfer agent and registrar until a successor is appointed.

Transfer of Common Units

        The transfer of the common units to persons that purchase directly from the underwriters will be accomplished through the completion, execution and delivery of a transfer application by the investor. Any later transfers of a common unit will not be recorded by the transfer agent or recognized by us unless the transferee executes and delivers a transfer application. By executing and delivering a transfer application, the transferee of common units:

•

becomes the record holder of the common units and is an assignee until admitted into our partnership as a substituted limited partner;

•

automatically requests admission as a substituted limited partner in our partnership;

•

agrees to be bound by the terms and conditions of, and executes, our partnership agreement;

•

represents that the transferee has the capacity, power and authority to enter into the partnership agreement;

7

•

grants powers of attorney to officers of our general partner and any liquidator of us as specified in the partnership agreement; and

•

makes the consents and waivers contained in the partnership agreement.

        An assignee will become a substituted limited partner of our partnership for the transferred common units upon the consent of our general partner and the recording of the name of the assignee on our books and records. Our general partner may withhold its consent in its sole discretion. A transferee's broker, agent or nominee may complete, execute and deliver a transfer application. We are entitled to treat the nominee holder of a common unit as the absolute owner. In that case, the beneficial holder's rights are limited solely to those that it has against the nominee holder as a result of any agreement between the beneficial owner and the nominee holder.

        Common units are securities and are transferable according to the laws governing transfer of securities. In addition to other rights acquired upon transfer, the transferor gives the transferee the right to request admission as a substituted limited partner in our partnership for the transferred common units. A purchaser or transferee of common units who does not execute and deliver a transfer application obtains only:

•

the right to assign the common unit to a purchaser or other transferee; and

•

the right to transfer the right to seek admission as a substituted limited partner in our partnership for the transferred common units.

        Thus, a purchaser or transferee of common units who does not execute and deliver a transfer application:

•

will not receive cash distributions or federal income tax allocations, unless the common units are held in a nominee or "street name" account and the nominee or broker has executed and delivered a transfer application; and

•

may not receive some federal income tax information or reports furnished to record holders of common units.

        The transferor of common units has a duty to provide the transferee with all information that may be necessary to transfer the common units. The transferor does not have a duty to insure the execution of the transfer application by the transferee and has no liability or responsibility if the transferee neglects or chooses not to execute and forward the transfer application to the transfer agent. Please read "Partnership Agreement—Status as Limited Partner or Assignee."

        Until a common unit has been transferred on our books, we and the transfer agent may treat the record holder of the unit as the absolute owner for all purposes, except as otherwise required by law or applicable stock exchange regulations.

8

DESCRIPTION OF OUR DEBT SECURITIES

General

        The debt securities will be:

•

our direct general obligations;

•

either senior debt securities or subordinated debt securities; and

•

issued under separate indentures among us and Wells Fargo Bank, National Association, as Trustee.

        MarkWest Energy Partners, L.P. may issue debt securities in one or more series, and MarkWest Energy Finance Corp. may be a co-issuer of one or more series of debt securities. MarkWest Energy Finance Corp. was incorporated under the laws of the State of Delaware in 2004, is wholly-owned by MarkWest Energy Partners, L.P., and has no material assets or any liabilities other than as a co-issuer of debt securities. Its activities will be limited to co-issuing debt securities and engaging in other activities incidental thereto. When used in this section "Description of the Debt Securities," the terms "we," "us," "our" and "issuers" refer jointly to MarkWest Energy Partners, L.P. and MarkWest Energy Finance Corp., and the terms "MarkWest Energy Partners" and "MarkWest Finance" refer strictly to MarkWest Energy Partners, L.P. and MarkWest Energy Finance Corp., respectively.

        If we offer senior debt securities, we will issue them under a senior indenture. If we issue subordinated debt securities, we will issue them under a subordinated indenture. A form of each indenture is filed as an exhibit to the registration statement of which this prospectus is a part. We have not restated either indenture in its entirety in this description. You should read the relevant indenture because it, and not this description, controls your rights as holders of the debt securities. Capitalized terms used in the summary have the meanings specified in the indentures.

Specific Terms of Each Series of Debt Securities in the Prospectus Supplement

        A prospectus supplement and a supplemental indenture or authorizing resolutions relating to any series of debt securities being offered will include specific terms relating to the offering. These terms will include some or all of the following:

•

whether MarkWest Finance will be a co-issuer;

•

the guarantors of the debt securities, if any;

•

whether the debt securities are senior or subordinated debt securities;

•

the title of the debt securities;

•

the total principal amount of the debt securities;

•

the assets, if any, that are pledged as security for the payment of the debt securities;

•

whether we will issue the debt securities in individual certificates to each holder in registered form, or in the form of temporary or permanent global securities held by a depository on behalf of holders;

•

the prices at which we will issue the debt securities;

•

the portion of the principal amount that will be payable if the maturity of the debt securities is accelerated;

•

the currency or currency unit in which the debt securities will be payable, if not U.S. dollars;

•

the dates on which the principal of the debt securities will be payable;

9

•

the interest rate that the debt securities will bear and the interest payment dates for the debt securities;

•

any conversion or exchange provisions;

•

any optional redemption provisions;

•

any sinking fund or other provisions that would obligate us to repurchase or otherwise redeem the debt securities;

•

any changes to or additional events of default or covenants; and

•

any other terms of the debt securities.

        We may offer and sell debt securities, including original issue discount debt securities, at a substantial discount below their principal amount. The prospectus supplement will describe special U.S. federal income tax and any other considerations applicable to those securities. In addition, the prospectus supplement may describe certain special U.S. federal income tax or other considerations applicable to any debt securities that are denominated in a currency other than U.S. dollars.

Guarantees

        If specified in the prospectus supplement respecting a series of debt securities, the subsidiaries of MarkWest Energy Partners specified in the prospectus supplement will unconditionally guarantee to each holder and the Trustee, on a joint and several basis, the full and prompt payment of principal of, premium, if any, and interest on the debt securities of that series when and as the same become due and payable, whether at stated maturity, upon redemption or repurchase, by declaration of acceleration or otherwise. If a series of debt securities is guaranteed, such series will be guaranteed by all wholly-owned subsidiaries other than "minor" subsidiaries as such term is interpreted in securities regulation governing financial reporting for guarantors. The prospectus supplement will describe any limitation on the maximum amount of any particular guarantee and the conditions under which guarantees may be released.

        The guarantees will be general obligations of the guarantors. Guarantees of subordinated debt securities will be subordinated to the Senior Indebtedness of the guarantors on the same basis as the subordinated debt securities are subordinated to the Senior Indebtedness of MarkWest Energy Partners.

Consolidation, Merger or Asset Sale

        Each indenture will, in general, allow us to consolidate or merge with or into another domestic entity. It will also allow each issuer to sell, lease, transfer or otherwise dispose of all or substantially all of its assets to another domestic entity. If this happens, the remaining or acquiring entity must assume all of the issuer's responsibilities and liabilities under the indenture including the payment of all amounts due on the debt securities and performance of the issuer's covenants in the indenture.

        However, each indenture will impose certain requirements with respect to any consolidation or merger with or into an entity, or any sale, lease, transfer or other disposition of all or substantially all of an issuer's assets, including:

•

the remaining or acquiring entity must be organized under the laws of the United States, any state or the District of Columbia;

•

the remaining or acquiring entity must assume the issuer's obligations under the indenture; and

•

immediately after giving effect to the transaction, no Default or Event of Default (as defined under "—Events of Default and Remedies" below) may exist.

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        The remaining or acquiring entity will be substituted for the issuer in the indenture with the same effect as if it had been an original party to the indenture, and the issuer will be relieved from any further obligations under the indenture.

No Protection in the Event of a Change of Control

        Unless otherwise set forth in the prospectus supplement, the debt securities will not contain any provisions that protect the holders of the debt securities in the event of a change of control of us or in the event of a highly leveraged transaction, whether or not such transaction results in a change of control of us.

Modification of Indentures

        We may supplement or amend an indenture if the holders of a majority in aggregate principal amount of the outstanding debt securities of all series issued under the indenture affected by the supplement or amendment consent to it. Further, the holders of a majority in aggregate principal amount of the outstanding debt securities of any series may waive past defaults under the indenture and compliance by us with our covenants with respect to the debt securities of that series only. Those holders may not, however, waive any default in any payment on any debt security of that series or compliance with a provision that cannot be supplemented or amended without the consent of each holder affected. Without the consent of each outstanding debt security affected, no modification of the indenture or waiver may:

•

reduce the principal amount of debt securities whose holders must consent to an amendment, supplement or waiver;

•

reduce the principal of or change the fixed maturity of any debt security;

•

reduce or waive the premium payable upon redemption or alter or waive the provisions with respect to the redemption of the debt securities (except as may be permitted in the case of a particular series of debt securities);

•

reduce the rate of or change the time for payment of interest on any debt security;

•

waive a Default or an Event of Default in the payment of principal of or premium, if any, or interest on the debt securities (except a rescission of acceleration of the debt securities by the holders of at least a majority in aggregate principal amount of the debt securities and a waiver of the payment default that resulted from such acceleration);

•

except as otherwise permitted under the indenture, release any security that may have been granted with respect to the debt securities;

•

make any debt security payable in currency other than that stated in the debt securities;

•

in the case of any subordinated debt security, make any change in the subordination provisions that adversely affects the rights of any holder under those provisions;

•

make any change in the provisions of the indenture relating to waivers of past Defaults or the rights of holders of debt securities to receive payments of principal of or premium, if any, or interest on the debt securities;

•

waive a redemption payment with respect to any debt security (except as may be permitted in the case of a particular series of debt securities);

•

except as otherwise permitted in the indenture, release any guarantor from its obligations under its guarantee or the indenture or change any guarantee in any manner that would adversely affect the rights of holders; or

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•

make any change in the preceding amendment, supplement and waiver provisions (except to increase any percentage set forth therein).

        We may supplement or amend an indenture without the consent of any holders of the debt securities in certain circumstances, including:

•

to establish the form of terms of any series of debt securities;

•

to cure any ambiguity, defect or inconsistency;

•

to provide for the assumption of an issuer's or guarantor's obligations to holders of debt securities in the case of a merger or consolidation or disposition of all or substantially all of such issuer's or guarantor's assets;

•

in the case of any subordinated debt security, to make any change in the subordination provisions that limits or terminates the benefits applicable to any holder of Senior Indebtedness of MarkWest Energy Partners;

•

to add or release guarantors pursuant to the terms of the indenture;

•

to make any changes that would provide any additional rights or benefits to the holders of debt securities or that do not, taken as a whole, adversely affect the rights under the indenture of any holder of debt securities;

•

to evidence or provide for the acceptance of appointment under the indenture of a successor Trustee;

•

to add any additional Events of Default; or

•

to secure the debt securities and/or the guarantees.

Events of Default and Remedies

        "Event of Default," when used in an indenture, will mean any of the following with respect to the debt securities of any series:

•

failure to pay when due the principal of or any premium on any debt security of that series;

•

failure to pay, within 60 days of the due date, interest on any debt security of that series;

•

failure to pay when due any sinking fund payment with respect to any debt securities of that series;

•

failure on the part of the issuers to comply with the covenant described under "—Consolidation, Merger or Asset Sale";

•

failure to perform any other covenant in the indenture that continues for 30 days after written notice is given to the issuers;

•

certain events of bankruptcy, insolvency or reorganization of an issuer; or

•

any other Event of Default provided under the terms of the debt securities of that series.

        An Event of Default for a particular series of debt securities will not necessarily constitute an Event of Default for any other series of debt securities issued under an indenture. The Trustee may withhold notice to the holders of debt securities of any default (except in the payment of principal, premium, if any, or interest) if it considers such withholding of notice to be in the best interests of the holders.

        If an Event of Default for any series of debt securities occurs and continues, the Trustee or the holders of at least 25% in aggregate principal amount of the debt securities of the series may declare

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the entire principal of, and accrued interest on, all the debt securities of that series to be due and payable immediately. If this happens, subject to certain conditions, the holders of a majority in the aggregate principal amount of the debt securities of that series can rescind the declaration.

        Other than its duties in case of a default, a Trustee is not obligated to exercise any of its rights or powers under either indenture at the request, order or direction of any holders, unless the holders offer the Trustee reasonable security or indemnity. If they provide this reasonable security or indemnification, the holders of a majority in aggregate principal amount of any series of debt securities may direct the time, method and place of conducting any proceeding or any remedy available to the Trustee, or exercising any power conferred upon the Trustee, for that series of debt securities.

No Limit on Amount of Debt Securities

        Neither indenture will limit the amount of debt securities that we may issue, unless we indicate otherwise in a prospectus supplement. Each indenture will allow us to issue debt securities of any series up to the aggregate principal amount that we authorize.

Registration of Notes

        We will issue debt securities of a series only in registered form, without coupons, unless otherwise indicated in the prospectus supplement.

Minimum Denominations

        Unless the prospectus supplement states otherwise, the debt securities will be issued only in principal amounts of $1,000 each or integral multiples of $1,000.

No Personal Liability

        None of the past, present or future partners, incorporators, managers, members, directors, officers, employees, unitholders or stockholders of either issuer, the general partner of MarkWest Energy Partners or any guarantor will have any liability for the obligations of the issuers or any guarantors under either indenture or the debt securities or for any claim based on such obligations or their creation. Each holder of debt securities by accepting a debt security waives and releases all such liability. The waiver and release are part of the consideration for the issuance of the debt securities. The waiver may not be effective under federal securities laws, however.

Payment and Transfer

        The Trustee will initially act as paying agent and registrar under each indenture. The issuers may change the paying agent or registrar without prior notice to the holders of debt securities, and the issuers or any of their subsidiaries may act as paying agent or registrar.

        If a holder of debt securities has given wire transfer instructions to the issuers, the issuers will make all payments on the debt securities in accordance with those instructions. All other payments on the debt securities will be made at the corporate trust office of the Trustee, unless the issuers elect to make interest payments by check mailed to the holders at their addresses set forth in the debt security register.

        The Trustee and any paying agent will repay to us upon request any funds held by them for payments on the debt securities that remain unclaimed for two years after the date upon which that payment has become due. After payment to us, holders entitled to the money must look to us for payment as general creditors.

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Exchange, Registration and Transfer

        Debt securities of any series will be exchangeable for other debt securities of the same series, the same total principal amount and the same terms but in different authorized denominations in accordance with the indenture. Holders may present debt securities for exchange or registration of transfer at the office of the registrar. The registrar will effect the transfer or exchange when it is satisfied with the documents of title and identity of the person making the request. We will not charge a service charge for any registration of transfer or exchange of the debt securities. We may, however, require the payment of any tax or other governmental charge payable for that registration.

        We will not be required:

•

to issue, register the transfer of, or exchange debt securities of a series either during a period beginning 15 business days prior to the selection of debt securities of that series for redemption and ending on the close of business on the day of mailing of the relevant notice of redemption or repurchase, or between a record date and the next succeeding interest payment date; or

•

to register the transfer of or exchange any debt security called for redemption or repurchase, except the unredeemed portion of any debt security we are redeeming or repurchasing in part.

Provisions Relating only to the Senior Debt Securities

        The senior debt securities will rank equally in right of payment with all of our other senior and unsubordinated debt. The senior debt securities will be effectively subordinated, however, to all of our secured debt to the extent of the value of the collateral for that debt. We will disclose the amount of our secured debt in the prospectus supplement.

Provisions Relating only to the Subordinated Debt Securities

Subordinated Debt Securities Subordinated to Senior Indebtedness

        The subordinated debt securities will rank junior in right of payment to all of the Senior Indebtedness of MarkWest Energy Partners. "Senior Indebtedness" will be defined in a supplemental indenture or authorizing resolutions respecting any issuance of a series of subordinated debt securities, and the definition will be set forth in the prospectus supplement.

Payment Blockages

        The subordinated indenture will provide that no payment of principal, interest and any premium on the subordinated debt securities may be made in the event:

•

we or our property is involved in any voluntary or involuntary liquidation or bankruptcy;

•

we fail to pay the principal, interest, any premium or any other amounts on any Senior Indebtedness of MarkWest Energy Partners within any applicable grace period or the maturity of such Senior Indebtedness is accelerated following any other default, subject to certain limited exceptions set forth in the subordinated indenture; or

•

any other default on any Senior Indebtedness of MarkWest Energy Partners occurs that permits immediate acceleration of its maturity, in which case a payment blockage on the subordinated debt securities will be imposed for a maximum of 179 days at any one time.

No Limitation on Amount of Senior Debt

        The subordinated indenture will not limit the amount of Senior Indebtedness that MarkWest Energy Partners may incur, unless otherwise indicated in the prospectus supplement.

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Book Entry, Delivery and Form

        The debt securities of a particular series may be issued in whole or in part in the form of one or more global certificates that will be deposited with the Trustee as custodian for The Depository Trust Company, New York, New York ("DTC"), and registered in the name of DTC's nominee, Cede & Co. This means that we will not issue certificates to each holder. Instead, one or more global debt securities will be issued to DTC, who will keep a computerized record of its participants (for example, your broker) whose clients have purchased the debt securities. The participant will then keep a record of its clients who purchased the debt securities. Unless it is exchanged in whole or in part for a certificated debt security, a global debt security may not be transferred, except that DTC, its nominees and their successors may transfer a global debt security as a whole to one another.

        Beneficial interests in global debt securities will be shown on, and transfers of beneficial interests in global debt securities will be made only through, records maintained by DTC and its participants.

        DTC has provided us the following information: DTC is a limited-purpose trust company organized under the New York Banking Law, a "banking organization" within the meaning of the New York Banking Law, a member of the United States Federal Reserve System, a "clearing corporation" within the meaning of the New York Uniform Commercial Code and a "clearing agency" registered under the provisions of Section 17A of the Securities Exchange Act of 1934. DTC holds securities that its participants ("Direct Participants") deposit with DTC. DTC also records the settlement among Direct Participants of securities transactions, such as transfers and pledges, in deposited securities through computerized records for Direct Participants' accounts. This eliminates the need to exchange certificates. Direct Participants include securities brokers and dealers, banks, trust companies, clearing corporations and certain other organizations.

        DTC's book-entry system is also used by other organizations such as securities brokers and dealers, banks and trust companies that work through a Direct Participant. The rules that apply to DTC and its Direct Participants are on file with the SEC.

        We will wire all payments on the global debt securities to DTC's nominee. We and the Trustee will treat DTC's nominee as the owner of the global debt securities for all purposes. Accordingly, we, the Trustee and any paying agent will have no direct responsibility or liability to pay amounts due on the global debt securities to owners of beneficial interests in the global debt securities.

        It is DTC's current practice, upon receipt of any payment on the global debt securities, to credit Direct Participants' accounts on the payment date according to their respective holdings of beneficial interests in the global debt securities as shown on DTC's records. In addition, it is DTC's current practice to assign any consenting or voting rights to Direct Participants whose accounts are credited with debt securities on a record date, by using an omnibus proxy. Payments by Direct Participants to owners of beneficial interests in the global debt securities, and voting by Direct Participants, will be governed by the customary practices between the Direct Participants and owners of beneficial interests, as is the case with debt securities held for the account of customers registered in "street name." However, payments will be the responsibility of the Direct Participants and not of DTC, the Trustee or us.

        Debt securities represented by a global debt security will be exchangeable for certificated debt securities with the same terms in authorized denominations only if:

•

DTC notifies us that it is unwilling or unable to continue as depositary or if DTC ceases to be a clearing agency registered under applicable law and in either event a successor depositary is not appointed by us within 90 days; or

•

we determine not to require all of the debt securities of a series to be represented by a global debt security.

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Satisfaction and Discharge; Defeasance

        Each indenture will be discharged and will cease to be of further effect as to all outstanding debt securities of any series issued thereunder, when:

(a)

either:



(1)

all outstanding debt securities of that series that have been authenticated (except lost, stolen or destroyed debt securities that have been replaced or paid and debt securities for whose payment money has theretofore been deposited in trust and thereafter repaid to us) have been delivered to the Trustee for cancellation; or



(2)

all outstanding debt securities of that series that have not been delivered to the Trustee for cancellation have become due and payable by reason of the giving of a notice of redemption or otherwise or will become due and payable at their stated maturity within one year or are to be called for redemption within one year under arrangements satisfactory to the Trustee and in any case we have irrevocably deposited or caused to be irrevocably deposited with the Trustee as trust funds in trust cash in U.S. dollars, non-callable U.S. Government Obligations or a combination thereof, in such amounts as will be sufficient, without consideration of any reinvestment of interest, to pay and discharge the entire indebtedness of such debt securities not delivered to the Trustee for cancellation, for principal, premium, if any, and accrued interest to the date of such deposit (in the case of debt securities that have been due and payable) or the stated maturity or redemption date;



(b)

we have paid or caused to be paid all other sums payable by us under the indenture; and



(c)

we have delivered an officers' certificate and an opinion of counsel to the Trustee stating that all conditions precedent to satisfaction and discharge have been satisfied.

        The debt securities of a particular series will be subject to legal or covenant defeasance to the extent, and upon the terms and conditions, set forth in the prospectus supplement.

The Trustee

        Wells Fargo Bank, National Association will be the initial Trustee under each indenture. We maintain a banking relation in the ordinary course of business with Wells Fargo, National Association and some of its affiliates.

Limitations on Trustee if it is a Creditor

        Each indenture will limit the right of the Trustee thereunder, in the event that it becomes a creditor of an issuer or guarantor, to obtain payment of claims in certain cases, or to realize on certain property received in respect of any such claim as security or otherwise.

Certificates and Opinions to be Furnished to Trustee

        Each indenture will provide that, in addition to other certificates or opinions that may be specifically required by other provisions of the indenture, every application by us for action by the Trustee must be accompanied by a certificate of certain of our officers and an opinion of counsel (who may be our counsel) stating that, in the opinion of the signers, all conditions precedent to such action have been complied with by us.

Governing Law

        Each indenture and all of the debt securities will be governed by the laws of the State of New York.

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CASH DISTRIBUTION POLICY

Distributions of Available Cash

        General.    Within 45 days after the end of each quarter, we distribute all of our available cash to our unitholders of record on the applicable record date. We will make distributions of available cash to all our unitholders (common and Class A), pro rata and we will make distributions of Hydrocarbon Available Cash (as defined below) pro rata to our common unitholders.

        Definition of Available Cash.    We define available cash in our amended and restated partnership agreement, and it generally means, for each fiscal quarter:

•

all cash and cash equivalents on hand at the end of the quarter (excluding cash at MarkWest Hydrocarbon);

•

less the amount of cash that our general partner determines in its reasonable discretion is necessary or appropriate to:

•

provide for the proper conduct of our business;

•

comply with applicable law, any of our debt instruments, or other agreements; or

•

provide funds for distributions to our unitholders for any one or more of the next four quarters;

•

plus all cash and cash equivalents on hand on the date of determination of available cash for the quarter resulting from working capital borrowings made after the end of the quarter. Working capital borrowings are generally borrowings that are made under our revolving credit facility and in all cases are used solely for working capital purposes or to pay distributions to partners.

        Hydrocarbon Available Cash.    Generally, Hydrocarbon Available Cash is defined as all cash and cash equivalents on hand derived from or attributable to our ownership of, or sale or other disposition of, the shares of common stock of MarkWest Hydrocarbon.

        Contractual Restrictions on Our Ability to Distribute Available Cash.    Our ability to distribute available cash is contractually restricted by the terms of our credit agreement. Our credit agreement contains covenants requiring us to maintain certain financial ratios and a minimum net worth. We are prohibited from making any distribution to unitholders if such distribution would cause an event of default or otherwise violate a covenant under our credit agreement. In addition, our credit agreement prohibits us from borrowing more than $0.75 per outstanding unit during any consecutive 12-month period for the purpose of making distributions to our unitholders. Our credit agreement provides that any amount so borrowed must be repaid once annually.

Distributions of Cash Upon Liquidation

        If we dissolve in accordance with our partnership agreement, we will sell or otherwise dispose of our assets in a process called liquidation. We will first apply the proceeds of liquidation to the payment of our creditors. We will distribute any remaining proceeds to our unitholders, in accordance with their capital account balances, as adjusted to reflect any gain or loss upon the sale or other disposition of our assets in liquidation.

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PARTNERSHIP AGREEMENT

        The following is a summary of the material provisions of the third amended and restated partnership agreement, which our general partner, MarkWest Energy GP, L.L.C. (the "General Partner"), adopted in connection with the merger with MarkWest Hydrocarbon, Inc. and is referred to herein as the "amended and restated partnership agreement."

        We summarize the following provisions of the amended and restated partnership agreement elsewhere in this prospectus:

•

with regard to cash available for distribution, please read "Cash Distribution Policy."

•

with regard to the transfer of Partnership common units, please read "Description of the Common Units—Transfer of Common Units."

•

with regard to allocations of taxable income and taxable loss, please read "Material Tax Consequences."

Organization and Duration

        We were organized on January 25, 2002 and will have a perpetual existence, unless dissolved in accordance with Article XII of the amended and restated partnership agreement.

Purpose

        Our purpose under the amended and restated partnership agreement is limited to serving as a member of our operating company, MarkWest Energy Operating Company, L.L.C., which we refer to as "Opco," and engaging in any business activities that may be engaged in by Opco or that are approved by the General Partner. All of our operations are conducted through Opco and its subsidiaries or MarkWest Hydrocarbon. We own 100% of the outstanding membership interest of Opco and 100% of the outstanding common stock of MarkWest Hydrocarbon. The limited liability company agreement of Opco provides that Opco may, directly or indirectly, engage in:

•

its operations as conducted immediately before our initial public offering;

•

any other activity approved by the General Partner but only to the extent that the General Partner reasonably determines that, as of the date of the acquisition or commencement of the activity, the activity generates "qualifying income" as this term is defined in Section 7704 of the Internal Revenue Code; or

•

any activity that enhances the operations of an activity that is described in either of the two preceding clauses or any other activity provided such activity does not affect our treatment as a partnership for federal income tax purposes.

        The General Partner is authorized in general to perform all acts deemed necessary to carry out our purposes and to conduct our business.

Power of Attorney

        Each limited partner, and each person who acquires one of our common units from one of our unitholders and executes and delivers a transfer application, grants to the General Partner and, if appointed, a liquidator, a power of attorney to, among other things, execute and file documents required for our qualification, continuance or dissolution. The power of attorney also grants the General Partner the authority to amend, and to make consents and waivers under, the amended and restated partnership agreement subject to the terms thereof.

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Capital Contributions

        Our unitholders are not obligated to make additional capital contributions, except as described below under "—Limited Liability."

Partnership Class A Units

        Class A units represent limited partner interests in us and have identical rights and obligations of our common units except that Class A units (a) do not have the right to vote on, approve or disapprove, or otherwise consent to or not consent to any matter (including mergers, share exchanges and similar statutory authorizations) except as otherwise required by any non-waivable provision of law and (b) do not share in any cash and cash equivalents on hand, income, gains, losses, deductions and credits that are derived from or attributable to our ownership of, or sale or disposition of, the shares of MarkWest Hydrocarbon common stock.

Limited Liability

        Assuming that a limited partner does not participate in the control of our business within the meaning of the Delaware Act and that he otherwise acts in conformity with the provisions of the amended and restated partnership agreement, his liability under the Delaware Act will be limited, subject to possible exceptions, to the amount of capital he is obligated to contribute to us for his common units in us plus his share of any undistributed profits and assets. If it were determined, however, that the right, or exercise of the right, by the limited partners as a group:

•

to approve some amendments to the amended and restated partnership agreement; or

•

to take other action under the amended and restated partnership agreement

constituted "participation in the control" of our business for the purposes of the Delaware Act, then the limited partners could be held personally liable for our obligations under the laws of Delaware, to the same extent as the General Partner. This liability would extend to persons who transact business with us who reasonably believe that a limited partner is a general partner based on the limited partner's conduct. Neither the amended and restated partnership agreement nor the Delaware Act specifically provides for legal recourse against the General Partner if a limited partner were to lose limited liability through any fault of the General Partner. While this does not mean that a limited partner could not seek legal recourse, we know of no precedent for this type of a claim in Delaware case law.

        Under the Delaware Act, a limited partnership may not make a distribution to a partner if, after the distribution, all liabilities of the limited partnership, other than liabilities to partners on account of their partnership interests and liabilities for which the recourse of creditors is limited to specific property of us, would exceed the fair value of the assets of the limited partnership. For the purpose of determining the fair value of the assets of a limited partnership, the Delaware Act provides that the fair value of property subject to liability for which recourse of creditors is limited will be included in the assets of the limited partnership only to the extent that the fair value of that property exceeds the nonrecourse liability. The Delaware Act provides that a limited partner who receives a distribution and knew at the time of the distribution that the distribution was in violation of the Delaware Act will be liable to the limited partnership for the amount of the distribution for three years from the date of distribution. Under the Delaware Act, an assignee who becomes a substituted limited partner of a limited partnership is liable for the obligations of his assignor to make contributions to us, except the assignee is not obligated for liabilities unknown to him at the time he became a limited partner and that could not be ascertained from the amended and restated partnership agreement.

        Our subsidiaries conduct business in multiple states. Maintenance of our limited liability as a member of Opco may require compliance with legal requirements in the jurisdictions in which Opco conducts business, including qualifying our subsidiaries to do business there. Limitations on the liability

19

of members for the obligations of a limited liability company have not been clearly established in many jurisdictions. If, by virtue of our membership interest in Opco or otherwise, it were determined that we were conducting business in any state without compliance with the applicable limited partnership or limited liability company statute, or that the right or exercise of the right by the limited partners as a group to remove or replace the General Partner, to approve some amendments to the amended and restated partnership agreement, or to take other action under the amended and restated partnership agreement constituted "participation in the control" of our business for purposes of the statutes of any relevant jurisdiction, then the limited partners could be held personally liable for our obligations under the law of that jurisdiction to the same extent as the General Partner under the circumstances. We will operate in a manner that the General Partner considers reasonable and necessary or appropriate to preserve the limited liability of the limited partners.

Voting Rights

        The following matters specified below require a vote of our unitholders.

Election of directors of the General Partner	Plurality of the votes cast at meetings of the limited partners.
Amendment of the amended and restated partnership agreement	Certain amendments may be made by the General Partner without the approval of our unitholders. Other amendments generally require the approval of a majority of our outstanding common units. Please read "—Amendment of the Amended and Restated Partnership Agreement."
Merger or the sale of all or substantially all of our assets	Majority of our outstanding common units. Please read "—Merger, Sale or Other Disposition of Assets."
Dissolution of us	Majority of our outstanding common units. Please read "—Termination and Dissolution."
Amendment of the limited liability company agreement and other action taken by us as sole member of Opco	Majority of our outstanding common units if such amendment or other action would adversely affect our limited partners (or any particular class of limited partners) in any material respect. Please read "—Action Relating to the Operating Company."

Issuance of Additional Securities

        The amended and restated partnership agreement authorizes us to issue an unlimited number of additional partnership securities and rights to buy partnership securities for the consideration and on the terms and conditions established by the General Partner in its sole discretion without the approval of our unitholders.

        It is possible that we will fund acquisitions through the issuance of additional common units in us or other equity securities. Holders of any additional common units in us that we issue will be entitled to share equally with the then-existing holders of our common units in distributions of available cash. In addition, the issuance of additional partnership interests may dilute the value of the interests of the then-existing holders of our common units in our net assets.

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        In accordance with Delaware law and the provisions of the amended and restated partnership agreement, we may also issue additional partnership interests that, in the sole discretion of the General Partner, have special voting rights to which holders of our common units are not entitled.

Amendment of the Amended and Restated Partnership Agreement

        General.    Amendments to the amended and restated partnership agreement may be proposed only by or with the consent of the General Partner, which consent may be given or withheld in its sole discretion, except as discussed below. In order to adopt a proposed amendment, other than the amendments discussed below, the General Partner must seek written approval of the holders of the number of our common units required to approve the amendment or call a meeting of the limited partners to consider and vote upon the proposed amendment. Except as described below, an amendment must be approved by a majority of our outstanding common units.

        Prohibited Amendments.    No amendment may be made that would:

•

enlarge the obligations of any limited partner without its consent, unless approved by at least a majority of the type or class of limited partner interests so affected;

•

enlarge the obligations of, restrict in any way any action by or rights of, or reduce in any way the amounts distributable, reimbursable or otherwise payable by us to the General Partner or any of its affiliates without the consent of the General Partner, which may be given or withheld in its sole discretion;

•

change the term of the Partnership;

•

provide that we are not dissolved upon an election to dissolve us by the General Partner that is approved by a majority of outstanding common units; or

•

give any person the right to dissolve us other than the General Partner's right to dissolve us with the approval of a majority of our outstanding common units.

        The provision of the amended and restated partnership agreement preventing the amendments having the effects described in any of the clauses above can be amended upon the approval of the holders of at least 90% of our outstanding common units voting together as a single class.

        No Partnership Unitholder Approval.    The General Partner may generally make amendments to the amended and restated partnership agreement without the approval of any limited partner or assignee to reflect:

•

a change in our name, the location of our principal place of business, our registered agent or our registered office;

•

the admission, substitution, withdrawal, or removal of partners, as applicable, in accordance with the amended and restated partnership agreement;

•

a change that, in the sole discretion of the General Partner, is necessary or advisable for us to qualify or to continue our qualification as a limited partnership or a partnership in which the limited partners have limited liability under the laws of any state or to ensure that none of us, Opco and its subsidiaries will be treated as an association taxable as a corporation or otherwise taxed as an entity for federal income tax purposes;

•

an amendment that is necessary, in the opinion of our counsel, to prevent us or the General Partner or its directors, officers, agents, or trustees from in any manner being subjected to the provisions of the Investment Company Act of 1940, the Investment Advisers Act of 1940, or plan asset regulations adopted under the Employee Retirement Income Security Act of 1974, whether or not substantially similar to plan asset regulations currently applied or proposed;

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•

subject to the limitations on the issuance of additional partnership securities described above, an amendment that in the discretion of the General Partner is necessary or advisable for the authorization of additional partnership securities or rights to acquire partnership securities;

•

any amendment expressly permitted in the amended and restated partnership agreement to be made by the General Partner acting alone;

•

an amendment effected, necessitated or contemplated by a redemption and merger agreement that has been approved in accordance with the terms of the amended and restated partnership agreement;

•

any amendment that, in the discretion of the General Partner, is necessary or advisable for the formation by us of, or our investment in, any corporation, partnership or other entity, as otherwise permitted by the amended and restated partnership agreement;

•

a merger or conveyance the sole purpose of which is to effect a change in the legal form of us to another limited liability entity;

•

a change in our fiscal year or taxable year and related changes; or

•

any other amendments substantially similar to any of the matters described in the clauses above.

        In addition, the General Partner may make amendments to the amended and restated partnership agreement without the approval of any limited partner or assignee if those amendments, in the discretion of the general partner:

•

do not adversely affect the limited partners (or any particular class of limited partners) in any material respect;

•

are necessary or advisable to satisfy any requirements, conditions or guidelines contained in any opinion, directive, order, ruling or regulation of any federal or state agency or judicial authority or contained in any federal or state statute;

•

are necessary or advisable to facilitate the trading of limited partner interests or to comply with any rule, regulation, guideline or requirement of any securities exchange on which the limited partner interests are or will be listed for trading, compliance with any of which the General Partner deems to be in our best interest and the best interest of the limited partners;

•

are necessary or advisable for any action taken by the General Partner relating to splits or combinations of units under the provisions of the amended and restated partnership agreement; or

•

are required to effect the intent of the provisions of the amended and restated partnership agreement or are otherwise contemplated by the amended and restated partnership agreement.

        Opinion of Counsel and Partnership Unitholder Approval.    The General Partner will not be required to obtain an opinion of counsel that an amendment will not result in a loss of limited liability to the limited partners or result in us being treated as an entity for federal income tax purposes if one of the amendments described above under "—No Partnership Unitholder Approval" should occur. No other amendments to the amended and restated partnership agreement will become effective without the approval of holders of at least 90% of the outstanding Partnership common units unless we obtain an opinion of counsel to the effect that the amendment will not affect the limited liability under applicable law of any of our limited partners or cause us, Opco or its subsidiaries to be taxable as a corporation or otherwise to be taxed as an entity for federal income tax purposes (to the extent not previously taxed as such).

        Any amendment that would have a material adverse effect on the rights or preferences of any type or class of outstanding units in relation to other classes of units will require the approval of at least a

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majority of the type or class of units so affected. Any amendment that reduces the voting percentage required to take any action must be approved by the affirmative vote of limited partners constituting not less than the voting requirement sought to be reduced.

        Amendments requiring 80% of the Outstanding Partnership Common Units.    Any amendments regarding provisions dealing with amendments to the amended and restated partnership agreement, limited partner meetings and related to election of the directors of the General Partner board at annual meetings, quorum, action without a meeting and voting rights cannot be amended without 80% of our outstanding common units voting in favor of such amendments.

Action Relating to the Operating Company

        Without the approval of the holders of a majority of our outstanding common units, the General Partner is prohibited from consenting on our behalf, as the sole member of Opco, to any amendment to the limited liability company agreement of Opco or taking any action on our behalf permitted to be taken by a member of Opco in each case that would adversely affect our limited partners (or any particular class of limited partners) in any material respect.

Merger, Sale or Other Disposition of Assets

        The amended and restated partnership agreement generally prohibits the General Partner, without the prior approval of the holders of a majority of our outstanding common units, from causing us to, among other things, sell, exchange or otherwise dispose of all or substantially all of our assets in a single transaction or a series of related transactions, including by way of merger, consolidation or other combination, or approving on our behalf the sale, exchange or other disposition of all or substantially all of the assets of our subsidiaries as a whole. The General Partner may, however, mortgage, pledge, hypothecate or grant a security interest in all or substantially all of our assets without that approval. The General Partner may also sell all or substantially all of our assets under a foreclosure or other realization upon those encumbrances without such approval.

        If conditions specified in the amended and restated partnership agreement are satisfied, the General Partner may merge us or any of our subsidiaries into, or convey some or all of our assets to, a newly formed entity if the sole purpose of that merger or conveyance is to change our legal form into another limited liability entity. Our unitholders are not entitled to appraisal rights under the amended and restated partnership agreement or applicable Delaware law in the event of a merger or consolidation, a sale of substantially all of our assets or any other transaction or event for such purpose.

Termination and Dissolution

        We will continue as a limited partnership until terminated under the amended and restated partnership agreement. We will dissolve upon:

•

the election of the General Partner to dissolve us, if approved by the holders of a majority of our outstanding common units;

•

the sale, exchange or other disposition of all or substantially all of our assets and properties and our subsidiaries;

•

the entry of a decree of judicial dissolution of us; or

•

the withdrawal of the General Partner in violation of the amended and restated partnership agreement and the successor general partner is not admitted.

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Liquidation and Distribution of Proceeds

        Upon our dissolution, the liquidator authorized to wind up our affairs will, acting with all of the powers of the General Partner that the liquidator deems necessary or desirable in its judgment, liquidate our assets and apply the proceeds of the liquidation as provided in "Cash Distribution Policy—Distributions of Cash Upon Liquidation." The liquidator may defer liquidation of our assets for a reasonable period or distribute assets to partners in kind if it determines that a sale would be impractical or would cause undue loss to the partners.

No Withdrawal or Removal of the General Partner

        The General Partner cannot withdraw and cannot be removed at any time for any reason. Any attempt of withdrawal or removal of the General Partner will be null and void. Nonetheless, if the General Partner withdraws in violation of the amended and restated partnership agreement:

•

the withdrawing General Partner must give 90 days notice to the limited partners;

•

the successor general partner will be elected by a plurality of the votes of our unitholders at a special meeting or an annual meeting;

•

the successor general partner elected will be admitted to the Partnership as the general partner effective immediately prior to the withdrawal of the predecessor general partner;

•

the successor general partner elected will automatically become the successor general partner or managing member of our subsidiaries; and

•

if the successor general partner is elected, we will not be dissolved and the successor general partner will continue the business of us.

Transfer of General Partner Interests

        The General Partner interests cannot be transferred to any person for any reason. So long as we are a limited partnership, 100% of the General Partner interests will be owned by the Partnership or one or more of its wholly owned subsidiaries.

Change of Management Provisions

        The amended and restated partnership agreement contains specific provisions that are intended to discourage a person or group from attempting to remove MarkWest Energy GP, L.L.C. as the general partner or otherwise change management. If any person or group other than the General Partner and its affiliates acquires beneficial ownership of 20% or more of any class of units, that person or group loses voting rights on all of its units. This loss of voting rights does not apply to any person or group who acquires the units with the prior approval of the General Partner board.

Meetings; Voting

        Except as described below regarding a person or group owning 20% or more of any class of units then outstanding, unitholders or assignees who are record holders of our common units on the record date will be entitled to notice of, and to vote at, meetings of our limited partners and to act upon matters for which approvals may be solicited. Our common units that are owned by an assignee who is a record holder, but who has not yet been admitted as a limited partner, will be voted by the General Partner at the written direction of the record holder. Absent direction of this kind, our common units will not be voted.

        Any action that is required or permitted to be taken by unitholders may be taken either at a meeting of our unitholders or without a meeting if consents in writing describing the action so taken

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are signed by holders of the number of units necessary to authorize or take that action at a meeting. Meetings of our unitholders may be called by the General Partner or by our unitholders owning at least 20% of our outstanding common units. Our unitholders may vote either in person or by proxy at meetings. The holders of a majority of the outstanding common units, represented in person or by proxy, will constitute a quorum unless any action by our unitholders requires approval by holders of a greater percentage of our common units, in which case the quorum will be the greater percentage.

        However, if at any time any person or group, other than the General Partner and its affiliates, or a direct or subsequently approved transferee of the General Partner or its affiliates, acquires, in the aggregate, beneficial ownership of 20% or more of any class of units then outstanding, that person or group will lose voting rights on all of its units and the units may not be voted on any matter and will not be considered to be outstanding when sending notices of a meeting of unitholders, calculating required votes, determining the presence of a quorum or for other similar purposes. Our common units held in nominee or street name account will be voted by the broker or other nominee in accordance with the instruction of the beneficial owner unless the arrangement between the beneficial owner and his nominee provides otherwise.

        Any notice, demand, request, report or proxy material required or permitted to be given or made to record holders of our common units under the amended and restated partnership agreement will be delivered to the record holder by us or by the transfer agent.

        The annual meeting of the limited partners holding our common units will be held in June each year or on such other date and time as may be fixed from time to time by the General Partner. Notice of the annual meeting will be given between ten days and 60 days prior to the meeting date. The limited partners holding our common units will vote together as a single class. The limited partners entitled to vote will elect by plurality of the votes cast at such meeting the directors of the General Partner. Each of our common units is entitled to one vote for each of our common units that is registered in the name of the limited partner on the record date for the meeting. The General Partner, the Partnership or their affiliates cannot vote their units that they are otherwise entitled to vote, and those units are not considered to be outstanding for purposes of determining a quorum.

Board of Directors

        The number of directors of the General Partner board will be between seven and eleven, but the number of the directors may be changed by the majority of the directors of the General Partner board so long as the decrease in number does not shorten the term of any incumbent director. Unless otherwise previously elected at a special meeting, at each annual meeting of the limited partners, the directors will be elected to hold office until the next annual meeting. Each director will hold office for the term for which such director is elected or until such director's earlier death, resignation or removal. Any vacancies may be filled, until the next annual meeting, by a majority of the remaining directors then in office. A director may be removed only for cause and only upon a vote of the majority of the remaining directors then in office. If the SEC promulgates a rule that provides for nominations by the stockholders of publicly traded companies of persons for election to the board of directors, the Partnership and the General Partner will adopt such rule as applied to a corporation without regard to any exemptions provided to limited partnerships.

Status as Limited Partner or Assignee

        Except as described above under "—Limited Liability," our common units will be fully paid, and our unitholders will not be required to make additional contributions.

        An assignee of one of our common units, after executing and delivering a transfer application, but pending its admission as a substituted limited partner, is entitled to an interest equivalent to that of a limited partner for the right to share in allocations and distributions from us, including liquidating

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distributions. The General Partner will vote and exercise other powers attributable to our common units owned by an assignee that has not become a substitute limited partner at the written direction of the assignee. Please read "—Meetings; Voting" above. Transferees that do not execute and deliver a transfer application will not be treated as assignees nor as record holders of our common units, and will not receive cash distributions, federal income tax allocations or reports furnished to holders of our common units. Please read "Description of the Common Units—Transfer of Common Units."

Non-citizen Assignees; Redemption

        If the we are or become subject to federal, state or local laws or regulations that, in the reasonable determination of the General Partner, create a substantial risk of cancellation or forfeiture of any property that we have an interest in because of the nationality, citizenship or other related status of any limited partner or assignee, we may redeem the units held by the limited partner or assignee at their current market price. In order to avoid any cancellation or forfeiture, the General Partner may require each limited partner or assignee to furnish information about his nationality, citizenship or related status. If a limited partner or assignee fails to furnish information about his nationality, citizenship or other related status within 30 days after a request for the information or the General Partner determines, with the advice of counsel, after receipt of the information that the limited partner or assignee is not an eligible citizen, the limited partner or assignee may be treated as a non-citizen assignee and the General Partner will be substituted for such non citizen assignee as the limited partner in respect of his limited partner interests. In addition to other limitations on the rights of an assignee that is not a substituted limited partner, a non-citizen assignee does not have the right to direct the voting of his units and may not receive distributions in kind upon our liquidation.

Indemnification

        Under the amended and restated partnership agreement, in most circumstances, we will indemnify the following persons, to the fullest extent permitted by law, from and against all losses, claims, damages or similar events:

•

the General Partner;

•

any person who is or was an affiliate of the General Partner or any departing general partner;

•

any person who is or was a member, partner, officer, director, employee, agent or trustee of us, Opco, any of their subsidiaries, the General Partner or any affiliate of us, Opco or any of their subsidiaries; or

•

any person who is or was serving at the request of a general partner or any departing general partner or any affiliate of a general partner or any departing general partner as an officer, director, employee, member, partner, agent or trustee of another person.

        Any indemnification under these provisions will only be out of our assets. The General Partner and its affiliates will not be personally liable for, or have any obligation to contribute or loan funds or assets to us to enable us to effectuate indemnification. We may purchase insurance against liabilities asserted against and expenses incurred by persons in connection with our activities, regardless of whether we would have the power to indemnify the person against liabilities under the amended and restated partnership agreement.

Books and Reports

        The General Partner is required to keep appropriate books and records of our business at our principal offices. The books will be maintained for both tax and financial reporting purposes on an accrual basis. For tax and fiscal reporting purposes, our fiscal year is the calendar year.

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        We will furnish or make available to record holders of common units, within 120 days after the close of each fiscal year, an annual report containing audited financial statements and a report on those financial statements by our independent public accountants. Except for our fourth quarter, we will also furnish or make available summary financial information within 90 days after the close of each quarter.

        We will furnish each record holder of a unit with information reasonably required for tax reporting purposes within 90 days after the close of each calendar year. This information is expected to be furnished in summary form so that some complex calculations normally required of partners can be avoided. Our ability to furnish this summary information to unitholders will depend on the cooperation of unitholders in supplying us with specific information. Every unitholder will receive information to assist him in determining his federal and state tax liability and filing his federal and state income tax returns, regardless of whether he supplies us with information.

Right to Inspect the Partnership's Books and Records

        The amended and restated partnership agreement provides that a limited partner can, for a purpose reasonably related to his interest as a limited partner, upon reasonable written demand and at his own expense, have furnished to him:

•

a current list of the name and last known address of each limited partner;

•

a copy of our tax returns;

•

information as to the amount of cash, and a description and statement of the agreed value of any other property or services, contributed or to be contributed by each limited partner and the date on which each became a limited partner;

•

copies of the amended and restated partnership agreement, our certificate of limited partnership, related amendments and powers of attorney under which they have been executed;

•

information regarding the status of our business and financial condition; and

•

any other information regarding our affairs as is just and reasonable.

        The General Partner may, and intends to, keep confidential from the limited partners trade secrets or other information the disclosure of which the general partner believes in good faith is not in our or our subsidiaries' best interests, could damage us or our subsidiaries or which we or our subsidiaries are required by law or by agreements with third parties to keep confidential.

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MATERIAL TAX CONSEQUENCES

        This section is a summary of the material tax consequences that may be relevant to prospective unitholders who are individual citizens or residents of the United States and, unless otherwise noted in the following discussion, is the opinion of Vinson & Elkins L.L.P., counsel to our general partner and us, insofar as it relates to matters of United States federal income tax law and legal conclusions with respect to those matters. This section is based on current provisions of the Internal Revenue Code of 1986, as amended (the "Internal Revenue Code"), existing and proposed Treasury regulations (the "Treasury Regulations") to the extent noted and current administrative rulings and court decisions, all of which are subject to change. Later changes in these authorities may cause the tax consequences to vary substantially from the consequences described below. Unless the context otherwise requires, references in this section to "us" or "we" are to MarkWest Energy Partners and the operating partnership.

        This section does not address all federal income tax matters that affect us or the unitholders. Furthermore, this section focuses on unitholders who are individual citizens or residents of the United States and has only limited application to corporations, estates, trusts, non-resident aliens or other unitholders subject to specialized tax treatment, such as tax-exempt institutions, foreign persons, individual retirement accounts (IRAs), real estate investment trusts (REITs) or mutual funds. Accordingly, each prospective unitholder is urged to consult, and depend on, his own tax advisor in analyzing the federal, state, local and foreign tax consequences particular to him of the ownership or disposition of common units.

        All statements as to matters of law and legal conclusions, but not as to factual matters, contained in this section, unless otherwise noted, are the opinion of Vinson & Elkins L.L.P. and are based on the accuracy of the representations made by us.

        No ruling has been or will be requested from the IRS regarding any matter that affects us or prospective unitholders. Instead, we will rely on opinions and advice of Vinson & Elkins L.L.P. Unlike a ruling, an opinion of counsel represents only that counsel's best legal judgment and does not bind the IRS or the courts. Accordingly, the opinions and statements made herein may not be sustained by a court if contested by the IRS. Any contest of this sort with the IRS may materially and adversely impact the market for the common units and the prices at which common units trade. In addition, the costs of any contest with the IRS, principally legal, accounting and related fees, will result in a reduction in cash available for distribution to our unitholders and our general partner and thus will be borne directly or indirectly by the unitholders and the general partner. Furthermore, the tax treatment of us, or of an investment in us, may be significantly modified by future legislative or administrative changes or court decisions. Any modifications may or may not be retroactively applied.

        For the reasons described below, Vinson & Elkins L.L.P. has not rendered an opinion with respect to the following specific federal income tax issues:

        (1)   the treatment of a unitholder whose common units are loaned to a short seller to cover a short sale of common units (please read "—Tax Consequences of Unit Ownership—Treatment of Short Sales");

        (2)   whether our monthly convention for allocating taxable income and losses is permitted by existing Treasury Regulations (please read "—Disposition of Common Units—Allocations Between Transferors and Transferees"); and

        (3)   whether our method for depreciating Section 743 adjustments is sustainable in certain cases (please read "—Tax Consequences of Unit Ownership—Section 754 Election").

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Partnership Status

        A partnership is not a taxable entity and incurs no federal income tax liability. Instead, each partner of a partnership is required to take into account his share of items of income, gain, loss and deduction of the partnership in computing his federal income tax liability, even if no cash distributions are made to him by the partnership. Distributions by a partnership to a partner are generally not taxable to the partnership or the partner unless the amount of cash distributed to him is in excess of the partner's adjusted basis in his partnership interest.

        Section 7704 of the Internal Revenue Code provides that publicly traded partnerships will, as a general rule, be taxed as corporations. However, an exception, referred to as the "Qualifying Income Exception," exists with respect to publicly traded partnerships of which 90% or more of the gross income for every taxable year consists of "qualifying income." Qualifying income includes income and gains derived from the transportation, storage and processing of crude oil, natural gas and products thereof and fertilizer. Other types of qualifying income include interest (other than from a financial business), dividends, gains from the sale of real property and gains from the sale or other disposition of capital assets held for the production of income that otherwise constitutes qualifying income. We estimate that less than 4% of our current gross income is not qualifying income; however, this estimate could change from time to time. Based upon and subject to this estimate, the factual representations made by us and the general partner and a review of the applicable legal authorities, Vinson & Elkins L.L.P. is of the opinion that at least 90% of our current gross income constitutes qualifying income. The portion of our income that is qualifying may change from time to time.

        No ruling has been or will be sought from the IRS and the IRS has made no determination as to our status or the status of the operating partnership for federal income tax purposes or whether our operations generate "qualifying income" under Section 7704 of the Internal Revenue Code. Instead, we will rely on the opinion of Vinson & Elkins L.L.P. that, based on the Internal Revenue Code, its regulations, published revenue rulings and court decisions and the representations set forth below, MarkWest Energy Partners will be classified as a partnership for federal income tax purposes.

        In rendering its opinion, Vinson & Elkins L.L.P. has relied on factual representations made by us and the general partner. The representations made by us and our general partner upon which counsel has relied included:

        (a)   Neither we nor the operating partnership has elected or will elect to be treated as a corporation; and

        (b)   For each taxable year, more than 90% of our gross income has been and will be income that Vinson & Elkins L.L.P. has opined or will opine is "qualifying income" within the meaning of Section 7704(d) of the Internal Revenue Code; and

        (c)   Each hedging transaction that we treated as resulting in qualifying income has been and will be appropriately identified as a hedging transaction pursuant to applicable Treasury Regulations, and has been and will be associated with oil, gas, or products thereof that are held or to be held by us in activities that Vinson & Elkins L.L.P. has opined or will opine result in qualifying income.

        We believe that these representations have been true in the past and expect that these representations will be true in the future. If we fail to meet the Qualifying Income Exception, other than a failure that is determined by the IRS to be inadvertent and that is cured within a reasonable time after discovery, in which case the IRS may also require us to make adjustments with respect to our unitholders or pay other amounts, we will be treated as if we had transferred all of our assets, subject to liabilities, to a newly formed corporation, on the first day of the year in which we fail to meet the Qualifying Income Exception, in return for stock in that corporation, and then distributed that stock to the unitholders in liquidation of their interests in us. This deemed contribution and

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liquidation should be tax-free to unitholders and us so long as we, at that time, do not have liabilities in excess of the tax basis of our assets. Thereafter, we would be treated as a corporation for federal income tax purposes.

        If we were treated as an association taxable as a corporation in any taxable year, either as a result of a failure to meet the Qualifying Income Exception or otherwise, our items of income, gain, loss and deduction would be reflected only on our tax return rather than being passed through to the unitholders, and our net income would be taxed to us at corporate rates. In addition, any distribution made to a unitholder would be treated as either taxable dividend income, to the extent of our current or accumulated earnings and profits, or, in the absence of earnings and profits, a nontaxable return of capital, to the extent of the unitholder's tax basis in his common units, or taxable capital gain, after the unitholder's tax basis in his common units is reduced to zero. Accordingly, taxation as a corporation would result in a material reduction in a unitholder's cash flow and after-tax return and thus would likely result in a substantial reduction of the value of the units.

        The remainder of this section is based on Vinson & Elkins L.L.P.'s opinion that MarkWest Energy Partners will be classified as a partnership for federal income tax purposes.

Limited Partner Status

        Unitholders who have become limited partners of MarkWest Energy Partners will be treated as partners of MarkWest Energy Partners for federal income tax purposes. Also:

        (a)   assignees who have executed and delivered transfer applications, and are awaiting admission as limited partners, and

        (b)   unitholders whose common units are held in street name or by a nominee and who have the right to direct the nominee in the exercise of all substantive rights attendant to the ownership of their common units,

will be treated as partners of MarkWest Energy Partners for federal income tax purposes.

        As there is no direct or indirect controlling authority addressing the federal tax treatment of assignees of common units who are entitled to execute and deliver transfer applications and thereby become entitled to direct the exercise of attendant rights, but who fail to execute and deliver transfer applications, the opinion of Vinson & Elkins L.L.P. does not extend to these persons. Furthermore, a purchaser or other transferee of common units who does not execute and deliver a transfer application may not receive some federal income tax information or reports furnished to record holders of common units unless the common units are held in a nominee or street name account and the nominee or broker has executed and delivered a transfer application for those common units.

        A beneficial owner of common units whose units have been transferred to a short seller to complete a short sale would appear to lose his status as a partner with respect to those units for federal income tax purposes. Please read "—Tax Consequences of Unit Ownership—Treatment of Short Sales."

        Income, gain, deductions or losses would not appear to be reportable by a unitholder who is not a partner for federal income tax purposes, and any cash distributions received by a unitholder who is not a partner for federal income tax purposes would therefore appear to be fully taxable as ordinary income. These holders are urged to consult their own tax advisors with respect to their status as partners in MarkWest Energy Partners for federal income tax purposes.

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Tax Consequences of Unit Ownership

        Flow-Through of Taxable Income.    We will not pay any federal income tax. Instead, each unitholder will be required to report on his income tax return his share of our income, gains, losses and deductions without regard to whether corresponding cash distributions are received by him.

        Consequently, we may allocate income to a unitholder even if he has not received a cash distribution. Each unitholder will be required to include in income his allocable share of our income, gains, losses and deductions for our taxable year ending with or within his taxable year. Our taxable year ends on December 31.

        Treatment of Distributions.    Cash distributions made by us to a unitholder generally will not be taxable to him for federal income tax purposes, except to the extent the amount of any such cash distribution exceeds his tax basis in his common units immediately before the distribution. Cash distributions made by us to a unitholder in an amount in excess of his tax basis in his common units generally will be considered to be gain from the sale or exchange of the common units, taxable in accordance with the rules described under "—Disposition of Common Units" below. To the extent that cash distributions made by us cause a unitholder's "at risk" amount to be less than zero at the end of any taxable year, he must recapture any losses deducted in previous years. Please read "—Limitations on Deductibility of Losses."

        Any reduction in a unitholder's share of our liabilities for which no partner, including the general partner, bears the economic risk of loss, known as "nonrecourse liabilities," will be treated as a distribution of cash to that unitholder. A decrease in a unitholder's percentage interest in us because of our issuance of additional common units will decrease his share of our nonrecourse liabilities, and thus will result in a corresponding deemed distribution of cash. This deemed distribution may constitute a non-pro rata distribution. A non-pro rata distribution of money or property may result in ordinary income to a unitholder, regardless of his tax basis in his common units, if the distribution reduces the unitholder's share of our "unrealized receivables," including depreciation recapture, and/or substantially appreciated "inventory items," both as defined in Section 751 of the Internal Revenue Code, and collectively, "Section 751 Assets." To that extent, he will be treated as having received his proportionate share of the Section 751 Assets and having exchanged those assets with us in return for the non-pro rata portion of the actual distribution made to him. This latter deemed exchange will generally result in the unitholder's realization of ordinary income. That income will equal the excess of (1) the non-pro rata portion of that distribution over (2) the unitholder's tax basis (generally zero) for the share of Section 751 Assets deemed relinquished in the exchange.

        Basis of Common Units.    A unitholder's initial tax basis for his common units will be the amount he paid for the common units plus his share of our nonrecourse liabilities. That basis will be increased by his share of our income and by any increases in his share of our nonrecourse liabilities. That basis will be decreased, but not below zero, by distributions to him from us, by his share of our losses, by any decreases in his share of our nonrecourse liabilities and by his share of our expenditures that are not deductible in computing taxable income and are not required to be capitalized. A unitholder will have no share of our debt that is recourse to the general partner, but will have a share, generally based on his share of profits, of our nonrecourse liabilities. Please read "—Disposition of Common Units—Recognition of Gain or Loss."

        Limitations on Deductibility of Losses.    The deduction by a unitholder of his share of our losses will be limited to the tax basis in his units and, in the case of an individual unitholder estate, trust or a corporate unitholder (if more than 50% of the value of the corporate unitholder's stock is owned directly or indirectly by or for five or fewer individuals or certain tax-exempt organizations), to the amount for which the unitholder is considered to be "at risk" with respect to our activities, if that is less than his tax basis. A unitholder must recapture losses deducted in previous years to the extent that distributions cause his at-risk amount to be less than zero at the end of any taxable year. Losses disallowed to a unitholder

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or recaptured as a result of these limitations will carry forward and will be allowable as a deduction in a later year to the extent that his at-risk amount is subsequently increased, provided such losses do not exceed such common unitholder's tax basis in common units. Upon the taxable disposition of a unit, any gain recognized by a unitholder can be offset by losses that were previously suspended by the at risk limitation but may not be offset by losses suspended by the basis limitation. Any loss suspended by the at risk or basis limitation in excess of that gain is no longer utilizable.

        In general, a unitholder will be at risk to the extent of his tax basis in his units, excluding any portion of that basis attributable to his share of our nonrecourse liabilities, reduced by (i) any portion of that basis representing amounts otherwise protected against loss because of a guarantee, stop loss agreement or other similar arrangement and (ii) any amount of money he borrows to acquire or hold his units, if the lender of those borrowed funds owns an interest in us, is related to the unitholder or can look only to the units for repayment. A unitholder's at-risk amount will increase or decrease as the tax basis of the unitholder's units increases or decreases, other than tax basis increases or decreases attributable to increases or decreases in his share of our nonrecourse liabilities.

        In addition to the basis and at-risk limitation on the deductability of losses, the passive loss limitations generally provide that individuals, estates, trusts and some closely-held corporations and personal service corporations are permitted to deduct losses from passive activities, which are generally defined as trade or business activities in which the taxpayer does not materially participate, only to the extent of the taxpayer's income from those passive activities. The passive loss limitations are applied separately with respect to each publicly traded partnership. Consequently, any passive losses we generate will only be available to offset our passive income generated in the future and will not be available to offset income from other passive activities or investments, including our investments or a unitholder's investments in other publicly traded partnerships, or salary or active business income. Similarly, a unitholder's share of our net income may not be offset by any other current or carryover losses from other passive activities, including those attributable to other publicly traded partnerships. Passive losses that are not deductible because they exceed a unitholder's share of income we generate may be deducted in full when he disposes of his entire investment in us in a fully taxable transaction with an unrelated party. The passive activity loss rules are applied after other applicable limitations on deductions, including the at-risk rules and the basis limitation.

        Limitations on Interest Deductions.    The deductibility of a non-corporate taxpayer's "investment interest expense" is generally limited to the amount of that taxpayer's "net investment income." Investment interest expense includes:

•

interest on indebtedness properly allocable to property held for investment;

•

our interest expense attributable to portfolio income; and

•

the portion of interest expense incurred to purchase or carry an interest in a passive activity to the extent attributable to portfolio income.

        The computation of a unitholder's investment interest expense will take into account interest on any margin account borrowing or other loan incurred to purchase or carry a unit. Net investment income includes gross income from property held for investment and amounts treated as portfolio income under the passive loss rules, less deductible expenses, other than interest, directly connected with the production of investment income, but generally does not include gains attributable to the disposition of property held for investment or qualified dividend income. The IRS has indicated that net passive income earned by a publicly traded partnership will be treated as investment income to its unitholders. In addition, the unitholder's share of our portfolio income will be treated as investment income.

        Entity Level Collections.    If we are required or elect under applicable law to pay any federal, state, local or foreign income tax on behalf of any unitholder or the general partner or any former unitholder, we are authorized to pay those taxes from our funds. That payment, if made, will be treated

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as a distribution of cash to the unitholder on whose behalf the payment was made. If the payment is made on behalf of a unitholder whose identity cannot be determined, we are authorized to treat the payment as a distribution to all current unitholders. We are authorized to amend the partnership agreement in the manner necessary to maintain uniformity of intrinsic tax characteristics of units and to adjust later distributions, so that after giving effect to these distributions, the priority and characterization of distributions otherwise applicable under the partnership agreement is maintained as nearly as is practicable. Payments by us as described above could give rise to an overpayment of tax on behalf of a unitholder in which event the unitholder would be required to file a claim in order to obtain a credit or refund.

        Allocation of Income, Gain, Loss and Deduction.    In general, if we have a net profit, our items of income, gain, loss and deduction will be allocated among the unitholders in accordance with their percentage interests in us. If we have a net loss for the entire year, that amount of loss will be allocated among the unitholders in accordance with their percentage interests.

        Specified items of our income, gain, loss and deduction will be allocated to account for the difference between the tax basis and fair market value of our assets at the time of an offering, referred to in this discussion as the "Contributed Property." The effect of these allocations, referred to as Section 704(c) Allocations, to a unitholder acquiring common units from us in an offering or in connection with a contribution of property will be essentially the same as if the tax basis of our assets were equal to their fair market value at the time of such offering or other transaction. In the event we issue additional common units or engage in certain other transactions in the future "reverse Section 704(c) Allocations," similar to Section 704(c) Allocations described above, will be made to holders of partnership immediately prior to such other transactions to account for the difference between the "book" basis for purposes of maintaining capital accounts and the fair market value of all property held by us at the time of the future transaction. In addition, items of recapture income will be allocated to the extent possible to the unitholder who was allocated the deduction giving rise to the treatment of that gain as recapture income in order to minimize the recognition of ordinary income by other unitholders. Finally, although we do not expect that our operations will result in the creation of negative capital accounts, if negative capital accounts nevertheless result, items of our income and gain will be allocated in an amount and manner sufficient to eliminate the negative balance as quickly as possible.

        An allocation of items of our income, gain, loss or deduction, other than an allocation required by the Internal Revenue Code to eliminate the difference between a partner's "book" capital account, credited with the fair market value of Contributed Property, and "tax" capital account, credited with the tax basis of Contributed Property, referred to in this discussion as the "Book-Tax Disparity," will generally be given effect for federal income tax purposes in determining a partner's share of an item of income, gain, loss or deduction only if the allocation has substantial economic effect. In any other case, a partner's share of an item will be determined on the basis of his interest in us, which will be determined by taking into account all the facts and circumstances, including:

•

his relative contributions to us;

•

the interests of all the partners in profits and losses;

•

the interest of all the partners in cash flow; and

•

the rights of all the partners to distributions of capital upon liquidation.

        Vinson & Elkins L.L.P. is of the opinion that, with the exception of the issues described in "—Section 754 Election" and "—Disposition of Common Units—Allocations Between Transferors and Transferees," allocations under our partnership agreement will be given effect for federal income tax purposes in determining a unitholder's share of an item of income, gain, loss or deduction.

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        Treatment of Short Sales.    A unitholder whose units are loaned to a "short seller" to cover a short sale of units may be considered as having disposed of those units. If so, he would no longer be treated for tax purposes as a partner with respect to those units during the period of the loan and may recognize gain or loss from the disposition. As a result, during this period:

•

any of our income, gain, loss or deduction with respect to those units would not be reportable by the unitholder;

•

any cash distributions received by the unitholder as to those units would be fully taxable; and

•

all of these distributions would appear to be ordinary income.

        Vinson & Elkins L.L.P. has not rendered an opinion regarding the tax treatment of a unitholder where common units are loaned to a short seller to cover a short sale of common units; therefore, unitholders desiring to assure their status as partners and avoid the risk of gain recognition from a loan to a short seller should modify any applicable brokerage account agreements to prohibit their brokers from borrowing and loaning their units. The IRS has announced that it is actively studying issues relating to the tax treatment of short sales of partnership interests. Please also read "—Disposition of Common Units—Recognition of Gain or Loss."

        Alternative Minimum Tax.    Each unitholder will be required to take into account his distributive share of any items of our income, gain, loss or deduction for purposes of the alternative minimum tax. The current minimum tax rate for noncorporate taxpayers is 26% on the first $175,000 of alternative minimum taxable income in excess of the exemption amount and 28% on any additional alternative minimum taxable income. Prospective unitholders are urged to consult with their tax advisors as to the impact of an investment in units on their liability for the alternative minimum tax.

        Tax Rates.    Under current law, the highest marginal U.S. federal income tax rate applicable to ordinary income of individuals is 35% and the highest marginal U.S. federal income tax rate applicable to long-term capital gains (generally, capital gains on certain assets held for more than 12 months) of individuals is 15%. However, absent new legislation extending the current rates, beginning January 1, 2011, the highest marginal U.S. federal income tax rate applicable to ordinary income and long-term capital gains of individuals will increase to 39.6% and 20%, respectively.

        Section 754 Election.    We have made the election permitted by Section 754 of the Internal Revenue Code. That election is irrevocable without the consent of the IRS. The election will generally permit us to adjust a common unit purchaser's tax basis in our assets ("inside basis") under Section 743(b) of the Internal Revenue Code to reflect his purchase price. The Section 743(b) adjustment does not apply to a person who purchases common units directly from us and it belongs only to the purchaser and not to other unitholders. Please also read, however, "—Tax Consequences of Unit Ownership—Allocation of Income, Gain, Loss and Deduction." For purposes of this discussion, a unitholder's inside basis in our assets has two components: (1) his share of our tax basis in our assets ("common basis") and (2) his Section 743(b) adjustment to that basis.

        Where the remedial allocation method is adopted (which we have adopted as to all property), the Treasury Regulations under Section 743 of the Internal Revenue Code require a portion of the Section 743(b) adjustment that is attributable to recovery property subject to depreciation under Section 168 of the Internal Revenue Code whose book basis is in excess of its tax basis to be depreciated over the remaining cost recovery period for the property's unamortized Book-Tax Disparity. Under Treasury Regulation Section 1.167(c)-l(a)(6), a Section 743(b) adjustment attributable to property subject to depreciation under Section 167 of the Internal Revenue Code rather than cost recovery deductions under Section 168 is generally required to be depreciated using either the straight-line method or the 150% declining balance method. Under our partnership agreement, the general partner is authorized to take a position to preserve the uniformity of units even if that position

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is not consistent with these Treasury Regulations. Please read "—Tax Treatment of Operations—Uniformity of Units."

        Although Vinson & Elkins L.L.P. is unable to opine as to the validity of this approach because there is no direct or indirect controlling authority on this issue, we intend to depreciate the portion of a Section 743(b) adjustment attributable to unrealized appreciation in the value of Contributed Property, to the extent of any unamortized Book-Tax Disparity, using a rate of depreciation or amortization derived from the depreciation or amortization method and useful life applied to the property's unamortized Book-Tax Disparity, or treat that portion as non-amortizable to the extent attributable to property the common basis of which is not amortizable. This method is consistent with the methods employed by other publicly traded partnerships but is arguably inconsistent with Treasury Regulation Section 1.167(c)-1(a)(6), which is not expected to directly apply to a material portion of our assets and Treasury Regulation Section 1.197-2(g)(3). To the extent this Section 743(b) adjustment is attributable to appreciation in value in excess of the unamortized Book-Tax Disparity, we will apply the rules described in the Treasury Regulations and legislative history. If we determine that this position cannot reasonably be taken, we may take a depreciation or amortization position under which all purchasers acquiring units in the same month would receive depreciation or amortization, whether attributable to common basis or a Section 743(b) adjustment, based upon the same applicable rate as if they had purchased a direct interest in our assets. This kind of aggregate approach may result in lower annual depreciation or amortization deductions than would otherwise be allowable to some unitholders. Please read "—Tax Treatment of Operations—Uniformity of Units." A unitholder's tax basis for his common units is reduced by his share of our deductions (whether or not such deductions were claimed on an individual's income tax return) so that any position we take that understates deductions will overstate the common unitholder's basis in his common units, which may cause the unitholder to understate gain or overstate loss on any sale of such units. Please read "—Disposition of Common Units—Recognition of Gain or Loss." The IRS may challenge our position with respect to depreciating or amortizing the Section 743(b) adjustment we take to preserve the uniformity of the units. If such a challenge were sustained, the gain from the sale of units might be increased without the benefit of additional deductions.

        A Section 754 election is advantageous if the transferee's tax basis in his units is higher than the units' share of the aggregate tax basis of our assets immediately prior to the transfer. In that case, as a result of the election, the transferee would have, among other items, a greater amount of depreciation and depletion deductions and his share of any gain or loss on a sale of our assets would be less. Conversely, a Section 754 election is disadvantageous if the transferee's tax basis in his units is lower than those units' share of the aggregate tax basis of our assets immediately prior to the transfer. Thus, the fair market value of the units may be affected either favorably or unfavorably by the election. A basis adjustment is required regardless of whether a Section 754 election is made in the case of a transfer of an interest in us if we have a substantial built-in loss immediately after the transfer, or if we distribute property and have a substantial basis reduction. Generally a built-in loss or a basis reduction is substantial if it exceeds $250,000.

        The calculations involved in the Section 754 election are complex and will be made on the basis of assumptions as to the value of our assets and other matters. For example, the allocation of the Section 743(b) adjustment among our assets must be made in accordance with the Internal Revenue Code. The IRS could seek to reallocate some or all of any Section 743(b) adjustment allocated by us to our tangible assets to goodwill instead. Goodwill, as an intangible asset, is generally amortizable over a longer period of time or under a less accelerated method than our tangible assets. We cannot assure you that the determinations we make will not be successfully challenged by the IRS and that the deductions resulting from them will not be reduced or disallowed altogether. Should the IRS require a different basis adjustment to be made, and should, in our opinion, the expense of compliance exceed the benefit of the election, we may seek permission from the IRS to revoke our Section 754 election. If

35

permission is granted, a subsequent purchaser of units may be allocated more income than he would have been allocated had the election not been revoked.

Tax Treatment of Operations

        Accounting Method and Taxable Year.    We use the year ending December 31 as our taxable year and the accrual method of accounting for federal income tax purposes. Each unitholder will be required to include in income his share of our income, gain, loss and deduction for our taxable year ending within or with his taxable year. In addition, a unitholder who has a taxable year ending on a date other than December 31 and who disposes of all of his units following the close of our taxable year but before the close of his taxable year must include his share of our income, gain, loss and deduction in income for his taxable year, with the result that he will be required to include in income for his taxable year his share of more than twelve months of our income, gain, loss and deduction. Please read "—Disposition of Common Units—Allocations Between Transferors and Transferees."

        Tax Basis, Depreciation and Amortization.    The tax basis of our assets will be used for purposes of computing depreciation and cost recovery deductions and, ultimately, gain or loss on the disposition of these assets. The federal income tax burden associated with the difference between the fair market value of our assets and their tax basis immediately prior to any offering will be borne by our unitholders as of that time. Please read "—Tax Consequences of Unit Ownership—Allocation of Income, Gain, Loss and Deduction."

        To the extent allowable, we may elect to use the depreciation and cost recovery methods that will result in the largest deductions being taken in the early years after assets subject to these allowances are placed in service. We were not entitled to any amortization deductions with respect to any goodwill conveyed to us on formation. Property we subsequently acquire or construct may be depreciated using accelerated methods permitted by the Internal Revenue Code.

        If we dispose of depreciable property by sale, foreclosure, or otherwise, all or a portion of any gain, determined by reference to the amount of depreciation previously deducted and the nature of the property, may be subject to the recapture rules and taxed as ordinary income rather than capital gain. Similarly, a partner who has taken cost recovery or depreciation deductions with respect to property we own will likely be required to recapture some or all of those deductions as ordinary income upon a sale of his interest in us. Please read "—Tax Consequences of Unit Ownership—Allocation of Income, Gain, Loss and Deduction" and "—Disposition of Common Units—Recognition of Gain or Loss."

        The costs incurred in selling our units (called "syndication expenses") must be capitalized and cannot be deducted currently, ratably or upon our termination. There are uncertainties regarding the classification of costs as organization expenses, which we may amortize, and as syndication expenses, which we may not amortize. The underwriting discounts and commissions we incur will be treated as syndication expenses.

        Valuation and Tax Basis of Our Properties.    The federal income tax consequences of the ownership and disposition of units will depend in part on our estimates of the relative fair market values, and the initial tax bases, of our assets. Although we may from time to time consult with professional appraisers regarding valuation matters, we will make many of the relative fair market value estimates ourselves. These estimates and determinations of basis are subject to challenge and will not be binding on the IRS or the courts. If the estimates of fair market value or basis are later found to be incorrect, the character and amount of items of income, gain, loss or deductions previously reported by unitholders might change, and unitholders might be required to adjust their tax liability for prior years and incur interest and penalties with respect to those adjustments.

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Disposition of Common Units

        Recognition of Gain or Loss.    Gain or loss will be recognized on a sale of units equal to the difference between the amount realized and the unitholder's tax basis for the units sold. A unitholder's amount realized will be measured by the sum of the cash or the fair market value of other property he receives plus his share of our nonrecourse liabilities. Because the amount realized includes a unitholder's share of our nonrecourse liabilities, the gain recognized on the sale of units could result in a tax liability in excess of any cash received from the sale.

        Prior distributions from us in excess of cumulative net taxable income for a common unit that decreased a unitholder's tax basis in that common unit will, in effect, become taxable income if the common unit is sold at a price greater than the unitholder's tax basis in that common unit, even if the price received is less than his original cost.

        Except as noted below, gain or loss recognized by a unitholder, other than a "dealer" in units, on the sale or exchange of a unit held for more than one year will generally be taxable as long-term capital gain or loss. Capital gain recognized by an individual on the sale of units held more than twelve months will generally be taxed at a maximum U.S. federal income tax rate of 15% through December 31, 2010 and 20% thereafter (absent new legislation extending the current rate). However, a portion of this gain or loss, which will likely be substantial, however, will be separately computed and taxed as ordinary income or loss under Section 751 of the Internal Revenue Code to the extent attributable to assets giving rise to depreciation recapture or other "unrealized receivables" or to "inventory items" we own. The term "unrealized receivables" includes potential recapture items, including depreciation recapture. Ordinary income attributable to unrealized receivables, inventory items and depreciation recapture may exceed net taxable gain realized upon the sale of a unit and may be recognized even if there is a net taxable loss realized on the sale of a unit. Thus, a unitholder may recognize both ordinary income and a capital loss upon a sale of units. Net capital loss may offset capital gains and no more than $3,000 of ordinary income, in the case of individuals, and may only be used to offset capital gain in the case of corporations.

        The IRS has ruled that a partner who acquires interests in a partnership in separate transactions must combine those interests and maintain a single adjusted tax basis for all those interests. Upon a sale or other disposition of less than all of those interests, a portion of that tax basis must be allocated to the interests sold using an "equitable apportionment" method, which generally means that the tax basis allocated to the interest sold equals an amount that bears the same relation to the partner's tax basis in his entire interest in the partnership as the value of interest sold bears to the value of the partner's entire interest in the partnership. Treasury Regulations under Section 1223 of the Internal Revenue Code allow a selling unitholder who can identify common units transferred with an ascertainable holding period to elect to use the actual holding period of the common units transferred. Thus, according to the ruling, a common unitholder will be unable to select high or low basis common units to sell as would be the case with corporate stock, but, according to the Treasury Regulations, may designate specific common units sold for purposes of determining the holding period of units transferred. A unitholder electing to use the actual holding period of common units transferred must consistently use that identification method for all subsequent sales or exchanges of common units. A unitholder considering the purchase of additional units or a sale of common units purchased in separate transactions is urged to consult his tax advisor as to the possible consequences of this ruling and application of the Treasury Regulations.

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        Specific provisions of the Internal Revenue Code affect the taxation of some financial products and securities, including partnership interests, by treating a taxpayer as having sold an "appreciated" partnership interest, one in which gain would be recognized if it were sold, assigned or terminated at its fair market value, if the taxpayer or related persons enter(s) into:

•

a short sale;

•

an offsetting notional principal contract; or

•

a futures or forward contract with respect to the partnership interest or substantially identical property.

        Moreover, if a taxpayer has previously entered into a short sale, an offsetting notional principal contract or a futures or forward contract with respect to the partnership interest, the taxpayer will be treated as having sold that position if the taxpayer or a related person then acquires the partnership interest or substantially identical property. The Secretary of Treasury is also authorized to issue regulations that treat a taxpayer that enters into transactions or positions that have substantially the same effect as the preceding transactions as having constructively sold the financial position.

        Allocations Between Transferors and Transferees.    In general, our taxable income and losses will be determined annually, will be prorated on a monthly basis and will be subsequently apportioned among the unitholders in proportion to the number of units owned by each of them as of the opening of the applicable exchange on the first business day of the month (the "Allocation Date"). However, gain or loss realized on a sale or other disposition of our assets other than in the ordinary course of business will be allocated among the unitholders on the Allocation Date in the month in which that gain or loss is recognized. As a result, a unitholder transferring units may be allocated income, gain, loss and deduction realized after the date of transfer.

        Although simplifying conventions are contemplated by the Internal Revenue Code and most publicly traded partnerships use similar simplifying conventions, the use of this method may not be permitted under existing Treasury Regulations. Recently, however, the Department of the Treasury and the IRS issued proposed Treasury Regulations that provide a safe harbor pursuant to which a publicly traded partnership may use a similar monthly simplifying convention to allocate tax items among transferor and transferee unitholders, although such tax items must be prorated on a daily basis. Existing publicly traded partnerships are entitled to rely on these proposed Treasury Regulations; however, they are not binding on the IRS and are subject to change until final Treasury Regulations are issued. Accordingly, Vinson & Elkins L.L.P. is unable to opine on the validity of this method of allocating income and deductions between transferor and transferee unitholders. If this method is not allowed under the Treasury Regulations, or only applies to transfers of less than all of the unitholder's interest, our taxable income or losses might be reallocated among the unitholders. We are authorized to revise our method of allocation between transferor and transferee unitholders as well as unitholders whose interest may vary during a taxable year, to conform to a method permitted under future Treasury Regulations.

        A unitholder who owns units at any time during a quarter and who disposes of them prior to the record date set for a cash distribution for that quarter will be allocated items of our income, gain, loss and deductions attributable to that quarter but will not be entitled to receive that cash distribution.

        Notification Requirements.    A unitholder who sells any of his units is generally required to notify us in writing of that sale within 30 days after the sale (or, if earlier, January 15 of the year following the sale). A purchaser of units who purchases units from another unitholder is also generally required to notify us in writing of that purchase within 30 days after the purchase. Upon receiving such notifications, we are required to notify the IRS of that transaction and to furnish specified information to the transferor and transferee. Failure to notify us of a purchase may, in some cases, lead to the imposition of substantial penalties. However, these reporting requirements do not apply to a sale by an

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individual who is a citizen of the United States and who effects the sale or exchange through a broker who will satisfy such requirements.

        Constructive Termination.    We will be considered to have been terminated for tax purposes if there are sales or exchanges which, in the aggregate, constitute 50% or more of the total interests in our capital and profits within a twelve month period. For purposes of measuring whether the 50% threshold is reached, multiple sales of the same interest are counted only once. A constructive termination results in the closing of our taxable year for all unitholders. In the case of a unitholder reporting on a taxable year other than a fiscal year ending December 31, the closing of our taxable year may result in more than twelve months of our taxable income or loss being includable in his taxable income for the year of termination. A constructive termination occurring on a date other than December 31 will result in us filing two tax returns (and unitholders receiving two Schedules K-1) for one fiscal year and the cost of the preparation of these returns will be borne by all unitholders. We would be required to make new tax elections after a termination, including a new election under Section 754 of the Internal Revenue Code, and a termination would result in a deferral of our deductions for depreciation. A termination could also result in penalties if we were unable to determine that the termination had occurred. Moreover, a termination might either accelerate the application of, or subject us to, any tax legislation enacted before the termination. The IRS has announced recently that it plans to issue guidance regarding the treatment of constructive terminations of publicly traded partnerships such as us. Any such guidance may change the application of the rules discussed above and may affect the tax treatment of a unitholder.

Uniformity of Units

        Because we cannot match transferors and transferees of units, we must maintain uniformity of the economic and tax characteristics of the units to a purchaser of these units. In the absence of uniformity, we may be unable to completely comply with a number of federal income tax requirements, both statutory and regulatory. A lack of uniformity can result from a literal application of Treasury Regulation Section 1.167(c)-1(a)(6) and Treasury Regulation Section 1.197-2(g)(3). Any non-uniformity could have a negative impact on the value of the units. Please read "—Tax Consequences of Unit Ownership—Section 754 Election."

        We intend to depreciate the portion of a Section 743(b) adjustment attributable to unrealized appreciation in the value of Contributed Property, to the extent of any unamortized Book-Tax Disparity, using a rate of depreciation or amortization derived from the depreciation or amortization method and useful life applied to the property's unamortized Book-Tax Disparity, or treat that portion as nonamortizable, to the extent attributable to property the common basis of which is not amortizable, consistent with the Treasury Regulations under Section 743 of the Internal Revenue Code, even though that position may be inconsistent with Treasury Regulation Section 1.167(c)-1(a)(6) which is not expected to directly apply to a material portion of our assets and Treasury Regulation Section 1.197-2(g)(3). Please read "—Tax Consequences of Unit Ownership—Section 754 Election." To the extent that the Section 743(b) adjustment is attributable to appreciation in value in excess of the unamortized Book-Tax Disparity, we will apply the rules described in the Treasury Regulations and legislative history. If we determine that this position cannot reasonably be taken, we may adopt a depreciation and amortization position under which all purchasers acquiring units in the same month would receive depreciation and amortization deductions, whether attributable to a common basis or Section 743(b) adjustment, based upon the same applicable methods and lives as if they had purchased a direct interest in our property. If this position is adopted, it may result in lower annual depreciation and amortization deductions than would otherwise be allowable to some unitholders and risk the loss of depreciation and amortization deductions not taken in the year that these deductions are otherwise allowable. This position will not be adopted if we determine that the loss of depreciation and amortization deductions will have a material adverse effect on the unitholders. If we choose not to

39

utilize this aggregate method, we may use any other reasonable depreciation and amortization method to preserve the uniformity of the intrinsic tax characteristics of any units that would not have a material adverse effect on the unitholders. The IRS may challenge any method of depreciating the Section 743(b) adjustment described in this paragraph. If this challenge were sustained, the uniformity of units might be affected, and the gain from the sale of units might be increased without the benefit of additional deductions. Please read "—Disposition of Common Units—Recognition of Gain or Loss."

Tax-Exempt Organizations and Other Investors

        Ownership of units by employee benefit plans, other tax-exempt organizations, non-resident aliens, foreign corporations, and other foreign persons raises issues unique to those investors and, as described below, may have substantially adverse tax consequences to them. If you are a tax-exempt entity or a foreign person, you should consult your tax advisor before investing in our common units.

        Employee benefit plans and most other organizations exempt from federal income tax, including individual retirement accounts and other retirement plans, are subject to federal income tax on unrelated business taxable income. Virtually all of our income allocated to a unitholder which is a tax-exempt organization will be unrelated business taxable income and will be taxable to them.

        Non-resident aliens and foreign corporations, trusts or estates that own units will be considered to be engaged in business in the United States because of the ownership of units. As a consequence, they will be required to file federal tax returns to report their share of our income, gain, loss or deduction and pay federal income tax at regular rates on their share of our net income or gain. Under rules applicable to publicly traded partnerships, distributions to any such foreign unitholder will be subject to U.S. withholding at the highest effective applicable rate. Each foreign unitholder must obtain a taxpayer identification number from the IRS and submit that number to our transfer agent on a Form W-8BEN or applicable substitute form in order to obtain credit for these withholding taxes. A change in applicable law may require us to change these procedures.

        In addition, because a foreign corporation that owns units will be treated as engaged in a United States trade or business, that corporation may be subject to the United States branch profits tax at a rate of 30%, in addition to regular federal income tax, on its share of our income and gain, as adjusted for changes in the foreign corporation's "U.S. net equity," which is effectively connected with the conduct of a United States trade or business. That tax may be reduced or eliminated by an income tax treaty between the United States and the country in which the foreign corporate unitholder is a "qualified resident." In addition, this type of unitholder is subject to special information reporting requirements under Section 6038C of the Internal Revenue Code.

        A foreign unitholder who sells or otherwise disposes of a unit will be subject to U.S. federal income tax on gain realized from the sale or disposition of that unit to the extent the gain is effectively connected with a U.S. trade or business of the foreign unitholder. Under a ruling published by the IRS, interpreting the scope of "effective connected income," a foreign unitholder would be considered to be engaged in a trade or business in the U.S. by virtue of the U.S. activities of the partnership, and part or all of that unitholder's gain would be effectively connected with the unitholder's indirect U.S. trade or business. Moreover, under the Foreign Investment in Real Property Tax Act, a foreign unitholder of a publicly traded partnership generally will be subject to U.S. federal income tax upon the sale or disposition of a unit to the extent of the unitholder's share of the partnership's U.S. real property holdings if (i) he owned (directly or constructively applying certain attribution rules) more than 5% of the units at any time during the five-year period ending on the date of such disposition and (ii) 50% or more of the fair market value of all of our assets consisted of U.S. real property interests at any time during the shorter of the period during which such unitholder held the units or the 5-year period ending on the date of disposition. Currently, more than 50% of our assets consist of U.S. real property

40

interests and we do not expect that to change in the foreseeable future. Therefore, foreign unitholders may be subject to federal income tax on the gain from the sale or disposition of their units.

Administrative Matters

        Information Returns and Audit Procedures.    We intend to furnish to each unitholder, within 90 days after the close of each calendar year, specific tax information, including a Schedule K-1, which describes his share of our income, gain, loss and deduction for our preceding taxable year. In preparing this information, which will not be reviewed by counsel, we will take various accounting and reporting positions, some of which have been mentioned earlier, to determine his share of income, gain, loss and deduction. We cannot assure you that those positions will yield a result that conforms to the requirements of the Internal Revenue Code, Treasury Regulations or administrative interpretations of the IRS. Neither we nor Vinson & Elkins L.L.P. can assure prospective unitholders that the IRS will not successfully contend in court that those positions are impermissible. Any challenge by the IRS could negatively affect the value of the units.

        The IRS may audit our federal income tax information returns. Adjustments resulting from an IRS audit may require each unitholder to adjust a prior year's tax liability, and possibly may result in an audit of his own return. Any audit of a unitholder's return could result in adjustments not related to our returns as well as those related to our returns.

        Partnerships generally are treated as separate entities for purposes of federal tax audits, judicial review of administrative adjustments by the IRS and tax settlement proceedings. The tax treatment of partnership items of income, gain, loss and deduction are determined in a partnership proceeding rather than in separate proceedings with the partners. The Internal Revenue Code requires that one partner be designated as the "Tax Matters Partner" for these purposes. The partnership agreement names MarkWest Energy GP, L.L.C. as our Tax Matters Partner.

        The Tax Matters Partner will make some elections on our behalf and on behalf of unitholders. In addition, the Tax Matters Partner can extend the statute of limitations for assessment of tax deficiencies against unitholders for items in our returns. The Tax Matters Partner may bind a unitholder with less than a 1% profits interest in us to a settlement with the IRS unless that unitholder elects, by filing a statement with the IRS, not to give that authority to the Tax Matters Partner. The Tax Matters Partner may seek judicial review, by which all the unitholders are bound, of a final partnership administrative adjustment and, if the Tax Matters Partner fails to seek judicial review, judicial review may be sought by any unitholder having at least a 1% interest in profits or by any group of unitholders having in the aggregate at least a 5% interest in profits. However, only one action for judicial review will go forward, and each unitholder with an interest in the outcome may participate.

        A unitholder must file a statement with the IRS identifying the treatment of any item on his federal income tax return that is not consistent with the treatment of the item on our return. Intentional or negligent disregard of this consistency requirement may subject a unitholder to substantial penalties.

        Nominee Reporting.    Persons who hold an interest in us as a nominee for another person are required to furnish to us:

        (a)   the name, address and taxpayer identification number of the beneficial owner and the nominee;

        (b)   whether the beneficial owner is

        (1)   a person that is not a United States person,

        (2)   a foreign government, an international organization or any wholly owned agency or instrumentality of either of the foregoing, or

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        (3)   a tax-exempt entity;

        (c)   the amount and description of units held, acquired or transferred for the beneficial owner; and

        (d)   specific information including the dates of acquisitions and transfers, means of acquisitions and transfers, and acquisition cost for purchases, as well as the amount of net proceeds from sales.

        Brokers and financial institutions are required to furnish additional information, including whether they are United States persons and specific information on units they acquire, hold or transfer for their own account. A penalty of $50 per failure, up to a maximum of $100,000 per calendar year, is imposed by the Internal Revenue Code for failure to report that information to us. The nominee is required to supply the beneficial owner of the units with the information furnished to us.

        Accuracy Related Penalties.    An additional tax equal to 20% of the amount of any portion of an underpayment of tax that is attributable to one or more specified causes, including negligence or disregard of rules or regulations, substantial understatements of income tax and substantial valuation misstatements, is imposed by the Internal Revenue Code. No penalty will be imposed, however, for any portion of an underpayment if it is shown that there was a reasonable cause for that portion and that the taxpayer acted in good faith regarding that portion.

        For individuals a substantial understatement of income tax in any taxable year exists if the amount of the understatement exceeds the greater of 10% of the tax required to be shown on the return for the taxable year or $5,000. The amount of any understatement subject to penalty generally is reduced if any portion is attributable to a position adopted on the return:

        (1)   for which there is, or was, "substantial authority," or

        (2)   as to which there is a reasonable basis and the relevant facts of that position are disclosed on the return.

        If any item of income, gain, loss or deduction included in the distributive shares of unitholders might result in that kind of an "understatement" of income for which no "substantial authority" exists but for which a reasonable basis for the tax treatment of such item exists, we must disclose the relevant facts on our return. In such a case, we will make a reasonable effort to furnish sufficient information for unitholders to make adequate disclosure on their returns and to take other actions as may be appropriate to permit unitholders to avoid liability for this penalty. More stringent rules apply to "tax shelters," a term that in this context does not appear to include us.

        A substantial valuation misstatement exists if (a) the value of any property, or the tax basis of any property, claimed on a tax return is 150% or more of the amount determined to be the correct amount of the valuation or tax basis, (b) the price for any property or services (or for the use of property) claimed on any such return with respect to any transaction between persons described in Internal Revenue Code Section 482 is 200% or more (or 50% or less) of the amount determined under Section 482 to be the correct amount of such price, or (c) the net Internal Revenue Code Section 482 transfer price adjustment for the taxable year exceeds the lesser of $5 million or 10% of the taxpayer's gross receipts. No penalty is imposed unless the portion of the underpayment attributable to a substantial valuation misstatement exceeds $5,000 ($10,000 for a corporation other than an S Corporation or a personal holding company). The penalty is increased to 40% in the event of a gross valuation misstatement. We do not anticipate making any valuation misstatements.

        Reportable Transactions.    If we were to engage in a "reportable transaction," we (and possibly you and others) would be required to make a detailed disclosure of the transaction to the IRS. A transaction may be a reportable transaction based upon any of several factors, including the fact that it is a type of tax avoidance transaction publicly identified by the IRS as a "listed transaction" or that it

42

produces certain kinds of losses for partnerships, individuals, S corporations and trusts in excess of $2 million in any single year, or $4 million in any combination of 6 successive tax years. Our participation in a reportable transaction could increase the likelihood that our federal income tax information return (and possibly your tax return) would be audited by the IRS. Please read "—Information Returns and Audit Procedures."

        Moreover, if we were to participate in a reportable transaction with a significant purpose to avoid or evade tax, or in any listed transaction, you may be subject to the following provisions of the American Jobs Creation Act of 2004:

•

accuracy related penalties with a broader scope, significantly narrower exceptions, and potentially greater amounts than described above at "—Accuracy Related Penalties,"

•

for those persons otherwise entitled to deduct interest on federal tax deficiencies, nondeductibility of interest on any resulting tax liability and

•

in the case of a listed transaction, an extended statute of limitations.

We do not expect to engage in any "reportable transactions."

State, Local and Other Tax Considerations

        In addition to federal income taxes, you likely will be subject to other taxes, including state, local and foreign income taxes, unincorporated business taxes, and estate, inheritance or intangible taxes that may be imposed by the various jurisdictions in which we do business or own property or in which you are a resident. We currently do business or own property in ten states, most of which impose income taxes. Although an analysis of those various taxes is not presented here, each prospective unitholder is urged to consider their potential impact on his investment in us. We may also own property or do business in other jurisdictions in the future. You may not be required to file a return and pay taxes in some jurisdictions because your income from that jurisdiction falls below the filing and payment requirement. You will be required, however, to file income tax returns and to pay income taxes in many of the jurisdictions in which we do business or own property, and you may be subject to penalties for failure to comply with those requirements. In some jurisdictions, tax losses may not produce a tax benefit in the year incurred and also may not be available to offset income in subsequent taxable years. Some of the jurisdictions may require us, or we may elect, to withhold a percentage of income from amounts to be distributed to a unitholder who is not a resident of the jurisdiction. Withholding, the amount of which may be greater or less than a particular unitholder's income tax liability to the jurisdiction, generally does not relieve a non-resident unitholder from the obligation to file an income tax return. Amounts withheld may be treated as if distributed to unitholders for purposes of determining the amounts distributed by us. Please read "—Tax Consequences of Unit Ownership—Entity Level Collections." Based on current law and our estimate of our future operations, the general partner anticipates that any amounts required to be withheld will not be material.

        It is the responsibility of each unitholder to investigate the legal and tax consequences, under the laws of pertinent jurisdiction and localities, of his investment in us. Vinson & Elkins L.L.P. has not rendered an opinion on the state, local or foreign tax consequences of an investment in us. We strongly recommend that each prospective unitholder consult, and depend upon, his own tax counsel or other advisor with regard to those matters. It is the responsibility of each unitholder to file all state, local or foreign as well as United States federal tax returns, that may be required of him.

Tax Consequences of Ownership of Debt Securities

        A description of the material federal income tax consequences of the acquisition, ownership and disposition of debt securities will be set forth on the prospectus supplement relating to the offering of debt securities.

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INVESTMENT IN MARKWEST ENERGY PARTNERS BY EMPLOYEE BENEFIT PLANS

        An investment in our units or debt securities by an employee benefit plan is subject to certain additional considerations because the investments of these plans are subject to the fiduciary responsibility and prohibited transaction provisions of the Employee Retirement Income Security Act of 1974, as amended ("ERISA"), and restrictions imposed by Section 4975 of the Internal Revenue Code of 1986, as amended (the "Code"), and provisions under any federal, state, local, non-U.S. or other laws or regulations that are similar to such provisions of the Code or ERISA (collectively, "Similar Laws"). As used herein, the term "employee benefit plan" includes, but is not limited to, qualified pension, profitsharing and stock bonus plans, Keogh plans, simplified employee pension plans and tax deferred annuities or individual retirement accounts on other arrangements established or maintained by an employer or employee organization, and entities whose underlying assets are considered to include "plan assets" of such plans, accounts and arrangements.

General Fiduciary Matters

        ERISA and the Code impose certain duties on persons who are fiduciaries of an employee benefit plan that is subject to Title I of ERISA or Section 4975 of the Code (an "ERISA Plan") and prohibit certain transactions involving the assets of an ERISA Plan and its fiduciaries or other interested parties. Under ERISA and the Code, any person who exercises any discretionary authority or control over the administration of such an ERISA Plan or the management or disposition of the assets of such an ERISA Plan, or who renders investment advice for a fee or other compensation to such an ERISA plan, is generally considered to be a fiduciary of the ERISA Plan. In considering an investment in our units or debt securities, among other things, consideration should be given to:

        (a)   whether the investment is prudent under Section 404(a)(1)(B) of ERISA and any other applicable Similar Laws;

        (b)   whether in making the investment, that plan will satisfy the diversification requirements of Section 404(a)(l)(C) of ERISA and any other applicable Similar Laws;

        (c)   whether the investment will result in recognition of unrelated business taxable income by the plan and, if so, the potential after-tax investment return. See "Material Tax Consequences" beginning on page 28 of this prospectus; and

        (d)   whether making the investment will comply with the delegation of control and prohibited transaction provisions of ERISA, the Code and any other applicable Similar Laws.

        The person with investment discretion with respect to the assets of an employee benefit plan, often called a fiduciary, should determine whether an investment in our units or debt securities is authorized by the appropriate governing instrument and is a proper investment for the plan.

Prohibited Transaction Issues

        Section 406 of ERISA and Section 4975 of the Internal Revenue Code prohibit employee benefit plans, and IRAs that are not considered part of an employee benefit plan, from engaging in specified transactions involving "plan assets" with parties that are "parties in interest" under ERISA or "disqualified persons" under the Internal Revenue Code with respect to the plan, unless an exemption is available. A party in interest or disqualified person who engages in a non- exempt prohibited transaction may be subject to excise taxes and other penalties and liabilities under ERISA and the Code. In addition, the fiduciary of the ERISA Plan that engaged in such a non-exempt prohibited transaction may be subject to penalties and liabilities under ERISA and the Code.

        The acquisition and/or holding of debt securities by an ERISA Plan with respect to which we or the initial purchasers are considered a party in interest or a disqualified person, may constitute or result in a direct or indirect prohibited transaction under Section 406 of ERISA and/or Section 4975 of

44

the Code, unless the debt securities are acquired and held in accordance with an applicable statutory, class or individual prohibited transaction exemption. In this regard, the U.S. Department of Labor has issued prohibited transaction class exemptions, or PTCEs, that may apply to the acquisition, holding and, if applicable, conversion of the debt securities. These class exemptions include, without limitation, PTCE 84-14 respecting transactions determined by independent qualified professional asset managers, PTCE 90-1 respecting insurance company pooled separate accounts, PTCE 91-38 respecting bank collective investment funds, PTCE 95-60 respecting life insurance company general accounts and PTCE 96-23 respecting transactions determined by in-house asset managers. There can be no assurance that all of the conditions of any such exemptions will be satisfied.

        Because of the foregoing, our debt securities should not be purchased or held (or converted to equity securities, in the case of any convertible debt) by a person investing "plan assets" of any employee benefit plan, unless such purchase and holding (or conversion, if any) will not constitute a non-exempt prohibited transaction under ERISA or the Code or similar violation of any applicable Similar Laws.

Representation

        Accordingly, by acceptance of our debt securities, each purchaser and subsequent transferee of the debt securities will be deemed to have represented and warranted that either (i) no portion of the assets used by such purchaser or transferee to acquire and hold the notes constitutes assets of any employee benefit plan or (ii) the purchase and holding (and any conversion, if applicable) of the notes by such purchaser or transferee will not constitute a non-exempt prohibited transaction under Section 406 of ERISA or Section 4975 of the Code or similar violation under any applicable Similar Laws.

Plan Asset Issues

        In addition to considering whether the purchase of our units or debt securities is a prohibited transaction, a fiduciary of an employee benefit plan should consider whether the plan will, by investing in us, be deemed to own an undivided interest in our assets, with the result that our general partner also would be a fiduciary of the plan and our operations would be subject to the regulatory restrictions of ERISA, including its prohibited transaction rules, as well as the prohibited transaction rules of the Internal Revenue Code and any other applicable Similar Laws.

        The Department of Labor regulations provide guidance with respect to whether the assets of an entity in which employee benefit plans acquire equity interests would be deemed "plan assets" under certain circumstances. Under these regulations, an entity's assets would not be considered to be "plan assets" if, among other things,

        (a)   the equity interests acquired by employee benefit plans are publicly offered securities, i.e., the equity interests are widely held by 100 or more investors independent of the issuer and each other, freely transferable and registered pursuant to certain provisions of the federal securities laws,

        (b)   the entity is an "operating company," that is, it is primarily engaged in the production or sale of a product or service other than the investment of capital either directly or through a majority owned subsidiary or subsidiaries, or

        (c)   there is no significant investment by benefit plan investors, which is defined to mean that less than 25% of the value of each class of equity interest, disregarding certain interests held by our general partner, its affiliates, and some other persons, is held by the employee benefit plans that are subject to party of Title I of ERISA (which excludes governmental plans and non-electing church plans) and/or section 4975 of the Code.

        With respect to an investment in our units, our assets should not be considered "plan assets" under these regulations because it is expected that the investment will satisfy the requirements in

45

(a) and (b) above and may also satisfy the requirements in (c) above (although we do not monitor the level of benefit plan investors as required for compliance with (c)). With respect to an investment in our debt securities, our assets should not be considered "plan assets" under these regulations because such securities are not equity securities or, even if they are issued with a feature that allows their conversion to equity securities, the securities in which they will be convertible will satisfy the requirements in (a) and (b) above.

        The foregoing discussion of issues arising for employee benefit plan investments under ERISA, the Code and Similar Laws should not be construed as legal advice. Plan fiduciaries contemplating a purchase of common units are urged to consult with their own counsel regarding the consequences under ERISA, the Internal Revenue Code and Similiar Laws in light of the serious penalties imposed on persons who engage in prohibited transactions or other violations.

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PLAN OF DISTRIBUTION

        Under this prospectus, we intend to offer our securities to the public:

•

through one or more broker-dealers;

•

through underwriters; or

•

directly to investors.

        We will fix a price or prices of our securities at:

•

market prices prevailing at the time of any sale under this registration statement;

•

prices related to market prices; or

•

negotiated prices.

        We may change the price of the securities offered from time to time.

        We will pay or allow distributors' or sellers' commissions that will not exceed those customary in the types of transactions involved. Broker-dealers may act as agent or may purchase securities as principal and thereafter resell the securities from time to time:

•

in or through one or more transactions (which may involve crosses and block transactions) or distributions;

•

on the New York Stock Exchange;

•

in the over-the-counter market; or

•

in private transactions.

        Broker-dealers or underwriters may receive compensation in the form of underwriting discounts or commissions and may receive commissions from purchasers of the securities for whom they may act as agents. If any broker-dealer purchases the securities as principal, it may effect resales of the securities from time to time to or through other broker-dealers, and other broker-dealers may receive compensation in the form of concessions or commissions from the purchasers of securities for whom they may act as agents.

        To the extent required, the names of the specific managing underwriter or underwriters, if any, as well as other important information, will be set forth in prospectus supplements. In that event, the discounts and commissions we will allow or pay to the underwriters, if any, and the discounts and commissions the underwriters may allow or pay to dealers or agents, if any, will be set forth in, or may be calculated from, the prospectus supplements. Any underwriters, brokers, dealers and agents who participate in any sale of the securities may also engage in transactions with, or perform services for, us or our affiliates in the ordinary course of their businesses. We may indemnify underwriters, brokers, dealers and agents against specific liabilities, including liabilities under the Securities Act.

        Offers to purchase securities may be solicited directly by us and the sale thereof may be made by us directly to institutional investors or others, who may be deemed to be underwriters within the meaning of the Securities Act of 1933 with respect to any resale thereof. The terms of any such sales will be described in the prospectus supplement relating thereto.

        We may offer our units into an existing trading market on the terms described in the prospectus supplement relating thereto. Underwriters and dealers who may participate in any at-the-market offerings will be described in the prospectus supplement relating thereto.

        The aggregate maximum compensation the underwriters will receive in connection with the sale of any securities under this prospectus and the registration statement of which it forms a part will not exceed 10% of the gross proceeds from the sale.

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        Because FINRA views our common units as interests in a direct participation program, any offering of common units under the registration statement of which this prospectus forms a part will be made in compliance with Rule 2310 of the FINRA Rules.

        To the extent required, this prospectus may be amended or supplemented from time to time to describe a specific plan of distribution. The place and time of delivery for the securities in respect of which this prospectus is delivered will be set forth in the accompanying prospectus supplement.

        In connection with offerings under this shelf registration and in compliance with applicable law, underwriters, brokers or dealers may engage in transactions which stabilize or maintain the market price of the securities at levels above those which might otherwise prevail in the open market. Specifically, underwriters, brokers or dealers may over-allot in connection with offerings, creating a short position in the securities for their own accounts. For the purpose of covering a syndicate short position or stabilizing the price of the securities, the underwriters, brokers or dealers may place bids for the securities or effect purchases of the securities in the open market. Finally, the underwriters may impose a penalty whereby selling concessions allowed to syndicate members or other brokers or dealers for distribution the securities in offerings may be reclaimed by the syndicate if the syndicate repurchases previously distributed securities in transactions to cover short positions, in stabilization transactions or otherwise. These activities may stabilize, maintain or otherwise affect the market price of the securities, which may be higher than the price that might otherwise prevail in the open market, and, if commenced, may be discontinued at any time.

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LEGAL MATTERS

        In connection with particular offerings of the securities in the future, and if stated in the applicable prospectus supplement, the validity of those securities may be passed upon for us by Vinson & Elkins L.L.P. and for any underwriters or agents by counsel named in the applicable prospectus supplement.

EXPERTS

        The consolidated financial statements incorporated in this registration statement by reference from our annual report on Form 10-K for the year ended December 31, 2008, as modified by our current report on Form 8-K filed on May 18, 2009 for the retrospective applications of changes to generally accepted accounting principles related to the presentation of non-controlling interest and the calculation of earnings per unit, have been audited by Deloitte & Touche LLP, an independent registered public accounting firm, as stated in their reports, which are incorporated herein by reference. MarkWest Energy Partners, L.P.'s internal control over financial reporting as of December 31, 2008 has been audited by Deloitte & Touche LLP, as stated in their report in our annual report on Form 10-K for the year ended December 31, 2008, which is incorporated herein by reference. Such financial statements have been so incorporated in reliance upon the reports of such firm given upon their authority as experts in accounting and auditing.

        The financial statements of Starfish Pipeline Company, LLC as of December 31, 2007 and for each of the two years in the period ended December 31, 2007 incorporated in this registration statement by reference to MarkWest Energy Partners, L.P.'s annual report on Form 10-K for the year ended December 31, 2008 have been so incorporated in reliance on the report (which contains an explanatory paragraph relating to significant transactions and relationships with affiliated entities as described in Note 3 to the financial statements) of PricewaterhouseCoopers LLP, independent accountants, given on the authority of said firm as experts in accounting and auditing.

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PART II

INFORMATION NOT REQUIRED IN PROSPECTUS

Item 14.    Other Expenses of Issuance and Distribution

        Set forth below are the expenses (other than underwriting discounts and commissions) expected to be incurred in connection with the issuance and distribution of the securities registered hereby. With the exception of the Securities and Exchange Commission registration fee, the amounts set forth below are estimates.

Securities and Exchange Commission registration fee		$	*
Legal fees and expenses			50,000
Accounting fees and expenses			50,000
Printing expenses			15,000
Listing fees			15,000
	TOTAL	$	130,000

*

The registrants are deferring payment of the registration fee in reliance on Rules 456(b) and 457(r).

Item 15.    Indemnification of Directors and Officers

        Section 17-108 of the Delaware Revised Limited Partnership Act empowers a Delaware limited partnership to indemnify and hold harmless any partner or other person from and against all claims and demands whatsoever. The partnership agreement of MarkWest Energy Partners, L.P. provides that, in most circumstances, we will indemnify the following persons, to the fullest extent permitted by law, from and against all losses, claims, damages or similar events:

•

our general partner;

•

any departing general partner;

•

any person who is or was an affiliate of a general partner or any departing general partner;

•

any person who is or was a member, partner, officer, director employee, agent or trustee of our general partner or any departing general partner or any affiliate of a general partner or any departing general partner; or

•

any person who is or was serving at the request of a general partner or any departing general partner or any affiliate of a general partner or any departing general partner as an officer, director, employee, member, partner, agent or trustee of another person.

        Any indemnification under these provisions will only be out of our assets. Our general partner will not be personally liable for, or have any obligation to contribute or loan funds or assets to us to enable us to effectuate, indemnification. We may purchase insurance against liabilities asserted against and expenses incurred by persons for our activities, regardless of whether we would have the power to indemnify the person against liabilities under the partnership agreement.

        Section 145 of the Delaware General Corporation Law, inter alia, empowers a Delaware corporation to indemnify any person who was or is a party or is threatened to be made a party to any threatened, pending or completed action, suit or proceeding (other than an action by or in the right of the corporation) by reason of the fact that such person is or was a director, officer, employee or agent of another corporation or other enterprise, against expenses (including attorneys' fees), judgments, fines and amounts paid in settlement actually and reasonably incurred by him in connection with such action, suit or proceeding if he acted in good faith and in a manner he reasonably believed to be in or not opposed to the best interests of the corporation, and, with respect to any criminal action or proceeding,

II-1

had no reasonable cause to believe his conduct was unlawful. Similar indemnity is authorized for such persons against expenses (including attorneys' fees) actually and reasonably incurred in connection with the defense or settlement of any such threatened, pending or completed action or suit if such person acted in good faith and in a manner he reasonably believed to be in or not opposed to the best interests of the corporation, and provided further that (unless a court of competent jurisdiction otherwise provides) such person shall not have been adjudged liable to the corporation. Any such indemnification may be made only as authorized in each specific case upon a determination by the stockholders or disinterested directors or by independent legal counsel in a written opinion that indemnification is proper because the indemnitee has met the applicable standard of conduct.

        Section 145 further authorizes a corporation to purchase and maintain insurance on behalf of any person who is or was a director, officer, employee or agent of the corporation, or is or was serving at the request of the corporation as a director, officer, employee or agent of another corporation or enterprise, against any liability asserted against him and incurred by him in any such capacity, or arising out of his status as such, whether or not the corporation would otherwise have the power to indemnify him under Section 145. Also, Article VI of the bylaws of MarkWest Energy Finance Corporation provides for the indemnification of directors and officers of the company and such directors and officers who serve at the request of the company as directors, officers, employees or agents of any other enterprise against certain liabilities under certain circumstances.

        The limited liability company agreement of MarkWest Energy GP, L.L.C. provides that it will, to the fullest extent permitted by law, indemnify and advance expenses to indemnitees (as defined therein) from and against any and all losses, claims, damages, liabilities (joint or several), expenses (including legal fees and expenses), judgments, fines, settlements and other amounts arising from any and all claims, demands, actions, suits or proceedings, civil, criminal, administrative or investigative, in which any indemnitee may be involved, or is threatened to be involved, as a party or otherwise, by reason of its status as an indemnitee, provided that in each case the indemnitee acted in good faith and in a manner which such indemnitee reasonably believed to be in, or not opposed to the best interests of, the operating company. This indemnification would under certain circumstances include indemnification for liabilities under the Securities Act. In addition, each indemnitee would automatically be entitled to the advancement of expenses in connection with the foregoing indemnification. Any indemnification under these provisions will be only out of the assets of the operating company.

        In April 2008, the Partnership and our General Partner entered into second amended and restated indemnification agreements with all of the directors and officers of the General Partner. The second amended and restated indemnification agreements become operative if the indemnitees were or are or become, or are threatened to be made, a party to or witness or other participant in, or were or are or become obligated to furnish documents in response to a subpoena or otherwise in connection with, any threatened, pending or completed claim, action, suit, proceeding, arbitration or alternative dispute resolution mechanism, investigation, inquiry, administrative hearing, appeal or any other actual, threatened or completed proceeding, whether brought in the right of the Partnership, the General Partner, their affiliates or otherwise and whether of a civil, criminal, administrative, arbitrative or investigative nature, by reason of the fact that indemnitees were or are or may be deemed a director, officer, employee, controlling person, agent or fiduciary of the Partnership, the General Partner, their affiliates or any other person for which indemnitees are or were or may be deemed to be serving at the request of the General Partner, or by reason of any action or inaction on the part of indemnitees while serving or acting or having served or acted in any that capacity. Upon the occurrence of an indemnification event, the Partnership and the General Partner will indemnify the indemnitees against all losses and expenses (as defined in the second amended and restated indemnification agreements), so long as the indemnitees acted in good faith and in a manner the indemnitees reasonably believed to be in, or not opposed to, the best interests of the General Partner, and, with respect to any criminal proceeding, had no reasonable cause to believe indemnitees' conduct was unlawful. There are certain limitations on

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the obligation of the General Partner and the Partnership to indemnify the indemnitees in connection with a claim brought by or in the name of the General Partner to obtain a judgment in its favor.

Item 16.    Exhibits(a)

        Exhibits:

Exhibit Number				Description
	1.1	*	—	Form of Underwriting Agreement
	2.1	(3)	—	Agreement and Plan of Redemption and Merger dated September 5, 2007 by and among MarkWest Hydrocarbon, Inc. MarkWest Energy Partners, L.P. and MWEP, L.L.C.
	4.1	(1)	—	Purchase Agreement dated October 19, 2004, among MarkWest Energy Partners, L.P., MarkWest Energy Finance Corporation, the Guarantors named therein and the Initial Purchasers named therein.
	4.2	(1)	—	Indenture dated as of October 25, 2004, among MarkWest Energy Partners, L.P., MarkWest Energy Finance Corporation, the Guarantors named therein and Wells Fargo Bank, National Association, as Trustee.
	4.3	(1)	—	Form of 6.875% Series A Senior Notes due 2014 with attached notation of Guarantees.
	4.4	(5)	—	First Supplemental Indenture, dated as of February 2, 2005, among MarkWest Energy Partners, L.P., MarkWest Energy Finance Corporation, the Guarantors named therein and Wells Fargo Bank, National Association, as Trustee.
	4.5	(6)	—	Second Supplemental Indenture, dated as of January 17, 2006, among MarkWest Energy Partners, L.P., MarkWest Energy Finance Corporation, the Guarantors named therein and Wells Fargo Bank, National Association, as Trustee.
	4.6	(2)	—	Indenture dated as of July 6, 2006, among MarkWest Energy Partners, L.P., MarkWest Energy Finance Corporation, as Issuers, the Guarantors named therein, and Wells Fargo Bank, National Association, as Trustee.
	4.7	(2)	—	Form of 8.5% Series A and Series B Senior Notes due 2016 with attached notation of Guarantees (incorporated by Reference to Exhibits A and D of Exhibit 4.8 hereto).
	4.8	(7)	—	Third Supplemental Indenture, dated as of March 6, 2008, among MarkWest Energy Partners, L.P., MarkWest Energy Finance Corporation, the Guarantors named therein, and Wells Fargo Bank, National Association, as Trustee.
	4.9	(7)	—	First Supplemental Indenture, dated as of March 6, 2008, among MarkWest Energy Partners, L.P., MarkWest Energy Finance Corporation, the Guarantors named therein, and Wells Fargo Bank, National Association, as Trustee.
	4.10	(4)	—	Form of 83/4% Series A and Series B Senior Notes due 2018 with attached notation of Guarantees (incorporated by reference to Exhibits A and D of Exhibit 4.14 hereto).
	4.11	(4)	—	Indenture dated as of April 15, 2008 among MarkWest Energy Partners, L.P., MarkWest Energy Finance Corporation, and the several guarantors named therein, and Wells Fargo Bank, N.A., as trustee.
	4.12	(7)	—	Fourth Supplemental Indenture, dated as of April 25, 2008, among MarkWest Energy Partners, L.P., MarkWest Energy Finance Corporation, the Guarantors named therein, and Wells Fargo Bank, National Association, as Trustee.
	4.13	(7)	—	Second Supplemental Indenture, dated as of April 25, 2008, among MarkWest Energy Partners, L.P., MarkWest Energy Finance Corporation, the Guarantors named therein, and Wells Fargo Bank, National Association, as Trustee.

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Exhibit Number				Description
	4.14	(7)	—	First Supplemental Indenture, dated as of April 25, 2008, among MarkWest Energy Partners, L.P., MarkWest Energy Finance Corporation, the Guarantors named therein, and Wells Fargo Bank, National Association, as Trustee.
	4.15	(7)	—	Fifth Supplemental Indenture, dated as of August 4, 2008, among MarkWest Energy Partners, L.P., MarkWest Energy Finance Corporation, the Guarantors named therein, and Wells Fargo Bank, National Association, as Trustee.
	4.16	(7)	—	Third Supplemental Indenture, dated as of August 4, 2008, among MarkWest Energy Partners, L.P., MarkWest Energy Finance Corporation, the Guarantors named therein, and Wells Fargo Bank, National Association, as Trustee.
	4.17	(7)	—	Second Supplemental Indenture, dated as of August 4, 2008, among MarkWest Energy Partners, L.P., MarkWest Energy Finance Corporation, the Guarantors named therein, and Wells Fargo Bank, National Association, as Trustee.
	4.18	(7)	—	Sixth Supplemental Indenture, dated as of September 15, 2008, among MarkWest Energy Partners, L.P., MarkWest Energy Finance Corporation, the Guarantors named therein, and Wells Fargo Bank, National Association, as Trustee.
	4.19	(7)	—	Fourth Supplemental Indenture, dated as of September 15, 2008, among MarkWest Energy Partners, L.P., MarkWest Energy Finance Corporation, the Guarantors named therein, and Wells Fargo Bank, National Association, as Trustee.
	4.20	(7)	—	Third Supplemental Indenture, dated as of September 15, 2008, among MarkWest Energy Partners, L.P., MarkWest Energy Finance Corporation, the Guarantors named therein, and Wells Fargo Bank, National Association, as Trustee.
	4.21	(8)	—	Indenture dated as of May 26, 2009 among MarkWest Energy Partners, L.P., MarkWest Energy Finance Corporation, and the several guarantors named therein, and Wells Fargo Bank, N.A., as Trustee.
	4.22	(9)	—	Indenture Release of Subsidiary Guarantor dated as of May 1, 2009 among MarkWest Energy Partners, L.P. and Wells Fargo Bank, N.A.
	4.23	**	—	Indenture Release of Subsidiary Guarantor dated as of October 31, 2009 among MarkWest Energy Partners, L.P. and Wells Fargo Bank, N.A.
	4.24	**	—	Form of Senior Indenture of MarkWest Energy Partners, L.P.
	4.25	**	—	Form of Subordinated Indenture of MarkWest Energy Partners, L.P
	5.1	**	—	Opinion of Vinson & Elkins L.L.P.
	8.1	**	—	Opinion of Vinson & Elkins L.L.P. relating to tax matters
	12.1	**	—	Computation of Ratio of Earnings to Fixed Charges.
	21.1	**	—	List of Subsidiaries.
	23.1	**	—	Consent of Deloitte & Touche LLP.
	23.2	**	—	Consent of PricewaterhouseCoopers LLP
	24.1	**	—	Power of Attorney (included on signature page of this registration statement)
	25.1	**	—	Form T-1 Statement of Eligibility and Qualification under the Trust Indenture Act of 1939 of the Trustee under the Senior Indenture

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Exhibit Number				Description
	25.2	**	—	Form T-1 Statement of Eligibility and Qualification under the Trust Indenture Act of 1939 of the Trustee under the Subordinated Indenture

(1)

Incorporated by reference to the Current Report on Form 8-K filed October 25, 2004.

(2)

Incorporated by reference to the Current Report on Form 8-K filed July 7, 2006.

(3)

Incorporated by reference to the Current Report on Form 8-K filed September 6, 2007.

(4)

Incorporated by reference to the Current Report on Form 8-K filed April 15, 2008.

(5)

Incorporated by reference to the Form S-4 Registration Statement filed February 22, 2005.

(6)

Incorporated by reference to the Form S-4/A Registration Statement filed January 17, 2006.

(7)

Incorporated by reference to the Annual Report on Form 10-K filed March 2, 2009.

(8)

Incorporated by reference to the Current Report on Form 8-K filed May 27, 2009.

(9)

Incorporated by reference to the Quarterly Report on Form 10-Q filed on August 10, 2009.

*

To be filed

**

Filed herewith.

Item 17.    Undertakings.

        The undersigned registrant hereby undertakes:

        (1)   To file, during any period in which offers or sales are being made, a post-effective amendment to this registration statement:

(i)

To include any prospectus required by section 10(a)(3) of the Securities Act of 1933;



(ii)

To reflect in the prospectus any facts or events arising after the effective date of the registration statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in the registration statement. Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with the Commission pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than 20% change in the maximum aggregate offering price set forth in the "Calculation of Registration Fee" table in the effective registration statement;



(iii)

To include any material information with respect to the plan of distribution not previously disclosed in the registration statement or any material change to such information in the registration statement;

provided, however, that paragraphs (1)(i) and (1)(ii) do not apply if information required to be included in a post-effective amendment by those paragraphs is contained in periodic reports filed by registrants pursuant to Section 13 or Section 15(d) of the Securities Exchange Act of 1934 that are incorporated by reference in the registration statement, or is contained in a form of prospectus filed pursuant to Rule 424(b) that is part of the registration statement.

        (2)   That, for the purpose of determining any liability under the Securities Act of 1933, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

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        (3)   To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.

        (4)   That, for the purpose of determining liability under the Securities Act of 1933 to any purchaser:

(i)

If the registrant is relying on Rule 430B:

        A.    Each prospectus filed by the registrant pursuant to Rule 424(b)(3) shall be deemed to be part of the registration statement as of the date the filed prospectus was deemed part of and included in the registration statement; and

        B.    Each prospectus required to be filed pursuant to Rule 424(b)(2), (b)(5), or (b)(7) as part of a registration statement in reliance on Rule 430B relating to an offering made pursuant to Rule 415(a)(1)(i), (vii), or (x) for the purpose of providing the information required by section 10(a) of the Securities Act of 1933 shall be deemed to be part of and included in the registration statement as of the earlier of the date such form of prospectus is first used after effectiveness or the date of the first contract of sale of securities in the offering described in the prospectus. As provided in Rule 430B, for liability purposes of the issuer and any person that is at that date an underwriter, such date shall be deemed to be a new effective date of the registration statement relating to the securities in the registration statement to which that prospectus relates, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof. Provided, however, that no statement made in a registration statement or prospectus that is part of the registration statement or made in a document incorporated or deemed incorporated by reference into the registration statement or prospectus that is part of the registration statement will, as to a purchaser with a time of contract of sale prior to such effective date, supersede or modify any statement that was made in the registration statement or prospectus that was part of the registration statement or made in any such document immediately prior to such effective date; or

(ii)

If the registrant is subject to Rule 430C, each prospectus filed pursuant to Rule 424(b) as part of a registration statement relating to an offering, other than registration statements relying on Rule 430B or other than prospectuses filed in reliance on Rule 430A, shall be deemed to be part of and included in the registration statement as of the date it is first used after effectiveness. Provided, however, that no statement made in a registration statement or prospectus that is part of the registration statement or made in a document incorporated or deemed incorporated by reference into the registration statement or prospectus that is part of the registration statement will, as to a purchaser with a time of contract of sale prior to such first use, supersede or modify any statement that was made in the registration statement or prospectus that was part of the registration statement or made in any such document immediately prior to such date of first use.

        (5)   That, for the purpose of determining liability of the registrant under the Securities Act of 1933 to any purchaser in the initial distribution of the securities, the registrant undertakes that in a primary offering of securities of the registrant pursuant to this registration statement, regardless of the underwriting method used to sell the securities to the purchaser, if the securities are offered or sold to such purchaser by means of any of the following communications, the registrant will be a seller to the purchaser and will be considered to offer or sell such securities to such purchaser:

(i)

Any preliminary prospectus or prospectus of the registrant relating to the offering required to be filed pursuant to Rule 424;



(ii)

Any free writing prospectus relating to the offering prepared by or on behalf of an undersigned registrant or used or referred to by the registrant;

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(iii)

The portion of any other free writing prospectus relating to the offering containing material information about the registrant or its securities provided by or on behalf of the registrant; and



(iv)

Any other communication that is an offer in the offering made by the registrant to the purchaser.

        (6)   That, for purposes of determining any liability under the Securities Act of 1933, each filing of the registrant's annual report pursuant to Section 13(a) or 15(d) of the Securities Exchange Act of 1934 (and, where applicable, each filing of an employee benefit plan's annual report pursuant to Section 15(d) of the Securities Exchange Act of 1934) that is incorporated by reference in the registration statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

        (7)   Insofar as indemnification for liabilities arising under the Securities Act of 1933 may be permitted to directors, officers and controlling persons of each registrant pursuant to the foregoing provisions, or otherwise, the registrant has been advised that in the opinion of the SEC such indemnification is against public policy as expressed in the Securities Act of 1933 and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the registrant of expenses incurred or paid by a director, officer or controlling person of the registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act of 1933 and will be governed by the final adjudication of such issue.

        (8)   The undersigned registrant hereby undertakes to file an application for the purpose of determining the eligibility of the trustee to act under subsection (a) of Section 310 of the Trust Indenture Act ("Act") in accordance with the rules and regulations prescribed by the Commission under Section 305(b)2 of the Act.

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SIGNATURES

        Pursuant to the requirements of the Securities Act of 1933, as amended, the Registrant has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Denver, state of Colorado, on January 13, 2010.

MARKWEST ENERGY PARTNERS, L.P. (Registrant)
By:	MARKWEST ENERGY GP, L.L.C., Its General Partner
By:	/s/ NANCY K. BUESE Nancy K. Buese Senior Vice President and Chief Financial Officer

        KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below constitutes and appoints Nancy K. Buese and Frank M. Semple, and each of them, his true and lawful attorneys-in-fact and agents, with full power of substitution, for him and in his name, place and stead, in any and all capacities, to sign any and all amendments (including post-effective amendments) to this registration statement and any additional registration statement pursuant to Rule 462(b), and to file the same with all exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents full power and authority to do and perform each and every act and thing requisite and necessary to be done in connection therewith, as fully and to all intents and purposes as they might or could not in person, hereby ratifying and confirming all that said attorneys-in-fact and agents or any of them, or their or his or her substitute or substitutes may lawfully do or cause to be done by virtue hereof.

        Pursuant to the requirements of the Securities Act of 1933, as amended, this Registration Statement has been signed below by the following persons in the capacities and on the dates indicated.

Signature	Title
Date: January 13, 2010	By:	/s/ FRANK M. SEMPLE Frank M. Semple President, Chief Executive Officer, Chairman of the Board and Director (Principal Executive Officer)
Date: January 13, 2010	By:	/s/ NANCY K. BUESE Nancy K. Buese Senior Vice President and Chief Financial Officer (Principal Financial and Accounting Officer)

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Signature	Title
Date: January 13, 2010	By:	/s/ JOHN M. FOX John M. Fox Lead Director
Date: January 13, 2010	By:	/s/ KEITH E. BAILEY Keith E. Bailey Director
Date: January 13, 2010	By:	/s/ MICHAEL L. BEATTY Michael L. Beatty Director
Date: January 13, 2010	By:	/s/ CHARLES K. DEMPSTER Charles K. Dempster Director
Date: January 13, 2010	By:	/s/ DONALD C. HEPPERMAN Donald C. Hepperman Director
Date: January 13, 2010	By:	/s/ WILLIAM A. KELLSTROM William A. Kellstrom Director
Date: January 13, 2010	By:	/s/ ANNE E. FOX MOUNSEY Anne E. Fox Mounsey Director
Date: January 13, 2010	By:	/s/ WILLIAM P. NICOLETTI William P. Nicoletti Director

II-9

SIGNATURES

        Pursuant to the requirements of the Securities Act of 1933, as amended, the registrant has duly caused this Registration Statement on Form S-3 to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Denver, State of Colorado, on the 13th day of January, 2010.

MARKWEST ENERGY FINANCE CORPORATION
By:	/s/ NANCY K. BUESE Nancy K. Buese Senior Vice President and Chief Financial Officer

        KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below constitutes and appoints Nancy K. Buese and Frank M. Semple, and each of them, his true and lawful attorneys-in-fact and agents, with full power of substitution, for him and in his name, place and stead, in any and all capacities, to sign any and all amendments (including post-effective amendments) to this registration statement and any additional registration statement pursuant to Rule 462(b), and to file the same with all exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents full power and authority to do and perform each and every act and thing requisite and necessary to be done in connection therewith, as fully and to all intents and purposes as they might or could not in person, hereby ratifying and confirming all that said attorneys-in-fact and agents or any of them, or their or his or her substitute or substitutes may lawfully do or cause to be done by virtue hereof.

        Pursuant to the requirements of the Securities Act of 1933, as amended, this Registration Statement on Form S-3 has been signed below by the following persons in the capacities indicated on the 13th day of January, 2010.

Signature	Title
/s/ FRANK M. SEMPLE Frank M. Semple	Chief Executive Officer, President and Director of MarkWest Energy Finance Corporation (Principal Executive Officer)
/s/ NANCY K. BUESE Nancy K. Buese	Senior Vice President, Chief Financial Officer and Director of MarkWest Energy Finance Corporation (Principal Financial and Accounting Officer)

II-10

SIGNATURES

        Pursuant to the requirements of the Securities Act of 1933, as amended, the registrant has duly caused this Registration Statement on Form S-3 to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Denver, State of Colorado, on the 13th day of January, 2010.

MARKWEST ENERGY OPERATING COMPANY, L.L.C.
By:	MARKWEST ENERGY PARTNERS, L.P., its Managing Member
By:	MARKWEST ENERGY GP, L.L.C., its General Partner
By:	/s/ NANCY K. BUESE Nancy K. Buese Senior Vice President and Chief Financial Officer

        KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below constitutes and appoints Nancy K. Buese and Frank M. Semple, and each of them, his true and lawful attorneys-in-fact and agents, with full power of substitution, for him and in his name, place and stead, in any and all capacities, to sign any and all amendments (including post-effective amendments) to this registration statement and any additional registration statement pursuant to Rule 462(b), and to file the same with all exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents full power and authority to do and perform each and every act and thing requisite and necessary to be done in connection therewith, as fully and to all intents and purposes as they might or could not in person, hereby ratifying and confirming all that said attorneys-in-fact and agents or any of them, or their or his or her substitute or substitutes may lawfully do or cause to be done by virtue hereof.

        Pursuant to the requirements of the Securities Act of 1933, as amended, this Registration Statement on Form S-3 has been signed below by the following persons in the capacities indicated on the 13th day of January, 2010.

Signature	Title
/s/ FRANK M. SEMPLE Frank M. Semple	President, Chief Executive Officer, Chairman of the Board and Director of MarkWest Energy GP, L.L.C., General Partner of MarkWest Energy Partners, L.P. (Principal Executive Officer)
/s/ NANCY K. BUESE Nancy K. Buese	Senior Vice President and Chief Financial Officer of MarkWest Energy GP, L.L.C., General Partner of MarkWest Energy Partners, L.P. (Principal Financial and Accounting Officer)
/s/ JOHN M. FOX John M. Fox	Lead Director of MarkWest Energy GP, L.L.C., General Partner of MarkWest Energy Partners, L.P.

II-11

Signature	Title
/s/ KEITH E. BAILEY Keith E. Bailey	Director of MarkWest Energy GP, L.L.C., General Partner of MarkWest Energy Partners, L.P.
/s/ MICHAEL L. BEATTY Michael L. Beatty	Director of MarkWest Energy GP, L.L.C., General Partner of MarkWest Energy Partners, L.P.
/s/ CHARLES K. DEMPSTER Charles K. Dempster	Director of MarkWest Energy GP, L.L.C., General Partner of MarkWest Energy Partners, L.P.
/s/ DONALD C. HEPPERMAN Donald C. Hepperman	Director of MarkWest Energy GP, L.L.C., General Partner of MarkWest Energy Partners, L.P.
/s/ WILLIAM A. KELLSTROM William A. Kellstrom	Director of MarkWest Energy GP, L.L.C., General Partner of MarkWest Energy Partners, L.P.
/s/ ANNE E. FOX MOUNSEY Anne E. Fox Mounsey	Director of MarkWest Energy GP, L.L.C., General Partner of MarkWest Energy Partners, L.P.
/s/ WILLIAM P. NICOLETTI William P. Nicoletti	Director of MarkWest Energy GP, L.L.C., General Partner of MarkWest Energy Partners, L.P.

II-12

SIGNATURES

        Pursuant to the requirements of the Securities Act of 1933, as amended, each registrant has duly caused this Registration Statement on Form S-3 to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Denver, State of Colorado, on the 13th day of January, 2010.

WEST SHORE PROCESSING COMPANY, L.L.C. MARKWEST ENERGY APPALACHIA, L.L.C. MARKWEST MICHIGAN PIPELINE COMPANY, L.L.C. MARKWEST OKLAHOMA GAS COMPANY, L.L.C. MARKWEST POWER TEX, L.L.C. MARKWEST PINNACLE, L.L.C. MARKWEST PNG UTILITY, L.L.C. MARKWEST TEXAS PNG UTILITY, L.L.C. MARKWEST BLACKHAWK, L.L.C. MARKWEST NEW MEXICO, L.L.C. MARKWEST ENERGY EAST TEXAS GAS COMPANY, L.L.C. MARKWEST PIPELINE COMPANY, L.L.C. MARKWEST JAVELINA PIPELINE COMPANY, L.L.C. MARKWEST JAVELINA COMPANY, L.L.C. MARKWEST GAS SERVICES, L.L.C. MARKWEST LIBERTY GAS GATHERING, L.L.C. MARKWEST MARKETING, L.L.C. MARKWEST GAS MARKETING, L.L.C.
By:	MARKWEST ENERGY OPERATING COMPANY, L.L.C., their Sole Member
By:	MARKWEST ENERGY PARTNERS, L.P., its Managing Member
By:	MARKWEST ENERGY GP, L.L.C., its General Partner
By:	/s/ NANCY K. BUESE Nancy K. Buese Senior Vice President and Chief Financial Officer

        KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below constitutes and appoints Nancy K. Buese and Frank M. Semple, and each of them, his true and lawful attorneys-in-fact and agents, with full power of substitution, for him and in his name, place and stead, in any and all capacities, to sign any and all amendments (including post-effective amendments) to this registration statement and any additional registration statement pursuant to Rule 462(b), and to file the same with all exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents full power and authority to do and perform each and every act and thing requisite and necessary to be done in connection therewith, as fully and to all intents and purposes as they might or could not in person, hereby ratifying and confirming all that said attorneys-in-fact and agents or any of them, or their or his or her substitute or substitutes may lawfully do or cause to be done by virtue hereof.

II-13

        Pursuant to the requirements of the Securities Act of 1933, as amended, this Registration Statement on Form S-3 has been signed below by the following persons in the capacities indicated on the 13th day of January, 2010.

Signature	Title
/s/ FRANK M. SEMPLE Frank M. Semple	President, Chief Executive Officer, Chairman of the Board and Director of MarkWest Energy GP, L.L.C., General Partner of MarkWest Energy Partners, L.P. (Principal Executive Officer)
/s/ NANCY K. BUESE Nancy K. Buese	Senior Vice President and Chief Financial Officer of MarkWest Energy GP, L.L.C., General Partner of MarkWest Energy Partners, L.P. (Principal Financial and Accounting Officer)
/s/ JOHN M. FOX John M. Fox	Lead Director of MarkWest Energy GP, L.L.C., General Partner of MarkWest Energy Partners, L.P.
/s/ KEITH E. BAILEY Keith E. Bailey	Director of MarkWest Energy GP, L.L.C., General Partner of MarkWest Energy Partners, L.P.
/s/ MICHAEL L. BEATTY Michael L. Beatty	Director of MarkWest Energy GP, L.L.C., General Partner of MarkWest Energy Partners, L.P.
/s/ CHARLES K. DEMPSTER Charles K. Dempster	Director of MarkWest Energy GP, L.L.C., General Partner of MarkWest Energy Partners, L.P.
/s/ DONALD C. HEPPERMAN Donald C. Hepperman	Director of MarkWest Energy GP, L.L.C., General Partner of MarkWest Energy Partners, L.P.
/s/ WILLIAM A. KELLSTROM William A. Kellstrom	Director of MarkWest Energy GP, L.L.C., General Partner of MarkWest Energy Partners, L.P.
/s/ ANNE E. FOX MOUNSEY Anne E. Fox Mounsey	Director of MarkWest Energy GP, L.L.C., General Partner of MarkWest Energy Partners, L.P.
/s/ WILLIAM P. NICOLETTI William P. Nicoletti	Director of MarkWest Energy GP, L.L.C., General Partner of MarkWest Energy Partners, L.P.

II-14

SIGNATURES

        Pursuant to the requirements of the Securities Act of 1933, as amended, each registrant has duly caused this Registration Statement on Form S-3 to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Denver, State of Colorado, on the 13th day of January, 2010.

MARKWEST ENERGY GP, L.L.C.
By:	/s/ NANCY K. BUESE Nancy K. Buese Senior Vice President and Chief Financial Officer

        KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below constitutes and appoints Nancy K. Buese and Frank M. Semple, and each of them, his true and lawful attorneys-in-fact and agents, with full power of substitution, for him and in his name, place and stead, in any and all capacities, to sign any and all amendments (including post-effective amendments) to this registration statement and any additional registration statement pursuant to Rule 462(b), and to file the same with all exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents full power and authority to do and perform each and every act and thing requisite and necessary to be done in connection therewith, as fully and to all intents and purposes as they might or could not in person, hereby ratifying and confirming all that said attorneys-in-fact and agents or any of them, or their or his or her substitute or substitutes may lawfully do or cause to be done by virtue hereof.

        Pursuant to the requirements of the Securities Act of 1933, as amended, this Registration Statement on Form S-3 has been signed below by the following persons in the capacities indicated on the 13th day of January, 2010.

Signature	Title
/s/ FRANK M. SEMPLE Frank M. Semple	President, Chief Executive Officer, Chairman of the Board and Director (Principal Executive Officer)
/s/ NANCY K. BUESE Nancy K. Buese	Senior Vice President and Chief Financial Officer (Principal Financial and Accounting Officer)
/s/ JOHN M. FOX John M. Fox	Lead Director
/s/ KEITH E. BAILEY Keith E. Bailey	Director

II-15

Signature	Title
/s/ MICHAEL L. BEATTY Michael L. Beatty	Director
/s/ CHARLES K. DEMPSTER Charles K. Dempster	Director
/s/ DONALD C. HEPPERMAN Donald C. Hepperman	Director
/s/ WILLIAM A. KELLSTROM William A. Kellstrom	Director
/s/ ANNE E. FOX MOUNSEY Anne E. Fox Mounsey	Director
/s/ WILLIAM P. NICOLETTI William P. Nicoletti	Director

II-16

SIGNATURES

        Pursuant to the requirements of the Securities Act of 1933, as amended, each registrant has duly caused this Registration Statement on Form S-3 to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Denver, State of Colorado, on the 13th day of January, 2010.

MARKWEST MCALESTER, L.L.C.
By:	MARKWEST OKLAHOMA GAS COMPANY, L.L.C., its Sole Member
By:	MARKWEST ENERGY OPERATING COMPANY, L.L.C., its Sole Member
By:	MARKWEST ENERGY PARTNERS, L.P., its Managing Member
By:	MARKWEST ENERGY GP, L.L.C., its General Partner
By:	/s/ NANCY K. BUESE Nancy K. Buese Senior Vice President and Chief Financial Officer

        KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below constitutes and appoints Nancy K. Buese and Frank M. Semple, and each of them, his true and lawful attorneys-in-fact and agents, with full power of substitution, for him and in his name, place and stead, in any and all capacities, to sign any and all amendments (including post-effective amendments) to this registration statement and any additional registration statement pursuant to Rule 462(b), and to file the same with all exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents full power and authority to do and perform each and every act and thing requisite and necessary to be done in connection therewith, as fully and to all intents and purposes as they might or could not in person, hereby ratifying and confirming all that said attorneys-in-fact and agents or any of them, or their or his or her substitute or substitutes may lawfully do or cause to be done by virtue hereof.

II-17

        Pursuant to the requirements of the Securities Act of 1933, as amended, this Registration Statement on Form S-3 has been signed below by the following persons in the capacities indicated on the 13th day of January, 2010.

Signature	Title
/s/ FRANK M. SEMPLE Frank M. Semple	President, Chief Executive Officer, Chairman of the Board and Director of MarkWest Energy GP, L.L.C., General Partner of MarkWest Energy Partners, L.P. (Principal Executive Officer)
/s/ NANCY K. BUESE Nancy K. Buese	Senior Vice President and Chief Financial Officer of MarkWest Energy GP, L.L.C., General Partner of MarkWest Energy Partners, L.P. (Principal Financial and Accounting Officer)
/s/ JOHN M. FOX John M. Fox	Lead Director of MarkWest Energy GP, L.L.C., General Partner of MarkWest Energy Partners, L.P.
/s/ KEITH E. BAILEY Keith E. Bailey	Director of MarkWest Energy GP, L.L.C., General Partner of MarkWest Energy Partners, L.P.
/s/ MICHAEL L. BEATTY Michael L. Beatty	Director of MarkWest Energy GP, L.L.C., General Partner of MarkWest Energy Partners, L.P.
/s/ CHARLES K. DEMPSTER Charles K. Dempster	Director of MarkWest Energy GP, L.L.C., General Partner of MarkWest Energy Partners, L.P.
/s/ DONALD C. HEPPERMAN Donald C. Hepperman	Director of MarkWest Energy GP, L.L.C., General Partner of MarkWest Energy Partners, L.P.
/s/ WILLIAM A. KELLSTROM William A. Kellstrom	Director of MarkWest Energy GP, L.L.C., General Partner of MarkWest Energy Partners, L.P.
/s/ ANNE E. FOX MOUNSEY Anne E. Fox Mounsey	Director of MarkWest Energy GP, L.L.C., General Partner of MarkWest Energy Partners, L.P.

II-18

Signature	Title
/s/ WILLIAM P. NICOLETTI William P. Nicoletti	Director of MarkWest Energy GP, L.L.C., General Partner of MarkWest Energy Partners, L.P.

II-19

SIGNATURES

        Pursuant to the requirements of the Securities Act of 1933, as amended, the registrant has duly caused this Registration Statement on Form S-3 to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Denver, State of Colorado, on the 13th day of January, 2010.

MARKWEST HYDROCARBON, INC.
By:	/s/ NANCY K. BUESE Nancy K. Buese Senior Vice President and Chief Financial Officer

        KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below constitutes and appoints Nancy K. Buese and Frank M. Semple, and each of them, his true and lawful attorneys-in-fact and agents, with full power of substitution, for him and in his name, place and stead, in any and all capacities, to sign any and all amendments (including post-effective amendments) to this registration statement and any additional registration statement pursuant to Rule 462(b), and to file the same with all exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents full power and authority to do and perform each and every act and thing requisite and necessary to be done in connection therewith, as fully and to all intents and purposes as they might or could not in person, hereby ratifying and confirming all that said attorneys-in-fact and agents or any of them, or their or his or her substitute or substitutes may lawfully do or cause to be done by virtue hereof.

        Pursuant to the requirements of the Securities Act of 1933, as amended, this Registration Statement on Form S-3 has been signed below by the following persons in the capacities indicated on the 13th day of January, 2010.

Signature	Title
/s/ FRANK M. SEMPLE Frank M. Semple	Chief Executive Officer, President and Director (Principal Executive Officer)
/s/ NANCY K. BUESE Nancy K. Buese	Senior Vice President, Chief Financial Officer and Director (Principal Financial and Accounting Officer)

II-20

SIGNATURES

        Pursuant to the requirements of the Securities Act of 1933, as amended, the registrant has duly caused this Registration Statement on Form S-3 to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Denver, State of Colorado, on the 13th day of January, 2010.

MASON PIPELINE LIMITED LIABILITY COMPANY
By:	MARKWEST HYDROCARBON, INC., its Sole Member
By:	/s/ NANCY K. BUESE Nancy K. Buese Senior Vice President and Chief Financial Officer

        KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below constitutes and appoints Nancy K. Buese and Frank M. Semple, and each of them, his true and lawful attorneys-in-fact and agents, with full power of substitution, for him and in his name, place and stead, in any and all capacities, to sign any and all amendments (including post-effective amendments) to this registration statement and any additional registration statement pursuant to Rule 462(b), and to file the same with all exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents full power and authority to do and perform each and every act and thing requisite and necessary to be done in connection therewith, as fully and to all intents and purposes as they might or could not in person, hereby ratifying and confirming all that said attorneys-in-fact and agents or any of them, or their or his or her substitute or substitutes may lawfully do or cause to be done by virtue hereof.

        Pursuant to the requirements of the Securities Act of 1933, as amended, this Registration Statement on Form S-3 has been signed below by the following persons in the capacities indicated on the 13th day of January, 2010.

Signature	Title
/s/ FRANK M. SEMPLE Frank M. Semple	Chief Executive Officer, President and Director (Principal Executive Officer)
/s/ NANCY K. BUESE Nancy K. Buese	Senior Vice President, Chief Financial Officer and Director (Principal Financial and Accounting Officer)

II-21

SIGNATURES

        Pursuant to the requirements of the Securities Act of 1933, as amended, the registrant has duly caused this Registration Statement on Form S-3 to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Denver, State of Colorado, on the 13th day of January, 2010.

MATREX, L.L.C.
By:	WEST SHORE PROCESSING COMPANY L.L.C., its Sole Member
By:	MARKWEST ENERGY OPERATING COMPANY, L.L.C., its Sole Member
By:	MARKWEST ENERGY PARTNERS, L.P., its Managing Member
By:	MARKWEST ENERGY GP, L.L.C., its General Partner
By:	/s/ NANCY K. BUESE Nancy K. Buese Senior Vice President and Chief Financial Officer

        KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below constitutes and appoints Nancy K. Buese and Frank M. Semple, and each of them, his true and lawful attorneys-in-fact and agents, with full power of substitution, for him and in his name, place and stead, in any and all capacities, to sign any and all amendments (including post-effective amendments) to this registration statement and any additional registration statement pursuant to Rule 462(b), and to file the same with all exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents full power and authority to do and perform each and every act and thing requisite and necessary to be done in connection therewith, as fully and to all intents and purposes as they might or could not in person, hereby ratifying and confirming all that said attorneys-in-fact and agents or any of them, or their or his or her substitute or substitutes may lawfully do or cause to be done by virtue hereof.

        Pursuant to the requirements of the Securities Act of 1933, as amended, this Registration Statement on Form S-3 has been signed below by the following persons in the capacities indicated on the 13th day of January, 2010.

Signature	Title
/s/ FRANK M. SEMPLE Frank M. Semple	President, Chief Executive Officer, Chairman of the Board and Director of MarkWest Energy GP, L.L.C., General Partner of MarkWest Energy Partners, L.P. (Principal Executive Officer)

II-22

Signature	Title
/s/ NANCY K. BUESE Nancy K. Buese	Senior Vice President and Chief Financial Officer of MarkWest Energy GP, L.L.C., General Partner of MarkWest Energy Partners, L.P. (Principal Financial Officer and Principal Accounting Officer)
/s/ JOHN M. FOX John M. Fox	Lead Director of MarkWest Energy GP, L.L.C., General Partner of MarkWest Energy Partners, L.P.
/s/ KEITH E. BAILEY Keith E. Bailey	Director of MarkWest Energy GP, L.L.C., General Partner of MarkWest Energy Partners, L.P.
/s/ MICHAEL L. BEATTY Michael L. Beatty	Director of MarkWest Energy GP, L.L.C., General Partner of MarkWest Energy Partners, L.P.
/s/ CHARLES K. DEMPSTER Charles K. Dempster	Director of MarkWest Energy GP, L.L.C., General Partner of MarkWest Energy Partners, L.P.
/s/ DONALD C. HEPPERMAN Donald C. Hepperman	Director of MarkWest Energy GP, L.L.C., General Partner of MarkWest Energy Partners, L.P.
/s/ WILLIAM A. KELLSTROM William A. Kellstrom	Director of MarkWest Energy GP, L.L.C., General Partner of MarkWest Energy Partners, L.P.
/s/ ANNE E. FOX MOUNSEY Anne E. Fox Mounsey	Director of MarkWest Energy GP, L.L.C., General Partner of MarkWest Energy Partners, L.P.
/s/ WILLIAM P. NICOLETTI William P. Nicoletti	Director of MarkWest Energy GP, L.L.C., General Partner of MarkWest Energy Partners, L.P.

II-23

Index of exhibits

Exhibit Number				Description
	1.1	*	—	Form of Underwriting Agreement
	2.1	(3)	—	Agreement and Plan of Redemption and Merger dated September 5, 2007 by and among MarkWest Hydrocarbon, Inc. MarkWest Energy Partners, L.P. and MWEP, L.L.C.
	4.1	(1)	—	Purchase Agreement dated October 19, 2004, among MarkWest Energy Partners, L.P., MarkWest Energy Finance Corporation, the Guarantors named therein and the Initial Purchasers named therein.
	4.2	(1)	—	Indenture dated as of October 25, 2004, among MarkWest Energy Partners, L.P., MarkWest Energy Finance Corporation, the Guarantors named therein and Wells Fargo Bank, National Association, as Trustee.
	4.3	(1)	—	Form of 6.875% Series A Senior Notes due 2014 with attached notation of Guarantees
	4.4	(5)	—	First Supplemental Indenture, dated as of February 2, 2005, among MarkWest Energy Partners, L.P., MarkWest Energy Finance Corporation, the Guarantors named therein and Wells Fargo Bank, National Association, as Trustee.
	4.5	(6)	—	Second Supplemental Indenture, dated as of January 17, 2006, among MarkWest Energy Partners, L.P., MarkWest Energy Finance Corporation, the Guarantors named therein and Wells Fargo Bank, National Association, as Trustee.
	4.6	(2)	—	Indenture dated as of July 6, 2006, among MarkWest Energy Partners, L.P., MarkWest Energy Finance Corporation, as Issuers, the Guarantors named therein, and Wells Fargo Bank, National Association, as Trustee.
	4.7	(2)	—	Form of 8.5% Series A and Series B Senior Notes due 2016 with attached notation of Guarantees (incorporated by Reference to Exhibits A and D of Exhibit 4.8 hereto).
	4.8	(7)	—	Third Supplemental Indenture, dated as of March 6, 2008, among MarkWest Energy Partners, L.P., MarkWest Energy Finance Corporation, the Guarantors named therein, and Wells Fargo Bank, National Association, as Trustee.
	4.9	(7)	—	First Supplemental Indenture, dated as of March 6, 2008, among MarkWest Energy Partners, L.P., MarkWest Energy Finance Corporation, the Guarantors named therein, and Wells Fargo Bank, National Association, as Trustee.
	4.10	(4)	—	Form of 83/4% Series A and Series B Senior Notes due 2018 with attached notation of Guarantees (incorporated by reference to Exhibits A and D of Exhibit 4.14 hereto).
	4.11	(4)	—	Indenture dated as of April 15, 2008 among MarkWest Energy Partners, L.P., MarkWest Energy Finance Corporation, and the several guarantors named therein, and Wells Fargo Bank, N.A., as trustee.
	4.12	(7)	—	Fourth Supplemental Indenture, dated as of April 25, 2008, among MarkWest Energy Partners, L.P., MarkWest Energy Finance Corporation, the Guarantors named therein, and Wells Fargo Bank, National Association, as Trustee.
	4.13	(7)	—	Second Supplemental Indenture, dated as of April 25, 2008, among MarkWest Energy Partners, L.P., MarkWest Energy Finance Corporation, the Guarantors named therein, and Wells Fargo Bank, National Association, as Trustee.
	4.14	(7)	—	First Supplemental Indenture, dated as of April 25, 2008, among MarkWest Energy Partners, L.P., MarkWest Energy Finance Corporation, the Guarantors named therein, and Wells Fargo Bank, National Association, as Trustee.

Exhibit Number				Description
	4.15	(7)	—	Fifth Supplemental Indenture, dated as of August 4, 2008, among MarkWest Energy Partners, L.P., MarkWest Energy Finance Corporation, the Guarantors named therein, and Wells Fargo Bank, National Association, as Trustee.
	4.16	(7)	—	Third Supplemental Indenture, dated as of August 4, 2008, among MarkWest Energy Partners, L.P., MarkWest Energy Finance Corporation, the Guarantors named therein, and Wells Fargo Bank, National Association, as Trustee.
	4.17	(7)	—	Second Supplemental Indenture, dated as of August 4, 2008, among MarkWest Energy Partners, L.P., MarkWest Energy Finance Corporation, the Guarantors named therein, and Wells Fargo Bank, National Association, as Trustee.
	4.18	(7)	—	Sixth Supplemental Indenture, dated as of September 15, 2008, among MarkWest Energy Partners, L.P., MarkWest Energy Finance Corporation, the Guarantors named therein, and Wells Fargo Bank, National Association, as Trustee.
	4.19	(7)	—	Fourth Supplemental Indenture, dated as of September 15, 2008, among MarkWest Energy Partners, L.P., MarkWest Energy Finance Corporation, the Guarantors named therein, and Wells Fargo Bank, National Association, as Trustee.
	4.20	(7)	—	Third Supplemental Indenture, dated as of September 15, 2008, among MarkWest Energy Partners, L.P., MarkWest Energy Finance Corporation, the Guarantors named therein, and Wells Fargo Bank, National Association, as Trustee.
	4.21	(8)	—	Indenture dated as of May 26, 2009 among MarkWest Energy Partners, L.P., MarkWest Energy Finance Corporation, and the several guarantors named therein, and Wells Fargo Bank, N.A., as Trustee.
	4.22	(9)	—	Indenture Release of Subsidiary Guarantor dated as of May 1, 2009 among MarkWest Energy Partners, L.P. and Wells Fargo Bank, N.A.
	4.23	**	—	Indenture Release of Subsidiary Guarantor dated as of October 31, 2009 among MarkWest Energy Partners, L.P. and Wells Fargo Bank, N.A.
	4.24	**	—	Form of Senior Indenture of MarkWest Energy Partners, L.P.
	4.25	**	—	Form of Subordinated Indenture of MarkWest Energy Partners, L.P
	5.1	**	—	Opinion of Vinson & Elkins L.L.P.
	8.1	**	—	Opinion of Vinson & Elkins L.L.P. relating to tax matters
	12.1	**	—	Computation of Ratio of Earnings to Fixed Charges.
	21.1	**	—	List of Subsidiaries.
	23.1	**	—	Consent of Deloitte & Touche LLP.
	23.2	**	—	Consent of PricewaterhouseCoopers LLP
	24.1	**	—	Power of Attorney (included on signature page of this registration statement)
	25.1	**	—	Form T-1 Statement of Eligibility and Qualification under the Trust Indenture Act of 1939 of the Trustee under the Senior Indenture
	25.2	**	—	Form T-1 Statement of Eligibility and Qualification under the Trust Indenture Act of 1939 of the Trustee under the Subordinated Indenture

(1)

Incorporated by reference to the Current Report on Form 8-K filed October 25, 2004.

(2)

Incorporated by reference to the Current Report on Form 8-K filed July 7, 2006.

(3)

Incorporated by reference to the Current Report on Form 8-K filed September 6, 2007.

(4)

Incorporated by reference to the Current Report on Form 8-K filed April 15, 2008.

(5)

Incorporated by reference to the Form S-4 Registration Statement filed February 22, 2005.

(6)

Incorporated by reference to the Form S-4/A Registration Statement filed January 17, 2006.

(7)

Incorporated by reference to the Annual Report on Form 10-K filed March 2, 2009.

(8)

Incorporated by reference to the Current Report on Form 8-K filed May 27, 2009.

(9)

Incorporated by reference to the Quarterly Report on Form 10-Q filed on August 10, 2009.

*

To be filed

**

Filed herewith.

EX-4.23

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EXHIBIT 4.23

ACKNOWLEDGEMENT OF RELEASE OF
SUBSIDIARY GUARANTOR
(Basin Pipeline L.L.C.)

October 31, 2009

        WELLS FARGO BANK, NATIONAL ASSOCIATION, acting as Trustee under each of the four Indentures among MarkWest Energy Partners, L.P., a Delaware limited partnership and MarkWest Energy Finance Corporation, a Delaware corporation, the Subsidiary Guarantors party thereto and the Trustee, dated as of October 25, 2004, July 6, 2006, April 15, 2008 and May 26, 2009, in each case as amended and supplemented to the date hereof (collectively, the "Indentures"), does hereby acknowledge that Basin Pipeline L.L.C, a Michigan limited liability company, has been released from its obligations under its Guarantees (including any guarantee notation endorsed on any Note issued under the Indentures) and the Indentures in accordance with the provisions of 10.05(ii) of each of the Indentures and has no continuing obligation or liability under its Guarantees or the Indentures whether arising before or after such releases.

        All capitalized terms used herein and not defined herein have the meanings attributed to them in the Indentures.

[REMAINDER OF PAGE INTENTIONALLY LEFT BLANK]

        IN WITNESS WHEREOF, the undersigned has executed this acknowledgment as of the date first written above.

WELLS FARGO BANK, NATIONAL ASSOCIATION, as Trustee
By:	/s/ PATRICK T. GIORDANO
Name:  Patrick T. Giordano Title:    Vice President

Signature Page to
Acknowledgment of Release of Subsidiary Guarantor
(Basin Pipeline L.L.C.)

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EXHIBIT 4.23

ACKNOWLEDGEMENT OF RELEASE OF SUBSIDIARY GUARANTOR (Basin Pipeline L.L.C.)

EX-4.24

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Exhibit 4.24

[Form of Senior Indenture]

MARKWEST ENERGY PARTNERS, L.P.
as Issuer,
any Subsidiary Guarantors party hereto,
and
[                        ],
as Trustee
INDENTURE
Dated as of
Debt Securities

CROSS-REFERENCE TABLE

	TIA Section			Indenture Section
310		(a	)	7.10
		(b	)	7.10
		(c	)	N.A.
311		(a	)	7.11
		(b	)	7.11
		(c	)	N.A.
312		(a	)	5.01
		(b	)	5.02
		(c	)	5.02
313		(a	)	5.03
		(b	)	5.03
		(c	)	13.03
		(d	)	5.03
314		(a	)	4.05
		(b	)	N.A.
		(c	)(1)	13.05
		(c	)(2)	13.05
		(c	)(3)	N.A.
		(d	)	N.A.
		(e	)	13.05
		(f	)	N.A.
315		(a	)	7.01
		(b	)	6.07 & 13.03
		(c	)	7.01
		(d	)	7.01
		(e	)	6.08
316		(a	) (last sentence)	1.01
		(a	)(1)(A)	6.06
		(a	)(1)(B)	6.06
		(a	)(2)	9.01(d)
		(b	)	6.04
		(c	)	5.04
317		(a	)(1)	6.02
		(a	)(2)	6.02
		(b	)	4.04
318		(a	)	13.07

N.A. means Not Applicable

NOTE: This Cross-Reference table shall not, for any purpose, be deemed part of this Indenture.

i

TABLE OF CONTENTS

ARTICLE I DEFINITIONS AND INCORPORATION BY REFERENCE
Section 1.01	Definitions	1
Section 1.02	Other Definitions	5
Section 1.03	Incorporation by Reference of Trust Indenture Act	5
Section 1.04	Rules of Construction	5
ARTICLE II DEBT SECURITIES
Section 2.01	Forms Generally	6
Section 2.02	Form of Trustee's Certificate of Authentication	6
Section 2.03	Principal Amount; Issuable in Series	6
Section 2.04	Execution of Debt Securities	8
Section 2.05	Authentication and Delivery of Debt Securities	8
Section 2.06	Denomination of Debt Securities	10
Section 2.07	Registration of Transfer and Exchange	10
Section 2.08	Temporary Debt Securities	11
Section 2.09	Mutilated, Destroyed, Lost or Stolen Debt Securities	11
Section 2.10	Cancellation of Surrendered Debt Securities	12
Section 2.11	Provisions of the Indenture and Debt Securities for the Sole Benefit of the Parties and the Holders	12
Section 2.12	Payment of Interest; Interest Rights Preserved	12
Section 2.13	Securities Denominated in Dollars	13
Section 2.14	Wire Transfers	13
Section 2.15	Securities Issuable in the Form of a Global Security	13
Section 2.16	Medium Term Securities	15
Section 2.17	Defaulted Interest	15
Section 2.18	CUSIP Numbers	16
ARTICLE III REDEMPTION OF DEBT SECURITIES
Section 3.01	Applicability of Article	16
Section 3.02	Notice of Redemption; Selection of Debt Securities	16
Section 3.03	Payment of Debt Securities Called for Redemption	17
Section 3.04	Mandatory and Optional Sinking Funds	18
Section 3.05	Redemption of Debt Securities for Sinking Fund	18
ARTICLE IV PARTICULAR COVENANTS OF THE COMPANY
Section 4.01	Payment of Principal of, and Premium, If Any, and Interest on, Debt Securities	20
Section 4.02	Maintenance of Offices or Agencies for Registration of Transfer, Exchange and Payment of Debt Securities	20
Section 4.03	Appointment to Fill a Vacancy in the Office of Trustee	20
Section 4.04	Duties of Paying Agents, etc	20
Section 4.05	SEC Reports; Financial Statements	21
Section 4.06	Compliance Certificate	22
Section 4.07	Further Instruments and Acts	22
Section 4.08	Existence	22
Section 4.09	Maintenance of Properties	22

ii

Section 4.10	Payment of Taxes and Other Claims	22
Section 4.11	Waiver of Certain Covenants	23
ARTICLE V HOLDERS' LISTS AND REPORTS BY THE TRUSTEE
Section 5.01	Partnership to Furnish Trustee Information as to Names and Addresses of Holders; Preservation of Information	23
Section 5.02	Communications to Holders	23
Section 5.03	Reports by Trustee	23
Section 5.04	Record Dates for Action by Holders	24
ARTICLE VI REMEDIES OF THE TRUSTEE AND HOLDERS IN EVENT OF DEFAULT
Section 6.01	Events of Default	24
Section 6.02	Collection of Debt by Trustee, etc	26
Section 6.03	Application of Moneys Collected by Trustee	27
Section 6.04	Limitation on Suits by Holders	27
Section 6.05	Remedies Cumulative; Delay or Omission in Exercise of Rights Not a Waiver of Default	28
Section 6.06	Rights of Holders of Majority in Principal Amount of Debt Securities to Direct Trustee and to Waive Default	28
Section 6.07	Trustee to Give Notice of Events of Defaults Known to It, but May Withhold Such Notice in Certain Circumstances	29
Section 6.08	Requirement of an Undertaking to Pay Costs in Certain Suits under the Indenture or Against the Trustee	29
ARTICLE VII CONCERNING THE TRUSTEE
Section 7.01	Certain Duties and Responsibilities	29
Section 7.02	Certain Rights of Trustee	30
Section 7.03	Trustee Not Liable for Recitals in Indenture or in Debt Securities	31
Section 7.04	Trustee, Paying Agent or Registrar May Own Debt Securities	31
Section 7.05	Moneys Received by Trustee to Be Held in Trust	32
Section 7.06	Compensation and Reimbursement	32
Section 7.07	Right of Trustee to Rely on an Officers' Certificate Where No Other Evidence Specifically Prescribed	32
Section 7.08	Separate Trustee; Replacement of Trustee	32
Section 7.09	Successor Trustee by Merger	33
Section 7.10	Eligibility; Disqualification	34
Section 7.11	Preferential Collection of Claims Against Partnership	34
Section 7.12	Compliance with Tax Laws	34
ARTICLE VIII CONCERNING THE HOLDERS
Section 8.01	Evidence of Action by Holders	34
Section 8.02	Proof of Execution of Instruments and of Holding of Debt Securities	34
Section 8.03	Who May Be Deemed Owner of Debt Securities	34
Section 8.04	Instruments Executed by Holders Bind Future Holders	35
ARTICLE IX SUPPLEMENTAL INDENTURES
Section 9.01	Purposes for Which Supplemental Indenture May Be Entered into Without Consent of Holders	35

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Section 9.02	Modification of Indenture with Consent of Holders of Debt Securities	37
Section 9.03	Effect of Supplemental Indentures	38
Section 9.04	Debt Securities May Bear Notation of Changes by Supplemental Indentures	38
ARTICLE X CONSOLIDATION, MERGER, SALE OR CONVEYANCE
Section 10.01	Consolidations and Mergers of the Partnership	38
Section 10.02	Rights and Duties of Successor Partnership	38
ARTICLE XI SATISFACTION AND DISCHARGE OF INDENTURE; DEFEASANCE; UNCLAIMED MONEYS
Section 11.01	Applicability of Article	39
Section 11.02	Satisfaction and Discharge of Indenture; Defeasance	39
Section 11.03	Conditions of Defeasance	40
Section 11.04	Application of Trust Money	41
Section 11.05	Repayment to Partnership	41
Section 11.06	Indemnity for U.S. Government Obligations	41
Section 11.07	Reinstatement	41
ARTICLE XII [RESERVED]
ARTICLE XIII MISCELLANEOUS PROVISIONS
Section 13.01	Successors and Assigns of Partnership Bound by Indenture	42
Section 13.02	Acts of Board, Committee or Officer of Successor Partnership Valid	42
Section 13.03	Required Notices or Demands	42
Section 13.04	Indenture and Debt Securities to Be Construed in Accordance with the Laws of the State of New York	43
Section 13.05	Officers' Certificate and Opinion of Counsel to Be Furnished upon Application or Demand by the Partnership	43
Section 13.06	Payments Due on Legal Holidays	43
Section 13.07	Provisions Required by TIA to Control	43
Section 13.08	Computation of Interest on Debt Securities	43
Section 13.09	Rules by Trustee, Paying Agent and Registrar	43
Section 13.10	No Recourse Against Others	43
Section 13.11	Severability	44
Section 13.12	Effect of Headings	44
Section 13.13	Indenture May Be Executed in Counterparts	44
ARTICLE XIV GUARANTEE
Section 14.01	Unconditional Guarantee	44
Section 14.02	Execution and Delivery of Guarantee	46
Section 14.03	Limitation on Subsidiary Guarantors' Liability	46
Section 14.04	Release of Subsidiary Guarantors from Guarantee	46
Section 14.05	Subsidiary Guarantor Contribution	47
Notation of Guarantee	Annex A

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        THIS INDENTURE dated as of [            ] is among MarkWest Energy Partners, L.P., a Delaware limited partnership (the "Partnership"), any Subsidiary Guarantors (as defined herein) party hereto, and [            ], a, as trustee (the "Trustee").

RECITALS OF THE COMPANY AND ANY SUBSIDIARY GUARANTORS

        The Partnership and any Subsidiary Guarantors have duly authorized the execution and delivery of this Indenture to provide for the issuance from time to time of the Partnership's debentures, notes, bonds or other evidences of indebtedness to be issued in one or more series unlimited as to principal amount (herein called the "Debt Securities"), which Debt Securities may be guaranteed by each of the Subsidiary Guarantors, as in this Indenture provided.

        All things necessary to make this Indenture a valid agreement of the Partnership and any Subsidiary Guarantors, in accordance with its terms, have been done.

NOW, THEREFORE, THIS INDENTURE WITNESSETH

        That in order to declare the terms and conditions upon which the Debt Securities are authenticated, issued and delivered, and in consideration of the premises, and of the purchase and acceptance of the Debt Securities by the Holders thereof, the Partnership, any Subsidiary Guarantor and the Trustee covenant and agree with each other, for the benefit of the respective Holders from time to time of the Debt Securities or any series thereof, as follows:

ARTICLE I

DEFINITIONS AND INCORPORATION BY REFERENCE

        Section 1.01 Definitions.

        "Affiliate" of any specified Person means any other Person directly or indirectly controlling or controlled by or under direct or indirect common control with such specified Person. For the purposes of this definition, "control" when used with respect to any specified Person means the power to direct the management and policies of such Person, directly or indirectly, whether through the ownership of voting securities, by contract or otherwise; and the terms "controlling" and "controlled" have meanings correlative to the foregoing. The Trustee may request and may conclusively rely upon an Officers' Certificate to determine whether any Person is an Affiliate of any specified Person.

        "Agent" means any Registrar or paying agent.

        "Bankruptcy Law" means Title 11, U.S. Code or any similar federal or state law for the relief of debtors.

        "Board of Directors" means the Board of Directors of the general partner of the Partnership or any authorized committee of the Board of Directors of the general partner of the Partnership or any directors and/or officers of the Partnership to whom such Board of Directors or such committee shall have duly delegated its authority to act hereunder. If the Partnership shall change its form of entity to other than a limited Partnership, the references to the Board of Directors of the general partner of the Partnership]shall mean the Board of Directors (or other comparable governing body) of the Partnership.

        "Business Day" means any day other than a Legal Holiday.

        "Capital stock" of any Person means and includes any and all shares, rights to purchase, warrants or options (whether or not currently exercisable), participations or other equivalents of or interests in (however designated) the equity (which includes, but is not limited to, common stock, preferred stock and Partnership and joint venture interests) of such Person (excluding any debt securities that are convertible into, or exchangeable for, such equity).

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        "Custodian" means any receiver, trustee, assignee, liquidator or similar official under any Bankruptcy Law.

        "Debt" of any Person at any date means any obligation created or assumed by such Person for the repayment of borrowed money and any guarantee thereof.

        "Debt Security" or "Debt Securities" has the meaning stated in the first recital of this Indenture and more particularly means any debt security or debt securities, as the case may be, of any series authenticated and delivered under this Indenture.

        "Default" means any event, act or condition that is, or after notice or the passage of time or both would be, an Event of Default.

        "Depositary" means, unless otherwise specified by the Partnership pursuant to either Section 2.03 or 2.15, with respect to Debt Securities of any series issuable or issued in whole or in part in the form of one or more Global Securities, The Depository Trust Partnership, New York, New York, or any successor thereto registered as a clearing agency under the Exchange Act or other applicable statute or regulations.

        "Dollar" or "$" means such currency of the United States as at the time of payment is legal tender for the payment of public and private debts.

        "Exchange Act" means the Securities Exchange Act of 1934, as amended, and any successor statute.

        "Floating Rate Security" means a Debt Security that provides for the payment of interest at a variable rate determined periodically by reference to an interest rate index specified pursuant to Section 2.03.

        "GAAP" means generally accepted accounting principles in the United States, as in effect from time to time.

        "Global Security" means with respect to any series of Debt Securities issued hereunder, a Debt Security which is executed by the Partnership and authenticated and delivered by the Trustee to the Depositary or pursuant to the Depositary's instruction, all in accordance with this Indenture and any Indentures supplemental hereto, or resolution of the Board of Directors and set forth in an Officers' Certificate, which shall be registered in the name of the Depositary or its nominee and which shall represent, and shall be denominated in an amount equal to the aggregate principal amount of, all the Outstanding Debt Securities of such series or any portion thereof, in either case having the same terms, including, without limitation, the same original issue date, date or dates on which principal is due and interest rate or method of determining interest.

        "guarantee" means any obligation, contingent or otherwise, of any Person directly or indirectly guaranteeing any Debt or other obligation of any other Person and any obligation, direct or indirect, contingent or otherwise, of such Person (a) to purchase or pay (or advance or supply funds for the purchase or payment of) such Debt or other obligation of such other Person (whether arising by virtue of Partnership arrangements, or by agreement to keep-well, to purchase assets, goods, securities or services, to take-or-pay, or to maintain financial statement conditions or otherwise) or (b) entered into for purposes of assuring in any other manner the obligee of such Debt or other obligation of the payment thereof or to protect such obligee against loss in respect thereof (in whole or in part); provided, however, that the term "guarantee" shall not include endorsements for collection or deposit in the ordinary course of business. The term "guarantee" used as a verb has a corresponding meaning.

        "Holder," "Holder of Debt Securities" or other similar terms means, a Person in whose name a Debt Security is registered in the Debt Security Register (as defined in Section 2.07(a)).

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        "Indenture" means this instrument as originally executed, or, if amended or supplemented as herein provided, as so amended or supplemented and shall include the form and terms of particular series of Debt Securities as contemplated hereunder, whether or not a supplemental Indenture is entered into with respect thereto.

        "Legal Holiday" means a Saturday, a Sunday or a day on which banking institutions in the City of Houston, Texas, City of New York, New York or at a Place of Payment are authorized by law, regulation or executive order to remain closed. If a payment date is a Legal Holiday at a Place of Payment, payment may be made at that place on the next succeeding day that is not a Legal Holiday, and no interest shall accrue for the intervening period.

        "Lien" means, with respect to any asset, any mortgage, lien, security interest, pledge, charge or other encumbrance of any kind in respect of such asset, whether or not filed, recorded or otherwise perfected under applicable law.

        "Officer" means, with respect to a Person, the Chairman of the Board, the President, any Vice President, the Treasurer, any Assistant Treasurer, Controller, Secretary or any Assistant Secretary of such Person.

        "Officers' Certificate" means a certificate signed by two Officers of the Partnership, one of whom must be the Partnership's chief executive officer, chief financial officer or chief accounting officer (or if the Partnership shall change its form of entity to other than a limited Partnership, by Persons, officers, members, agents and others holding positions comparable to those of the foregoing nature, as applicable).

        "Opinion of Counsel" means a written opinion from legal counsel who is acceptable to the Trustee. The counsel may be an employee of or counsel to the Partnership or the Trustee.

        "Original Issue Discount Debt Security" means any Debt Security which provides for an amount less than the principal amount thereof to be due and payable upon a declaration of acceleration of the maturity thereof pursuant to Section 6.01.

        "Outstanding," when used with respect to any series of Debt Securities, means, as of the date of determination, all Debt Securities of that series theretofore authenticated and delivered under this Indenture, except:

        (a)   Debt Securities of that series theretofore canceled by the Trustee or delivered to the Trustee for cancellation;

        (b)   Debt Securities of that series for whose payment or redemption money in the necessary amount has been theretofore deposited with the Trustee or any paying agent (other than the Partnership) in trust or set aside and segregated in trust by the Partnership (if the Partnership shall act as its own paying agent) for the Holders of such Debt Securities; provided, that, if such Debt Securities are to be redeemed, notice of such redemption has been duly given pursuant to this Indenture or provision therefor satisfactory to the Trustee has been made; and

        (c)   Debt Securities of that series which have been paid pursuant to Section 2.09 or in exchange for or in lieu of which other Debt Securities have been authenticated and delivered pursuant to this Indenture, other than any such Debt Securities in respect of which there shall have been presented to the Trustee proof satisfactory to it that such Debt Securities are held by a bona fide purchaser in whose hands such Debt Securities are valid obligations of the Partnership;

provided, however, that in determining whether the Holders of the requisite principal amount of the Outstanding Debt Securities of any series have given any request, demand, authorization, direction, notice, consent or waiver hereunder, Debt Securities owned by the Partnership or any other obligor upon the Debt Securities or any Affiliate of the Partnership or of such other obligor shall be

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disregarded and deemed not to be Outstanding, except that, in determining whether the Trustee shall be protected in relying upon any such request, demand, authorization, direction, notice, consent or waiver, only Debt Securities which a Trust Officer actually knows to be so owned shall be so disregarded. Debt Securities so owned which have been pledged in good faith may be regarded as Outstanding if the pledgee establishes to the satisfaction of the Trustee the pledgee's right so to act with respect to such Debt Securities and that the pledgee is not the Partnership or any other obligor upon the Debt Securities or an Affiliate of the Partnership or of such other obligor. In determining whether the Holders of the requisite principal amount of Outstanding Debt Securities have given any request, demand, authorization, direction, notice, consent or waiver hereunder, the principal amount of an Original Issue Discount Debt Security that shall be deemed to be Outstanding for such purposes shall be the amount of the principal thereof that would be due and payable as of the date of such determination upon a declaration of acceleration of the maturity thereof pursuant to Section 6.01.

        "Partnership" means MarkWest Energy Partners, L.P., a Delaware limited partnership, and its successor.

        "Partnership Order" means a written request or order signed in the name of the Partnership by the Chairman of the Board, the President or a Vice President of the Partnership, and by the Treasurer, an Assistant Treasurer, the Controller, an Assistant Controller, the Secretary or an Assistant Secretary of the Partnership] and delivered to the Trustee, or if the Partnership shall change its form of entity to other than a limited Partnership, by Persons or officers, members, agents and others holding positions comparable to those of the foregoing nature, as applicable.

        "Person" means any individual, corporation, Partnership, joint venture, limited liability company, incorporated or unincorporated association, joint-stock company, trust, unincorporated organization or government or other agency or political subdivision thereof or other entity of any kind.

        "Redemption Date," when used with respect to any Debt Security to be redeemed, means the date fixed for such redemption by or pursuant to this Indenture.

        "SEC" means the Securities and Exchange Commission.

        "Securities Act" means the Securities Act of 1933, as amended, and any successor statute.

        "Stated Maturity" means, with respect to any security, the date specified in such security as the fixed date on which the payment of principal of such security is due and payable, including pursuant to any mandatory redemption provision (but excluding any provision providing for the repurchase of such security at the option of the holder thereof upon the happening of any contingency beyond the control of the issuer unless such contingency has occurred).

        "Subsidiary" of any Person means any corporation, association or other business entity of which more than 50% of the total voting power of equity interests entitled, without regard to the occurrence of any contingency, to vote in the election of directors, managers, trustees or equivalent Persons thereof is at the time of determination owned or controlled, directly or indirectly, by such Person or one or more of the other Subsidiaries of such Person or combination thereof.

        "Subsidiary Guarantors" means any Subsidiary of the Partnership who may execute this Indenture, or a supplement hereto, for the purpose of providing a Guarantee of Debt Securities pursuant to this Indenture until a successor Person shall have become such pursuant to the applicable provisions of this Indenture, and thereafter "Subsidiary Guarantors" shall mean such successor Person.

        "TIA" means the Trust Indenture Act of 1939, as amended (15 U.S.C. §§77aaa-77bbbb), as in effect on the date of this Indenture as originally executed and, to the extent required by law, as amended.

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        "Trustee" initially means [            ] and any other Person or Persons appointed as such from time to time pursuant to Section 7.08, and, subject to the provisions of Article VII, includes its or their successors and assigns. If at any time there is more than one such Person, "Trustee" as used with respect to the Debt Securities of any series shall mean the Trustee with respect to the Debt Securities of that series.

        "Trust Officer" means any officer or assistant officer of the Trustee assigned by the Trustee to administer its corporate trust matters.

        "United States" means the United States of America (including the States and the District of Columbia), its territories, its possessions and other areas subject to its jurisdiction.

        "U.S. Government Obligations" means direct obligations of the United States of America, obligations on which the payment of principal and interest is fully guaranteed by the United States of America or obligations or guarantees for the payment of which the full faith and credit of the United States of America is pledged.

        "Yield to Maturity" means the yield to maturity, calculated at the time of issuance of a series of Debt Securities, or, if applicable, at the most recent redetermination of interest on such series and calculated in accordance with accepted financial practice.

        Section 1.02 Other Definitions.

Term	Defined in Section
"Debt Security Register"		2.07
"Defaulted Interest"		2.17
"Event of Default"		6.01
"Funding Guarantor"		14.05
"Guarantee"		14.01
"Place of Payment"		2.03
"Registrar"		2.07
"Successor Partnership"		10.01

        Section 1.03 Incorporation by Reference of Trust Indenture Act. Whenever this Indenture refers to a provision of the TIA, the provision is incorporated by reference in and made a part of this Indenture.

        All terms used in this Indenture that are defined by the TIA, defined by TIA reference to another statute or defined by SEC rule under the TIA have the meanings so assigned to them.

        Section 1.04 Rules of Construction. Unless the context otherwise requires:

        (a)   a term has the meaning assigned to it;

        (b)   an accounting term not otherwise defined has the meaning assigned to it in accordance with GAAP;

        (c)   "or" is not exclusive;

        (d)   words in the singular include the plural, and in the plural include the singular;

        (e)   provisions apply to successive events and transactions; and

        (f)    the principal amount of any noninterest bearing or other discount security at any date shall be the principal amount thereof that would be shown on a balance sheet of the issuer dated such date prepared in accordance with GAAP.

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ARTICLE II

DEBT SECURITIES

        Section 2.01 Forms Generally. The Debt Securities of each series shall be in substantially the form established without the approval of any Holder by or pursuant to a resolution of the Board of Directors or in one or more Indentures supplemental hereto, in each case with such appropriate insertions, omissions, substitutions and other variations as are required or permitted by this Indenture, and may have such letters, numbers or other marks of identification and such legends or endorsements placed thereon as the Partnership may deem appropriate (and, if not contained in a supplemental Indenture entered into in accordance with Article IX, as are not prohibited by the provisions of this Indenture) or as may be required or appropriate to comply with any law or with any rules made pursuant thereto or with any rules of any securities exchange on which such series of Debt Securities may be listed, or to conform to general usage, or as may, consistently herewith, be determined by the officers executing such Debt Securities as evidenced by their execution of the Debt Securities.

        The definitive Debt Securities of each series shall be printed, lithographed or engraved on steel engraved borders or may be produced in any other manner, all as determined by the officers executing such Debt Securities, as evidenced by their execution of such Debt Securities.

        Section 2.02 Form of Trustee's Certificate of Authentication. The Trustee's certificate of authentication on all Debt Securities authenticated by the Trustee shall be in substantially the following form:

TRUSTEE'S CERTIFICATE OF AUTHENTICATION

        This is one of the Debt Securities of the series designated therein referred to in the within-mentioned Indenture.

[			],
	As Trustee
	By:
		Authorized Signatory

        Section 2.03 Principal Amount; Issuable in Series. The aggregate principal amount of Debt Securities which may be issued, executed, authenticated, delivered and outstanding under this Indenture is unlimited.

        The Debt Securities may be issued in one or more series in fully registered form. There shall be established, without the approval of any Holders, in or pursuant to a resolution of the Board of Directors and set forth in an Officers' Certificate, or established in one or more Indentures supplemental hereto, prior to the issuance of Debt Securities of any series any or all of the following:

        (a)   the title of the Debt Securities of the series (which shall distinguish the Debt Securities of the series from all other Debt Securities);

        (b)   any limit upon the aggregate principal amount of the Debt Securities of the series which may be authenticated and delivered under this Indenture (except for Debt Securities authenticated and delivered upon registration of transfer of, or in exchange for, or in lieu of, other Debt Securities of the series pursuant to this Article II);

        (c)   the date or dates on which the principal of and premium, if any, on the Debt Securities of the series are payable;

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        (d)   the rate or rates (which may be fixed or variable) at which the Debt Securities of the series shall bear interest, if any, or the method of determining such rate or rates, the date or dates from which such interest shall accrue, the interest payment dates on which such interest shall be payable, or the method by which such date will be determined, the record dates for the determination of Holders thereof to whom such interest is payable; and the basis upon which interest will be calculated if other than that of a 360-day year of twelve thirty-day months;

        (e)   the place or places, if any, in addition to or instead of the corporate trust office of the Trustee, where the principal of, and premium, if any, and interest on, Debt Securities of the series shall be payable ("Place of Payment");

        (f)    the price or prices at which, the period or periods within which and the terms and conditions upon which Debt Securities of the series may be redeemed, in whole or in part, at the option of the Partnership or otherwise;

        (g)   whether Debt Securities of the series are entitled to the benefits of any Guarantee of any Subsidiary Guarantors pursuant to this Indenture;

        (h)   the obligation, if any, of the Partnership to redeem, purchase or repay Debt Securities of the series pursuant to any sinking fund or analogous provisions or at the option of a Holder thereof, and the price or prices at which and the period or periods within which and the terms and conditions upon which Debt Securities of the series shall be redeemed, purchased or repaid, in whole or in part, pursuant to such obligations;

        (i)    the terms, if any, upon which the Debt Securities of the series may be convertible into or exchanged for capital stock (which may be represented by depositary shares), other Debt Securities or warrants for capital stock or Debt or other securities of any kind of the Partnership or any other obligor and the terms and conditions upon which such conversion or exchange shall be effected, including the initial conversion or exchange price or rate, the conversion or exchange period and any other provision in addition to or in lieu of those described herein;

        (j)    if other than denominations of $1,000 and any integral multiple thereof, the denominations in which Debt Securities of the series shall be issuable;

        (k)   if the amount of principal of or any premium or interest on Debt Securities of the series may be determined with reference to an index or pursuant to a formula, the manner in which such amounts will be determined;

        (l)    if the principal amount payable at the Stated Maturity of Debt Securities of the series will not be determinable as of any one or more dates prior to such Stated Maturity, the amount which will be deemed to be such principal amount as of any such date for any purpose, including the principal amount thereof which will be due and payable upon any maturity other than the Stated Maturity or which will be deemed to be Outstanding as of any such date (or, in any such case, the manner in which such deemed principal amount is to be determined);

        (m)  any changes or additions to Article XI, including the addition of additional covenants that may be subject to the covenant defeasance option pursuant to Section 11.02(b);

        (n)   if other than the principal amount thereof, the portion of the principal amount of Debt Securities of the series which shall be payable upon declaration of acceleration of the maturity thereof pursuant to Section 6.01 or provable in bankruptcy pursuant to Section 6.02;

        (o)   the terms, if any, of the transfer, mortgage, pledge or assignment as security for the Debt Securities of the series of any properties, assets, moneys, proceeds, securities or other collateral, including whether certain provisions of the TIA are applicable and any corresponding changes to provisions of this Indenture as currently in effect;

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        (p)   any addition to or change in the Events of Default with respect to the Debt Securities of the series and any change in the right of the Trustee or the Holders to declare the principal of, and premium and interest on, such Debt Securities due and payable;

        (q)   if the Debt Securities of the series shall be issued in whole or in part in the form of a Global Security or Securities, the terms and conditions, if any, upon which such Global Security or Securities may be exchanged in whole or in part for other individual Debt Securities in definitive registered form; and the Depositary for such Global Security or Securities and the form of any legend or legends to be borne by any such Global Security or Securities in addition to or in lieu of the legend referred to in Section 2.15(a);

        (r)   any trustees, authenticating or paying agents, transfer agents or registrars;

        (s)   the applicability of, and any addition to or change in the covenants and definitions currently set forth in this Indenture or in the terms currently set forth in Article X, including conditioning any merger, conveyance, transfer or lease permitted by Article X upon the satisfaction of any Debt coverage standard by the Partnership and Successor Partnership (as defined in Article X);

        (t)    with regard to Debt Securities of the series that do not bear interest, the dates for certain required reports to the Trustee; and

        (u)   any other terms of the Debt Securities of the series (which terms shall not be prohibited by the provisions of this Indenture).

        All Debt Securities of any one series shall be substantially identical except as to denomination and except as may otherwise be provided in or pursuant to such resolution of the Board of Directors and as set forth in such Officers' Certificate or in any such Indenture supplemental hereto.

        Section 2.04 Execution of Debt Securities. The Debt Securities shall be signed on behalf of the Partnership by the Chairman of the Board, the President or a Vice President of the Partnership and, if the seal of the Partnership is reproduced thereon, it shall be attested by its Secretary, an Assistant Secretary, a Treasurer or an Assistant Treasurer. Such signatures upon the Debt Securities may be the manual or facsimile signatures of the present or any future such authorized officers and may be imprinted or otherwise reproduced on the Debt Securities. The seal of the Partnership, if any, may be in the form of a facsimile thereof and may be impressed, affixed, imprinted or otherwise reproduced on the Debt Securities.

        Only such Debt Securities as shall bear thereon a certificate of authentication substantially in the form hereinbefore recited, signed manually by the Trustee, shall be entitled to the benefits of this Indenture or be valid or obligatory for any purpose. Such certificate by the Trustee upon any Debt Security executed by the Partnership on behalf of the Partnership shall be conclusive evidence that the Debt Security so authenticated has been duly authenticated and delivered hereunder.

        In case any officer of the Partnership who shall have signed any of the Debt Securities shall cease to be such officer before the Debt Securities so signed shall have been authenticated and delivered by the Trustee, or disposed of by the Partnership, such Debt Securities nevertheless may be authenticated and delivered or disposed of as though the Person who signed such Debt Securities had not ceased to be such officer of the Partnership; and any Debt Security may be signed on behalf of the Partnership by such Persons as, at the actual date of the execution of such Debt Security, shall be the proper officers of the Partnership, although at the date of such Debt Security or of the execution of this Indenture any such Person was not such officer.

        Section 2.05 Authentication and Delivery of Debt Securities. At any time and from time to time after the execution and delivery of this Indenture, the Partnership may deliver to the Trustee for authentication Debt Securities of any series executed by the Partnership, and the Trustee shall thereupon authenticate and deliver said Debt Securities to or upon a Partnership Order. In

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authenticating such Debt Securities, and accepting the additional responsibilities under this Indenture in relation to such Debt Securities, the Trustee shall be entitled to receive, and (subject to Section 7.01) shall be fully protected in relying upon:

        (a)   a copy of any resolution or resolutions of the Board of Directors, certified by the Secretary or Assistant Secretary of the Partnership, authorizing the terms of issuance of any series of Debt Securities;

        (b)   an executed supplemental Indenture, if any;

        (c)   an Officers' Certificate; and

        (d)   an Opinion of Counsel prepared in accordance with Section 13.05 which shall also state:

        (i)    that the form of such Debt Securities has been established by or pursuant to a resolution of the Board of Directors or by a supplemental Indenture as permitted by Section 2.01 in conformity with the provisions of this Indenture;

        (ii)   that the terms of such Debt Securities have been established by or pursuant to a resolution of the Board of Directors or by a supplemental Indenture as permitted by Section 2.03 in conformity with the provisions of this Indenture;

        (iii)  (that such Debt Securities, when authenticated and delivered by the Trustee and issued by the Partnership in the manner and subject to any conditions specified in such Opinion of Counsel, will constitute valid and legally binding obligations of the Partnership, enforceable in accordance with their terms except as the enforceability thereof may be limited by bankruptcy, insolvency or similar laws affecting the enforcement of creditors' rights generally and rights of acceleration and the availability of equitable remedies may be limited by equitable principles of general applicability;

        (iv)  that the Partnership has the Partnership power to issue such Debt Securities and has duly taken all necessary Partnership action with respect to such issuance;

        (v)   that the issuance of such Debt Securities will not contravene the organizational documents of the Partnership or result in any material violation of any of the terms or provisions of any law or regulation or of any material indenture, mortgage or other agreement known to such counsel by which the Partnership is bound;

        (vi)  that authentication and delivery of such Debt Securities and the execution and delivery of any supplemental Indenture will not violate the terms of this Indenture; and

        (vii) such other matters as the Trustee may reasonably request.

        Such Opinion of Counsel need express no opinion as to whether a court in the United States would render a money judgment in a currency other than that of the United States.

        The Trustee shall have the right to decline to authenticate and deliver any Debt Securities under this Section 2.05 if the Trustee, being advised by counsel, determines that such action may not lawfully be taken or if the Trustee in good faith by its board of directors or trustees, executive committee or a trust committee of directors, trustees or Officers (or any combination thereof) shall determine that such action would expose the Trustee to personal liability to existing Holders.

        The Trustee may appoint an authenticating agent reasonably acceptable to the Partnership to authenticate Debt Securities of any series. Unless limited by the terms of such appointment, an authenticating agent may authenticate Debt Securities whenever the Trustee may do so. Each reference in this Indenture to authentication by the Trustee includes authentication by such agent. An authenticating agent has the same rights as any Registrar, paying agent or agent for service of notices and demands.

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        Unless otherwise provided in the form of Debt Security for any series, each Debt Security shall be dated the date of its authentication.

        Section 2.06 Denomination of Debt Securities. Unless otherwise provided in the form of Debt Security for any series, the Debt Securities of each series shall be issuable only as fully registered Debt Securities in such Dollar denominations as shall be specified or contemplated by Section 2.03. In the absence of any such specification with respect to the Debt Securities of any series, the Debt Securities of such series shall be issuable in denominations of $1,000 and any integral multiple thereof.

        Section 2.07 Registration of Transfer and Exchange.

        (a)   The Partnership shall keep or cause to be kept a register for each series of Debt Securities issued hereunder (hereinafter collectively referred to as the "Debt Security Register"), in which, subject to such reasonable regulations as it may prescribe, the Partnership shall provide for the registration of all Debt Securities and the transfer of Debt Securities as in this Article II provided. At all reasonable times the Debt Security Register shall be open for inspection by the Trustee. Subject to Section 2.15, upon due presentment for registration of transfer of any Debt Security at any office or agency to be maintained by the Partnership in accordance with the provisions of Section 4.02, the Partnership shall execute and the Trustee shall authenticate and deliver in the name of the transferee or transferees a new Debt Security or Debt Securities of authorized denominations for a like aggregate principal amount. In no event may Debt Securities be issued as, or exchanged for, bearer securities.

        Unless and until otherwise determined by the Partnership by resolution of the Board of Directors, the Debt Security Register shall be kept at the principal corporate trust office of the Trustee and, for this purpose, the Trustee shall be designated "Registrar."

        Debt Securities of any series (other than a Global Security, except as set forth below) may be exchanged for a like aggregate principal amount of Debt Securities of the same series of other authorized denominations. Subject to Section 2.15, Debt Securities to be exchanged shall be surrendered at the office or agency to be maintained by the Partnership as provided in Section 4.02, and the Partnership shall execute and the Trustee shall authenticate and deliver in exchange therefor the Debt Security or Debt Securities which the Holder making the exchange shall be entitled to receive.

        (b)   All Debt Securities presented or surrendered for registration of transfer, exchange or payment shall (if so required by the Partnership, the Trustee or the Registrar) be duly endorsed or be accompanied by a written instrument or instruments of transfer, in form satisfactory to the Partnership, the Trustee and the Registrar, duly executed by the Holder or his attorney duly authorized in writing.

        All Debt Securities issued in exchange for or upon transfer of Debt Securities shall be the valid obligations of the Partnership, evidencing the same debt, and entitled to the same benefits under this Indenture as the Debt Securities surrendered for such exchange or transfer.

        No service charge shall be made for any exchange or registration of transfer of Debt Securities (except as provided by Section 2.09), but the Partnership may require payment of a sum sufficient to cover any tax, fee, assessment or other governmental charge that may be imposed in relation thereto, other than those expressly provided in this Indenture to be made at the Partnership's own expense or without expense or without charge to the Holders.

        The Partnership shall not be required (i) to issue, register the transfer of or exchange any Debt Securities for a period of 15 days next preceding any mailing of notice of redemption of Debt Securities of such series or (ii) to register the transfer of or exchange any Debt Securities selected, called or being called for redemption.

        Prior to the due presentation for registration of transfer of any Debt Security, the Partnership, the Subsidiary Guarantors, the Trustee, any paying agent or any Registrar may deem and treat the Person

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in whose name a Debt Security is registered as the absolute owner of such Debt Security for the purpose of receiving payment of or on account of the principal of, and premium, if any, and (subject to Section 2.12) interest on, such Debt Security and for all other purposes whatsoever, whether or not such Debt Security is overdue, and none of the Partnership, the Subsidiary Guarantors, the Trustee, any paying agent or any Registrar shall be affected by notice to the contrary.

        None of the Partnership, the Subsidiary Guarantors, the Trustee, any agent of the Trustee, any paying agent or any Registrar will have any responsibility or liability for any aspect of the records relating to, or payments made on account of, beneficial ownership interests of a Global Security or for maintaining, supervising or reviewing any records relating to such beneficial ownership interests.

        Section 2.08 Temporary Debt Securities. Pending the preparation of definitive Debt Securities of any series, the Partnership may execute and the Trustee shall authenticate and deliver temporary Debt Securities (printed, lithographed, photocopied, typewritten or otherwise produced) of any authorized denomination, and substantially in the form of the definitive Debt Securities in lieu of which they are issued, in registered form with such omissions, insertions and variations as may be appropriate for temporary Debt Securities, all as may be determined by the Partnership with the concurrence of the Trustee. Temporary Debt Securities may contain such reference to any provisions of this Indenture as may be appropriate. Every temporary Debt Security shall be executed by the Partnership and be authenticated by the Trustee upon the same conditions and in substantially the same manner, and with like effect, as the definitive Debt Securities.

        If temporary Debt Securities of any series are issued, the Partnership will cause definitive Debt Securities of such series to be prepared without unreasonable delay. After the preparation of definitive Debt Securities of such series, the temporary Debt Securities of such series shall be exchangeable for definitive Debt Securities of such series upon surrender of the temporary Debt Securities of such series at the office or agency of the Partnership at a Place of Payment for such series, without charge to the Holder thereof, except as provided in Section 2.07 in connection with a transfer. Upon surrender for cancellation of any one or more temporary Debt Securities of any series, the Partnership shall execute and the Trustee shall authenticate and deliver in exchange therefor a like principal amount of definitive Debt Securities of the same series of authorized denominations and of like tenor. Until so exchanged, temporary Debt Securities of any series shall in all respects be entitled to the same benefits under this Indenture as definitive Debt Securities of such series.

        Upon any exchange of a portion of a temporary Global Security for a definitive Global Security or for the individual Debt Securities represented thereby pursuant to Section 2.07 or this Section 2.08, the temporary Global Security shall be endorsed by the Trustee to reflect the reduction of the principal amount evidenced thereby, whereupon the principal amount of such temporary Global Security shall be reduced for all purposes by the amount to be exchanged and endorsed.

        Section 2.09 Mutilated, Destroyed, Lost or Stolen Debt Securities. If (a) any mutilated Debt Security is surrendered to the Trustee at its corporate trust office or (b) the Partnership and the Trustee receive evidence to their satisfaction of the destruction, loss or theft of any Debt Security, and there is delivered to the Partnership and the Trustee such security or indemnity as may be required by them to save each of them and any paying agent harmless, and neither the Partnership nor the Trustee receives notice that such Debt Security has been acquired by a bona fide purchaser, then the Partnership shall execute and, upon a Partnership Order, the Trustee shall authenticate and deliver, in exchange for or in lieu of any such mutilated, destroyed, lost or stolen Debt Security, a new Debt Security of the same series of like tenor, form, terms and principal amount, bearing a number not contemporaneously Outstanding. Upon the issuance of any substituted Debt Security, the Partnership or the Trustee may require the payment of a sum sufficient to cover any tax, fee, assessment or other governmental charge that may be imposed in relation thereto and any other expenses connected therewith. In case any Debt Security which has matured or is about to mature or which has been called for redemption shall

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become mutilated or be destroyed, lost or stolen, the Partnership may, instead of issuing a substituted Debt Security, pay or authorize the payment of the same (without surrender thereof except in the case of a mutilated Debt Security) if the applicant for such payment shall furnish the Partnership and the Trustee with such security or indemnity as either may require to save it harmless from all risk, however remote, and, in case of destruction, loss or theft, evidence to the satisfaction of the Partnership and the Trustee of the destruction, loss or theft of such Debt Security and of the ownership thereof.

        Every substituted Debt Security of any series issued pursuant to the provisions of this Section 2.09 by virtue of the fact that any Debt Security is destroyed, lost or stolen shall constitute an original additional contractual obligation of the Partnership, whether or not the destroyed, lost or stolen Debt Security shall be found at any time, and shall be entitled to all the benefits of this Indenture equally and proportionately with any and all other Debt Securities of that series duly issued hereunder. All Debt Securities shall be held and owned upon the express condition that the foregoing provisions are exclusive with respect to the replacement or payment of mutilated, destroyed, lost or stolen Debt Securities, and shall preclude any and all other rights or remedies, notwithstanding any law or statute existing or hereafter enacted to the contrary with respect to the replacement or payment of negotiable instruments or other securities without their surrender.

        Section 2.10 Cancellation of Surrendered Debt Securities. All Debt Securities surrendered for payment, redemption, registration of transfer or exchange shall, if surrendered to the Partnership or any paying agent or a Registrar, be delivered to the Trustee for cancellation by it, or if surrendered to the Trustee, shall be canceled by it, and no Debt Securities shall be issued in lieu thereof except as expressly permitted by any of the provisions of this Indenture. All canceled Debt Securities held by the Trustee shall be destroyed (subject to the record retention requirements of the Exchange Act) and certification of their destruction delivered to the Partnership, unless otherwise directed. On request of the Partnership, the Trustee shall deliver to the Partnership canceled Debt Securities held by the Trustee. If the Partnership shall acquire any of the Debt Securities, however, such acquisition shall not operate as a redemption or satisfaction of the Debt represented thereby unless and until the same are delivered or surrendered to the Trustee for cancellation. The Partnership may not issue new Debt Securities to replace Debt Securities it has redeemed, paid or delivered to the Trustee for cancellation.

        Section 2.11 Provisions of the Indenture and Debt Securities for the Sole Benefit of the Parties and the Holders. Nothing in this Indenture or in the Debt Securities, expressed or implied, shall give or be construed to give to any Person, other than the parties hereto, the Holders or any Registrar or paying agent, any legal or equitable right, remedy or claim under or in respect of this Indenture, or under any covenant, condition or provision herein contained; all its covenants, conditions and provisions being for the sole benefit of the parties hereto, the Holders and any Registrar and paying agents.

        Section 2.12 Payment of Interest; Interest Rights Preserved.

        (a)   Interest on any Debt Security that is payable and is punctually paid or duly provided for on any interest payment date shall be paid to the Person in whose name such Debt Security is registered at the close of business on the regular record date for such interest notwithstanding the cancellation of such Debt Security upon any transfer or exchange subsequent to the regular record date. Payment of interest on Debt Securities shall be made at the corporate trust office of the Trustee (except as otherwise specified pursuant to Section 2.03), or at the option of the Partnership, by check mailed to the address of the Person entitled thereto as such address shall appear in the Debt Security Register or, if provided pursuant to Section 2.03 and in accordance with arrangements satisfactory to the Trustee, at the option of the Holder by wire transfer to an account designated by the Holder.

        (b)   Subject to the foregoing provisions of this Section 2.12 and Section 2.17, each Debt Security of a particular series delivered under this Indenture upon registration of transfer of or in exchange for or in lieu of any other Debt Security of the same series shall carry the rights to interest accrued and unpaid, and to accrue, which were carried by such other Debt Security.

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        Section 2.13 Securities Denominated in Dollars. Except as otherwise specified pursuant to Section 2.03 for Debt Securities of any series, payment of the principal of, and premium, if any, and interest on, Debt Securities of such series will be made in Dollars.

        Section 2.14 Wire Transfers. Notwithstanding any other provision to the contrary in this Indenture, the Partnership may make any payment of moneys required to be deposited with the Trustee on account of principal of, or premium, if any, or interest on, the Debt Securities (whether pursuant to optional or mandatory redemption payments, interest payments or otherwise) by wire transfer in immediately available funds to an account designated by the Trustee before 11:00 a.m., New York City time, on the date such moneys are to be paid to the Holders of the Debt Securities in accordance with the terms hereof.

        Section 2.15 Securities Issuable in the Form of a Global Security.

        (a)   If the Partnership shall establish pursuant to Sections 2.01 and 2.03 that the Debt Securities of a particular series are to be issued in whole or in part in the form of one or more Global Securities, then the Partnership shall execute and the Trustee or its agent shall, in accordance with Section 2.05, authenticate and deliver, such Global Security or Securities, which shall represent, and shall be denominated in an amount equal to the aggregate principal amount of, the Outstanding Debt Securities of such series to be represented by such Global Security or Securities, or such portion thereof as the Partnership shall specify in an Officers' Certificate, shall be registered in the name of the Depositary for such Global Security or Securities or its nominee, shall be delivered by the Trustee or its agent to the Depositary or pursuant to the Depositary's instruction and shall bear a legend substantially to the following effect:

        "UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY, A NEW YORK CORPORATION ("DTC"), NEW YORK, NEW YORK, TO THE COMPANY OR ITS AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY CERTIFICATE ISSUED IS REGISTERED IN THE NAME OF CEDE & CO. OR SUCH OTHER NAME AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC (AND ANY PAYMENT IS MADE TO CEDE & CO., OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL INASMUCH AS THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

        TRANSFERS OF THIS GLOBAL SECURITY SHALL BE LIMITED TO TRANSFERS IN WHOLE, BUT NOT IN PART, TO NOMINEES OF DTC OR TO A SUCCESSOR THEREOF OR SUCH SUCCESSOR'S NOMINEE AND TRANSFERS OF PORTIONS OF THIS GLOBAL SECURITY SHALL BE LIMITED TO TRANSFERS MADE IN ACCORDANCE WITH THE RESTRICTIONS SET FORTH IN THE INDENTURE REFERRED TO HEREIN."

or such other legend as may then be required by the Depositary for such Global Security or Securities.

        (b)   Notwithstanding any other provision of this Section 2.15 or of Section 2.07 to the contrary, and subject to the provisions of paragraph (c) below, unless the terms of a Global Security expressly permit such Global Security to be exchanged in whole or in part for definitive Debt Securities in registered form, a Global Security may be transferred, in whole but not in part and in the manner provided in Section 2.07, only by the Depositary to a nominee of the Depositary for such Global Security, or by a nominee of the Depositary to the Depositary or another nominee of the Depositary, or by the Depositary or a nominee of the Depositary to a successor Depositary for such Global Security selected or approved by the Partnership, or to a nominee of such successor Depositary.

        (c)   (i)  If at any time the Depositary for a Global Security or Securities notifies the Partnership that it is unwilling or unable to continue as Depositary for such Global Security or Securities or if at

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any time the Depositary for the Debt Securities for such series shall no longer be eligible or in good standing under the Exchange Act or other applicable statute, rule or regulation, the Partnership shall appoint a successor Depositary with respect to such Global Security or Securities. If a successor Depositary for such Global Security or Securities is not appointed by the Partnership within 90 days after the Partnership receives such notice or becomes aware of such ineligibility, the Partnership shall execute, and the Trustee or its agent, upon receipt of a Partnership Order for the authentication and delivery of such individual Debt Securities of such series in exchange for such Global Security or Securities, will authenticate and deliver, individual Debt Securities of such series of like tenor and terms in definitive form in an aggregate principal amount equal to the principal amount of the Global Security or Securities in exchange for such Global Security or Securities.

         (ii)  If an Event of Default occurs and the Depositary for a Global Security or Securities notifies the Trustee of its decision to require that the Debt Securities of any series or portion thereof issued or issuable in the form of one or more Global Securities shall no longer be represented by such Global Security or Securities, the Partnership shall appoint a successor Depositary with respect to such Global Security or Securities. In such event the Partnership will execute, and the Trustee, upon receipt of a Partnership Order for the authentication and delivery of individual Debt Securities of such series in exchange in whole or in part for such Global Security or Securities, will authenticate and deliver individual Debt Securities of such series of like tenor and terms in definitive form in an aggregate principal amount equal to the principal amount of such series or portion thereof in exchange for such Global Security or Securities.

        (iii)  If specified by the Partnership pursuant to Sections 2.01 and 2.03 with respect to Debt Securities issued or issuable in the form of a Global Security, the Depositary for such Global Security may surrender such Global Security in exchange in whole or in part for individual Debt Securities of such series of like tenor and terms in definitive form on such terms as are acceptable to the Partnership, the Trustee and such Depositary. Thereupon the Partnership shall execute, and the Trustee or its agent upon receipt of a Partnership Order for the authentication and delivery of definitive Debt Securities of such series shall authenticate and deliver, without service charge, to each Person specified by such Depositary a new Debt Security or Securities of the same series of like tenor and terms and of any authorized denomination as requested by such Person in aggregate principal amount equal to and in exchange for such Person's beneficial interest in the Global Security; and to such Depositary a new Global Security of like tenor and terms and in an authorized denomination equal to the difference, if any, between the principal amount of the surrendered Global Security and the aggregate principal amount of Debt Securities delivered to Holders thereof.

        (iv)  In any exchange provided for in any of the preceding three paragraphs, the Partnership will execute and the Trustee or its agent will authenticate and deliver individual Debt Securities. Upon the exchange of the entire principal amount of a Global Security for individual Debt Securities, such Global Security shall be canceled by the Trustee or its agent. Except as provided in the preceding paragraph, Debt Securities issued in exchange for a Global Security pursuant to this Section 2.15 shall be registered in such names and in such authorized denominations as the Depositary for such Global Security, pursuant to instructions from its direct or indirect participants or otherwise, shall instruct the Trustee or the Registrar. The Trustee or the Registrar shall deliver such Debt Securities to the Persons in whose names such Debt Securities are so registered.

         (v)  Payments in respect of the principal of and interest on any Debt Securities registered in the name of the Depositary or its nominee will be payable to the Depositary or such nominee in its capacity as the registered owner of such Global Security. The Partnership, any Subsidiary Guarantors and the Trustee may treat the Person in whose name the Debt Securities, including the Global Security, are registered as the owner thereof for the purpose of receiving such payments and for any and all other purposes whatsoever. None of the Partnership, any Subsidiary

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Guarantors, the Trustee, any Registrar, the paying agent or any agent of the Partnership, any Subsidiary Guarantors or the Trustee will have any responsibility or liability for any aspect of the records relating to or payments made on account of the beneficial ownership interests of the Global Security by the Depositary or its nominee or any of the Depositary's direct or indirect participants, or for maintaining, supervising or reviewing any records of the Depositary, its nominee or any of its direct or indirect participants relating to the beneficial ownership interests of the Global Security, the payments to the beneficial owners of the Global Security of amounts paid to the Depositary or its nominee, or any other matter relating to the actions and practices of the Depositary, its nominee or any of its direct or indirect participants. None of the Partnership, any Subsidiary Guarantors, the Trustee or any such agent will be liable for any delay by the Depositary, its nominee, or any of its direct or indirect participants in identifying the beneficial owners of the Debt Securities, and the Partnership, any Subsidiary Guarantors and the Trustee may conclusively rely on, and will be protected in relying on, instructions from the Depositary or its nominee for all purposes (including with respect to the registration and delivery, and the respective principal amounts, of the Debt Securities to be issued).

        Section 2.16 Medium Term Securities. Notwithstanding any contrary provision herein, if all Debt Securities of a series are not to be originally issued at one time, it shall not be necessary for the Partnership to deliver to the Trustee an Officers' Certificate, resolutions of the Board of Directors, supplemental Indenture, Opinion of Counsel or written order or any other document otherwise required pursuant to Section 2.01, 2.03, 2.05 or 13.05 at or prior to the time of authentication of each Debt Security of such series if such documents are delivered to the Trustee or its agent at or prior to the authentication upon original issuance of the first such Debt Security of such series to be issued; provided, that any subsequent request by the Partnership to the Trustee to authenticate Debt Securities of such series upon original issuance shall constitute a representation and warranty by the Partnership that, as of the date of such request, the statements made in the Officers' Certificate delivered pursuant to Section 2.05 or 13.05 shall be true and correct as if made on such date and that the Opinion of Counsel delivered at or prior to such time of authentication of an original issuance of Debt Securities shall specifically state that it shall relate to all subsequent issuances of Debt Securities of such series that are identical to the Debt Securities issued in the first issuance of Debt Securities of such series.

        A Partnership Order delivered by the Partnership to the Trustee in the circumstances set forth in the preceding paragraph, may provide that Debt Securities which are the subject thereof will be authenticated and delivered by the Trustee or its agent on original issue from time to time upon the telephonic or written order of Persons designated in such written order (any such telephonic instructions to be promptly confirmed in writing by such Person) and that such Persons are authorized to determine, consistent with the Officers' Certificate, supplemental Indenture or resolution of the Board of Directors relating to such written order, such terms and conditions of such Debt Securities as are specified in such Officers' Certificate, supplemental Indenture or such resolution.

        Section 2.17 Defaulted Interest. Any interest on any Debt Security of a particular series which is payable, but is not punctually paid or duly provided for, on the dates and in the manner provided in the Debt Securities of such series and in this Indenture (herein called "Defaulted Interest") shall forthwith cease to be payable to the Holder thereof on the relevant record date by virtue of having been such Holder, and such Defaulted Interest may be paid by the Partnership, at its election in each case, as provided in clause (i) or (ii) below:

          (i)  The Partnership may elect to make payment of any Defaulted Interest to the Persons in whose names the Debt Securities of such series are registered at the close of business on a special record date for the payment of such Defaulted Interest, which shall be fixed in the following manner. The Partnership shall notify the Trustee in writing of the amount of Defaulted Interest proposed to be paid on each such Debt Security of such series and the date of the proposed payment, and at the same time the Partnership shall deposit with the Trustee an amount of money

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equal to the aggregate amount proposed to be paid in respect of such Defaulted Interest or shall make arrangements satisfactory to the Trustee for such deposit prior to the date of the proposed payment, such money when deposited to be held in trust for the benefit of the Persons entitled to such Defaulted Interest as in this clause provided. Thereupon the Trustee shall fix a special record date for the payment of such Defaulted Interest which shall be not more than 15 days and not less than 10 days prior to the date of the proposed payment and not less than 10 days after the receipt by the Trustee of the notice of the proposed payment. The Trustee shall promptly notify the Partnership of such special record date and, in the name and at the expense of the Partnership, shall cause notice of the proposed payment of such Defaulted Interest and the special record date therefor to be mailed, first class postage pre-paid, to each Holder thereof at its address as it appears in the Debt Security Register, not less than 10 days prior to such special record date. Notice of the proposed payment of such Defaulted Interest and the special record date therefor having been so mailed, such Defaulted Interest shall be paid to the Persons in whose names the Debt Securities of such series are registered at the close of business on such special record date.

         (ii)  The Partnership may make payment of any Defaulted Interest on the Debt Securities of such series in any other lawful manner not inconsistent with the requirements of any securities exchange on which the Debt Securities of such series may be listed, and upon such notice as may be required by such exchange, if, after notice given by the Partnership to the Trustee of the proposed payment pursuant to this clause, such manner of payment shall be deemed practicable by the Trustee.

        Section 2.18 CUSIP Numbers. The Partnership in issuing the Debt Securities may use "CUSIP" numbers (if then generally in use), and, if so, the Trustee shall use "CUSIP" numbers in notices of redemption as a convenience to Holders; provided that any such notice may state that no representation is made as to the accuracy of such numbers either as printed on the Debt Securities or as contained in any notice of a redemption and that reliance may be placed only on the other identification numbers printed on the Debt Securities, and any such redemption shall not be affected by any defect in or omission of such numbers. The Partnership will promptly notify the Trustee in writing of any change in the "CUSIP" numbers.

ARTICLE III

REDEMPTION OF DEBT SECURITIES

        Section 3.01 Applicability of Article. The provisions of this Article shall be applicable to the Debt Securities of any series which are redeemable before their Stated Maturity except as otherwise specified as contemplated by Section 2.03 for Debt Securities of such series.

        Section 3.02 Notice of Redemption; Selection of Debt Securities. In case the Partnership shall desire to exercise the right to redeem all or, as the case may be, any part of the Debt Securities of any series in accordance with their terms, by resolution of the Board of Directors or a supplemental Indenture, the Partnership shall fix a date for redemption and shall give notice of such redemption at least 30 and not more than 60 days prior to the date fixed for redemption to the Holders of Debt Securities of such series so to be redeemed as a whole or in part, in the manner provided in Section 13.03. The notice if given in the manner herein provided shall be conclusively presumed to have been duly given, whether or not the Holder receives such notice. In any case, failure to give such notice or any defect in the notice to the Holder of any Debt Security of a series designated for redemption as a whole or in part shall not affect the validity of the proceedings for the redemption of any other Debt Security of such series.

        Each such notice of redemption shall specify (i) the date fixed for redemption, (ii) the redemption price at which Debt Securities of such series are to be redeemed (or the method of calculating such redemption price), (iii) the Place or Places of Payment that payment will be made upon presentation

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and surrender of such Debt Securities, (iv) that any interest accrued to the date fixed for redemption will be paid as specified in said notice, (v) that the redemption is for a sinking fund payment (if applicable), (vi) that, unless otherwise specified in such notice, if the Partnership defaults in making such redemption payment, the paying agent is prohibited from making such payment pursuant to the terms of this Indenture, (vii) that on and after said date any interest thereon or on the portions thereof to be redeemed will cease to accrue, (viii) that in the case of Original Issue Discount Securities original issue discount accrued after the date fixed for redemption will cease to accrue, (ix) the terms of the Debt Securities of that series pursuant to which the Debt Securities of that series are being redeemed and (x) that no representation is made as to the correctness or accuracy of the CUSIP number, if any, listed in such notice or printed on the Debt Securities of that series. If less than all the Debt Securities of a series are to be redeemed the notice of redemption shall specify the certificate numbers of any Debt Securities of that series to be redeemed that are not in global form. In case any Debt Security of a series is to be redeemed in part only, the notice of redemption shall state the portion of the principal amount thereof to be redeemed and shall state that on and after the date fixed for redemption, upon surrender of such Debt Security, a new Debt Security or Debt Securities of that series in principal amount equal to the unredeemed portion thereof, will be issued.

        At least five days before the giving of any notice of redemption, unless the Trustee consents to a shorter period, the Partnership shall give written notice to the Trustee of the Redemption Date, the principal amount of Debt Securities to be redeemed and the series and terms of the Debt Securities pursuant to which such redemption will occur. Such notice shall be accompanied by an Officers' Certificate and an Opinion of Counsel from the Partnership to the effect that such redemption will comply with the conditions herein, and such notice may be revoked at any time prior to the giving of a notice of redemption to the Holders pursuant to this Section 3.02. If fewer than all the Debt Securities of a series are to be redeemed, the record date relating to such redemption shall be selected by the Partnership and given in writing to the Trustee, which record date shall be not less than three days after the date of notice to the Trustee.

        By 11 a.m., New York City time, on the Redemption Date for any Debt Securities, the Partnership shall deposit with the Trustee or with a paying agent (or, if the Partnership is acting as its own paying agent, segregate and hold in trust) an amount of money in Dollars (except as provided pursuant to Section 2.03) sufficient to pay the redemption price of such Debt Securities or any portions thereof that are to be redeemed on that date, together with any interest accrued to the Redemption Date.

        If less than all the Debt Securities of like tenor and terms of a series are to be redeemed (other than pursuant to mandatory sinking fund redemptions), the Trustee shall select, on a pro rata basis, by lot or by such other method as in its sole discretion it shall deem appropriate and fair, the Debt Securities of that series or portions thereof (in multiples of $1,000) to be redeemed. In any case where more than one Debt Security of such series is registered in the same name, the Trustee in its discretion may treat the aggregate principal amount so registered as if it were represented by one Debt Security of such series. The Trustee shall promptly notify the Partnership in writing of the Debt Securities selected for redemption and, in the case of any Debt Securities selected for partial redemption, the principal amount thereof to be redeemed. If any Debt Security called for redemption shall not be so paid upon surrender thereof on such Redemption Date, the principal, premium, if any, and interest shall bear interest until paid from the Redemption Date at the rate borne by the Debt Securities of that series. If less than all the Debt Securities of unlike tenor and terms of a series are to be redeemed, the particular Debt Securities to be redeemed shall be selected by the Partnership. Provisions of this Indenture that apply to Debt Securities called for redemption also apply to portions of Debt Securities called for redemption.

        Section 3.03 Payment of Debt Securities Called for Redemption. If notice of redemption has been given as provided in Section 3.02, the Debt Securities or portions of Debt Securities of the series with respect to which such notice has been given shall become due and payable on the date and at the Place

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or Places of Payment stated in such notice at the applicable redemption price, together with any interest accrued to the date fixed for redemption, and on and after said date (unless the Partnership shall default in the payment of such Debt Securities at the applicable redemption price, together with any interest accrued to said date) any interest on the Debt Securities or portions of Debt Securities of any series so called for redemption shall cease to accrue, and any original issue discount in the case of Original Issue Discount Securities shall cease to accrue. On presentation and surrender of such Debt Securities at the Place or Places of Payment in said notice specified, the said Debt Securities or the specified portions thereof shall be paid and redeemed by the Partnership at the applicable redemption price, together with any interest accrued thereon to the date fixed for redemption.

        Any Debt Security that is to be redeemed only in part shall be surrendered at the Place of Payment with, if the Partnership, the Registrar or the Trustee so requires, due endorsement by, or a written instrument of transfer in form satisfactory to the Partnership, the Registrar and the Trustee duly executed by, the Holder thereof or his attorney duly authorized in writing, and the Partnership shall execute, and the Trustee shall authenticate and deliver to the Holder of such Debt Security without service charge, a new Debt Security or Debt Securities of the same series, of like tenor and form, of any authorized denomination as requested by such Holder in aggregate principal amount equal to and in exchange for the unredeemed portion of the principal of the Debt Security so surrendered; except that if a Global Security is so surrendered, the Partnership shall execute, and the Trustee shall authenticate and deliver to the Depositary for such Global Security, without service charge, a new Global Security in a denomination equal to and in exchange for the unredeemed portion of the principal of the Global Security so surrendered. In the case of a Debt Security providing appropriate space for such notation, at the option of the Holder thereof, the Trustee, in lieu of delivering a new Debt Security or Debt Securities as aforesaid, may make a notation on such Debt Security of the payment of the redeemed portion thereof.

        Section 3.04 Mandatory and Optional Sinking Funds. The minimum amount of any sinking fund payment provided for by the terms of Debt Securities of any series, resolution of the Board of Directors or a supplemental Indenture is herein referred to as a "mandatory sinking fund payment," and any payment in excess of such minimum amount provided for by the terms of Debt Securities of any series, resolution of the Board of Directors or a supplemental Indenture is herein referred to as an "optional sinking fund payment."

        In lieu of making all or any part of any mandatory sinking fund payment with respect to any Debt Securities of a series in cash, the Partnership may at its option (a) deliver to the Trustee Debt Securities of that series theretofore purchased or otherwise acquired by the Partnership or (b) receive credit for the principal amount of Debt Securities of that series which have been redeemed either at the election of the Partnership pursuant to the terms of such Debt Securities or through the application of permitted optional sinking fund payments pursuant to the terms of such Debt Securities, resolution or supplemental Indenture; provided, that such Debt Securities have not been previously so credited. Such Debt Securities shall be received and credited for such purpose by the Trustee at the redemption price specified in such Debt Securities, resolution or supplemental Indenture for redemption through operation of the sinking fund and the amount of such mandatory sinking fund payment shall be reduced accordingly.

        Section 3.05 Redemption of Debt Securities for Sinking Fund. Not less than 60 days prior to each sinking fund payment date for any series of Debt Securities, the Partnership will deliver to the Trustee an Officers' Certificate specifying the amount of the next ensuing sinking fund payment for that series pursuant to the terms of that series, any resolution or supplemental Indenture, the portion thereof, if any, which is to be satisfied by payment of cash and the portion thereof, if any, which is to be satisfied by delivering and crediting Debt Securities of that series pursuant to this Section 3.05 (which Debt Securities, if not previously redeemed, will accompany such certificate) and whether the Partnership intends to exercise its right to make any permitted optional sinking fund payment with respect to such

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series. Such certificate shall also state that no Event of Default has occurred and is continuing with respect to such series. Such certificate shall be irrevocable and upon its delivery the Partnership shall be obligated to make the cash payment or payments therein referred to, if any, by 11 a.m., New York City time, on the next succeeding sinking fund payment date. Failure of the Partnership to deliver such certificate (or to deliver the Debt Securities specified in this paragraph) shall not constitute a Default, but such failure shall require that the sinking fund payment due on the next succeeding sinking fund payment date for that series shall be paid entirely in cash and shall be sufficient to redeem the principal amount of such Debt Securities subject to a mandatory sinking fund payment without the option to deliver or credit Debt Securities as provided in this Section 3.05 and without the right to make any optional sinking fund payment, if any, with respect to such series.

        Any sinking fund payment or payments (mandatory or optional) made in cash plus any unused balance of any preceding sinking fund payments made in cash which shall equal or exceed $100,000 (or a lesser sum if the Partnership shall so request) with respect to the Debt Securities of any particular series shall be applied by the Trustee on the sinking fund payment date on which such payment is made (or, if such payment is made before a sinking fund payment date, on the sinking fund payment date following the date of such payment) to the redemption of such Debt Securities at the redemption price specified in such Debt Securities, resolution or supplemental Indenture for operation of the sinking fund together with any accrued interest to the date fixed for redemption. Any sinking fund moneys not so applied or allocated by the Trustee to the redemption of Debt Securities shall be added to the next cash sinking fund payment received by the Trustee for such series and, together with such payment, shall be applied in accordance with the provisions of this Section 3.05. Any and all sinking fund moneys with respect to the Debt Securities of any particular series held by the Trustee on the last sinking fund payment date with respect to Debt Securities of such series and not held for the payment or redemption of particular Debt Securities shall be applied by the Trustee, together with other moneys, if necessary, to be deposited sufficient for the purpose, to the payment of the principal of the Debt Securities of that series at its Stated Maturity.

        The Trustee shall select the Debt Securities to be redeemed upon such sinking fund payment date in the manner specified in the last paragraph of Section 3.02 and the Partnership shall cause notice of the redemption thereof to be given in the manner provided in Section 3.02 except that the notice of redemption shall also state that the Debt Securities are being redeemed by operation of the sinking fund. Such notice having been duly given, the redemption of such Debt Securities shall be made upon the terms and in the manner stated in Section 3.03.

        The Trustee shall not redeem any Debt Securities of a series with sinking fund moneys or mail any notice of redemption of such Debt Securities by operation of the sinking fund for such series during the continuance of a Default in payment of interest on such Debt Securities or of any Event of Default (other than an Event of Default occurring as a consequence of this paragraph) with respect to such Debt Securities, except that if the notice of redemption of any such Debt Securities shall theretofore have been mailed in accordance with the provisions hereof, the Trustee shall redeem such Debt Securities if cash sufficient for that purpose shall be deposited with the Trustee for that purpose in accordance with the terms of this Article III. Except as aforesaid, any moneys in the sinking fund for such series at the time when any such Default or Event of Default shall occur and any moneys thereafter paid into such sinking fund shall, during the continuance of such Default or Event of Default, be held as security for the payment of such Debt Securities; provided, however, that in case such Default or Event of Default shall have been cured or waived as provided herein, such moneys shall thereafter be applied on the next sinking fund payment date for such Debt Securities on which such moneys may be applied pursuant to the provisions of this Section 3.05.

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ARTICLE IV

PARTICULAR COVENANTS OF THE COMPANY

        Section 4.01 Payment of Principal of, and Premium, If Any, and Interest on, Debt Securities. The Partnership, for the benefit of each series of Debt Securities, will duly and punctually pay or cause to be paid the principal of, and premium, if any, and interest on, each of the Debt Securities at the place, at the respective times and in the manner provided herein or in the Debt Securities. Each installment of interest on any Debt Securities not in global form may at the Partnership's option be paid by mailing checks for such interest payable to the Person entitled thereto pursuant to Section 2.07(a) to the address of such Person as it appears on the Debt Security Register.

        Principal of and premium and interest on Debt Securities of any series shall be considered paid on the date due if, by 11 a.m., New York City time, on such date the Trustee or any paying agent holds in accordance with this Indenture money sufficient to pay all principal, premium and interest then due.

        The Partnership shall pay interest on overdue principal or premium, if any, at the rate specified therefor in the Debt Securities, and it shall pay interest on overdue installments of interest at the same rate to the extent lawful.

        Section 4.02 Maintenance of Offices or Agencies for Registration of Transfer, Exchange and Payment of Debt Securities. The Partnership will maintain in each Place of Payment for any series of Debt Securities an office or agency where Debt Securities of such series may be presented or surrendered for payment, and it shall also maintain (in or outside such Place of Payment) an office or agency where Debt Securities of such series may be surrendered for transfer or exchange and where notices and demands to or upon the Partnership in respect of the Debt Securities of such series and this Indenture may be served. The Partnership will give prompt written notice to the Trustee of the location, and any change in the location, of such office or agency. If at any time the Partnership shall fail to maintain any such required office or agency or shall fail to furnish the Trustee with the address thereof, such presentations, surrenders, notices and demands may be made or served at the office of the Trustee where its corporate trust business is principally administered in the United States, and the Partnership hereby appoints the Trustee as its agent to receive all presentations, surrenders, notices and demands.

        The Partnership may also from time to time designate different or additional offices or agencies to be maintained for such purposes (in or outside of such Place of Payment), and may from time to time rescind any such designation; provided, however, that no such designation or rescission shall in any manner relieve the Partnership of its obligations described in the preceding paragraph. The Partnership will give prompt written notice to the Trustee of any such additional designation or rescission of designation and any change in the location of any such different or additional office or agency.

        Section 4.03 Appointment to Fill a Vacancy in the Office of Trustee. The Partnership, whenever necessary to avoid or fill a vacancy in the office of Trustee, will appoint, in the manner provided in Section 7.08, a Trustee, so that there shall at all times be a Trustee hereunder with respect to each series of Debt Securities.

        Section 4.04 Duties of Paying Agents, etc.

        (a)   The Partnership shall cause each paying agent, if any, other than the Trustee, to execute and deliver to the Trustee an instrument in which such agent shall agree with the Trustee, subject to the provisions of this Section 4.04,

          (i)  that it will hold all sums held by it as such agent for the payment of the principal of, and premium, if any, or interest on, the Debt Securities of any series (whether such sums have been paid to it by the Partnership or by any other obligor on the Debt Securities of such series) in trust for the benefit of the Holders of the Debt Securities of such series;

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         (ii)  that it will give the Trustee notice of any failure by the Partnership (or by any other obligor on the Debt Securities of such series) to make any payment of the principal of, and premium, if any, or interest on, the Debt Securities of such series when the same shall be due and payable; and

        (iii)  that it will at any time during the continuance of an Event of Default, upon the written request of the Trustee, forthwith pay to the Trustee all sums so held by it as such agent.

        (b)   If the Partnership shall act as its own paying agent, it will, on or before each due date of the principal of, and premium, if any, or interest on, the Debt Securities of any series, set aside, segregate and hold in trust for the benefit of the Holders of the Debt Securities of such series a sum sufficient to pay such principal, premium, if any, or interest so becoming due. The Partnership will promptly notify the Trustee of any failure by the Partnership to take such action or the failure by any other obligor on such Debt Securities to make any payment of the principal of, and premium, if any, or interest on, such Debt Securities when the same shall be due and payable.

        (c)   Anything in this Section 4.04 to the contrary notwithstanding, the Partnership may, at any time, for the purpose of obtaining a satisfaction and discharge of this Indenture, or for any other reason, pay or cause to be paid to the Trustee all sums held in trust by it or any paying agent, as required by this Section 4.04, such sums to be held by the Trustee upon the same trusts as those upon which such sums were held by the Partnership or such paying agent.

        (d)   Whenever the Partnership shall have one or more paying agents with respect to any series of Debt Securities, it will, prior to each due date of the principal of, and premium, if any, or interest on, any Debt Securities of such series, deposit with any such paying agent a sum sufficient to pay the principal, premium or interest so becoming due, such sum to be held in trust for the benefit of the Persons entitled thereto, and (unless any such paying agent is the Trustee) the Partnership will promptly notify the Trustee of its action or failure so to act.

        (e)   Anything in this Section 4.04 to the contrary notwithstanding, the agreement to hold sums in trust as provided in this Section 4.04 is subject to the provisions of Section 11.05.

        Section 4.05 SEC Reports; Financial Statements.

        (a)   The Partnership shall, so long as any of the Debt Securities are Outstanding, file with the Trustee, within 30 days after it files the same with the SEC, copies of the annual reports and the information, documents and other reports (or copies of such portions of any of the foregoing as the SEC may by rules and regulations prescribe) that the Partnership is required to file with the SEC pursuant to Section 13 or 15(d) of the Exchange Act. If the Partnership is not subject to the requirements of such Section 13 or 15(d), the Partnership shall file with the Trustee, within 30 days after it would have been required to file the same with the SEC, financial statements, including any notes thereto (and with respect to annual reports, an auditors' report by a firm of established national reputation), and a "Management's Discussion and Analysis of Financial Condition and Results of Operations," both comparable to that which the Partnership would have been required to include in such annual reports, information, documents or other reports if the Partnership had been subject to the requirements of such Section 13 or 15(d). The Partnership shall also comply with the provisions of TIA Section 314(a).

        (b)   The Partnership shall provide the Trustee with a sufficient number of copies of all reports and other documents and information that the Trustee may be required to deliver to Holders under this Section.

        (c)   The Partnership shall, so long as any of the Debt Securities are Outstanding, deliver to the Trustee, within 30 days of any Officer of the Partnership becoming aware of the occurrence of any

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Event of Default, an Officers' Certificate specifying such Event of Default and what action the Partnership is taking or proposes to take with respect thereto.

        Section 4.06 Compliance Certificate.

        (a)   The Partnership and any Subsidiary Guarantor shall, so long as any of the Debt Securities are Outstanding, deliver to the Trustee, within 120 days after the end of each fiscal year of the Partnership, an Officers' Certificate stating that a review of the activities of the Partnership and its Subsidiaries during the preceding fiscal year has been made under the supervision of the signing Officers of the Partnership with a view to determining whether each of the Partnership and any Subsidiary Guarantor has kept, observed, performed and fulfilled its obligations under this Indenture, and further stating, as to each such Officer signing such certificate, that to the best of his knowledge each of the Partnership and any Subsidiary Guarantor has kept, observed, performed and fulfilled each and every covenant contained in this Indenture and is not in default in the performance or observance of any of the terms, provisions and conditions hereof, without regard to any grace period or requirement of notice required by this Indenture (or, if a Default or Event of Default shall have occurred, describing all such Defaults or Events of Default of which such Officer may have knowledge and what action the Partnership or any Subsidiary Guarantor is taking or proposes to take with respect thereto).

        (b)   The Partnership shall, so long as any of the Debt Securities are Outstanding, deliver to the Trustee within 30 days after the occurrence of any Default or Event of Default under this Indenture, an Officers' Certificate specifying such Default or Event of Default, the status thereof and what action the Partnership is taking or proposes to take with respect thereto.

        Section 4.07 Further Instruments and Acts. The Partnership will, upon request of the Trustee, execute and deliver such further instruments and do such further acts as may reasonably be necessary or proper to carry out more effectually the purposes of this Indenture.

        Section 4.08 Existence. Except as permitted by Article X hereof, the Partnership shall do or cause to be done all things necessary to preserve and keep in full force and effect its existence and all rights (charter and statutory) and franchises of the Partnership, provided that the Partnership shall not be required to preserve any such right or franchise, if the Board of Directors shall determine that the preservation thereof is no longer desirable in the conduct of the business of the Partnership.

        Section 4.09 Maintenance of Properties. The Partnership shall cause all properties owned by the Partnership or any of its Subsidiaries or used or held for use in the conduct of its business or the business of any such Subsidiary to be maintained and kept in good condition, repair and working order (reasonable wear and tear excepted) and supplied with all necessary equipment and will cause to be made all necessary repairs, renewals, replacements, betterments and improvements thereof, all as in the judgment of the Partnership may be necessary so that the business carried on in connection therewith may be properly and advantageously conducted at all times; provided that nothing in this Section shall prevent the Partnership from discontinuing the operation or maintenance of any of such properties if such discontinuance is, in the judgment of the Partnership, desirable in the conduct of its business or the business of any such Subsidiary and not disadvantageous in any material respect to the Holders.

        Section 4.10 Payment of Taxes and Other Claims. The Partnership shall pay or discharge or cause to be paid or discharged, before the same shall become delinquent, (i) all taxes, assessments and governmental charges levied or imposed upon the Partnership or any of its Subsidiaries or upon the income, profits or property of the Partnership or any of its Subsidiaries, and (ii) all lawful claims for labor, materials and supplies which, if unpaid, might by law become a Lien upon the property of the Partnership or any of its Subsidiaries; provided that the Partnership shall not be required to pay or discharge or cause to be paid or discharged any such tax, assessment, charge or claim whose amount, applicability or validity is being contested in good faith by appropriate proceedings.

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        Section 4.11 Waiver of Certain Covenants. The Partnership and the Subsidiary Guarantors may, with respect to the Debt Securities of any series, omit in any particular instance to comply with any covenant set forth in this Article IV (except Sections 4.01 through 4.08) or made applicable to such Debt Securities pursuant to Section 2.03, if, before or after the time for such compliance, the Holders of at least a majority in principal amount of the Outstanding Debt Securities of each series affected, waive such compliance in such instance with such covenant, but no such waiver shall extend to or affect such covenant except to the extent so expressly waived, and, until such waiver shall become effective, the obligations of the Partnership and the Subsidiary Guarantors and the duties of the Trustee in respect of any such covenant shall remain in full force and effect.

ARTICLE V

HOLDERS' LISTS AND REPORTS BY THE TRUSTEE

        Section 5.01 Partnership to Furnish Trustee Information as to Names and Addresses of Holders; Preservation of Information. The Partnership covenants and agrees that it will furnish or cause to be furnished to the Trustee with respect to the Debt Securities of each series:

        (a)   not more than 10 days after each record date with respect to the payment of interest, if any, a list, in such form as the Trustee may reasonably require, of the names and addresses of the Holders as of such record date, and

        (b)   at such other times as the Trustee may request in writing, within 30 days after the receipt by the Partnership of any such request, a list of similar form and contents as of a date not more than 15 days prior to the time such list is furnished;

provided, however, that so long as the Trustee shall be the Registrar, such lists shall not be required to be furnished.

        The Trustee shall preserve, in as current a form as is reasonably practicable, all information as to the names and addresses of the Holders (i) contained in the most recent list furnished to it as provided in this Section 5.01 or (ii) received by it in the capacity of paying agent or Registrar (if so acting) hereunder.

        The Trustee may destroy any list furnished to it as provided in this Section 5.01 upon receipt of a new list so furnished.

        Section 5.02 Communications to Holders. Holders may communicate pursuant to Section 312(b) of the TIA with other Holders with respect to their rights under this Indenture or the Debt Securities. The Partnership, the Trustee, the Registrar and anyone else shall have the protection of Section 312(c) of the TIA.

        Section 5.03 Reports by Trustee. Within 60 days after each January 31, beginning with the first January 31 following the date of this Indenture, and in any event on or before April 1 in each year, the Trustee shall mail to Holders a brief report dated as of such January 31 that complies with TIA Section 313(a); provided, however, that if no event described in TIA Section 313(a) has occurred within the twelve months preceding the reporting date, no report need be transmitted. The Trustee also shall comply with TIA Section 313(b).

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        Reports pursuant to this Section 5.03 shall be transmitted by mail:

        (a)   to all Holders, as the names and addresses of such Holders appear in the Debt Security Register; and

        (b)   except in the cases of reports under Section 313(b)(2) of the TIA, to each Holder of a Debt Security of any series whose name and address appear in the information preserved at the time by the Trustee in accordance with Section 5.01.

        A copy of each report at the time of its mailing to Holders shall be filed with the Securities and Exchange Commission and each stock exchange (if any) on which the Debt Securities of any series are listed. The Partnership agrees to notify promptly the Trustee whenever the Debt Securities of any series become listed on any stock exchange and of any delisting thereof.

        Section 5.04 Record Dates for Action by Holders. If the Partnership shall solicit from the Holders of Debt Securities of any series any action (including the making of any demand or request, the giving of any direction, notice, consent or waiver or the taking of any other action), the Partnership may, at its option, by resolution of the Board of Directors, fix in advance a record date for the determination of Holders of Debt Securities entitled to take such action, but the Partnership shall have no obligation to do so. Any such record date shall be fixed at the Partnership's discretion. If such a record date is fixed, such action may be sought or given before or after the record date, but only the Holders of Debt Securities of record at the close of business on such record date shall be deemed to be Holders of Debt Securities for the purpose of determining whether Holders of the requisite proportion of Debt Securities of such series Outstanding have authorized or agreed or consented to such action, and for that purpose the Debt Securities of such series Outstanding shall be computed as of such record date.

ARTICLE VI

REMEDIES OF THE TRUSTEE AND HOLDERS IN EVENT OF DEFAULT

        Section 6.01 Events of Default. If any one or more of the following shall have occurred and be continuing with respect to Debt Securities of any series (each of the following, an "Event of Default"):

        (a)   default in the payment of any installment of interest upon any Debt Securities of that series as and when the same shall become due and payable, and continuance of such default for a period of 30 days; or

        (b)   default in the payment of the principal of or premium, if any, on any Debt Securities of that series as and when the same shall become due and payable, whether at Stated Maturity, upon redemption, by declaration, upon required repurchase or otherwise; or

        (c)   default in the payment of any sinking fund payment with respect to any Debt Securities of that series as and when the same shall become due and payable; or

        (d)   failure on the part of the Partnership, or if any series of Debt Securities Outstanding under this Indenture is entitled to the benefits of the Guarantee, any of the Subsidiary Guarantors, duly to observe or perform any other of the covenants or agreements on the part of the Partnership, or if applicable, any of the Subsidiary Guarantors, in the Debt Securities of that series, in any resolution of the Board of Directors authorizing the issuance of that series of Debt Securities, in this Indenture with respect to such series or in any supplemental Indenture with respect to such series (other than a covenant a default in the performance of which is elsewhere in this Section specifically dealt with), continuing for a period of 60 days after the date on which written notice specifying such failure and requiring the Partnership, or if applicable, the Subsidiary Guarantors, to remedy the same shall have been given to the Partnership, or if applicable, the Subsidiary Guarantors, by the Trustee or to the Partnership, or if applicable, the Subsidiary Guarantors, and the Trustee by the Holders of at least 25% in aggregate principal amount of the Debt Securities of that series at the time Outstanding; or

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        (e)   the Partnership, or if any series of Debt Securities Outstanding under this Indenture is entitled to the benefits of the Guarantee, any of the Subsidiary Guarantors, pursuant to or within the meaning of any Bankruptcy Law,

          (i)  commences a voluntary case,

         (ii)  consents to the entry of an order for relief against it in an involuntary case,

        (iii)  consents to the appointment of a Custodian of it or for all or substantially all of its property; or

        (iv)  makes a general assignment for the benefit of its creditors;

        (f)    a court of competent jurisdiction enters an order or decree under any Bankruptcy Law that:

          (i)  is for relief against the Partnership, or if any series of Debt Securities Outstanding under this Indenture is entitled to the benefits of the Guarantee, any of the Subsidiary Guarantors, as debtor in an involuntary case,

         (ii)  appoints a Custodian of the Partnership, or if any series of Debt Securities Outstanding under this Indenture is entitled to the benefits of the Guarantee, any of the Subsidiary Guarantors, or a Custodian for all or substantially all of the property of the Partnership, or if applicable, any of the Subsidiary Guarantors, or

        (iii)  orders the liquidation of the Partnership, or if any series of Debt Securities Outstanding under this Indenture is entitled to the benefits of the Guarantee, any of the Subsidiary Guarantors,

and the order or decree remains unstayed and in effect for 60 days;

        (g)   if any series of Debt Securities Outstanding under this Indenture is entitled to the benefits of the Guarantee, the Guarantee of any of the Subsidiary Guarantors ceases to be in full force and effect with respect to Debt Securities of that series (except as otherwise provided in this Indenture) or is declared null and void in a judicial proceeding or any of the Subsidiary Guarantors denies or disaffirms its obligations under this Indenture or such Guarantee; or

        (h)   any other Event of Default provided with respect to Debt Securities of that series;

then and in each and every case that an Event of Default described in clause (a), (b), (c), (d), (g), or (h) with respect to Debt Securities of that series at the time Outstanding occurs with respect to the Partnership and is continuing, unless the principal of, premium, if any, and accrued and unpaid interest on all the Debt Securities of that series shall have already become due and payable, either the Trustee or the Holders of not less than 25% in aggregate principal amount of the Debt Securities of that series then Outstanding hereunder, by notice in writing to the Partnership (and to the Trustee if given by Holders), may declare the principal of (or, if the Debt Securities of that series are Original Issue Discount Debt Securities, such portion of the principal amount as may be specified in the terms of that series), premium, if any, and interest on all the Debt Securities of that series to be due and payable immediately, and upon any such declaration the same shall become and shall be immediately due and payable, anything in this Indenture or in the Debt Securities of that series contained to the contrary notwithstanding. If an Event of Default described in clause (e) or (f) occurs with respect to the Partnership, then and in each and every such case, unless the principal of and accrued and unpaid interest on all the Debt Securities shall have become due and payable, the principal of (or, if the Debt Securities of that series are Original Issue Discount Debt Securities, such portion of the principal amount as may be specified in the terms thereof), premium, if any, and interest on all the Debt Securities then Outstanding hereunder shall ipso facto become and be immediately due and payable without any declaration or other act on the part of the Trustee or any Holders, anything in this Indenture or in the Debt Securities contained to the contrary notwithstanding.

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        The Holders of a majority in aggregate principal amount of the Debt Securities of a particular series by written notice to the Trustee may rescind an acceleration and its consequences if the rescission would not conflict with any judgment or decree of a court of competent jurisdiction already rendered and if all existing Events of Default with respect to that series have been cured or waived except nonpayment of principal, premium, if any, or interest that has become due solely because of acceleration. Upon any such rescission, the parties hereto shall be restored respectively to their several positions and rights hereunder, and all rights, remedies and powers of the parties hereto shall continue as though no such proceeding had been taken.

        Section 6.02 Collection of Debt by Trustee, etc. If an Event of Default occurs and is continuing, the Trustee, in its own name and as trustee of an express trust, shall be entitled and empowered to institute any action or proceedings at law or in equity for the collection of the sums so due and unpaid or enforce the performance of any provision of the Debt Securities of the affected series or this Indenture, and may prosecute any such action or proceedings to judgment or final decree, and may enforce any such judgment or final decree against any of the Subsidiary Guarantors or the Partnership or any other obligor upon the Debt Securities of such series (and collect in the manner provided by law out of the property of any of the Subsidiary Guarantors or the Partnership or any other obligor upon the Debt Securities of such series wherever situated the moneys adjudged or decreed to be payable).

        In case there shall be pending proceedings for the bankruptcy or for the reorganization of any of the Subsidiary Guarantors or the Partnership or any other obligor upon the Debt Securities of any series under any Bankruptcy Law, or in case a Custodian shall have been appointed for its property, or in case of any other similar judicial proceedings relative to any of the Subsidiary Guarantors or the Partnership or any other obligor upon the Debt Securities of any series, its creditors or its property, the Trustee, irrespective of whether the principal of Debt Securities of any series shall then be due and payable as therein expressed or by declaration or otherwise and irrespective of whether the Trustee shall have made any demand pursuant to the provisions of this Section 6.02, shall be entitled and empowered, by intervention in such proceedings or otherwise, to file and prove a claim or claims for the whole amount of principal, premium, if any, and interest (or, if the Debt Securities of such series are Original Issue Discount Debt Securities, such portion of the principal amount as may be specified in the terms of such series) owing and unpaid in respect of the Debt Securities of such series, and to file such other papers or documents as may be necessary or advisable in order to have the claims of the Trustee (including any claim for reasonable compensation to the Trustee, its agents, attorneys and counsel, and for reimbursement of all expenses and liabilities incurred, and all advances made, by the Trustee except as a result of its negligence or bad faith) and of the Holders thereof allowed in any such judicial proceedings relative to any of the Subsidiary Guarantors or the Partnership, or any other obligor upon the Debt Securities of such series, its creditors or its property, and to collect and receive any moneys or other property payable or deliverable on any such claims, and to distribute all amounts received with respect to the claims of such Holders and of the Trustee on their behalf, and any receiver, assignee or trustee in bankruptcy or reorganization is hereby authorized by each of such Holders to make payments to the Trustee, and, in the event that the Trustee shall consent to the making of payments directly to such Holders, to pay to the Trustee such amount as shall be sufficient to cover reasonable compensation to the Trustee, its agents, attorneys and counsel, and all other reasonable expenses and liabilities incurred, and all advances made, by the Trustee except as a result of its negligence or bad faith.

        All rights of action and of asserting claims under this Indenture, or under any of the Debt Securities of any series, may be enforced by the Trustee without the possession of any such Debt Securities, or the production thereof in any trial or other proceedings relative thereto, and any such action or proceedings instituted by the Trustee shall be brought in its own name as trustee of an express trust, and any recovery of judgment (except for any amounts payable to the Trustee pursuant to

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Section 7.06) shall be for the ratable benefit of the Holders of all the Debt Securities in respect of which such action was taken.

        In case of an Event of Default hereunder the Trustee may in its discretion proceed to protect and enforce the rights vested in it by this Indenture by such appropriate judicial proceedings as the Trustee shall deem most effectual to protect and enforce any of such rights, either at law or in equity or in bankruptcy or otherwise, whether for the specific enforcement of any covenant or agreement contained in this Indenture or in aid of the exercise of any power granted in this Indenture, or to enforce any other legal or equitable right vested in the Trustee by this Indenture or by law.

        Section 6.03 Application of Moneys Collected by Trustee. Any moneys or other property collected by the Trustee pursuant to Section 6.02 with respect to Debt Securities of any series shall be applied, in the order following, at the date or dates fixed by the Trustee for the distribution of such moneys or other property, upon presentation of the several Debt Securities of such series in respect of which moneys or other property have been collected, and the notation thereon of the payment, if only partially paid, and upon surrender thereof if fully paid:

        FIRST: To the payment of all money due the Trustee pursuant to Section 7.06;

        SECOND: In case the principal of the Outstanding Debt Securities in respect of which such moneys have been collected shall not have become due, to the payment of interest on the Debt Securities of such series in the order of the maturity of the installments of such interest, with interest (to the extent that such interest has been collected by the Trustee) upon the overdue installments of interest at the rate or Yield to Maturity (in the case of Original Issue Discount Debt Securities) borne by the Debt Securities of such series, such payments to be made ratably to the Persons entitled thereto, without discrimination or preference;

        THIRD: In case the principal of the Outstanding Debt Securities in respect of which such moneys have been collected shall have become due, by declaration or otherwise, to the payment of the whole amount then owing and unpaid upon the Debt Securities of such series for principal and premium, if any, and interest, with interest on the overdue principal and premium, if any, and (to the extent that such interest has been collected by the Trustee) upon overdue installments of interest at the rate or Yield to Maturity (in the case of Original Issue Discount Debt Securities) borne by the Debt Securities of such series; and, in case such moneys shall be insufficient to pay in full the whole amount so due and unpaid upon the Debt Securities of such series, then to the payment of such principal and premium, if any, and interest, without preference or priority of principal and premium, if any, over interest, or of interest over principal and premium, if any, or of any installment of interest over any other installment of interest, or of any Debt Security of such series over any Debt Security of such series, ratably to the aggregate of such principal and premium, if any, and interest; and

        FOURTH: The remainder, if any, shall be paid to the Subsidiary Guarantors or the Partnership, as applicable, its successors or assigns, or to whomsoever may be lawfully entitled to receive the same, or as a court of competent jurisdiction may direct.

        The Trustee may fix a record date and payment date for any payment to Holders pursuant to this Section 6.03. At least 15 days before such record date, the Partnership shall mail to each Holder and the Trustee a notice that states the record date, the payment date and amount to be paid.

        Section 6.04 Limitation on Suits by Holders. No Holder of any Debt Security of any series shall have any right by virtue or by availing of any provision of this Indenture to institute any action or proceeding at law or in equity or in bankruptcy or otherwise, upon or under or with respect to this Indenture, or for the appointment of a receiver or trustee, or for any other remedy hereunder, unless such Holder previously shall have given to the Trustee written notice of an Event of Default with respect to Debt Securities of that same series and of the continuance thereof and unless the Holders of not less than 25% in aggregate principal amount of the Outstanding Debt Securities of that series shall

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have made written request upon the Trustee to institute such action or proceedings in respect of such Event of Default in its own name as Trustee hereunder and shall have offered to the Trustee such reasonable indemnity or security as it may require against the costs, expenses and liabilities to be incurred therein or thereby, and the Trustee, for 60 days after its receipt of such notice, request and offer of indemnity or security shall have failed to institute any such action or proceedings and no direction inconsistent with such written request shall have been given to the Trustee pursuant to Section 6.06; it being understood and intended, and being expressly covenanted by the Holder of every Debt Security with every other Holder and the Trustee, that no one or more Holders shall have any right in any manner whatever by virtue or by availing of any provision of this Indenture to affect, disturb or prejudice the rights of any Holders, or to obtain or seek to obtain priority over or preference to any other such Holder, or to enforce any right under this Indenture, except in the manner herein provided and for the equal, ratable and common benefit of all such Holders. For the protection and enforcement of the provisions of this Section 6.04, each and every Holder and the Trustee shall be entitled to such relief as can be given either at law or in equity.

        Notwithstanding any other provision in this Indenture, however, the right of any Holder of any Debt Security to receive payment of the principal of, and premium, if any, and (subject to Section 2.12) interest on, such Debt Security, on or after the respective due dates expressed in such Debt Security, and to institute suit for the enforcement of any such payment on or after such respective dates, shall not be impaired or affected without the consent of such Holder.

        Section 6.05 Remedies Cumulative; Delay or Omission in Exercise of Rights Not a Waiver of Default. All powers and remedies given by this Article VI to the Trustee or to the Holders shall, to the extent permitted by law, be deemed cumulative and not exclusive of any thereof or of any other powers and remedies available to the Trustee or the Holders, by judicial proceedings or otherwise, to enforce the performance or observance of the covenants and agreements contained in this Indenture, and no delay or omission of the Trustee or of any Holder to exercise any right or power accruing upon any Default occurring and continuing as aforesaid, shall impair any such right or power, or shall be construed to be a waiver of any such Default or an acquiescence therein; and, subject to the provisions of Section 6.04, every power and remedy given by this Article VI or by law to the Trustee or to the Holders may be exercised from time to time, and as often as shall be deemed expedient, by the Trustee or by the Holders.

        Section 6.06 Rights of Holders of Majority in Principal Amount of Debt Securities to Direct Trustee and to Waive Default. The Holders of not less than a majority in aggregate principal amount of the Debt Securities of any series at the time Outstanding shall have the right to direct the time, method and place of conducting any proceeding for any remedy available to the Trustee, or of exercising any right, trust or power conferred on the Trustee, with respect to the Debt Securities of such series; provided, however, that such direction shall not be otherwise than in accordance with law and the provisions of this Indenture, and that subject to the provisions of Section 7.01, the Trustee shall have the right to decline to follow any such direction if the Trustee being advised by counsel shall determine that the action so directed may not lawfully be taken or is inconsistent with any provision of this Indenture, or if the Trustee shall by a responsible officer or officers determine that the action so directed would involve it in personal liability or would be unduly prejudicial to Holders of Debt Securities of such series not taking part in such direction; and provided, further, however, that nothing in this Indenture contained shall impair the right of the Trustee to take any action deemed proper by the Trustee and which is not inconsistent with such direction by such Holders. The Holders of not less than a majority in aggregate principal amount of the Debt Securities of any series at the time Outstanding may on behalf of the Holders of all the Debt Securities of that series waive any past Default or Event of Default and its consequences for that series, except a Default or Event of Default in the payment of the principal of, and premium, if any, or interest on, any of the Debt Securities and a Default or Event of Default in respect of a provision that under Section 9.02 cannot be amended

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without the consent of each Holder affected thereby. In case of any such waiver, such Default shall cease to exist, any Event of Default arising therefrom shall be deemed to have been cured for every purpose of this Indenture, and the Subsidiary Guarantors, the Partnership, the Trustee and the Holders of the Debt Securities of that series shall be restored to their former positions and rights hereunder, respectively; but no such waiver shall extend to any subsequent or other Default or Event of Default or impair any right consequent thereon.

        Section 6.07 Trustee to Give Notice of Events of Defaults Known to It, but May Withhold Such Notice in Certain Circumstances. The Trustee shall, within 90 days after the occurrence of an Event of Default, or if later, within 30 days after the Trustee obtains actual knowledge of the Event of Default, with respect to a series of Debt Securities give to the Holders thereof, in the manner provided in Section 13.03, notice of all Events of Default with respect to such series known to the Trustee, unless such Events of Default shall have been cured or waived before the giving of such notice; provided, that, except in the case of an Event of Default in the payment of the principal of, or premium, if any, or interest on, any of the Debt Securities of such series or in the making of any sinking fund payment with respect to the Debt Securities of such series, the Trustee shall be protected in withholding such notice if and so long as the board of directors, the executive committee or a committee of directors or responsible officers of the Trustee in good faith determines that the withholding of such notice is in the interests of the Holders thereof.

        Section 6.08 Requirement of an Undertaking to Pay Costs in Certain Suits under the Indenture or Against the Trustee. All parties to this Indenture agree, and each Holder of any Debt Security by his acceptance thereof shall be deemed to have agreed, that any court may in its discretion require, in any suit for the enforcement of any right or remedy under this Indenture, or in any suit against the Trustee for any action taken or omitted by it as Trustee, the filing by any party litigant in such suit of an undertaking to pay the costs of such suit in the manner and to the extent provided in the TIA, and that such court may in its discretion assess reasonable costs, including reasonable attorneys' fees and expenses, against any party litigant in such suit, having due regard to the merits and good faith of the claims or defenses made by such party litigant; but the provisions of this Section 6.08 shall not apply to any suit instituted by the Trustee, to any suit instituted by any Holder, or group of Holders, holding in the aggregate more than 25 percent in principal amount of the Outstanding Debt Securities of that series or to any suit instituted by any Holder for the enforcement of the payment of the principal of, or premium, if any, or interest on, any Debt Security on or after the due date for such payment expressed in such Debt Security.

ARTICLE VII

CONCERNING THE TRUSTEE

        Section 7.01 Certain Duties and Responsibilities. The Trustee, prior to the occurrence of an Event of Default and after the curing or waiving of all Events of Default which may have occurred, undertakes to perform such duties and only such duties as are specifically set forth in this Indenture. In case an Event of Default has occurred (which has not been cured or waived), the Trustee shall exercise such of the rights and powers vested in it by this Indenture, and use the same degree of care and skill in their exercise, as a prudent man would exercise or use under the circumstances in the conduct of his own affairs.

        No provision of this Indenture shall be construed to relieve the Trustee from liability for its own negligent action, its own negligent failure to act, its own bad faith or its own willful misconduct, except that:

        (a)   this paragraph shall not be construed to limit the effect of the first paragraph of this Section 7.01;

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        (b)   prior to the occurrence of an Event of Default with respect to the Debt Securities of a series and after the curing or waiving of all Events of Default with respect to such series which may have occurred:

          (i)  the duties and obligations of the Trustee with respect to Debt Securities of any series shall be determined solely by the express provisions of this Indenture, and the Trustee shall not be liable except for the performance of such duties and obligations with respect to such series as are specifically set forth in this Indenture, and no implied covenants or obligations with respect to such series shall be read into this Indenture against the Trustee;

         (ii)  in the absence of bad faith on the part of the Trustee, the Trustee may conclusively rely, as to the truth of the statements and the correctness of the opinions expressed therein, upon any certificates or opinions furnished to the Trustee and conforming to the requirements of this Indenture; but in the case of any such certificates or opinions which by any provision hereof are specifically required to be furnished to the Trustee, the Trustee shall be under a duty to examine the same to determine whether or not they conform to the requirements of this Indenture; but the Trustee shall examine the evidence furnished to it pursuant to Sections 4.05 and 4.06 to determine whether or not such evidence conforms to the requirement of this Indenture;

        (iii)  the Trustee shall not be liable for an error of judgment made in good faith by a responsible officer, unless it shall be proved that the Trustee was negligent in ascertaining the pertinent facts; and

        (iv)  the Trustee shall not be liable with respect to any action taken or omitted to be taken by it with respect to Debt Securities of any series in good faith in accordance with the direction of the Holders of not less than a majority in aggregate principal amount of the Outstanding Debt Securities of that series relating to the time, method and place of conducting any proceeding for any remedy available to the Trustee, or exercising any trust or power conferred upon the Trustee, under this Indenture with respect to Debt Securities of such series.

        None of the provisions of this Indenture shall require the Trustee to expend or risk its own funds or otherwise incur any personal financial liability in the performance of any of its duties hereunder, or in the exercise of any of its rights or powers, if there shall be reasonable grounds for believing that repayment of such funds or adequate indemnity against such risk or liability is not reasonably assured to it.

        Whether or not therein expressly so provided, every provision of this Indenture relating to the conduct or affecting the liability of or affording protection to the Trustee shall be subject to the provisions of this Section.

        Section 7.02 Certain Rights of Trustee. Except as otherwise provided in Section 7.01:

        (a)   the Trustee may rely and shall be protected in acting or refraining from acting upon any resolution, certificate, statement, instrument, opinion, report, notice, request, direction, consent, order, bond, debenture, note or other paper or document (whether in its original or facsimile form) believed by it to be genuine and to have been signed or presented by the proper party or parties;

        (b)   any request, direction, order or demand of the Partnership mentioned herein shall be sufficiently evidenced by a Partnership Order (unless other evidence in respect thereof be herein specifically prescribed); and any resolution of the Board of Directors may be evidenced to the Trustee by a copy thereof certified by the Secretary or an Assistant Secretary of the Partnership;

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        (c)   the Trustee may consult with counsel, and the advice of such counsel or any Opinion of Counsel shall be full and complete authorization and protection in respect of any action taken or suffered or omitted by it hereunder in good faith and in accordance with such advice or Opinion of Counsel;

        (d)   the Trustee shall be under no obligation to exercise any of the rights or powers vested in it by this Indenture at the request, order or direction of any of the Holders of Debt Securities of any series pursuant to the provisions of this Indenture, unless such Holders shall have offered to the Trustee reasonable security or indemnity against the costs, expenses and liabilities which may be incurred therein or thereby;

        (e)   the Trustee shall not be liable for any action taken or omitted by it in good faith and reasonably believed by it to be authorized or within the discretion or rights or powers conferred upon it by this Indenture;

        (f)    prior to the occurrence of an Event of Default and after the curing of all Events of Default which may have occurred, the Trustee shall not be bound to make any investigation into the facts or matters stated in any resolution, certificate, statement, instrument, opinion, report, notice, request, direction, consent, order, approval or other paper or document, unless requested in writing to do so by the Holders of a majority in aggregate principal amount of the then Outstanding Debt Securities of a series affected by such matter; provided, however, that if the payment within a reasonable time to the Trustee of the costs, expenses or liabilities likely to be incurred by it in the making of such investigation is not, in the opinion of the Trustee, reasonably assured to the Trustee by the security afforded to it by the terms of this Indenture, the Trustee may require reasonable indemnity against such costs, expenses or liabilities as a condition to so proceeding, and the reasonable expense of every such investigation shall be paid by the Partnership or, if paid by the Trustee, shall be repaid by the Partnership upon demand;

        (g)   the Trustee may execute any of the trusts or powers hereunder or perform any duties hereunder either directly or by or through agents or attorneys and the Trustee shall not be responsible for any misconduct or negligence on the part of any agent or attorney appointed by it with due care hereunder; and

        (h)   if any property other than cash shall at any time be subject to a Lien in favor of the Holders, the Trustee, if and to the extent authorized by a receivership or bankruptcy court of competent jurisdiction or by the supplemental instrument subjecting such property to such Lien, shall be entitled to make advances for the purpose of preserving such property or of discharging tax Liens or other prior Liens or encumbrances thereon.

        Section 7.03 Trustee Not Liable for Recitals in Indenture or in Debt Securities. The recitals contained herein, in the Debt Securities (except the Trustee's certificate of authentication) shall be taken as the statements of the Partnership, and the Trustee assumes no responsibility for the correctness of the same. The Trustee makes no representations as to the validity or sufficiency of this Indenture or of the Debt Securities of any series, except that the Trustee represents that it is duly authorized to execute and deliver this Indenture, authenticate the Debt Securities and perform its obligations hereunder, and that the statements made by it or to be made by it in a Statement of Eligibility and Qualification on Form T-1 supplied to the Partnership are true and accurate. The Trustee shall not be accountable for the use or application by the Partnership of any of the Debt Securities or of the proceeds thereof.

        Section 7.04 Trustee, Paying Agent or Registrar May Own Debt Securities. The Trustee or any paying agent or Registrar, in its individual or any other capacity, may become the owner or pledgee of Debt Securities and subject to the provisions of the TIA relating to conflicts of interest and preferential claims may otherwise deal with the Partnership with the same rights it would have if it were not Trustee, paying agent or Registrar.

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        Section 7.05 Moneys Received by Trustee to Be Held in Trust. Subject to the provisions of Section 11.05, all moneys received by the Trustee shall, until used or applied as herein provided, be held in trust for the purposes for which they were received, but need not be segregated from other funds except to the extent required by law. The Trustee shall be under no liability for interest on any moneys received by it hereunder. So long as no Event of Default shall have occurred and be continuing, all interest allowed on any such moneys shall be paid from time to time to the Partnership upon a Partnership Order.

        Section 7.06 Compensation and Reimbursement. The Partnership covenants and agrees to pay in Dollars to the Trustee from time to time, and the Trustee shall be entitled to, reasonable compensation for all services rendered by it hereunder (which shall not be limited by any provision of law in regard to the compensation of a trustee of an express trust), and, except as otherwise expressly provided herein, the Partnership will pay or reimburse in Dollars the Trustee upon its request for all reasonable expenses, disbursements and advances incurred or made by the Trustee in accordance with any of the provisions of this Indenture (including the reasonable compensation and the expenses and disbursements of its agents, attorneys and counsel and of all Persons not regularly in its employ), including without limitation, Section 6.02, except any such expense, disbursement or advances as may arise from its negligence, willful misconduct or bad faith. The Partnership also covenants to indemnify in Dollars the Trustee for, and to hold it harmless against, any loss, liability or expense incurred without negligence, willful misconduct or bad faith on the part of the Trustee, arising out of or in connection with the acceptance or administration of this trust or trusts hereunder, including the reasonable costs and expenses of defending itself against any claim of liability in connection with the exercise or performance of any of its powers or duties hereunder. The obligations of the Partnership under this Section 7.06 to compensate and indemnify the Trustee and to pay or reimburse the Trustee for expenses, disbursements and advances shall constitute additional Debt hereunder and shall survive the satisfaction and discharge of this Indenture. The Partnership and the Holders agree that such additional Debt shall be secured by a Lien prior to that of the Debt Securities upon all property and funds held or collected by the Trustee, as such, except funds held in trust for the payment of principal of, and premium, if any, or interest on, particular Debt Securities.

        When the Trustee incurs expenses or renders services after an Event of Default specified in Section 6.01(e) or (f) occurs, the expenses and the compensation for the services are intended to constitute expenses of administration under any Bankruptcy Law.

        Section 7.07 Right of Trustee to Rely on an Officers' Certificate Where No Other Evidence Specifically Prescribed. Except as otherwise provided in Section 7.01, whenever in the administration of the provisions of this Indenture the Trustee shall deem it necessary or desirable that a matter be proved or established prior to taking or suffering or omitting any action hereunder, such matter (unless other evidence in respect thereof be herein specifically prescribed) may, in the absence of negligence or bad faith on the part of the Trustee, be deemed to be conclusively proved and established by an Officers' Certificate delivered to the Trustee and such certificate, in the absence of negligence or bad faith on the part of the Trustee, shall be full warrant to the Trustee for any action taken, suffered or omitted by it under the provisions of this Indenture upon the faith thereof.

        Section 7.08 Separate Trustee; Replacement of Trustee. The Partnership may, but need not, appoint a separate Trustee for any one or more series of Debt Securities. The Trustee may resign with respect to one or more or all series of Debt Securities at any time by giving notice to the Partnership. The Holders of a majority in principal amount of the Debt Securities of a particular series may remove the Trustee for such series and only such series by so notifying the Trustee and may appoint a successor Trustee. The Partnership shall remove the Trustee if:

        (a)   the Trustee fails to comply with Section 7.10;

        (b)   the Trustee is adjudged bankrupt or insolvent;

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        (c)   a Custodian takes charge of the Trustee or its property; or

        (d)   the Trustee otherwise becomes incapable of acting.

        If the Trustee resigns, is removed by the Partnership or by the Holders of a majority in principal amount of the Debt Securities of a particular series and such Holders do not reasonably promptly appoint a successor Trustee, or if a vacancy exists in the office of Trustee for any reason (the Trustee in such event being referred to herein as the retiring Trustee), the Partnership shall promptly appoint a successor Trustee. No resignation or removal of the Trustee and no appointment of a successor Trustee shall become effective until the acceptance of appointment by the successor Trustee in accordance with the applicable requirements of this Section 7.08.

        A successor Trustee shall deliver a written acceptance of its appointment to the retiring Trustee and to the Partnership. Thereupon the resignation or removal of the retiring Trustee shall become effective, and the successor Trustee shall have all the rights, powers and duties of the Trustee under this Indenture. The successor Trustee shall mail a notice of its succession to Holders of Debt Securities of each applicable series. The retiring Trustee shall promptly transfer all property held by it as Trustee to the successor Trustee, subject to the Lien provided for in Section 7.06.

        If a successor Trustee does not take office within 60 days after the retiring Trustee gives notice of resignation or is removed, the retiring Trustee or the Holders of 25% in principal amount of the Debt Securities of any applicable series may petition any court of competent jurisdiction for the appointment of a successor Trustee for the Debt Securities of such series.

        If the Trustee fails to comply with Section 7.10, any Holder of Debt Securities of any applicable series may petition any court of competent jurisdiction for the removal of the Trustee and the appointment of a successor Trustee for the Debt Securities of such series.

        Notwithstanding the replacement of the Trustee pursuant to this Section 7.08, the Partnership's obligations under Section 7.06 shall continue for the benefit of the retiring Trustee.

        In the case of the appointment hereunder of a separate or successor Trustee with respect to the Debt Securities of one or more series, the Partnership, any retiring Trustee and each successor or separate Trustee with respect to the Debt Securities of any applicable series shall execute and deliver an Indenture supplemental hereto (i) which shall contain such provisions as shall be deemed necessary or desirable to confirm that all the rights, powers, trusts and duties of any retiring Trustee with respect to the Debt Securities of any series as to which any such retiring Trustee is not retiring shall continue to be vested in such retiring Trustee and (ii) that shall add to or change any of the provisions of this Indenture as shall be necessary to provide for or facilitate the administration of the trusts hereunder by more than one trustee, it being understood that nothing herein or in such supplemental Indenture shall constitute such Trustees co-trustees of the same trust and that each such separate, retiring or successor Trustee shall be Trustee of a trust or trusts hereunder separate and apart from any trust or trusts hereunder administered by any other such Trustee.

        Section 7.09 Successor Trustee by Merger. If the Trustee consolidates with, merges or converts into, or transfers all or substantially all its corporate trust business or assets to, another corporation or banking association, the resulting, surviving or transferee corporation or banking association without any further act shall be the successor Trustee.

        In case at the time such successor or successors to the Trustee by merger, conversion, consolidation or transfer shall succeed to the trusts created by this Indenture any of the Debt Securities shall have been authenticated but not delivered, any such successor to the Trustee may adopt the certificate of authentication of any predecessor Trustee, and deliver such Debt Securities so authenticated; and in case at that time any of the Debt Securities shall not have been authenticated, any successor to the Trustee may authenticate such Debt Securities either in the name of any predecessor hereunder or in

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the name of the successor to the Trustee; and in all such cases such certificates shall have the full force which it is anywhere in the Debt Securities or in this Indenture provided that the certificate of the Trustee shall have.

        Section 7.10 Eligibility; Disqualification. The Trustee shall at all times satisfy the requirements of Section 310(a) of the TIA. The Trustee shall have a combined capital and surplus of at least $50,000,000 as set forth in its most recent published annual report of condition. No obligor upon the Debt Securities of a particular series or Person directly or indirectly controlling, controlled by or under common control with such obligor shall serve as Trustee for the Debt Securities of such series. The Trustee shall comply with Section 310(b) of the TIA; provided, however, that there shall be excluded from the operation of Section 310(b)(1) of the TIA this Indenture or any indenture or indentures under which other securities or certificates of interest or participation in other securities of the Partnership are outstanding if the requirements for such exclusion set forth in Section 310(b)(1) of the TIA are met.

        Section 7.11 Preferential Collection of Claims Against Partnership. The Trustee shall comply with Section 311(a) of the TIA, excluding any creditor relationship listed in Section 311(b) of the TIA. A Trustee who has resigned or been removed shall be subject to Section 311(a) of the TIA to the extent indicated therein.

        Section 7.12 Compliance with Tax Laws. The Trustee hereby agrees to comply with all U.S. Federal income tax information reporting and withholding requirements applicable to it with respect to payments of premium (if any) and interest on the Debt Securities, whether acting as Trustee, Registrar, paying agent or otherwise with respect to the Debt Securities.

ARTICLE VIII

CONCERNING THE HOLDERS

        Section 8.01 Evidence of Action by Holders. Whenever in this Indenture it is provided that the Holders of a specified percentage in aggregate principal amount of the Debt Securities of any or all series may take action (including the making of any demand or request, the giving of any direction, notice, consent or waiver or the taking of any other action) the fact that at the time of taking any such action the Holders of such specified percentage have joined therein may be evidenced (a) by any instrument or any number of instruments of similar tenor executed by Holders in Person or by agent or proxy appointed in writing, (b) by the record of the Holders voting in favor thereof at any meeting of Holders duly called and held in accordance with the provisions of Section 5.02, (c) by a combination of such instrument or instruments and any such record of such a meeting of Holders or (d) in the case of Debt Securities evidenced by a Global Security, by any electronic transmission or other message, whether or not in written format, that complies with the Depositary's applicable procedures.

        Section 8.02 Proof of Execution of Instruments and of Holding of Debt Securities. Subject to the provisions of Sections 7.01, 7.02 and 13.09, proof of the execution of any instrument by a Holder or his agent or proxy shall be sufficient if made in accordance with such reasonable rules and regulations as may be prescribed by the Trustee or in such manner as shall be satisfactory to the Trustee. The ownership of Debt Securities of any series shall be proved by the Debt Security Register or by a certificate of the Registrar for such series. The Trustee may require such additional proof of any matter referred to in this Section 8.02 as it shall deem necessary.

        Section 8.03 Who May Be Deemed Owner of Debt Securities. Prior to due presentment for registration of transfer of any Debt Security, the Partnership, the Subsidiary Guarantors, the Trustee, any paying agent and any Registrar may deem and treat the Person in whose name any Debt Security shall be registered upon the books of the Partnership as the absolute owner of such Debt Security (whether or not such Debt Security shall be overdue and notwithstanding any notation of ownership or

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other writing thereon) for the purpose of receiving payment of or on account of the principal of and premium, if any, and (subject to Section 2.12) interest on such Debt Security and for all other purposes, and none of the Partnership, the Subsidiary Guarantors or the Trustee nor any paying agent nor any Registrar shall be affected by any notice to the contrary; and all such payments so made to any such Holder for the time being, or upon his order, shall be valid and, to the extent of the sum or sums so paid, effectual to satisfy and discharge the liability for moneys payable upon any such Debt Security.

        None of the Partnership, the Subsidiary Guarantors, the Trustee, any paying agent or any Registrar will have any responsibility or liability for any aspect of the records relating to or payments made on account of beneficial ownership interests in a Global Security or for maintaining, supervising or reviewing any records relating to such beneficial ownership interests.

        Section 8.04 Instruments Executed by Holders Bind Future Holders. At any time prior to (but not after) the evidencing to the Trustee, as provided in Section 8.01, of the taking of any action by the Holders of the percentage in aggregate principal amount of the Debt Securities of any series specified in this Indenture in connection with such action and subject to the following paragraph, any Holder of a Debt Security which is shown by the evidence to be included in the Debt Securities the Holders of which have consented to such action may, by filing written notice with the Trustee at its corporate trust office and upon proof of holding as provided in Section 8.02, revoke such action so far as concerns such Debt Security. Except as aforesaid any such action taken by the Holder of any Debt Security shall be conclusive and binding upon such Holder and upon all future Holders and owners of such Debt Security and of any Debt Security issued upon transfer thereof or in exchange or substitution therefor, irrespective of whether or not any notation in regard thereto is made upon such Debt Security or such other Debt Securities. Any action taken by the Holders of the percentage in aggregate principal amount of the Debt Securities of any series specified in this Indenture in connection with such action shall be conclusively binding upon the Partnership, the Subsidiary Guarantors, the Trustee and the Holders of all the Debt Securities of such series.

        The Partnership may, but shall not be obligated to, fix a record date for the purpose of determining the Holders of Debt Securities entitled to give their consent or take any other action required or permitted to be taken pursuant to this Indenture. If a record date is fixed, then notwithstanding the immediately preceding paragraph, those Persons who were Holders of Debt Securities at such record date (or their duly designated proxies), and only those Persons, shall be entitled to give such consent or to revoke any consent previously given or to take any such action, whether or not such Persons continue to be Holders of Debt Securities after such record date. No such consent shall be valid or effective for more than 120 days after such record date unless the consent of the Holders of the percentage in aggregate principal amount of the Debt Securities of such series specified in this Indenture shall have been received within such 120-day period.

ARTICLE IX

SUPPLEMENTAL INDENTURES

        Section 9.01 Purposes for Which Supplemental Indenture May Be Entered into Without Consent of Holders. The Partnership and any Subsidiary Guarantors, when authorized by resolutions of the Board of Directors, and the Trustee may from time to time and at any time, without the consent of Holders, enter into an Indenture or Indentures supplemental hereto (which shall conform to the provisions of the TIA as in force at the date of the execution thereof) for one or more of the following purposes:

        (a)   to evidence the succession pursuant to Article X of another Person to the Partnership, or successive successions, and the assumption by the Successor Partnership (as defined in Section 10.01) of the covenants, agreements and obligations of the Partnership in this Indenture and in the Debt Securities;

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        (b)   to surrender any right or power herein conferred upon the Partnership or the Subsidiary Guarantors, to add to the covenants of the Partnership or the Subsidiary Guarantors such further covenants, restrictions, conditions or provisions for the protection of the Holders of all or any series of Debt Securities (and if such covenants are to be for the benefit of less than all series of Debt Securities, stating that such covenants are expressly being included solely for the benefit of such series) as the Board of Directors shall consider to be for the protection of the Holders of such Debt Securities, and to make the occurrence, or the occurrence and continuance, of a Default in any of such additional covenants, restrictions, conditions or provisions a Default or an Event of Default permitting the enforcement of all or any of the several remedies provided in this Indenture; provided, that in respect of any such additional covenant, restriction, condition or provision such supplemental Indenture may provide for a particular period of grace after Default (which period may be shorter or longer than that allowed in the case of other Defaults) or may provide for an immediate enforcement upon such Default or may limit the remedies available to the Trustee upon such Default or may limit the right of the Holders of a majority in aggregate principal amount of any or all series of Debt Securities to waive such Default;

        (c)   to cure any ambiguity or omission or to correct or supplement any provision contained herein, in any supplemental Indenture or in any Debt Securities of any series that may be defective or inconsistent with any other provision contained herein, in any supplemental Indenture or in the Debt Securities of such series; to convey, transfer, assign, mortgage or pledge any property to or with the Trustee, or to make such other provisions in regard to matters or questions arising under this Indenture as shall not adversely affect the interests of any Holders of Debt Securities of any series;

        (d)   to permit the qualification of this Indenture or any Indenture supplemental hereto under the TIA as then in effect, except that nothing herein contained shall permit or authorize the inclusion in any Indenture supplemental hereto of the provisions referred to in Section 316(a)(2) of the TIA;

        (e)   to permit or facilitate the issuance of Debt Securities of any series in uncertificated form;

        (f)    to reflect the release of any Subsidiary Guarantor in accordance with Article XIV;

        (g)   to add Subsidiary Guarantors with respect to any or all of the Debt Securities or to secure any or all of the Debt Securities or the Guarantee;

        (h)   to make any change that does not adversely affect the rights hereunder of any Holder;

        (i)    to add to, change or eliminate any of the provisions of this Indenture in respect of one or more series of Debt Securities; provided, however, that any such addition, change or elimination not otherwise permitted under this Section 9.01 shall neither apply to any Debt Security of any series created prior to the execution of such supplemental Indenture and entitled to the benefit of such provision nor modify the rights of the Holder of any such Debt Security with respect to such provision or shall become effective only when there is no such Debt Security Outstanding;

        (j)    to evidence and provide for the acceptance of appointment hereunder by a successor or separate Trustee with respect to the Debt Securities of one or more series and to add to or change any of the provisions of this Indenture as shall be necessary to provide for or facilitate the administration of the trusts hereunder by more than one Trustee; and

        (k)   to establish the form or terms of Debt Securities of any series as permitted by Sections 2.01 and 2.03.

        The Trustee is hereby authorized to join with the Partnership and the Subsidiary Guarantors in the execution of any such supplemental Indenture, to make any further appropriate agreements and stipulations which may be therein contained and to accept the conveyance, transfer, assignment, mortgage or pledge of any property thereunder, but the Trustee shall not be obligated to enter into any

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such supplemental Indenture which affects the Trustee's own rights, duties or immunities under this Indenture or otherwise.

        Any supplemental Indenture authorized by the provisions of this Section 9.01 may be executed by the Partnership, the Subsidiary Guarantors and the Trustee without the consent of the Holders of any of the Debt Securities at the time Outstanding, notwithstanding any of the provisions of Section 9.02.

        Section 9.02 Modification of Indenture with Consent of Holders of Debt Securities. Without notice to any Holder but with the consent (evidenced as provided in Section 8.01) of the Holders of not less than a majority in aggregate principal amount of the Outstanding Debt Securities of each series affected by such supplemental Indenture (including consents obtained in connection with a tender offer or exchange offer for any such series of Debt Securities), the Partnership and the Subsidiary Guarantors, when authorized by resolutions of the Board of Directors, and the Trustee may from time to time and at any time enter into an Indenture or Indentures supplemental hereto (which shall conform to the provisions of the TIA as in force at the date of execution thereof) for the purpose of adding any provisions to or changing in any manner or eliminating any of the provisions of this Indenture or of any supplemental Indenture or of modifying in any manner the rights of the Holders of the Debt Securities of such series; provided, that no such supplemental Indenture, without the consent of the Holders of each Debt Security so affected, shall: reduce the percentage in principal amount of Debt Securities of any series whose Holders must consent to an amendment; reduce the rate of or extend the time for payment of interest on any Debt Security; reduce the principal of or extend the Stated Maturity of any Debt Security; reduce any premium payable upon the redemption of any Debt Security or change the time at which any Debt Security may or shall be redeemed in accordance with Article III; make any Debt Security payable in currency other than the Dollar; impair the right of any Holder to receive payment of premium, if any, principal of and interest on such Holder's Debt Securities on or after the due dates therefor or to institute suit for the enforcement of any payment on or with respect to such Holder's Debt Securities; release any security that may have been granted in respect of the Debt Securities, other than in accordance with this Indenture; make any change in Section 6.06 or this Section 9.02; or, except as provided in Section 11.02(b) or Section 14.04, release the Subsidiary Guarantors other than as provided in this Indenture or modify the Guarantee in any manner adverse to the Holders.

        A supplemental Indenture which changes or eliminates any covenant or other provision of this Indenture which has been expressly included solely for the benefit of one or more particular series of Debt Securities or which modifies the rights of the Holders of Debt Securities of such series with respect to such covenant or other provision, shall be deemed not to affect the rights under this Indenture of the Holders of Debt Securities of any other series.

        Upon the request of the Partnership and the Subsidiary Guarantors, accompanied by a copy of resolutions of the Board of Directors authorizing the execution of any such supplemental Indenture, and upon the filing with the Trustee of evidence of the consent of Holders as aforesaid, the Trustee shall join with the Partnership in the execution of such supplemental Indenture unless such supplemental Indenture affects the Trustee's own rights, duties or immunities under this Indenture or otherwise, in which case the Trustee may in its discretion but shall not be obligated to enter into such supplemental Indenture.

        It shall not be necessary for the consent of the Holders under this Section 9.02 to approve the particular form of any proposed supplemental Indenture, but it shall be sufficient if such consent shall approve the substance thereof.

        After an amendment under this Section 9.02 requiring the consent of the Holders of any series of Debt Securities becomes effective, the Partnership shall mail to Holders of that series of Debt Securities of each series affected thereby a notice briefly describing such amendment. The failure to

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give such notice to any such Holders, or any defect therein, shall not impair or affect the validity of an amendment under this Section 9.02 with respect to other Holders.

        Section 9.03 Effect of Supplemental Indentures. Upon the execution of any supplemental Indenture pursuant to the provisions of this Article IX, this Indenture shall be and be deemed to be modified and amended in accordance therewith and the respective rights, limitations of rights, obligations, duties and immunities under this Indenture of the Trustee, the Partnership, the Subsidiary Guarantors and the Holders shall thereafter be determined, exercised and enforced hereunder subject in all respects to such modifications and amendments, and all the terms and conditions of any such supplemental Indenture shall be and be deemed to be part of the terms and conditions of this Indenture for any and all purposes.

        The Trustee, subject to the provisions of Sections 7.01 and 7.02, may receive an Officers' Certificate and an Opinion of Counsel as conclusive evidence that any such supplemental Indenture complies with the provisions of this Article IX.

        Section 9.04 Debt Securities May Bear Notation of Changes by Supplemental Indentures. Debt Securities of any series authenticated and delivered after the execution of any supplemental Indenture pursuant to the provisions of this Article IX may, and shall if required by the Trustee, bear a notation in form approved by the Trustee as to any matter provided for in such supplemental Indenture. New Debt Securities of any series so modified as to conform, in the opinion of the Trustee and the Board of Directors, to any modification of this Indenture contained in any such supplemental Indenture may be prepared and executed by the Partnership, authenticated by the Trustee and delivered in exchange for the Debt Securities of such series then Outstanding. Failure to make the appropriate notation or to issue a new Debt Security of such series shall not affect the validity of such amendment.

ARTICLE X

CONSOLIDATION, MERGER, SALE OR CONVEYANCE

        Section 10.01 Consolidations and Mergers of the Partnership. The Partnership shall not consolidate or amalgamate with or merge with or into any Person, or sell, convey, transfer, lease or otherwise dispose of all or substantially all its assets to any Person, whether in a single transaction or a series of related transactions, except (1) in accordance with the provisions of its Partnership agreement, and (2) unless: (a) either (i) the Partnership shall be the surviving Person in the case of a merger or (ii) the resulting, surviving or transferee Person if other than the Partnership (the "Successor Partnership"), shall be a Partnership, limited liability company or corporation organized and existing under the laws of the United States, any State thereof or the District of Columbia and the Successor Partnership shall expressly assume, by an Indenture supplemental hereto, executed and delivered to the Trustee, in form satisfactory to the Trustee, all the obligations of the Partnership under this Indenture and the Debt Securities according to their tenor; (b) immediately after giving effect to such transaction or series of transactions (and treating any Debt which becomes an obligation of the Successor Partnership or any Subsidiary of the Partnership as a result of such transaction as having been incurred by the Successor Partnership or such Subsidiary at the time of such transaction or series of transactions), no Default or Event of Default would occur or be continuing; (c) if the Partnership is not the continuing Person, then each Subsidiary Guarantor, unless it has become the Successor Partnership, shall confirm that its Guarantee shall continue to apply to the obligations under the Debt Securities and this Indenture; and (d) the Partnership shall have delivered to the Trustee an Officers' Certificate and an Opinion of Counsel, each stating that such consolidation, amalgamation, merger or disposition and such supplemental Indenture (if any) comply with this Indenture.

        Section 10.02 Rights and Duties of Successor Partnership. In case of any consolidation, amalgamation or merger where the Partnership is not the continuing Person, or disposition of all or substantially all of the assets of the Partnership in accordance with Section 10.01, the Successor Partnership shall

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succeed to and be substituted for the Partnership with the same effect as if it had been named herein as the respective party to this Indenture, and the predecessor entity shall be released from all liabilities and obligations under this Indenture and the Debt Securities, except that no such release will occur in the case of a lease of all or substantially all of the Partnership's assets. The Successor Partnership thereupon may cause to be signed, and may issue either in its own name or in the name of the Partnership, any or all the Debt Securities issuable hereunder which theretofore shall not have been signed by or on behalf of the Partnership and delivered to the Trustee; and, upon the order of the Successor Partnership, instead of the Partnership, and subject to all the terms, conditions and limitations in this Indenture prescribed, the Trustee shall authenticate and shall deliver any Debt Securities which previously shall have been signed and delivered by or on behalf of the Partnership to the Trustee for authentication, and any Debt Securities which the Successor Partnership thereafter shall cause to be signed and delivered to the Trustee for that purpose. All the Debt Securities so issued shall in all respects have the same legal rank and benefit under this Indenture as the Debt Securities theretofore or thereafter issued in accordance with the terms of this Indenture as though all such Debt Securities had been issued at the date of the execution hereof.

        In case of any such consolidation, amalgamation, merger, sale or disposition such changes in phraseology and form (but not in substance) may be made in the Debt Securities thereafter to be issued as may be appropriate.

ARTICLE XI

SATISFACTION AND DISCHARGE OF
INDENTURE; DEFEASANCE; UNCLAIMED MONEYS

        Section 11.01 Applicability of Article. The provisions of this Article XI relating to discharge or defeasance of Debt Securities shall be applicable to each series of Debt Securities except as otherwise specified pursuant to Section 2.03 for Debt Securities of such series.

        Section 11.02 Satisfaction and Discharge of Indenture; Defeasance.

        (a)   If at any time the Partnership shall have delivered to the Trustee for cancellation all Debt Securities of any series theretofore authenticated and delivered (other than any Debt Securities of such series which shall have been destroyed, lost or stolen and which shall have been replaced or paid as provided in Section 2.09 and Debt Securities for whose payment money has theretofore been deposited in trust and thereafter repaid to the Partnership as provided in Section 11.05) or all Debt Securities of such series not theretofore delivered to the Trustee for cancellation shall have become due and payable, or are by their terms to become due and payable within one year or are to be called for redemption within one year under arrangements satisfactory to the Trustee for the giving of notice of redemption, and the Partnership shall deposit with the Trustee as trust funds the entire amount in cash sufficient to pay at final maturity or upon redemption all Debt Securities of such series not theretofore delivered to the Trustee for cancellation, including principal and premium, if any, and interest due or to become due on such date of maturity or Redemption Date, as the case may be, and if in either case the Partnership shall also pay or cause to be paid all other sums payable hereunder by the Partnership, then this Indenture shall cease to be of further effect (except as to any surviving rights of registration of transfer or exchange of such Debt Securities herein expressly provided for) with respect to the Debt Securities of such series, and the Trustee, on demand of the Partnership accompanied by an Officers' Certificate and an Opinion of Counsel and at the cost and expense of the Partnership, shall execute proper instruments acknowledging satisfaction of and discharging this Indenture with respect to the Debt Securities of such series.

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        (b)   Subject to Sections 11.02(c), 11.03 and 11.07, the Partnership at any time may terminate, with respect to Debt Securities of a particular series, all its obligations under the Debt Securities of such series and this Indenture with respect to the Debt Securities of such series ("legal defeasance option") or the operation of (w) Sections 4.09 and 4.10, (x) any covenant made applicable to such Debt Securities pursuant to Section 2.03, (y) Sections 6.01(d), (g) and (h) and (z) as they relate to the Subsidiary Guarantors only, Sections 6.01(e) and (f) ("covenant defeasance option"). If the Partnership exercises either its legal defeasance option or its covenant defeasance option with respect to Debt Securities of a particular series that are entitled to the benefit of the Guarantee, the Guarantee will terminate with respect to that series of Debt Securities. The Partnership may exercise its legal defeasance option notwithstanding its prior exercise of its covenant defeasance option.

        If the Partnership exercises its legal defeasance option, payment of the Debt Securities of the defeased series may not be accelerated because of an Event of Default. If the Partnership exercises its covenant defeasance option, payment of the Debt Securities of the defeased series may not be accelerated because of an Event of Default specified in Sections 6.01(d), (g) and (h) and, with respect to the Subsidiary Guarantors only, Sections 6.01(e) and (f).

        Upon satisfaction of the conditions set forth herein and upon request of the Partnership, the Trustee shall acknowledge in writing the discharge of those obligations that the Partnership terminates.

        (c)   Notwithstanding clauses (a) and (b) above, the Partnership's obligations in Sections 2.07, 2.09, 4.02, 4.03, 4.04, the last sentence of 4.05(a), 4.06(a), 5.01, 7.06, 11.05, 11.06 and 11.07 shall survive until the Debt Securities of the defeased series have been paid in full. Thereafter, the Partnership's obligations in Sections 7.06, 11.05 and 11.06 shall survive.

        Section 11.03 Conditions of Defeasance. The Partnership may exercise its legal defeasance option or its covenant defeasance option with respect to Debt Securities of a particular series only if:

        (a)   the Partnership irrevocably deposits in trust with the Trustee money or U.S. Government Obligations for the payment of principal of, and premium, if any, and interest on, the Debt Securities of such series to final maturity or redemption, as the case may be;

        (b)   the Partnership delivers to the Trustee a certificate from a nationally recognized firm of independent accountants expressing their opinion that the payments of principal and interest when due and without reinvestment on the deposited U.S. Government Obligations plus any deposited money without investment will provide cash at such times and in such amounts as will be sufficient to pay the principal, premium, if any, and interest when due on all the Debt Securities of such series to final maturity or redemption, as the case may be;

        (c)   91 days pass after the deposit is made and during the 91-day period no Default specified in Section 6.01(e) or (f) with respect to the Partnership occurs which is continuing at the end of the period;

        (d)   no Default has occurred and is continuing on the date of such deposit and after giving effect thereto;

        (e)   the deposit does not constitute a default under any other agreement binding on the Partnership;

        (f)    the Partnership delivers to the Trustee an Opinion of Counsel to the effect that the trust resulting from the deposit does not constitute, or is qualified as, a regulated investment company under the Investment Partnership Act of 1940;

        (g)   in the event of the legal defeasance option, the Partnership shall have delivered to the Trustee an Opinion of Counsel stating that the Partnership has received from the Internal Revenue Service a ruling, or since the date of this Indenture there has been a change in the applicable Federal income tax

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law, in either case to the effect that, and based thereon such Opinion of Counsel shall confirm that, the Holders of Debt Securities of such series will not recognize income, gain or loss for Federal income tax purposes as a result of such defeasance and will be subject to Federal income tax on the same amounts, in the same manner and at the same times as would have been the case if such defeasance had not occurred;

        (h)   in the event of the covenant defeasance option, the Partnership shall have delivered to the Trustee an Opinion of Counsel to the effect that the Holders of Debt Securities of such series will not recognize income, gain or loss for Federal income tax purposes as a result of such covenant defeasance and will be subject to Federal income tax on the same amounts, in the same manner and at the same times as would have been the case if such covenant defeasance had not occurred; and

        (i)    the Partnership delivers to the Trustee an Officers' Certificate and an Opinion of Counsel, each stating that all conditions precedent to the defeasance and discharge of the Debt Securities of such series as contemplated by this Article XI have been complied with.

        Before or after a deposit, the Partnership may make arrangements satisfactory to the Trustee for the redemption of Debt Securities of such series at a future date in accordance with Article III.

        Section 11.04 Application of Trust Money. The Trustee shall hold in trust money or U.S. Government Obligations deposited with it pursuant to this Article XI. It shall apply the deposited money and the money from U.S. Government Obligations through any paying agent and in accordance with this Indenture to the payment of principal of, and premium, if any, and interest on, the Debt Securities of the defeased series.

        Section 11.05 Repayment to Partnership. The Trustee and any paying agent shall promptly turn over to the Partnership upon request any excess money or securities held by them at any time.

        Subject to any applicable abandoned property law, the Trustee and any paying agent shall pay to the Partnership upon request any money held by them for the payment of principal, premium or interest that remains unclaimed for two years, and, thereafter, Holders entitled to such money must look to the Partnership for payment as general creditors.

        Section 11.06 Indemnity for U.S. Government Obligations. The Partnership shall pay and shall indemnify the Trustee and the Holders against any tax, fee or other charge imposed on or assessed against deposited U.S. Government Obligations or the principal and interest received on such U.S. Government Obligations.

        Section 11.07 Reinstatement. If the Trustee or any paying agent is unable to apply any money or U.S. Government Obligations in accordance with this Article XI by reason of any legal proceeding or by reason of any order or judgment of any court or government authority enjoining, restraining or otherwise prohibiting such application, the Partnership's obligations under this Indenture and the Debt Securities of the defeased series shall be revived and reinstated as though no deposit had occurred pursuant to this Article XI until such time as the Trustee or any paying agent is permitted to apply all such money or U.S. Government Obligations in accordance with this Article XI.

ARTICLE XII

[RESERVED]

        This Article XII has been intentionally omitted.

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ARTICLE XIII

MISCELLANEOUS PROVISIONS

        Section 13.01 Successors and Assigns of Partnership Bound by Indenture. All the covenants, stipulations, promises and agreements in this Indenture contained by or in behalf of the Partnership, the Subsidiary Guarantors or the Trustee shall bind their respective successors and assigns, whether so expressed or not.

        Section 13.02 Acts of Board, Committee or Officer of Successor Partnership Valid. Any act or proceeding by any provision of this Indenture authorized or required to be done or performed by any board, committee or officer of the Partnership shall and may be done and performed with like force and effect by the like board, committee or officer of any Successor Partnership.

        Section 13.03 Required Notices or Demands. Any notice or communication by the Partnership, the Subsidiary Guarantors or the Trustee to the others is duly given if in writing and delivered in Person or mailed by registered or certified mail (return receipt requested), telecopier or overnight air courier guaranteeing next day delivery, to the other's address:

        If to the Partnership or any Subsidiary Guarantor:

MarkWest Energy Partners, L.P.
1515 Arapahoe Street
Tower 2,Suite 700
Denver, Colorado 80202
Attention: Andrew L. Schroeder

        If to the Trustee:

[            ]

        The Partnership, any Subsidiary Guarantor or the Trustee by notice to the others may designate additional or different addresses for subsequent notices or communications.

        All notices and communications shall be deemed to have been duly given: at the time delivered by hand, if personally delivered; five Business Days after being deposited in the mail, postage prepaid, if mailed; on the first Business Day on or after being sent, if telecopied and the sender receives confirmation of successful transmission; and the next Business Day after timely delivery to the courier, if sent by overnight air courier guaranteeing next day delivery.

        Any notice required or permitted to a Holder by the Partnership, any Subsidiary Guarantor or the Trustee pursuant to the provisions of this Indenture shall be deemed to be properly mailed by being deposited postage prepaid in a post office letter box in the United States addressed to such Holder at the address of such Holder as shown on the Debt Security Register. Any report pursuant to Section 313 of the TIA shall be transmitted in compliance with subsection (c) therein.

        Notwithstanding the foregoing, any notice to Holders of Floating Rate Securities regarding the determination of a periodic rate of interest, if such notice is required pursuant to Section 2.03, shall be sufficiently given if given in the manner specified pursuant to Section 2.03.

        In the event of suspension of regular mail service or by reason of any other cause it shall be impracticable to give notice by mail, then such notification as shall be given with the approval of the Trustee shall constitute sufficient notice for every purpose hereunder.

        In the event it shall be impracticable to give notice by publication, then such notification as shall be given with the approval of the Trustee shall constitute sufficient notice for every purpose hereunder.

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        Failure to mail a notice or communication to a Holder or any defect in it or any defect in any notice by publication as to a Holder shall not affect the sufficiency of such notice with respect to other Holders. If a notice or communication is mailed or published in the manner provided above, it is conclusively presumed duly given.

        Section 13.04 Indenture and Debt Securities to Be Construed in Accordance with the Laws of the State of New York. THIS INDENTURE, EACH DEBT SECURITY AND THE GUARANTEE SHALL BE DEEMED TO BE NEW YORK CONTRACTS, AND FOR ALL PURPOSES SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF SAID STATE.

        Section 13.05 Officers' Certificate and Opinion of Counsel to Be Furnished upon Application or Demand by the Partnership. Upon any application or demand by the Partnership to the Trustee to take any action under any of the provisions of this Indenture, the Partnership shall furnish to the Trustee an Officers' Certificate stating that all conditions precedent provided for in this Indenture relating to the proposed action have been complied with and an Opinion of Counsel stating that, in the opinion of such counsel, all such conditions precedent have been complied with, except that in the case of any such application or demand as to which the furnishing of such document is specifically required by any provision of this Indenture relating to such particular application or demand, no additional certificate or opinion need be furnished.

        Each certificate or opinion provided for in this Indenture and delivered to the Trustee with respect to compliance with a condition or covenant provided for in this Indenture shall include (a) a statement that the Person making such certificate or opinion has read such covenant or condition, (b) a brief statement as to the nature and scope of the examination or investigation upon which the statements or opinions contained in such certificate or opinion are based, (c) a statement that, in the opinion of such Person, he has made such examination or investigation as is necessary to enable him to express an informed opinion as to whether or not such covenant or condition has been complied with and (d) a statement as to whether or not, in the opinion of such Person, such condition or covenant has been complied with.

        Section 13.06 Payments Due on Legal Holidays. In any case where the date of maturity of interest on or principal of and premium, if any, on the Debt Securities of a series or the date fixed for redemption or repayment of any Debt Security or the making of any sinking fund payment shall not be a Business Day at any Place of Payment for the Debt Securities of such series, then payment of interest or principal and premium, if any, or the making of such sinking fund payment need not be made on such date at such Place of Payment, but may be made on the next succeeding Business Day at such Place of Payment with the same force and effect as if made on the date of maturity or the date fixed for redemption, and no interest shall accrue for the period after such date. If a record date is not a Business Day, the record date shall not be affected.

        Section 13.07 Provisions Required by TIA to Control. If and to the extent that any provision of this Indenture limits, qualifies or conflicts with another provision included in this Indenture which is required to be included in this Indenture by any of Sections 310 to 318, inclusive, of the TIA, such required provision shall control.

        Section 13.08 Computation of Interest on Debt Securities. Interest, if any, on the Debt Securities shall be computed on the basis of a 360-day year of twelve 30-day months, except as may otherwise be provided pursuant to Section 2.03.

        Section 13.09 Rules by Trustee, Paying Agent and Registrar. The Trustee may make reasonable rules for action by or a meeting of Holders. The Registrar and any paying agent may make reasonable rules for their functions.

        Section 13.10 No Recourse Against Others. The Partnership and its directors, officers, employees, incorporators and capital stockholders, as such, shall have no liability for any obligations of the

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Subsidiary Guarantors or the Partnership under the Debt Securities, this Indenture or the Guarantee or for any claim based on, in respect of, or by reason of, such obligations or their creation. By accepting a Debt Security, each Holder shall be deemed to have waived and released all such liability. The waiver and release shall be part of the consideration for the issue of the Debt Securities.

        Section 13.11 Severability. In case any provision in this Indenture or the Debt Securities shall be invalid, illegal or unenforceable, the validity, legality and enforceability of the remaining provisions shall not in any way be affected or impaired thereby.

        Section 13.12 Effect of Headings. The article and section headings herein and in the Table of Contents are for convenience only and shall not affect the construction hereof.

        Section 13.13 Indenture May Be Executed in Counterparts. This Indenture may be executed in any number of counterparts, each of which shall be an original; but such counterparts shall together constitute but one and the same instrument.

ARTICLE XIV

GUARANTEE

        Section 14.01 Unconditional Guarantee.

        (a)   Notwithstanding any provision of this Article XIV to the contrary, the provisions of this Article XIV shall be applicable only to, and inure solely to the benefit of, the Debt Securities of any series designated, pursuant to Section 2.03, as entitled to the benefits of the Guarantee of each of the Subsidiary Guarantors.

        (b)   For value received, each of the Subsidiary Guarantors hereby fully, unconditionally and absolutely guarantees (the "Guarantee") to the Holders and to the Trustee the due and punctual payment of the principal of, and premium, if any, and interest on the Debt Securities and all other amounts due and payable under this Indenture and the Debt Securities by the Partnership, when and as such principal, premium, if any, and interest shall become due and payable, whether at the Stated Maturity or by declaration of acceleration, call for redemption or otherwise, according to the terms of the Debt Securities and this Indenture, subject to the limitations set forth in Section 14.03.

        (c)   Failing payment when due of any amount guaranteed pursuant to the Guarantee, for whatever reason, each of the Subsidiary Guarantors will be jointly and severally obligated to pay the same immediately. The Guarantee hereunder is intended to be a general, unsecured, senior obligation of each of the Subsidiary Guarantors and will rank pari passu in right of payment with all Debt of each Subsidiary Guarantor that is not, by its terms, expressly subordinated in right of payment to the Guarantee. Each of the Subsidiary Guarantors hereby agrees that its obligations hereunder shall be full, unconditional and absolute, irrespective of the validity, regularity or enforceability of the Debt Securities, the Guarantee (including the Guarantee of any other Subsidiary Guarantor) or this Indenture, the absence of any action to enforce the same, any waiver or consent by any Holder of the Debt Securities with respect to any provisions hereof or thereof, the recovery of any judgment against the Partnership or any other Subsidiary Guarantor, or any action to enforce the same or any other circumstances which might otherwise constitute a legal or equitable discharge or defense of any of the Subsidiary Guarantors. Each of the Subsidiary Guarantors hereby agrees that in the event of a default in payment of the principal of, or premium, if any, or interest on the Debt Securities, whether at the Stated Maturity or by declaration of acceleration, call for redemption or otherwise, legal proceedings may be instituted by the Trustee on behalf of the Holders or, subject to Section 6.04, by the Holders, on the terms and conditions set forth in this Indenture, directly against such Subsidiary Guarantor to enforce the Guarantee without first proceeding against the Partnership or any other Subsidiary Guarantor.

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        (d)   The obligations of each of the Subsidiary Guarantors under this Article XIV shall be as aforesaid full, unconditional and absolute and shall not be impaired, modified, released or limited by any occurrence or condition whatsoever, including, without limitation, (A) any compromise, settlement, release, waiver, renewal, extension, indulgence or modification of, or any change in, any of the obligations and liabilities of the Partnership or any of the Subsidiary Guarantors contained in the Debt Securities or this Indenture, (B) any impairment, modification, release or limitation of the liability of the Partnership, any of the Subsidiary Guarantors or any of their estates in bankruptcy, or any remedy for the enforcement thereof, resulting from the operation of any present or future provision of any applicable Bankruptcy Law, as amended, or other statute or from the decision of any court, (C) the assertion or exercise by the Partnership, any of the Subsidiary Guarantors or the Trustee of any rights or remedies under the Debt Securities or this Indenture or their delay in or failure to assert or exercise any such rights or remedies, (D) the assignment or the purported assignment of any property as security for the Debt Securities, including all or any part of the rights of the Partnership or any of the Subsidiary Guarantors under this Indenture, (E) the extension of the time for payment by the Partnership or any of the Subsidiary Guarantors of any payments or other sums or any part thereof owing or payable under any of the terms and provisions of the Debt Securities or this Indenture or of the time for performance by the Partnership or any of the Subsidiary Guarantors of any other obligations under or arising out of any such terms and provisions or the extension or the renewal of any thereof, (F) the modification or amendment (whether material or otherwise) of any duty, agreement or obligation of the Partnership or any of the Subsidiary Guarantors set forth in this Indenture, (G) the voluntary or involuntary liquidation, dissolution, sale or other disposition of all or substantially all of the assets, marshaling of assets and liabilities, receivership, insolvency, bankruptcy, assignment for the benefit of creditors, reorganization, arrangement, composition or readjustment of, or other similar proceeding affecting, the Partnership or any of the Subsidiary Guarantors or any of their respective assets, or the disaffirmance of the Debt Securities, the Guarantee or this Indenture in any such proceeding, (H) the release or discharge of the Partnership or any of the Subsidiary Guarantors from the performance or observance of any agreement, covenant, term or condition contained in any of such instruments by operation of law, (I) the unenforceability of the Debt Securities, the Guarantee or this Indenture or (J) any other circumstances (other than payment in full or discharge of all amounts guaranteed pursuant to the Guarantee) which might otherwise constitute a legal or equitable discharge of a surety or guarantor.

        (e)   Each of the Subsidiary Guarantors hereby (A) waives diligence, presentment, demand of payment, filing of claims with a court in the event of the merger, insolvency or bankruptcy of the Partnership or any of the Subsidiary Guarantors, and all demands whatsoever, (B) acknowledges that any agreement, instrument or document evidencing the Guarantee may be transferred and that the benefit of its obligations hereunder shall extend to each holder of any agreement, instrument or document evidencing the Guarantee without notice to it and (C) covenants that the Guarantee will not be discharged except by complete performance of the Guarantee. Each of the Subsidiary Guarantors further agrees that if at any time all or any part of any payment theretofore applied by any Person to the Guarantee is, or must be, rescinded or returned for any reason whatsoever, including without limitation, the insolvency, bankruptcy or reorganization of the Partnership or any of the Subsidiary Guarantors, the Guarantee shall, to the extent that such payment is or must be rescinded or returned, be deemed to have continued in existence notwithstanding such application, and the Guarantee shall continue to be effective or be reinstated, as the case may be, as though such application had not been made.

        (f)    Each of the Subsidiary Guarantors shall be subrogated to all rights of the Holders and the Trustee against the Partnership in respect of any amounts paid by such Subsidiary Guarantor pursuant to the provisions of this Indenture, provided, however, that such Subsidiary Guarantor, shall not be entitled to enforce or to receive any payments arising out of, or based upon, such right of subrogation until all of the Debt Securities and the Guarantee shall have been paid in full or discharged.

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        Section 14.02 Execution and Delivery of Guarantee. To further evidence the Guarantee set forth in Section 14.01, each of the Subsidiary Guarantors hereby agrees that a notation relating to such Guarantee, substantially in the form attached hereto as Annex A, shall be endorsed on each Debt Security entitled to the benefits of the Guarantee authenticated and delivered by the Trustee and executed by either manual or facsimile signature of an officer of such Subsidiary Guarantor, or in the case of a Subsidiary Guarantor that is a limited Partnership, an officer of the Partnership of each Subsidiary Guarantor. Each of the Subsidiary Guarantors hereby agrees that the Guarantee set forth in Section 14.01 shall remain in full force and effect notwithstanding any failure to endorse on each Debt Security a notation relating to the Guarantee. If any officer of any Subsidiary Guarantor, or in the case of a Subsidiary Guarantor that is a limited Partnership, any officer of the Partnership of the Subsidiary Guarantor, whose signature is on this Indenture or a Debt Security no longer holds that office at the time the Trustee authenticates such Debt Security or at any time thereafter, the Guarantee of such Debt Security shall be valid nevertheless. The delivery of any Debt Security by the Trustee, after the authentication thereof hereunder, shall constitute due delivery of the Guarantee set forth in this Indenture on behalf of the Subsidiary Guarantors.

        The Trustee hereby accepts the trusts in this Indenture upon the terms and conditions herein set forth.

        Section 14.03 Limitation on Subsidiary Guarantors' Liability. Each Subsidiary Guarantor and by its acceptance hereof each Holder of a Debt Security entitled to the benefits of the Guarantee hereby confirm that it is the intention of all such parties that the guarantee by such Subsidiary Guarantor pursuant to the Guarantee not constitute a fraudulent transfer or conveyance for purposes of any Federal or state law. To effectuate the foregoing intention, the Holders of a Debt Security entitled to the benefits of the Guarantee and the Subsidiary Guarantors hereby irrevocably agree that the obligations of each Subsidiary Guarantor under the Guarantee shall be limited to the maximum amount as will, after giving effect to all other contingent and fixed liabilities of such Subsidiary Guarantor and to any collections from or payments made by or on behalf of any other Subsidiary Guarantor in respect of the obligations of such other Subsidiary Guarantor under the Guarantee, not result in the obligations of such Subsidiary Guarantor under the Guarantee constituting a fraudulent conveyance or fraudulent transfer under Federal or state law.

        Section 14.04 Release of Subsidiary Guarantors from Guarantee.

        (a)   Notwithstanding any other provisions of this Indenture, the Guarantee of any Subsidiary Guarantor may be released upon the terms and subject to the conditions set forth in Section 11.02(b) and in this Section 14.04. Provided that no Default shall have occurred and shall be continuing under this Indenture, the Guarantee incurred by a Subsidiary Guarantor pursuant to this Article XIV shall be unconditionally released and discharged (i) automatically upon (A) any sale, exchange or transfer, whether by way of merger or otherwise, to any Person that is not an Affiliate of the Partnership, of all of the Partnership's direct or indirect limited Partnership or other equity interests in such Subsidiary Guarantor (provided such sale, exchange or transfer is not prohibited by this Indenture) or (B) the merger of such Subsidiary Guarantor into the Partnership or any other Subsidiary Guarantor or the liquidation and dissolution of such Subsidiary Guarantor (in each case to the extent not prohibited by this Indenture) or (ii) following delivery of a written notice of such release or discharge by the Partnership to the Trustee, upon the release or discharge of all guarantees by such Subsidiary Guarantor of any Debt of the Partnership other than obligations arising under this Indenture and any Debt Securities issued hereunder, except a discharge or release by or as a result of payment under such guarantees.

        (b)   The Trustee shall deliver an appropriate instrument evidencing any release of a Subsidiary Guarantor from the Guarantee upon receipt of a written request of the Partnership accompanied by an Officers' Certificate and an Opinion of Counsel to the effect that the Subsidiary Guarantor is entitled

46

to such release in accordance with the provisions of this Indenture. Any Subsidiary Guarantor not so released shall remain liable for the full amount of principal of (and premium, if any) and interest on the Debt Securities entitled to the benefits of the Guarantee as provided in this Indenture, subject to the limitations of Section 14.03.

        Section 14.05 Subsidiary Guarantor Contribution. In order to provide for just and equitable contribution among the Subsidiary Guarantors, the Subsidiary Guarantors hereby agree, inter se, that in the event any payment or distribution is made by any Subsidiary Guarantor (a "Funding Guarantor") under the Guarantee, such Funding Guarantor shall be entitled to a contribution from each other Subsidiary Guarantor (if any) in a pro rata amount based on the net assets of each Subsidiary Guarantor (including the Funding Guarantor) for all payments, damages and expenses incurred by that Funding Guarantor in discharging the Partnership's obligations with respect to the Debt Securities or any other Subsidiary Guarantor's obligations with respect to the Guarantee.

[Remainder of This Page Intentionally Left Blank.]

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        IN WITNESS WHEREOF, the parties hereto have caused this Indenture to be duly executed, all as of the day and year first above written.

MARKWEST ENERGY PARTNERS, L.P.
By:	MarkWest Energy GP, L.L.C., its General Partner
By:
	[            ] Vice President and Chief Financial Officer

[NAME OF SUBSIDIARY GUARANTOR(S)]

By:

Name:

Title:

By:

Name:

Title:

Signature Page to Senior Indenture

ANNEX A

NOTATION OF GUARANTEE

        Each of the Subsidiary Guarantors (which term includes any successor Person under the Indenture), has fully, unconditionally and absolutely guaranteed, to the extent set forth in the Indenture and subject to the provisions in the Indenture, the due and punctual payment of the principal of, and premium, if any, and interest on the Debt Securities and all other amounts due and payable under the Indenture and the Debt Securities by the Partnership.

        The obligations of the Subsidiary Guarantors to the Holders of Debt Securities and to the Trustee pursuant to the Guarantee and the Indenture are expressly set forth in Article XIV of the Indenture and reference is hereby made to the Indenture for the precise terms of the Guarantee.

[NAME OF SUBSIDIARY GUARANTOR(S)]

By:

Name:

Title:

Annex A

QuickLinks

Exhibit 4.24

CROSS-REFERENCE TABLE
TABLE OF CONTENTS
RECITALS OF THE COMPANY AND ANY SUBSIDIARY GUARANTORS
ARTICLE I DEFINITIONS AND INCORPORATION BY REFERENCE
ARTICLE II DEBT SECURITIES
TRUSTEE'S CERTIFICATE OF AUTHENTICATION
ARTICLE III REDEMPTION OF DEBT SECURITIES
ARTICLE IV PARTICULAR COVENANTS OF THE COMPANY
ARTICLE V HOLDERS' LISTS AND REPORTS BY THE TRUSTEE
ARTICLE VI REMEDIES OF THE TRUSTEE AND HOLDERS IN EVENT OF DEFAULT
ARTICLE VII CONCERNING THE TRUSTEE
ARTICLE VIII CONCERNING THE HOLDERS
ARTICLE IX SUPPLEMENTAL INDENTURES
ARTICLE X CONSOLIDATION, MERGER, SALE OR CONVEYANCE
ARTICLE XI SATISFACTION AND DISCHARGE OF INDENTURE; DEFEASANCE; UNCLAIMED MONEYS
ARTICLE XII [RESERVED]
ARTICLE XIII MISCELLANEOUS PROVISIONS
ARTICLE XIV GUARANTEE

ANNEX A

NOTATION OF GUARANTEE

EX-4.25

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Exhibit 4.25

[Form of Subordinated Indenture]

MARKWEST ENERGY PARTNERS, L.P.
as Issuer,
any Subsidiary Guarantors party hereto,
and
[                        ],
as Trustee
INDENTURE
Dated as of
Debt Securities

CROSS-REFERENCE TABLE

	TIA Section			Indenture Section
310		(a	)	7.10
		(b	)	7.10
		(c	)	N.A.
311		(a	)	7.11
		(b	)	7.11
		(c	)	N.A.
312		(a	)	5.01
		(b	)	5.02
		(c	)	5.02
313		(a	)	5.03
		(b	)	5.03
		(c	)	13.03
		(d	)	5.03
314		(a	)	4.05
		(b	)	N.A.
		(c	)(1)	13.05
		(c	)(2)	13.05
		(c	)(3)	N.A.
		(d	)	N.A.
		(e	)	13.05
		(f	)	N.A.
315		(a	)	7.01
		(b	)	6.07 & 13.03
		(c	)	7.01
		(d	)	7.01
		(e	)	6.08
316		(a	) (last sentence)	1.01
		(a	)(1)(A)	6.06
		(a	)(1)(B)	6.06
		(a	)(2)	9.01(d)
		(b	)	6.04
		(c	)	5.04
317		(a	)(1)	6.02
		(a	)(2)	6.02
		(b	)	4.04
318		(a	)	13.07

N.A. means Not Applicable

NOTE: This Cross-Reference table shall not, for any purpose, be deemed part of this Indenture.

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TABLE OF CONTENTS

ARTICLE I DEFINITIONS AND INCORPORATION BY REFERENCE
Section 1.01	Definitions	1
Section 1.02	Other Definitions	6
Section 1.03	Incorporation by Reference of Trust Indenture Act	6
Section 1.04	Rules of Construction	6
ARTICLE II DEBT SECURITIES
Section 2.01	Forms Generally	6
Section 2.02	Form of Trustee's Certificate of Authentication	7
Section 2.03	Principal Amount; Issuable in Series	7
Section 2.04	Execution of Debt Securities	9
Section 2.05	Authentication and Delivery of Debt Securities	9
Section 2.06	Denomination of Debt Securities	10
Section 2.07	Registration of Transfer and Exchange	11
Section 2.08	Temporary Debt Securities	12
Section 2.09	Mutilated, Destroyed, Lost or Stolen Debt Securities	12
Section 2.10	Cancellation of Surrendered Debt Securities	13
Section 2.11	Provisions of the Indenture and Debt Securities for the Sole Benefit of the Parties and the Holders	13
Section 2.12	Payment of Interest; Interest Rights Preserved	13
Section 2.13	Securities Denominated in Dollars	13
Section 2.14	Wire Transfers	13
Section 2.15	Securities Issuable in the Form of a Global Security	14
Section 2.16	Medium Term Securities	16
Section 2.17	Defaulted Interest	16
Section 2.18	CUSIP Numbers	17
ARTICLE III REDEMPTION OF DEBT SECURITIES
Section 3.01	Applicability of Article	17
Section 3.02	Notice of Redemption; Selection of Debt Securities	17
Section 3.03	Payment of Debt Securities Called for Redemption	19
Section 3.04	Mandatory and Optional Sinking Funds	19
Section 3.05	Redemption of Debt Securities for Sinking Fund	19
ARTICLE IV PARTICULAR COVENANTS OF THE COMPANY
Section 4.01	Payment of Principal of, and Premium, If Any, and Interest on, Debt Securities	21
Section 4.02	Maintenance of Offices or Agencies for Registration of Transfer, Exchange and Payment of Debt Securities	21
Section 4.03	Appointment to Fill a Vacancy in the Office of Trustee	21
Section 4.04	Duties of Paying Agents, etc	21
Section 4.05	SEC Reports; Financial Statements	22
Section 4.06	Compliance Certificate	23
Section 4.07	Further Instruments and Acts	23
Section 4.08	Existence	23
Section 4.09	Maintenance of Properties	23

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Section 4.10	Payment of Taxes and Other Claims	24
Section 4.11	Waiver of Certain Covenants	24
ARTICLE V HOLDERS' LISTS AND REPORTS BY THE TRUSTEE
Section 5.01	Partnership to Furnish Trustee Information as to Names and Addresses of Holders; Preservation of Information	24
Section 5.02	Communications to Holders	24
Section 5.03	Reports by Trustee	24
Section 5.04	Record Dates for Action by Holders	25
ARTICLE VI REMEDIES OF THE TRUSTEE AND HOLDERS IN EVENT OF DEFAULT
Section 6.01	Events of Default	25
Section 6.02	Collection of Debt by Trustee, etc	27
Section 6.03	Application of Moneys Collected by Trustee	28
Section 6.04	Limitation on Suits by Holders	29
Section 6.05	Remedies Cumulative; Delay or Omission in Exercise of Rights Not a Waiver of Default	29
Section 6.06	Rights of Holders of Majority in Principal Amount of Debt Securities to Direct Trustee and to Waive Default	30
Section 6.07	Trustee to Give Notice of Events of Defaults Known to It, but May Withhold Such Notice in Certain Circumstances	30
Section 6.08	Requirement of an Undertaking to Pay Costs in Certain Suits under the Indenture or Against the Trustee	30
ARTICLE VII CONCERNING THE TRUSTEE
Section 7.01	Certain Duties and Responsibilities	31
Section 7.02	Certain Rights of Trustee. Except as otherwise provided in Section 7.01	32
Section 7.03	Trustee Not Liable for Recitals in Indenture or in Debt Securities	33
Section 7.04	Trustee, Paying Agent or Registrar May Own Debt Securities	33
Section 7.05	Moneys Received by Trustee to Be Held in Trust	33
Section 7.06	Compensation and Reimbursement	33
Section 7.07	Right of Trustee to Rely on an Officers' Certificate Where No Other Evidence Specifically Prescribed	34
Section 7.08	Separate Trustee; Replacement of Trustee	34
Section 7.09	Successor Trustee by Merger	35
Section 7.10	Eligibility; Disqualification	35
Section 7.11	Preferential Collection of Claims Against Partnership	35
Section 7.12	Compliance with Tax Laws	35
ARTICLE VIII CONCERNING THE HOLDERS
Section 8.01	Evidence of Action by Holders	35
Section 8.02	Proof of Execution of Instruments and of Holding of Debt Securities	36
Section 8.03	Who May Be Deemed Owner of Debt Securities	36
Section 8.04	Instruments Executed by Holders Bind Future Holders	36
ARTICLE IX SUPPLEMENTAL INDENTURES
Section 9.01	Purposes for Which Supplemental Indenture May Be Entered into Without Consent of Holders	37

iii

Section 9.02		Modification of Indenture with Consent of Holders of Debt Securities	38
Section 9.03		Effect of Supplemental Indentures	39
Section 9.04		Debt Securities May Bear Notation of Changes by Supplemental Indentures	40
ARTICLE X CONSOLIDATION, MERGER, SALE OR CONVEYANCE
Section 10.01		Consolidations and Mergers of the Partnership	40
Section 10.02		Rights and Duties of Successor Partnership	40
	ARTICLE XI SATISFACTION AND DISCHARGE OF INDENTURE; DEFEASANCE; UNCLAIMED MONEYS
Section 11.01		Applicability of Article	41
Section 11.02		Satisfaction and Discharge of Indenture; Defeasance	41
Section 11.03		Application of Trust Money	43
Section 11.04		Repayment to Partnership	43
Section 11.05		Indemnity for U.S. Government Obligations	43
Section 11.06		Reinstatement	43
ARTICLE XII SUBORDINATION OF DEBT SECURITIES AND GUARANTEE
Section 12.01		Applicability of Article; Agreement to Subordinate	43
Section 12.02		Liquidation, Dissolution, Bankruptcy	43
Section 12.03		Default on Senior Indebtedness	44
Section 12.04		Acceleration of Payment of Debt Securities	45
Section 12.05		When Distribution Must Be Paid Over	45
Section 12.06		Subrogation	45
Section 12.07		Relative Rights	45
Section 12.08		Subordination May Not Be Impaired by Partnership	45
Section 12.09		Rights of Trustee and Paying Agent	45
Section 12.10		Distribution or Notice to Representative	46
Section 12.11		Article XII Not to Prevent Defaults or Limit Right to Accelerate	46
Section 12.12		Trust Moneys Not Subordinated	46
Section 12.13		Trustee Entitled to Rely	46
Section 12.14		Trustee to Effectuate Subordination	46
Section 12.15		Trustee Not Fiduciary for Holders of Senior Indebtedness	47
Section 12.16		Reliance by Holders of Senior Indebtedness on Subordination Provisions	47
ARTICLE XIII MISCELLANEOUS PROVISIONS
Section 13.01		Successors and Assigns of Partnership Bound by Indenture	47
Section 13.02		Acts of Board, Committee or Officer of Successor Partnership Valid	47
Section 13.03		Required Notices or Demands	47
Section 13.04		Indenture and Debt Securities to Be Construed in Accordance with the Laws of the State of New York	48
Section 13.05		Officers' Certificate and Opinion of Counsel to Be Furnished upon Application or Demand by the Partnership	48
Section 13.06		Payments Due on Legal Holidays	48
Section 13.07		Provisions Required by TIA to Control	49
Section 13.08		Computation of Interest on Debt Securities	49
Section 13.09		Rules by Trustee, Paying Agent and Registrar	49
Section 13.10		No Recourse Against Others	49

iv

Section 13.11	Severability	49
Section 13.12	Effect of Headings	49
Section 13.13	Indenture May Be Executed in Counterparts	49
ARTICLE XIV GUARANTEE
Section 14.01	Unconditional Guarantee	49
Section 14.02	Execution and Delivery of Guarantee	51
Section 14.03	Limitation on Subsidiary Guarantors' Liability	51
Section 14.04	Release of Subsidiary Guarantors from Guarantee	52
Section 14.05	Subsidiary Guarantor Contribution	52
Notation of Guarantee	Annex A

v

        THIS INDENTURE dated as of [                        ] among MarkWest Energy Partners, L.P., a Delaware limited partnership, (the "Partnership"), any Subsidiary Guarantors (as defined herein party hereto and [                        ], a, as trustee (the "Trustee").

RECITALS OF THE COMPANY AND ANY SUBSIDIARY GUARANTORS

        The Partnership and any Subsidiary Guarantors have duly authorized the execution and delivery of this Indenture to provide for the issuance from time to time of the Partnership's debentures, notes, bonds or other evidences of indebtedness to be issued in one or more series unlimited as to principal amount (herein called the "Debt Securities"), which Debt Securities may be guaranteed by each of the Subsidiary Guarantors an may be subordinated in right of payment to Senior Indebtedness, as in this Indenture provided.

        All things necessary to make this Indenture a valid agreement of the Partnership and any Subsidiary Guarantors, in accordance with its terms, have been done.

NOW, THEREFORE, THIS INDENTURE WITNESSETH

        That in order to declare the terms and conditions upon which the Debt Securities are authenticated, issued and delivered, and in consideration of the premises, and of the purchase and acceptance of the Debt Securities by the Holders thereof, the Partnership, any Subsidiary Guarantor and the Trustee covenant and agree with each other, for the benefit of the respective Holders from time to time of the Debt Securities or any series thereof, as follows:

ARTICLE I

DEFINITIONS AND INCORPORATION BY REFERENCE

        Section 1.01 Definitions.

        "Affiliate" of any specified Person means any other Person directly or indirectly controlling or controlled by or under direct or indirect common control with such specified Person. For the purposes of this definition, "control" when used with respect to any specified Person means the power to direct the management and policies of such Person, directly or indirectly, whether through the ownership of voting securities, by contract or otherwise; and the terms "controlling" and "controlled" have meanings correlative to the foregoing. The Trustee may request and may conclusively rely upon an Officers' Certificate to determine whether any Person is an Affiliate of any specified Person.

        "Agent" means any Registrar or paying agent.

        "Bankruptcy Law" means Title 11, U.S. Code or any similar federal or state law for the relief of debtors.

        "Board of Directors" means the Board of Directors of the general partner of the Partnership or any authorized committee of the Board of Directors of the general partner of the Partnership or any directors and/or officers of the Partnership to whom such Board of Directors or such committee shall have duly delegated its authority to act hereunder. If the Partnership shall change its form of entity to other than a limited Partnership, the references to the Board of Directors of the general partner of the Partnership shall mean the Board of Directors (or other comparable governing body) of the general partner of the Partnership.

        "Business Day" means any day other than a Legal Holiday.

        "capital stock" of any Person means and includes any and all shares, rights to purchase, warrants or options (whether or not currently exercisable), participations or other equivalents of or interests in (however designated) the equity (which includes, but is not limited to, common stock, preferred stock

1

and Partnership and joint venture interests) of such Person (excluding any debt securities that are convertible into, or exchangeable for, such equity).

        "Custodian" means any receiver, trustee, assignee, liquidator or similar official under any Bankruptcy Law.

        "Debt" of any Person at any date means any obligation created or assumed by such Person for the repayment of borrowed money and any guarantee thereof.

        "Debt Security" or "Debt Securities" has the meaning stated in the first recital of this Indenture and more particularly means any debt security or debt securities, as the case may be of any series authenticated and delivered under this Indenture.

        "Default" means any event, act or condition that is, or after notice or the passage of time or both would be, an Event of Default.

        "Depositary" means, unless otherwise specified by the Partnership pursuant to either Section 2.03 or 2.15, with respect to Debt Securities of any series issuable or issued in whole or in part in the form of one or more Global Securities, The Depository Trust Partnership, New York, New York, or any successor thereto registered as a clearing agency under the Exchange Act or other applicable statute or regulations.

        "Designated Senior Indebtedness" means (i) any Senior Indebtedness which, at the date of determination, has an aggregate principal amount outstanding of, or under which, at the date of determination, the holders thereof are committed to lend up to, at least $100 million and (ii) any other Senior Indebtedness designated, as provided in Section 2.03, in respect of any series of Debt Securities.

        "Dollar" or "$" means such currency of the United States as at the time of payment is legal tender for the payment of public and private debts.

        "Exchange Act" means the Securities Exchange Act of 1934, as amended, and any successor statute.

        "Floating Rate Security" means a Debt Security that provides for the payment of interest at a variable rate determined periodically by reference to an interest rate index specified pursuant to Section 2.03.

        "GAAP" means generally accepted accounting principles in the United States, as in effect from time to time.

        "Global Security" means with respect to any series of Debt Securities issued hereunder, a Debt Security which is executed by the Partnership and authenticated and delivered by the Trustee to the Depositary or pursuant to the Depositary's instruction, all in accordance with this Indenture and any Indentures supplemental hereto, or resolution of the Board of Directors and set forth in an Officers' Certificate, which shall be registered in the name of the Depositary or its nominee and which shall represent, and shall be denominated in an amount equal to the aggregate principal amount of, all the Outstanding Debt Securities of such series or any portion thereof, in either case having the same terms, including, without limitation, the same original issue date, date or dates on which principal is due and interest rate or method of determining interest.

        "guarantee" means any obligation, contingent or otherwise, of any Person directly or indirectly guaranteeing any Debt or other obligation of any other Person and any obligation, direct or indirect, contingent or otherwise, of such Person (a) to purchase or pay (or advance or supply funds for the purchase or payment of) such Debt or other obligation of such other Person (whether arising by virtue of Partnership arrangements, or by agreement to keep-well, to purchase assets, goods, securities or services, to take-or-pay, or to maintain financial statement conditions or otherwise) or (b) entered into for purposes of assuring in any other manner the obligee of such Debt or other obligation of the

2

payment thereof or to protect such obligee against loss in respect thereof (in whole or in part); provided, however, that the term "guarantee" shall not include endorsements for collection or deposit in the ordinary course of business. The term "guarantee" used as a verb has a corresponding meaning.

        "Holder," "Holder of Debt Securities" or other similar terms means, a Person in whose name a Debt Security is registered in the Debt Security Register (as defined in Section 2.07(a)).

        "Indenture" means this instrument as originally executed, or, if amended or supplemented as herein provided, as so amended or supplemented and shall include the form and terms of particular series of Debt Securities as contemplated hereunder, whether or not a supplemental Indenture is entered into with respect thereto.

        "Legal Holiday" means a Saturday, a Sunday or a day on which banking institutions in the City of Houston, Texas, City of New York, New York or at a Place of Payment are authorized by law, regulation or executive order to remain closed. If a payment date is a Legal Holiday at a Place of Payment, payment may be made at that place on the next succeeding day that is not a Legal Holiday, and no interest shall accrue for the intervening period.

        "Lien" means, with respect to any asset, any mortgage, lien, security interest, pledge, charge or other encumbrance of any kind in respect of such asset, whether or not filed, recorded or otherwise perfected under applicable law.

        "Officer" means, with respect to a Person, the Chairman of the Board, the President, any Vice President, the Treasurer, any Assistant Treasurer, Controller, Secretary or any Assistant Secretary of such Person.

        "Officers' Certificate" means a certificate signed by two Officers of the Partnership, one of whom must be the Partnership's chief executive officer, chief financial officer or chief accounting officer (or if the Partnership shall change its form of entity to other than a limited Partnership, by Persons, officers, members, agents and others holding positions comparable to those of the foregoing nature, as applicable).

        "Opinion of Counsel" means a written opinion from legal counsel who is acceptable to the Trustee. The counsel may be an employee of or counsel to the Partnership or the Trustee.

        "Original Issue Discount Debt Security" means any Debt Security which provides for an amount less than the principal amount thereof to be due and payable upon a declaration of acceleration of the maturity thereof pursuant to Section 6.01.

        "Outstanding," when used with respect to any series of Debt Securities, means, as of the date of determination, all Debt Securities of that series theretofore authenticated and delivered under this Indenture, except:

        (a)   Debt Securities of that series theretofore canceled by the Trustee or delivered to the Trustee for cancellation;

        (b)   Debt Securities of that series for whose payment or redemption money in the necessary amount has been theretofore deposited with the Trustee or any paying agent (other than the Partnership) in trust or set aside and segregated in trust by the Partnership (if the Partnership shall act as its own paying agent) for the Holders of such Debt Securities; provided, that, if such Debt Securities are to be redeemed, notice of such redemption has been duly given pursuant to this Indenture or provision therefor satisfactory to the Trustee has been made; and

        (c)   Debt Securities of that series which have been paid pursuant to Section 2.09 or in exchange for or in lieu of which other Debt Securities have been authenticated and delivered pursuant to this Indenture, other than any such Debt Securities in respect of which there shall have been presented to

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the Trustee proof satisfactory to it that such Debt Securities are held by a bona fide purchaser in whose hands such Debt Securities are valid obligations of the Partnership;

provided, however, that in determining whether the Holders of the requisite principal amount of the Outstanding Debt Securities of any series have given any request, demand, authorization, direction, notice, consent or waiver hereunder, Debt Securities owned by the Partnership or any other obligor upon the Debt Securities or any Affiliate of the Partnership or of such other obligor shall be disregarded and deemed not to be Outstanding, except that, in determining whether the Trustee shall be protected in relying upon any such request, demand, authorization, direction, notice, consent or waiver, only Debt Securities which a Trust Officer actually knows to be so owned shall be so disregarded. Debt Securities so owned which have been pledged in good faith may be regarded as Outstanding if the pledgee establishes to the satisfaction of the Trustee the pledgee's right so to act with respect to such Debt Securities and that the pledgee is not the Partnership or any other obligor upon the Debt Securities or an Affiliate of the Partnership or of such other obligor. In determining whether the Holders of the requisite principal amount of Outstanding Debt Securities have given any request, demand, authorization, direction, notice, consent or waiver hereunder, the principal amount of an Original Issue Discount Debt Security that shall be deemed to be Outstanding for such purposes shall be the amount of the principal thereof that would be due and payable as of the date of such determination upon a declaration of acceleration of the maturity thereof pursuant to Section 6.01.

        "Partnership" means the Person named as the "Partnership" in the first paragraph of this instrument until a successor Person shall have become such pursuant to the applicable provisions of this Indenture, and thereafter "Partnership" shall mean such successor Person.

        "Partnership Order" means a written request or order signed in the name of the Partnership by the Chairman of the Board, the President or a Vice President of the Partnership, and by the Treasurer, an Assistant Treasurer, the Controller, an Assistant Controller, the Secretary or an Assistant Secretary of the Partnership, and delivered to the Trustee, or if the Partnership shall change its form of entity to other than a limited Partnership, by Persons or officers, members, agents and others holding positions comparable to those of the foregoing nature, as applicable.

        "Person" means any individual, corporation, Partnership, joint venture, limited liability company, incorporated or unincorporated association, joint-stock company, trust, unincorporated organization or government or other agency or political subdivision thereof or other entity of any kind.

        "Redemption Date," when used with respect to any Debt Security to be redeemed, means the date fixed for such redemption by or pursuant to this Indenture.

        "Representative" means the trustee, agent or representative (if any) for an issue of Senior Debt.

        "SEC" means the Securities and Exchange Commission.

        "Securities Act" means the Securities Act of 1933, as amended, and any successor statute.

        "Senior Indebtedness," unless otherwise provided with respect to the Debt Securities of a series as contemplated by Section 2.03, means (1) all Debt of the Subsidiary Guarantors or the Partnership, whether currently outstanding or hereafter issued, unless, by the terms of the instrument creating or evidencing such Debt, it is provided that such Debt is subordinate or not superior in right of payment to the Debt Securities, in the case of the Partnership, or the Guarantee, in the case of the Subsidiary Guarantors, or to other Debt which is pari passu with or subordinated to the Debt Securities, in the case of the Partnership, or the Guarantee, in the case of the Subsidiary Guarantors, and (2) any modifications, refunding, deferrals, renewals, or extensions of any such Debt or securities, notes or other evidence of Debt issued in exchange for such Debt; provided that in no event shall "Senior Indebtedness" include (a) Debt evidenced by the Debt Securities or any Guarantee, (b) Debt of any of the Subsidiary Guarantors or the Partnership owed or owing to any Subsidiary of the Partnership,

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(c) Debt of any of the Subsidiary Guarantors owed or owing to the Partnership, (d) Debt to trade creditors, (e) any liability for taxes owed or owing by the Subsidiary Guarantors or the Partnership or (f) Debt of any Subsidiary Guarantor in the event there is no series of Debt Securities Outstanding that is entitled to the benefits of a Guarantee.

        "Stated Maturity" means, with respect to any security, the date specified in such security as the fixed date on which the payment of principal of such security is due and payable, including pursuant to any mandatory redemption provision (but excluding any provision providing for the repurchase of such security at the option of the holder thereof upon the happening of any contingency beyond the control of the issuer unless such contingency has occurred).

        "Subsidiary" of any Person means any corporation, association or other business entity of which more than 50% of the total voting power of equity interests entitled, without regard to the occurrence of any contingency, to vote in the election of directors, managers, trustees or equivalent Persons thereof is at the time of determination owned or controlled, directly or indirectly, by such Person or one or more of the other Subsidiaries of such Person or combination thereof.

        "Subsidiary Guarantors" means any Subsidiary of the Partnership who may execute this Indenture, or a supplement hereto, for the purpose of providing a Guarantee of Debt Securities pursuant to this Indenture until a successor Person shall have become such pursuant to the applicable provisions of this Indenture, and thereafter "Subsidiary Guarantors" shall mean such successor Person.

        "TIA" means the Trust Indenture Act of 1939, as amended (15 U.S.C. "77aaa-77bbbb), as in effect on the date of this Indenture as originally executed and, to the extent required by law, as amended.

        "Trustee" initially means [                        ] and any other Person or Persons appointed as such from time to time pursuant to Section 7.08, and, subject to the provisions of Article VII, includes its or their successors and assigns. If at any time there is more than one such Person, "Trustee" as used with respect to the Debt Securities of any series shall mean the Trustee with respect to the Debt Securities of that series.

        "Trust Officer" means any officer or assistant officer of the Trustee assigned by the Trustee to administer its corporate trust matters.

        "United States" means the United States of America (including the States and the District of Columbia), its territories, its possessions and other areas subject to its jurisdiction.

        "U.S. Government Obligations" means direct obligations of the United States of America, obligations on which the payment of principal and interest is fully guaranteed by the United States of America or obligations or guarantees for the payment of which the full faith and credit of the United States of America is pledged.

        "Yield to Maturity" means the yield to maturity, calculated at the time of issuance of a series of Debt Securities, or, if applicable, at the most recent redetermination of interest on such series and calculated in accordance with accepted financial practice.

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        Section 1.02 Other Definitions.

Term	Defined in Section
"Debt Security Register"		2.07
"Defaulted Interest"		2.17
"Event of Default"		6.01
"Funding Guarantor"		14.05
"Guarantee"		14.01
"Place of Payment"		2.03
"Registrar"		2.07
"Successor Partnership"		10.01

        Section 1.03 Incorporation by Reference of Trust Indenture Act. Whenever this Indenture refers to a provision of the TIA, the provision is incorporated by reference in and made a part of this Indenture.

        All terms used in this Indenture that are defined by the TIA, defined by TIA reference to another statute or defined by SEC rule under the TIA have the meanings so assigned to them.

        Section 1.04 Rules of Construction. Unless the context otherwise requires:

        (a)   a term has the meaning assigned to it;

        (b)   an accounting term not otherwise defined has the meaning assigned to it in accordance with GAAP;

        (c)   "or" is not exclusive;

        (d)   words in the singular include the plural, and in the plural include the singular;

        (e)   provisions apply to successive events and transactions;

        (f)    if the applicable series of Debt Securities are subordinated pursuant to Article XII, unsecured Debt shall not be deemed to be subordinate or junior to secured Debt merely by virtue of its nature as unsecured Debt; and

        (g)   the principal amount of any noninterest bearing or other discount security at any date shall be the principal amount thereof that would be shown on a balance sheet of the issuer dated such date prepared in accordance with GAAP.

ARTICLE II

DEBT SECURITIES

        Section 2.01 Forms Generally. The Debt Securities of each series shall be in substantially the form established without the approval of any Holder by or pursuant to a resolution of the Board of Directors or in one or more Indentures supplemental hereto, in each case with such appropriate insertions, omissions, substitutions and other variations as are required or permitted by this Indenture, and may have such letters, numbers or other marks of identification and such legends or endorsements placed thereon as the Partnership may deem appropriate (and, if not contained in a supplemental Indenture entered into in accordance with Article IX, as are not prohibited by the provisions of this Indenture) or as may be required or appropriate to comply with any law or with any rules made pursuant thereto or with any rules of any securities exchange on which such series of Debt Securities may be listed, or to conform to general usage, or as may, consistently herewith, be determined by the officers executing such Debt Securities as evidenced by their execution of the Debt Securities.

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        The definitive Debt Securities of each series shall be printed, lithographed or engraved on steel engraved borders or may be produced in any other manner, all as determined by the officers executing such Debt Securities, as evidenced by their execution of such Debt Securities.

        Section 2.02 Form of Trustee's Certificate of Authentication. The Trustee's certificate of authentication on all Debt Securities authenticated by the Trustee shall be in substantially the following form:

TRUSTEE'S CERTIFICATE OF AUTHENTICATION

        This is one of the Debt Securities of the series designated therein referred to in the within-mentioned Indenture.

[			],
	As Trustee
	By:
		Authorized Signatory

        Section 2.03 Principal Amount; Issuable in Series. The aggregate principal amount of Debt Securities which may be issued, executed, authenticated, delivered and outstanding under this Indenture is unlimited.

        The Debt Securities may be issued in one or more series in fully registered form. There shall be established, without the approval of any Holders, in or pursuant to a resolution of the Board of Directors and set forth in an Officers' Certificate, or established in one or more Indentures supplemental hereto, prior to the issuance of Debt Securities of any series any or all of the following:

        (a)   the title of the Debt Securities of the series (which shall distinguish the Debt Securities of the series from all other Debt Securities);

        (b)   any limit upon the aggregate principal amount of the Debt Securities of the series which may be authenticated and delivered under this Indenture (except for Debt Securities authenticated and delivered upon registration of transfer of, or in exchange for, or in lieu of, other Debt Securities of the series pursuant to this Article II);

        (c)   the date or dates on which the principal of and premium, if any, on the Debt Securities of the series are payable;

        (d)   the rate or rates (which may be fixed or variable) at which the Debt Securities of the series shall bear interest, if any, or the method of determining such rate or rates, the date or dates from which such interest shall accrue, the interest payment dates on which such interest shall be payable, or the method by which such date will be determined, the record dates for the determination of Holders thereof to whom such interest is payable; and the basis upon which interest will be calculated if other than that of a 360-day year of twelve thirty-day months;

        (e)   the place or places, if any, in addition to or instead of the corporate trust office of the Trustee, where the principal of, and premium, if any, and interest on, Debt Securities of the series shall be payable ("Place of Payment");

        (f)    the price or prices at which, the period or periods within which and the terms and conditions upon which Debt Securities of the series may be redeemed, in whole or in part, at the option of the Partnership or otherwise;

        (g)   whether Debt Securities of the series are entitled to the benefits of any Guarantee of any Subsidiary Guarantors pursuant to this Indenture;

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        (h)   the obligation, if any, of the Partnership to redeem, purchase or repay Debt Securities of the series pursuant to any sinking fund or analogous provisions or at the option of a Holder thereof, and the price or prices at which and the period or periods within which and the terms and conditions upon which Debt Securities of the series shall be redeemed, purchased or repaid, in whole or in part, pursuant to such obligations;

        (i)    the terms, if any, upon which the Debt Securities of the series may be convertible into or exchanged for capital stock (which may be represented by depositary shares), other Debt Securities or warrants for capital stock or Debt or other securities of any kind of the Partnership or any other obligor and the terms and conditions upon which such conversion or exchange shall be effected, including the initial conversion or exchange price or rate, the conversion or exchange period and any other provision in addition to or in lieu of those described herein;

        (j)    if other than denominations of $1,000 and any integral multiple thereof, the denominations in which Debt Securities of the series shall be issuable;

        (k)   if the amount of principal of or any premium or interest on Debt Securities of the series may be determined with reference to an index or pursuant to a formula, the manner in which such amounts will be determined;

        (l)    if the principal amount payable at the Stated Maturity of Debt Securities of the series will not be determinable as of any one or more dates prior to such Stated Maturity, the amount which will be deemed to be such principal amount as of any such date for any purpose, including the principal amount thereof which will be due and payable upon any maturity other than the Stated Maturity or which will be deemed to be Outstanding as of any such date (or, in any such case, the manner in which such deemed principal amount is to be determined);

        (m)  any changes or additions to Article XI, including the addition of additional covenants that may be subject to the covenant defeasance option pursuant to Section 11.02(b);

        (n)   if other than the principal amount thereof, the portion of the principal amount of Debt Securities of the series which shall be payable upon declaration of acceleration of the maturity thereof pursuant to Section 6.01 or provable in bankruptcy pursuant to Section 6.02;

        (o)   the terms, if any, of the transfer, mortgage, pledge or assignment as security for the Debt Securities of the series of any properties, assets, moneys, proceeds, securities or other collateral, including whether certain provisions of the TIA are applicable and any corresponding changes to provisions of this Indenture as currently in effect;

        (p)   any addition to or change in the Events of Default with respect to the Debt Securities of the series and any change in the right of the Trustee or the Holders to declare the principal of, and premium and interest on, such Debt Securities due and payable;

        (q)   if the Debt Securities of the series shall be issued in whole or in part in the form of a Global Security or Securities, the terms and conditions, if any, upon which such Global Security or Securities may be exchanged in whole or in part for other individual Debt Securities in definitive registered form; and the Depositary for such Global Security or Securities and the form of any legend or legends to be borne by any such Global Security or Securities in addition to or in lieu of the legend referred to in Section 2.15(a);

        (r)   any trustees, authenticating or paying agents, transfer agents or registrars;

        (s)   the applicability of, and any addition to or change in the covenants and definitions currently set forth in this Indenture or in the terms currently set forth in Article X, including conditioning any merger, conveyance, transfer or lease permitted by Article X upon the satisfaction of any Debt coverage standard by the Partnership and Successor Partnership (as defined in Article X);

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        (t)    the subordination, if any, of the Debt Securities of the series pursuant to Article XII and any changes or additions to Article XII or designation of any Designated Senior Indebtedness;

        (u)   with regard to Debt Securities of the series that do not bear interest, the dates for certain required reports to the Trustee; and

        (v)   any other terms of the Debt Securities of the series (which terms shall not be prohibited by the provisions of this Indenture).

        All Debt Securities of any one series shall be substantially identical except as to denomination and except as may otherwise be provided in or pursuant to such resolution of the Board of Directors and as set forth in such Officers' Certificate or in any such Indenture supplemental hereto.

        Section 2.04 Execution of Debt Securities. The Debt Securities shall be signed on behalf of the Partnership by the Chairman of the Board, the President or a Vice President of the Partnership and, if the seal of the Partnership is reproduced thereon, it shall be attested by its Secretary, an Assistant Secretary, a Treasurer or an Assistant Treasurer. Such signatures upon the Debt Securities may be the manual or facsimile signatures of the present or any future such authorized officers and may be imprinted or otherwise reproduced on the Debt Securities. The seal of the Partnership , if any, may be in the form of a facsimile thereof and may be impressed, affixed, imprinted or otherwise reproduced on the Debt Securities.

        Only such Debt Securities as shall bear thereon a certificate of authentication substantially in the form hereinbefore recited, signed manually by the Trustee, shall be entitled to the benefits of this Indenture or be valid or obligatory for any purpose. Such certificate by the Trustee upon any Debt Security executed by the Partnership on behalf of the Partnership shall be conclusive evidence that the Debt Security so authenticated has been duly authenticated and delivered hereunder.

        In case any officer of the Partnership who shall have signed any of the Debt Securities shall cease to be such officer before the Debt Securities so signed shall have been authenticated and delivered by the Trustee, or disposed of by the Partnership, such Debt Securities nevertheless may be authenticated and delivered or disposed of as though the Person who signed such Debt Securities had not ceased to be such officer of the Partnership ; and any Debt Security may be signed on behalf of the Partnership by such Persons as, at the actual date of the execution of such Debt Security, shall be the proper officers of the Partnership , although at the date of such Debt Security or of the execution of this Indenture any such Person was not such officer.

        Section 2.05 Authentication and Delivery of Debt Securities. At any time and from time to time after the execution and delivery of this Indenture, the Partnership may deliver to the Trustee for authentication Debt Securities of any series executed by the Partnership, and the Trustee shall thereupon authenticate and deliver said Debt Securities to or upon a Partnership Order. In authenticating such Debt Securities, and accepting the additional responsibilities under this Indenture in relation to such Debt Securities, the Trustee shall be entitled to receive, and (subject to Section 7.01) shall be fully protected in relying upon:

        (a)   a copy of any resolution or resolutions of the Board of Directors, certified by the Secretary or Assistant Secretary of the Partnership, authorizing the terms of issuance of any series of Debt Securities;

        (b)   an executed supplemental Indenture, if any;

        (c)   an Officers' Certificate; and

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        (d)   an Opinion of Counsel prepared in accordance with Section 13.05 which shall also state:

        (i)    that the form of such Debt Securities has been established by or pursuant to a resolution of the Board of Directors or by a supplemental Indenture as permitted by Section 2.01 in conformity with the provisions of this Indenture;

        (ii)   that the terms of such Debt Securities have been established by or pursuant to a resolution of the Board of Directors or by a supplemental Indenture as permitted by Section 2.03 in conformity with the provisions of this Indenture;

        (iii)  that such Debt Securities, when authenticated and delivered by the Trustee and issued by the Partnership in the manner and subject to any conditions specified in such Opinion of Counsel, will constitute valid and legally binding obligations of the Partnership, enforceable in accordance with their terms except as the enforceability thereof may be limited by bankruptcy, insolvency or similar laws affecting the enforcement of creditors' rights generally and rights of acceleration and the availability of equitable remedies may be limited by equitable principles of general applicability;

        (iv)  that the Partnership has the Partnership power to issue such Debt Securities and has duly taken all necessary Partnership action with respect to such issuance;

        (v)   that the issuance of such Debt Securities will not contravene the organizational documents of the Partnership or result in any material violation of any of the terms or provisions of any law or regulation or of any material indenture, mortgage or other agreement known to such counsel by which the Partnership is bound;

        (vi)  that authentication and delivery of such Debt Securities and the execution and delivery of any supplemental Indenture will not violate the terms of this Indenture; and

        (vii) such other matters as the Trustee may reasonably request.

        Such Opinion of Counsel need express no opinion as to whether a court in the United States would render a money judgment in a currency other than that of the United States.

        The Trustee shall have the right to decline to authenticate and deliver any Debt Securities under this Section 2.05 if the Trustee, being advised by counsel, determines that such action may not lawfully be taken or if the Trustee in good faith by its board of directors or trustees, executive committee or a trust committee of directors, trustees or Officers (or any combination thereof) shall determine that such action would expose the Trustee to personal liability to existing Holders.

        The Trustee may appoint an authenticating agent reasonably acceptable to the Partnership to authenticate Debt Securities of any series. Unless limited by the terms of such appointment, an authenticating agent may authenticate Debt Securities whenever the Trustee may do so. Each reference in this Indenture to authentication by the Trustee includes authentication by such agent. An authenticating agent has the same rights as any Registrar, paying agent or agent for service of notices and demands.

        Unless otherwise provided in the form of Debt Security for any series, each Debt Security shall be dated the date of its authentication.

        Section 2.06 Denomination of Debt Securities. Unless otherwise provided in the form of Debt Security for any series, the Debt Securities of each series shall be issuable only as fully registered Debt Securities in such Dollar denominations as shall be specified or contemplated by Section 2.03. In the absence of any such specification with respect to the Debt Securities of any series, the Debt Securities of such series shall be issuable in denominations of $1,000 and any integral multiple thereof.

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        Section 2.07 Registration of Transfer and Exchange.

        (a)   The Partnership shall keep or cause to be kept a register for each series of Debt Securities issued hereunder (hereinafter collectively referred to as the "Debt Security Register"), in which, subject to such reasonable regulations as it may prescribe, the Partnership shall provide for the registration of all Debt Securities and the transfer of Debt Securities as in this Article II provided. At all reasonable times the Debt Security Register shall be open for inspection by the Trustee. Subject to Section 2.15, upon due presentment for registration of transfer of any Debt Security at any office or agency to be maintained by the Partnership in accordance with the provisions of Section 4.02, the Partnership shall execute and the Trustee shall authenticate and deliver in the name of the transferee or transferees a new Debt Security or Debt Securities of authorized denominations for a like aggregate principal amount. In no event may Debt Securities be issued as, exchanged for, bearer securities.

        Unless and until otherwise determined by the Partnership by resolution of the Board of Directors, the Debt Security Register shall be kept at the principal corporate trust office of the Trustee and, for this purpose, the Trustee shall be designated "Registrar."

        Debt Securities of any series (other than a Global Security, except as set forth below) may be exchanged for a like aggregate principal amount of Debt Securities of the same series of other authorized denominations. Subject to Section 2.15, Debt Securities to be exchanged shall be surrendered at the office or agency to be maintained by the Partnership as provided in Section 4.02, and the Partnership shall execute and the Trustee shall authenticate and deliver in exchange therefor the Debt Security or Debt Securities which the Holder making the exchange shall be entitled to receive.

        (b)   All Debt Securities presented or surrendered for registration of transfer, exchange or payment shall (if so required by the Partnership, the Trustee or the Registrar) be duly endorsed or be accompanied by a written instrument or instruments of transfer, in form satisfactory to the Partnership, the Trustee and the Registrar, duly executed by the Holder or his attorney duly authorized in writing.

        All Debt Securities issued in exchange for or upon transfer of Debt Securities shall be the valid obligations of the Partnership, evidencing the same debt, and entitled to the same benefits under this Indenture as the Debt Securities surrendered for such exchange or transfer.

        No service charge shall be made for any exchange or registration of transfer of Debt Securities (except as provided by Section 2.09), but the Partnership may require payment of a sum sufficient to cover any tax, fee, assessment or other governmental charge that may be imposed in relation thereto, other than those expressly provided in this Indenture to be made at the Partnership's own expense or without expense or without charge to the Holders.

        The Partnership shall not be required (i) to issue, register the transfer of or exchange any Debt Securities for a period of 15 days next preceding any mailing of notice of redemption of Debt Securities of such series or (ii) to register the transfer of or exchange any Debt Securities selected, called or being called for redemption.

        Prior to the due presentation for registration of transfer of any Debt Security, the Partnership, the Subsidiary Guarantors, the Trustee, any paying agent or any Registrar may deem and treat the Person in whose name a Debt Security is registered as the absolute owner of such Debt Security for the purpose of receiving payment of or on account of the principal of, and premium, if any, and (subject to Section 2.12) interest on, such Debt Security and for all other purposes whatsoever, whether or not such Debt Security is overdue, and none of the Partnership, the Subsidiary Guarantors, the Trustee, any paying agent or any Registrar shall be affected by notice to the contrary.

        None of the Partnership, the Subsidiary Guarantors, the Trustee, any agent of the Trustee, any paying agent or any Registrar will have any responsibility or liability for any aspect of the records

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relating to, or payments made on account of, beneficial ownership interests of a Global Security or for maintaining, supervising or reviewing any records relating to such beneficial ownership interests.

        Section 2.08 Temporary Debt Securities. Pending the preparation of definitive Debt Securities of any series, the Partnership may execute and the Trustee shall authenticate and deliver temporary Debt Securities (printed, lithographed, photocopied, typewritten or otherwise produced) of any authorized denomination, and substantially in the form of the definitive Debt Securities in lieu of which they are issued, in registered form with such omissions, insertions and variations as may be appropriate for temporary Debt Securities, all as may be determined by the Partnership with the concurrence of the Trustee. Temporary Debt Securities may contain such reference to any provisions of this Indenture as may be appropriate. Every temporary Debt Security shall be executed by the Partnership and be authenticated by the Trustee upon the same conditions and in substantially the same manner, and with like effect, as the definitive Debt Securities.

        If temporary Debt Securities of any series are issued, the Partnership will cause definitive Debt Securities of such series to be prepared without unreasonable delay. After the preparation of definitive Debt Securities of such series, the temporary Debt Securities of such series shall be exchangeable for definitive Debt Securities of such series upon surrender of the temporary Debt Securities of such series at the office or agency of the Partnership at a Place of Payment for such series, without charge to the Holder thereof, except as provided in Section 2.07 in connection with a transfer. Upon surrender for cancellation of any one or more temporary Debt Securities of any series, the Partnership shall execute and the Trustee shall authenticate and deliver in exchange therefor a like principal amount of definitive Debt Securities of the same series of authorized denominations and of like tenor. Until so exchanged, temporary Debt Securities of any series shall in all respects be entitled to the same benefits under this Indenture as definitive Debt Securities of such series.

        Upon any exchange of a portion of a temporary Global Security for a definitive Global Security or for the individual Debt Securities represented thereby pursuant to Section 2.07 or this Section 2.08, the temporary Global Security shall be endorsed by the Trustee to reflect the reduction of the principal amount evidenced thereby, whereupon the principal amount of such temporary Global Security shall be reduced for all purposes by the amount to be exchanged and endorsed.

        Section 2.09 Mutilated, Destroyed, Lost or Stolen Debt Securities. If (a) any mutilated Debt Security is surrendered to the Trustee at its corporate trust office or (b) the Partnership and the Trustee receive evidence to their satisfaction of the destruction, loss or theft of any Debt Security, and there is delivered to the Partnership and the Trustee such security or indemnity as may be required by them to save each of them and any paying agent harmless, and neither the Partnership nor the Trustee receives notice that such Debt Security has been acquired by a bona fide purchaser, then the Partnership shall execute and, upon a Partnership Order, the Trustee shall authenticate and deliver, in exchange for or in lieu of any such mutilated, destroyed, lost or stolen Debt Security, a new Debt Security of the same series of like tenor, form, terms and principal amount, bearing a number not contemporaneously Outstanding. Upon the issuance of any substituted Debt Security, the Partnership or the Trustee may require the payment of a sum sufficient to cover any tax, fee, assessment or other governmental charge that may be imposed in relation thereto and any other expenses connected therewith. In case any Debt Security which has matured or is about to mature or which has been called for redemption shall become mutilated or be destroyed, lost or stolen, the Partnership may, instead of issuing a substituted Debt Security, pay or authorize the payment of the same (without surrender thereof except in the case of a mutilated Debt Security) if the applicant for such payment shall furnish the Partnership and the Trustee with such security or indemnity as either may require to save it harmless from all risk, however remote, and, in case of destruction, loss or theft, evidence to the satisfaction of the Partnership and the Trustee of the destruction, loss or theft of such Debt Security and of the ownership thereof.

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        Every substituted Debt Security of any series issued pursuant to the provisions of this Section 2.09 by virtue of the fact that any Debt Security is destroyed, lost or stolen shall constitute an original additional contractual obligation of the Partnership, whether or not the destroyed, lost or stolen Debt Security shall be found at any time, and shall be entitled to all the benefits of this Indenture equally and proportionately with any and all other Debt Securities of that series duly issued hereunder. All Debt Securities shall be held and owned upon the express condition that the foregoing provisions are exclusive with respect to the replacement or payment of mutilated, destroyed, lost or stolen Debt Securities, and shall preclude any and all other rights or remedies, notwithstanding any law or statute existing or hereafter enacted to the contrary with respect to the replacement or payment of negotiable instruments or other securities without their surrender.

        Section 2.10 Cancellation of Surrendered Debt Securities. All Debt Securities surrendered for payment, redemption, registration of transfer or exchange shall, if surrendered to the Partnership or any paying agent or a Registrar, be delivered to the Trustee for cancellation by it, or if surrendered to the Trustee, shall be canceled by it, and no Debt Securities shall be issued in lieu thereof except as expressly permitted by any of the provisions of this Indenture. All canceled Debt Securities held by the Trustee shall be destroyed (subject to the record retention requirements of the Exchange Act) and certification of their destruction delivered to the Partnership, unless otherwise directed. On request of the Partnership, the Trustee shall deliver to the Partnership canceled Debt Securities held by the Trustee. If the Partnership shall acquire any of the Debt Securities, however, such acquisition shall not operate as a redemption or satisfaction of the Debt represented thereby unless and until the same are delivered or surrendered to the Trustee for cancellation. The Partnership may not issue new Debt Securities to replace Debt Securities it has redeemed, paid or delivered to the Trustee for cancellation.

        Section 2.11 Provisions of the Indenture and Debt Securities for the Sole Benefit of the Parties and the Holders. Nothing in this Indenture or in the Debt Securities, expressed or implied, shall give or be construed to give to any Person, other than the parties hereto, the Holders or any Registrar or paying agent, any legal or equitable right, remedy or claim under or in respect of this Indenture, or under any covenant, condition or provision herein contained; all its covenants, conditions and provisions being for the sole benefit of the parties hereto, the Holders and any Registrar and paying agents.

        Section 2.12 Payment of Interest; Interest Rights Preserved.

        (a)   Interest on any Debt Security that is payable and is punctually paid or duly provided for on any interest payment date shall be paid to the Person in whose name such Debt Security is registered at the close of business on the regular record date for such interest notwithstanding the cancellation of such Debt Security upon any transfer or exchange subsequent to the regular record date. Payment of interest on Debt Securities shall be made at the corporate trust office of the Trustee (except as otherwise specified pursuant to Section 2.03), or at the option of the Partnership, by check mailed to the address of the Person entitled thereto as such address shall appear in the Debt Security Register or, if provided pursuant to Section 2.03 and in accordance with arrangements satisfactory to the Trustee, at the option of the Holder by wire transfer to an account designated by the Holder.

        (b)   Subject to the foregoing provisions of this Section 2.12 and Section 2.17, each Debt Security of a particular series delivered under this Indenture upon registration of transfer of or in exchange for or in lieu of any other Debt Security of the same series shall carry the rights to interest accrued and unpaid, and to accrue, which were carried by such other Debt Security.

        Section 2.13 Securities Denominated in Dollars. Except as otherwise specified pursuant to Section 2.03 for Debt Securities of any series, payment of the principal of, and premium, if any, and interest on, Debt Securities of such series will be made in Dollars.

        Section 2.14 Wire Transfers. Notwithstanding any other provision to the contrary in this Indenture, the Partnership may make any payment of moneys required to be deposited with the Trustee on

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account of principal of, or premium, if any, or interest on, the Debt Securities (whether pursuant to optional or mandatory redemption payments, interest payments or otherwise) by wire transfer in immediately available funds to an account designated by the Trustee before 11:00 a.m., New York City time, on the date such moneys are to be paid to the Holders of the Debt Securities in accordance with the terms hereof.

        Section 2.15 Securities Issuable in the Form of a Global Security.

        (a)   If the Partnership shall establish pursuant to Sections 2.01 and 2.03 that the Debt Securities of a particular series are to be issued in whole or in part in the form of one or more Global Securities, then the Partnership shall execute and the Trustee or its agent shall, in accordance with Section 2.05, authenticate and deliver, such Global Security or Securities, which shall represent, and shall be denominated in an amount equal to the aggregate principal amount of, the Outstanding Debt Securities of such series to be represented by such Global Security or Securities, or such portion thereof as the Partnership shall specify in an Officers' Certificate, shall be registered in the name of the Depositary for such Global Security or Securities or its nominee, shall be delivered by the Trustee or its agent to the Depositary or pursuant to the Depositary's instruction and shall bear a legend substantially to the following effect:

        "UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY, A NEW YORK CORPORATION ("DTC"), NEW YORK, NEW YORK, TO THE COMPANY OR ITS AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY CERTIFICATE ISSUED IS REGISTERED IN THE NAME OF CEDE & CO. OR SUCH OTHER NAME AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC (AND ANY PAYMENT IS MADE TO CEDE & CO., OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL INASMUCH AS THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

        TRANSFERS OF THIS GLOBAL SECURITY SHALL BE LIMITED TO TRANSFERS IN WHOLE, BUT NOT IN PART, TO NOMINEES OF DTC OR TO A SUCCESSOR THEREOF OR SUCH SUCCESSOR'S NOMINEE AND TRANSFERS OF PORTIONS OF THIS GLOBAL SECURITY SHALL BE LIMITED TO TRANSFERS MADE IN ACCORDANCE WITH THE RESTRICTIONS SET FORTH IN THE INDENTURE REFERRED TO HEREIN."

or such other legend as may then be required by the Depositary for such Global Security or Securities.

        (b)   Notwithstanding any other provision of this Section 2.15 or of Section 2.07 to the contrary, and subject to the provisions of paragraph (c) below, unless the terms of a Global Security expressly permit such Global Security to be exchanged in whole or in part for definitive Debt Securities in registered form, a Global Security may be transferred, in whole but not in part and in the manner provided in Section 2.07, only by the Depositary to a nominee of the Depositary for such Global Security, or by a nominee of the Depositary to the Depositary or another nominee of the Depositary, or by the Depositary or a nominee of the Depositary to a successor Depositary for such Global Security selected or approved by the Partnership, or to a nominee of such successor Depositary.

        (c)   (i)    If at any time the Depositary for a Global Security or Securities notifies the Partnership that it is unwilling or unable to continue as Depositary for such Global Security or Securities or if at any time the Depositary for the Debt Securities for such series shall no longer be eligible or in good standing under the Exchange Act or other applicable statute, rule or regulation, the Partnership shall appoint a successor Depositary with respect to such Global Security or Securities. If a successor Depositary for such Global Security or Securities is not appointed by the Partnership within 90 days after the Partnership receives such notice or becomes aware of such ineligibility, the

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Partnership shall execute, and the Trustee or its agent, upon receipt of a Partnership Order for the authentication and delivery of such individual Debt Securities of such series in exchange for such Global Security or Securities, will authenticate and deliver, individual Debt Securities of such series of like tenor and terms in definitive form in an aggregate principal amount equal to the principal amount of the Global Security or Securities in exchange for such Global Security or Securities.

        (ii)   If an Event of Default occurs and the Depositary for a Global Security or Securities notifies the Trustee of its decision to require that the Debt Securities of any series or portion thereof issued or issuable in the form of one or more Global Securities shall no longer be represented by such Global Security or Securities, the Partnership shall appoint a successor Depositary with respect to such Global Security or Securities. In such event the Partnership will execute, and the Trustee, upon receipt of a Partnership Order for the authentication and delivery of individual Debt Securities of such series in exchange in whole or in part for such Global Security or Securities, will authenticate and deliver individual Debt Securities of such series of like tenor and terms in definitive form in an aggregate principal amount equal to the principal amount of such series or portion thereof in exchange for such Global Security or Securities.

        (iii)  If specified by the Partnership pursuant to Sections 2.01 and 2.03 with respect to Debt Securities issued or issuable in the form of a Global Security, the Depositary for such Global Security may surrender such Global Security in exchange in whole or in part for individual Debt Securities of such series of like tenor and terms in definitive form on such terms as are acceptable to the Partnership, the Trustee and such Depositary. Thereupon the Partnership shall execute, and the Trustee or its agent upon receipt of a Partnership Order for the authentication and delivery of definitive Debt Securities of such series shall authenticate and deliver, without service charge, to each Person specified by such Depositary a new Debt Security or Securities of the same series of like tenor and terms and of any authorized denomination as requested by such Person in aggregate principal amount equal to and in exchange for such Person's beneficial interest in the Global Security; and to such Depositary a new Global Security of like tenor and terms and in an authorized denomination equal to the difference, if any, between the principal amount of the surrendered Global Security and the aggregate principal amount of Debt Securities delivered to Holders thereof.

        (iv)  In any exchange provided for in any of the preceding three paragraphs, the Partnership will execute and the Trustee or its agent will authenticate and deliver individual Debt Securities. Upon the exchange of the entire principal amount of a Global Security for individual Debt Securities, such Global Security shall be canceled by the Trustee or its agent. Except as provided in the preceding paragraph, Debt Securities issued in exchange for a Global Security pursuant to this Section 2.15 shall be registered in such names and in such authorized denominations as the Depositary for such Global Security, pursuant to instructions from its direct or indirect participants or otherwise, shall instruct the Trustee or the Registrar. The Trustee or the Registrar shall deliver such Debt Securities to the Persons in whose names such Debt Securities are so registered.

        (v)   Payments in respect of the principal of and interest on any Debt Securities registered in the name of the Depositary or its nominee will be payable to the Depositary or such nominee in its capacity as the registered owner of such Global Security. The Partnership, any Subsidiary Guarantors and the Trustee may treat the Person in whose name the Debt Securities, including the Global Security, are registered as the owner thereof for the purpose of receiving such payments and for any and all other purposes whatsoever. None of the Partnership, any Subsidiary Guarantors, the Trustee, any Registrar, the paying agent or any agent of the Partnership, any Subsidiary Guarantors or the Trustee will have any responsibility or liability for any aspect of the records relating to or payments made on account of the beneficial ownership interests of the Global Security by the Depositary or its nominee or any of the Depositary's direct or indirect participants, or for maintaining, supervising or reviewing any records of the Depositary, its

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nominee or any of its direct or indirect participants relating to the beneficial ownership interests of the Global Security, the payments to the beneficial owners of the Global Security of amounts paid to the Depositary or its nominee, or any other matter relating to the actions and practices of the Depositary, its nominee or any of its direct or indirect participants. None of the Partnership, any Subsidiary Guarantors, the Trustee or any such agent will be liable for any delay by the Depositary, its nominee, or any of its direct or indirect participants in identifying the beneficial owners of the Debt Securities, and the Partnership, any Subsidiary Guarantors and the Trustee may conclusively rely on, and will be protected in relying on, instructions from the Depositary or its nominee for all purposes (including with respect to the registration and delivery, and the respective principal amounts, of the Debt Securities to be issued).

        Section 2.16 Medium Term Securities. Notwithstanding any contrary provision herein, if all Debt Securities of a series are not to be originally issued at one time, it shall not be necessary for the Partnership to deliver to the Trustee an Officers' Certificate, resolutions of the Board of Directors, supplemental Indenture, Opinion of Counsel or written order or any other document otherwise required pursuant to Section 2.01, 2.03, 2.05 or 13.05 at or prior to the time of authentication of each Debt Security of such series if such documents are delivered to the Trustee or its agent at or prior to the authentication upon original issuance of the first such Debt Security of such series to be issued; provided, that any subsequent request by the Partnership to the Trustee to authenticate Debt Securities of such series upon original issuance shall constitute a representation and warranty by the Partnership that, as of the date of such request, the statements made in the Officers' Certificate delivered pursuant to Section 2.05 or 13.05 shall be true and correct as if made on such date and that the Opinion of Counsel delivered at or prior to such time of authentication of an original issuance of Debt Securities shall specifically state that it shall relate to all subsequent issuances of Debt Securities of such series that are identical to the Debt Securities issued in the first issuance of Debt Securities of such series.

        A Partnership Order delivered by the Partnership to the Trustee in the circumstances set forth in the preceding paragraph, may provide that Debt Securities which are the subject thereof will be authenticated and delivered by the Trustee or its agent on original issue from time to time upon the telephonic or written order of Persons designated in such written order (any such telephonic instructions to be promptly confirmed in writing by such Person) and that such Persons are authorized to determine, consistent with the Officers' Certificate, supplemental Indenture or resolution of the Board of Directors relating to such written order, such terms and conditions of such Debt Securities as are specified in such Officers' Certificate, supplemental Indenture or such resolution.

        Section 2.17 Defaulted Interest. Any interest on any Debt Security of a particular series which is payable, but is not punctually paid or duly provided for, on the dates and in the manner provided in the Debt Securities of such series and in this Indenture (herein called "Defaulted Interest") shall forthwith cease to be payable to the Holder thereof on the relevant record date by virtue of having been such Holder, and such Defaulted Interest may be paid by the Partnership, at its election in each case, as provided in clause (i) or (ii) below:

        (i)    The Partnership may elect to make payment of any Defaulted Interest to the Persons in whose names the Debt Securities of such series are registered at the close of business on a special record date for the payment of such Defaulted Interest, which shall be fixed in the following manner. The Partnership shall notify the Trustee in writing of the amount of Defaulted Interest proposed to be paid on each such Debt Security of such series and the date of the proposed payment, and at the same time the Partnership shall deposit with the Trustee an amount of money equal to the aggregate amount proposed to be paid in respect of such Defaulted Interest or shall make arrangements satisfactory to the Trustee for such deposit prior to the date of the proposed payment, such money when deposited to be held in trust for the benefit of the Persons entitled to such Defaulted Interest as in this clause provided. Thereupon the Trustee shall fix a special record date for the payment of such Defaulted Interest which shall be not more than 15 days and not less

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than 10 days prior to the date of the proposed payment and not less than 10 days after the receipt by the Trustee of the notice of the proposed payment. The Trustee shall promptly notify the Partnership of such special record date and, in the name and at the expense of the Partnership, shall cause notice of the proposed payment of such Defaulted Interest and the special record date therefor to be mailed, first class postage pre-paid, to each Holder thereof at its address as it appears in the Debt Security Register, not less than 10 days prior to such special record date. Notice of the proposed payment of such Defaulted Interest and the special record date therefor having been so mailed, such Defaulted Interest shall be paid to the Persons in whose names the Debt Securities of such series are registered at the close of business on such special record date.

        (ii)   The Partnership may make payment of any Defaulted Interest on the Debt Securities of such series in any other lawful manner not inconsistent with the requirements of any securities exchange on which the Debt Securities of such series may be listed, and upon such notice as may be required by such exchange, if, after notice given by the Partnership to the Trustee of the proposed payment pursuant to this clause, such manner of payment shall be deemed practicable by the Trustee.

        Section 2.18 CUSIP Numbers. The Partnership in issuing the Debt Securities may use "CUSIP" numbers (if then generally in use), and, if so, the Trustee shall use "CUSIP" numbers in notices of redemption as a convenience to Holders; provided that any such notice may state that no representation is made as to the accuracy of such numbers either as printed on the Debt Securities or as contained in any notice of a redemption and that reliance may be placed only on the other identification numbers printed on the Debt Securities, and any such redemption shall not be affected by any defect in or omission of such numbers. The Partnership will promptly notify the Trustee in writing of any change in the "CUSIP" numbers.

ARTICLE III

REDEMPTION OF DEBT SECURITIES

        Section 3.01 Applicability of Article. The provisions of this Article shall be applicable to the Debt Securities of any series which are redeemable before their Stated Maturity except as otherwise specified as contemplated by Section 2.03 for Debt Securities of such series.

        Section 3.02 Notice of Redemption; Selection of Debt Securities. In case the Partnership shall desire to exercise the right to redeem all or, as the case may be, any part of the Debt Securities of any series in accordance with their terms, by resolution of the Board of Directors or a supplemental Indenture, the Partnership shall fix a date for redemption and shall give notice of such redemption at least 30 and not more than 60 days prior to the date fixed for redemption to the Holders of Debt Securities of such series so to be redeemed as a whole or in part, in the manner provided in Section 13.03. The notice if given in the manner herein provided shall be conclusively presumed to have been duly given, whether or not the Holder receives such notice. In any case, failure to give such notice or any defect in the notice to the Holder of any Debt Security of a series designated for redemption as a whole or in part shall not affect the validity of the proceedings for the redemption of any other Debt Security of such series.

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        Each such notice of redemption shall specify (i) the date fixed for redemption, (ii) the redemption price at which Debt Securities of such series are to be redeemed (or the method of calculating such redemption price), (iii) the Place or Places of Payment that payment will be made upon presentation and surrender of such Debt Securities, (iv) that any interest accrued to the date fixed for redemption will be paid as specified in said notice, (v) that the redemption is for a sinking fund payment (if applicable), (vi) that, unless otherwise specified in such notice, if the Partnership defaults in making such redemption payment or if the Debt Securities of that series are subordinated pursuant to the terms of Article XII, the paying agent is prohibited from making such payment pursuant to the terms of this Indenture, (vii) that on and after said date any interest thereon or on the portions thereof to be redeemed will cease to accrue, (viii) that in the case of Original Issue Discount Securities original issue discount accrued after the date fixed for redemption will cease to accrue, (ix) the terms of the Debt Securities of that series pursuant to which the Debt Securities of that series are being redeemed and (x) that no representation is made as to the correctness or accuracy of the CUSIP number, if any, listed in such notice or printed on the Debt Securities of that series. If less than all the Debt Securities of a series are to be redeemed the notice of redemption shall specify the certificate numbers of any Debt Securities of that series to be redeemed that are not in global form. In case any Debt Security of a series is to be redeemed in part only, the notice of redemption shall state the portion of the principal amount thereof to be redeemed and shall state that on and after the date fixed for redemption, upon surrender of such Debt Security, a new Debt Security or Debt Securities of that series in principal amount equal to the unredeemed portion thereof, will be issued.

        At least five days before the giving of any notice of redemption, unless the Trustee consents to a shorter period, the Partnership shall give written notice to the Trustee of the Redemption Date, the principal amount of Debt Securities to be redeemed and the series and terms of the Debt Securities pursuant to which such redemption will occur. Such notice shall be accompanied by an Officers' Certificate and an Opinion of Counsel from the Partnership to the effect that such redemption will comply with the conditions herein, and such notice may be revoked at any time prior to the giving of a notice of redemption to the Holders pursuant to this Section 3.02. If fewer than all the Debt Securities of a series are to be redeemed, the record date relating to such redemption shall be selected by the Partnership and given in writing to the Trustee, which record date shall be not less than three days after the date of notice to the Trustee.

        By 11 a.m., New York City time, on the Redemption Date for any Debt Securities, the Partnership shall deposit with the Trustee or with a paying agent (or, if the Partnership is acting as its own paying agent, segregate and hold in trust) an amount of money in Dollars (except as provided pursuant to Section 2.03) sufficient to pay the redemption price of such Debt Securities or any portions thereof that are to be redeemed on that date, together with any interest accrued to the Redemption Date.

        If less than all the Debt Securities of like tenor and terms of a series are to be redeemed (other than pursuant to mandatory sinking fund redemptions), the Trustee shall select, on a pro rata basis, by lot or by such other method as in its sole discretion it shall deem appropriate and fair, the Debt Securities of that series or portions thereof (in multiples of $1,000) to be redeemed. In any case where more than one Debt Security of such series is registered in the same name, the Trustee in its discretion may treat the aggregate principal amount so registered as if it were represented by one Debt Security of such series. The Trustee shall promptly notify the Partnership in writing of the Debt Securities selected for redemption and, in the case of any Debt Securities selected for partial redemption, the principal amount thereof to be redeemed. If any Debt Security called for redemption shall not be so paid upon surrender thereof on such Redemption Date, the principal, premium, if any, and interest shall bear interest until paid from the Redemption Date at the rate borne by the Debt Securities of that series. If less than all the Debt Securities of unlike tenor and terms of a series are to be redeemed, the particular Debt Securities to be redeemed shall be selected by the Partnership.

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Provisions of this Indenture that apply to Debt Securities called for redemption also apply to portions of Debt Securities called for redemption.

        Section 3.03 Payment of Debt Securities Called for Redemption. If notice of redemption has been given as provided in Section 3.02, the Debt Securities or portions of Debt Securities of the series with respect to which such notice has been given shall become due and payable on the date and at the Place or Places of Payment stated in such notice at the applicable redemption price, together with any interest accrued to the date fixed for redemption, and on and after said date (unless the Partnership shall default in the payment of such Debt Securities at the applicable redemption price, together with any interest accrued to said date) any interest on the Debt Securities or portions of Debt Securities of any series so called for redemption shall cease to accrue, and any original issue discount in the case of Original Issue Discount Securities shall cease to accrue. On presentation and surrender of such Debt Securities at the Place or Places of Payment in said notice specified, the said Debt Securities or the specified portions thereof shall be paid and redeemed by the Partnership at the applicable redemption price, together with any interest accrued thereon to the date fixed for redemption.

        Any Debt Security that is to be redeemed only in part shall be surrendered at the Place of Payment with, if the Partnership, the Registrar or the Trustee so requires, due endorsement by, or a written instrument of transfer in form satisfactory to the Partnership, the Registrar and the Trustee duly executed by, the Holder thereof or his attorney duly authorized in writing, and the Partnership shall execute, and the Trustee shall authenticate and deliver to the Holder of such Debt Security without service charge, a new Debt Security or Debt Securities of the same series, of like tenor and form, of any authorized denomination as requested by such Holder in aggregate principal amount equal to and in exchange for the unredeemed portion of the principal of the Debt Security so surrendered; except that if a Global Security is so surrendered, the Partnership shall execute, and the Trustee shall authenticate and deliver to the Depositary for such Global Security, without service charge, a new Global Security in a denomination equal to and in exchange for the unredeemed portion of the principal of the Global Security so surrendered. In the case of a Debt Security providing appropriate space for such notation, at the option of the Holder thereof, the Trustee, in lieu of delivering a new Debt Security or Debt Securities as aforesaid, may make a notation on such Debt Security of the payment of the redeemed portion thereof.

        Section 3.04 Mandatory and Optional Sinking Funds. The minimum amount of any sinking fund payment provided for by the terms of Debt Securities of any series, resolution of the Board of Directors or a supplemental Indenture is herein referred to as a "mandatory sinking fund payment," and any payment in excess of such minimum amount provided for by the terms of Debt Securities of any series, resolution of the Board of Directors or a supplemental Indenture is herein referred to as an "optional sinking fund payment."

        In lieu of making all or any part of any mandatory sinking fund payment with respect to any Debt Securities of a series in cash, the Partnership may at its option (a) deliver to the Trustee Debt Securities of that series theretofore purchased or otherwise acquired by the Partnership or (b) receive credit for the principal amount of Debt Securities of that series which have been redeemed either at the election of the Partnership pursuant to the terms of such Debt Securities or through the application of permitted optional sinking fund payments pursuant to the terms of such Debt Securities, resolution or supplemental Indenture; provided, that such Debt Securities have not been previously so credited. Such Debt Securities shall be received and credited for such purpose by the Trustee at the redemption price specified in such Debt Securities, resolution or supplemental Indenture for redemption through operation of the sinking fund and the amount of such mandatory sinking fund payment shall be reduced accordingly.

        Section 3.05 Redemption of Debt Securities for Sinking Fund. Not less than 60 days prior to each sinking fund payment date for any series of Debt Securities, the Partnership will deliver to the Trustee

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an Officers' Certificate specifying the amount of the next ensuing sinking fund payment for that series pursuant to the terms of that series, any resolution or supplemental Indenture, the portion thereof, if any, which is to be satisfied by payment of cash and the portion thereof, if any, which is to be satisfied by delivering and crediting Debt Securities of that series pursuant to this Section 3.05 (which Debt Securities, if not previously redeemed, will accompany such certificate) and whether the Partnership intends to exercise its right to make any permitted optional sinking fund payment with respect to such series. Such certificate shall also state that no Event of Default has occurred and is continuing with respect to such series. Such certificate shall be irrevocable and upon its delivery the Partnership shall be obligated to make the cash payment or payments therein referred to, if any, by 11 a.m., New York City time, on the next succeeding sinking fund payment date. Failure of the Partnership to deliver such certificate (or to deliver the Debt Securities specified in this paragraph) shall not constitute a Default, but such failure shall require that the sinking fund payment due on the next succeeding sinking fund payment date for that series shall be paid entirely in cash and shall be sufficient to redeem the principal amount of such Debt Securities subject to a mandatory sinking fund payment without the option to deliver or credit Debt Securities as provided in this Section 3.05 and without the right to make any optional sinking fund payment, if any, with respect to such series.

        Any sinking fund payment or payments (mandatory or optional) made in cash plus any unused balance of any preceding sinking fund payments made in cash which shall equal or exceed $100,000 (or a lesser sum if the Partnership shall so request) with respect to the Debt Securities of any particular series shall be applied by the Trustee on the sinking fund payment date on which such payment is made (or, if such payment is made before a sinking fund payment date, on the sinking fund payment date following the date of such payment) to the redemption of such Debt Securities at the redemption price specified in such Debt Securities, resolution or supplemental Indenture for operation of the sinking fund together with any accrued interest to the date fixed for redemption. Any sinking fund moneys not so applied or allocated by the Trustee to the redemption of Debt Securities shall be added to the next cash sinking fund payment received by the Trustee for such series and, together with such payment, shall be applied in accordance with the provisions of this Section 3.05. Any and all sinking fund moneys with respect to the Debt Securities of any particular series held by the Trustee on the last sinking fund payment date with respect to Debt Securities of such series and not held for the payment or redemption of particular Debt Securities shall be applied by the Trustee, together with other moneys, if necessary, to be deposited sufficient for the purpose, to the payment of the principal of the Debt Securities of that series at its Stated Maturity.

        The Trustee shall select the Debt Securities to be redeemed upon such sinking fund payment date in the manner specified in the last paragraph of Section 3.02 and the Partnership shall cause notice of the redemption thereof to be given in the manner provided in Section 3.02 except that the notice of redemption shall also state that the Debt Securities are being redeemed by operation of the sinking fund. Such notice having been duly given, the redemption of such Debt Securities shall be made upon the terms and in the manner stated in Section 3.03.

        The Trustee shall not redeem any Debt Securities of a series with sinking fund moneys or mail any notice of redemption of such Debt Securities by operation of the sinking fund for such series during the continuance of a Default in payment of interest on such Debt Securities or of any Event of Default (other than an Event of Default occurring as a consequence of this paragraph) with respect to such Debt Securities, except that if the notice of redemption of any such Debt Securities shall theretofore have been mailed in accordance with the provisions hereof, the Trustee shall redeem such Debt Securities if cash sufficient for that purpose shall be deposited with the Trustee for that purpose in accordance with the terms of this Article III. Except as aforesaid, any moneys in the sinking fund for such series at the time when any such Default or Event of Default shall occur and any moneys thereafter paid into such sinking fund shall, during the continuance of such Default or Event of Default, be held as security for the payment of such Debt Securities; provided, however, that in case

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such Default or Event of Default shall have been cured or waived as provided herein, such moneys shall thereafter be applied on the next sinking fund payment date for such Debt Securities on which such moneys may be applied pursuant to the provisions of this Section 3.05.

ARTICLE IV

PARTICULAR COVENANTS OF THE COMPANY

        Section 4.01 Payment of Principal of, and Premium, If Any, and Interest on, Debt Securities. The Partnership, for the benefit of each series of Debt Securities, will duly and punctually pay or cause to be paid the principal of, and premium, if any, and interest on, each of the Debt Securities at the place, at the respective times and in the manner provided herein or in the Debt Securities. Each installment of interest on any Debt Securities not in global form may at the Partnership's option be paid by mailing checks for such interest payable to the Person entitled thereto pursuant to Section 2.07(a) to the address of such Person as it appears on the Debt Security Register.

        Principal of and premium and interest on Debt Securities of any series shall be considered paid on the date due if, by 11 a.m., New York City time, on such date the Trustee or any paying agent holds in accordance with this Indenture money sufficient to pay all principal, premium and interest then due and, in the case of Debt Securities subordinated pursuant to the terms of Article XII, the Trustee or such paying agent, as the case may be, is not prohibited from paying such money to the Holders on that date pursuant to the terms of this Indenture.

        The Partnership shall pay interest on overdue principal or premium, if any, at the rate specified therefor in the Debt Securities, and it shall pay interest on overdue installments of interest at the same rate to the extent lawful.

        Section 4.02 Maintenance of Offices or Agencies for Registration of Transfer, Exchange and Payment of Debt Securities. The Partnership will maintain in each Place of Payment for any series of Debt Securities an office or agency where Debt Securities of such series may be presented or surrendered for payment, and it shall also maintain (in or outside such Place of Payment) an office or agency where Debt Securities of such series may be surrendered for transfer or exchange and where notices and demands to or upon the Partnership in respect of the Debt Securities of such series and this Indenture may be served. The Partnership will give prompt written notice to the Trustee of the location, and any change in the location, of such office or agency. If at any time the Partnership shall fail to maintain any such required office or agency or shall fail to furnish the Trustee with the address thereof, such presentations, surrenders, notices and demands may be made or served at the office of the Trustee where its corporate trust business is principally administered in the United States, and the Partnership hereby appoints the Trustee as its agent to receive all presentations, surrenders, notices and demands.

        The Partnership may also from time to time designate different or additional offices or agencies to be maintained for such purposes (in or outside of such Place of Payment), and may from time to time rescind any such designation; provided, however, that no such designation or rescission shall in any manner relieve the Partnership of its obligations described in the preceding paragraph. The Partnership will give prompt written notice to the Trustee of any such additional designation or rescission of designation and any change in the location of any such different or additional office or agency.

        Section 4.03 Appointment to Fill a Vacancy in the Office of Trustee. The Partnership, whenever necessary to avoid or fill a vacancy in the office of Trustee, will appoint, in the manner provided in Section 7.08, a Trustee, so that there shall at all times be a Trustee hereunder with respect to each series of Debt Securities.

        Section 4.04 Duties of Paying Agents, etc.

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        (a)   The Partnership shall cause each paying agent, if any, other than the Trustee, to execute and deliver to the Trustee an instrument in which such agent shall agree with the Trustee, subject to the provisions of this Section 4.04,

          (i)  that it will hold all sums held by it as such agent for the payment of the principal of, and premium, if any, or interest on, the Debt Securities of any series (whether such sums have been paid to it by the Partnership or by any other obligor on the Debt Securities of such series) in trust for the benefit of the Holders of the Debt Securities of such series;

         (ii)  that it will give the Trustee notice of any failure by the Partnership (or by any other obligor on the Debt Securities of such series) to make any payment of the principal of, and premium, if any, or interest on, the Debt Securities of such series when the same shall be due and payable; and

        (iii)  that it will at any time during the continuance of an Event of Default, upon the written request of the Trustee, forthwith pay to the Trustee all sums so held by it as such agent.

        (b)   If the Partnership shall act as its own paying agent, it will, on or before each due date of the principal of, and premium, if any, or interest on, the Debt Securities of any series, set aside, segregate and hold in trust for the benefit of the Holders of the Debt Securities of such series a sum sufficient to pay such principal, premium, if any, or interest so becoming due. The Partnership will promptly notify the Trustee of any failure by the Partnership to take such action or the failure by any other obligor on such Debt Securities to make any payment of the principal of, and premium, if any, or interest on, such Debt Securities when the same shall be due and payable.

        (c)   Anything in this Section 4.04 to the contrary notwithstanding, the Partnership may, at any time, for the purpose of obtaining a satisfaction and discharge of this Indenture, or for any other reason, pay or cause to be paid to the Trustee all sums held in trust by it or any paying agent, as required by this Section 4.04, such sums to be held by the Trustee upon the same trusts as those upon which such sums were held by the Partnership or such paying agent.

        (d)   Whenever the Partnership shall have one or more paying agents with respect to any series of Debt Securities, it will, prior to each due date of the principal of, and premium, if any, or interest on, any Debt Securities of such series, deposit with any such paying agent a sum sufficient to pay the principal, premium or interest so becoming due, such sum to be held in trust for the benefit of the Persons entitled thereto, and (unless any such paying agent is the Trustee) the Partnership will promptly notify the Trustee of its action or failure so to act.

        (e)   Anything in this Section 4.04 to the contrary notwithstanding, the agreement to hold sums in trust as provided in this Section 4.04 is subject to the provisions of Section 11.05.

        Section 4.05 SEC Reports; Financial Statements.

        (a)   The Partnership shall, so long as any of the Debt Securities are Outstanding, file with the Trustee, within 30 days after it files the same with the SEC, copies of the annual reports and the information, documents and other reports (or copies of such portions of any of the foregoing as the SEC may by rules and regulations prescribe) that the Partnership is required to file with the SEC pursuant to Section 13 or 15(d) of the Exchange Act. If the Partnership is not subject to the requirements of such Section 13 or 15(d), the Partnership shall file with the Trustee, within 30 days after it would have been required to file the same with the SEC, financial statements, including any notes thereto (and with respect to annual reports, an auditors' report by a firm of established national reputation), and a "Management's Discussion and Analysis of Financial Condition and Results of Operations," both comparable to that which the Partnership would have been required to include in such annual reports, information, documents or other reports if the Partnership had been subject to the

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requirements of such Section 13 or 15 (d). The Partnership shall also comply with the provisions of TIA Section 314 (a).

        (b)   The Partnership shall provide the Trustee with a sufficient number of copies of all reports and other documents and information that the Trustee may be required to deliver to Holders under this Section.

        (c)   The Partnership shall, so long as any of the Notes are Outstanding, deliver to the Trustee, within 30 days of any Officer of the Partnership becoming aware of the occurrence of any Event of Default, an Officers' Certificate specifying such Event of Default and what action the Partnership is taking or proposes to take with respect thereto.

        Section 4.06 Compliance Certificate.

        (a)   The Partnership and any Subsidiary Guarantor shall, so long as any of the Debt Securities are Outstanding, deliver to the Trustee, within 120 days after the end of each fiscal year of the Partnership, an Officers' Certificate stating that a review of the activities of the Partnership and its Subsidiaries during the preceding fiscal year has been made under the supervision of the signing Officers of the Partnership with a view to determining whether each of the Partnership and any Subsidiary Guarantor has kept, observed, performed and fulfilled its obligations under this Indenture, and further stating, as to each such Officer signing such certificate, that to the best of his knowledge each of the Partnership and any Subsidiary Guarantor has kept, observed, performed and fulfilled each and every covenant contained in this Indenture and is not in default in the performance or observance of any of the terms, provisions and conditions hereof, without regard to any grace period or requirement of notice required by this Indenture (or, if a Default or Event of Default shall have occurred, describing all such Defaults or Events of Default of which such Officer may have knowledge and what action the Partnership or any Subsidiary Guarantor is taking or proposes to take with respect thereto) and that to the best of his knowledge no event has occurred and remains in existence by reason of which payments on account of the principal of, or premium, if any, or interest, if any, on the Debt Securities are prohibited or, if such event has occurred, a description of the event and what action the Partnership or any Subsidiary Guarantor is taking or proposes to take with respect thereto.

        (b)   The Partnership shall, so long as any of the Debt Securities are Outstanding, deliver to the Trustee within 30 days after the occurrence of any Default or Event of Default under this Indenture, an Officers' Certificate specifying such Default or Event of Default, the status thereof and what action the Partnership is taking or proposes to take with respect thereto.

        Section 4.07 Further Instruments and Acts. The Partnership will, upon request of the Trustee, execute and deliver such further instruments and do such further acts as may reasonably be necessary or proper to carry out more effectually the purposes of this Indenture.

        Section 4.08 Existence. Except as permitted by Article X hereof, the Partnership shall do or cause to be done all things necessary to preserve and keep in full force and effect its existence and all rights (charter and statutory) and franchises of the Partnership, provided that the Partnership shall not be required to preserve any such right or franchise, if the Board of Directors shall determine that the preservation thereof is no longer desirable in the conduct of the business of the Partnership.

        Section 4.09 Maintenance of Properties. The Partnership shall cause all properties owned by the Partnership or any of its Subsidiaries or used or held for use in the conduct of its business or the business of any such Subsidiary to be maintained and kept in good condition, repair and working order (reasonable wear and tear excepted) and supplied with all necessary equipment and will cause to be made all necessary repairs, renewals, replacements, betterments and improvements thereof, all as in the judgment of the Partnership may be necessary so that the business carried on in connection therewith may be properly and advantageously conducted at all times; provided that nothing in this Section shall prevent the Partnership from discontinuing the operation or maintenance of any of such properties if

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such discontinuance is, in the judgment of the Partnership, desirable in the conduct of its business or the business of any such Subsidiary and not disadvantageous in any material respect to the Holders.

        Section 4.10 Payment of Taxes and Other Claims. The Partnership shall pay or discharge or cause to be paid or discharged, before the same shall become delinquent, (i) all taxes, assessments and governmental charges levied or imposed upon the Partnership or any of its Subsidiaries or upon the income, profits or property of the Partnership or any of its Subsidiaries, and (ii) all lawful claims for labor, materials and supplies which, if unpaid, might by law become a Lien upon the property of the Partnership or any of its Subsidiaries; provided that the Partnership shall not be required to pay or discharge or cause to be paid or discharged any such tax, assessment, charge or claim whose amount, applicability or validity is being contested in good faith by appropriate proceedings.

        Section 4.11 Waiver of Certain Covenants. The Partnership and the Subsidiary Guarantors may, with respect to the Debt Securities of any series, omit in any particular instance to comply with any covenant set forth in this Article IV (except Sections 4.01 through 4.08) or made applicable to such Debt Securities pursuant to Section 2.03, if, before or after the time for such compliance, the Holders of at least a majority in principal amount of the Outstanding Debt Securities of each series affected, waive such compliance in such instance with such covenant, but no such waiver shall extend to or affect such covenant except to the extent so expressly waived, and, until such waiver shall become effective, the obligations of the Partnership and the Subsidiary Guarantors and the duties of the Trustee in respect of any such covenant shall remain in full force and effect.

ARTICLE V

HOLDERS' LISTS AND REPORTS BY THE TRUSTEE

        Section 5.01 Partnership to Furnish Trustee Information as to Names and Addresses of Holders; Preservation of Information. The Partnership covenants and agrees that it will furnish or cause to be furnished to the Trustee with respect to the Debt Securities of each series:

        (a)   not more than 10 days after each record date with respect to the payment of interest, if any, a list, in such form as the Trustee may reasonably require, of the names and addresses of the Holders as of such record date, and

        (b)   at such other times as the Trustee may request in writing, within 30 days after the receipt by the Partnership of any such request, a list of similar form and contents as of a date not more than 15 days prior to the time such list is furnished;

provided, however, that so long as the Trustee shall be the Registrar, such lists shall not be required to be furnished.

        The Trustee shall preserve, in as current a form as is reasonably practicable, all information as to the names and addresses of the Holders (i) contained in the most recent list furnished to it as provided in this Section 5.01 or (ii) received by it in the capacity of paying agent or Registrar (if so acting) hereunder.

        The Trustee may destroy any list furnished to it as provided in this Section 5.01 upon receipt of a new list so furnished.

        Section 5.02 Communications to Holders. Holders may communicate pursuant to Section 312(b) of the TIA with other Holders with respect to their rights under this Indenture or the Debt Securities. The Partnership, the Trustee, the Registrar and anyone else shall have the protection of Section 312(c) of the TIA.

        Section 5.03 Reports by Trustee. Within 60 days after each January 31, beginning with the first January 31 following the date of this Indenture, and in any event on or before April 1 in each year, the

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Trustee shall mail to Holders a brief report dated as of such January 31 that complies with TIA Section 313 (a); provided, however, that if no event described in TIA Section 313 (a) has occurred within the twelve months preceding the reporting date, no report need be transmitted. The Trustee also shall comply with TIA Section 313 (b).

        Reports pursuant to this Section 5.03 shall be transmitted by mail:

        (a)   to all Holders, as the names and addresses of such Holders appear in the Debt Security Register; and

        (b)   except in the cases of reports under Section 313(b)(2) of the TIA, to each Holder of a Debt Security of any series whose name and address appear in the information preserved at the time by the Trustee in accordance with Section 5.01.

        A copy of each report at the time of its mailing to Holders shall be filed with the Securities and Exchange Commission and each stock exchange (if any) on which the Debt Securities of any series are listed. The Partnership agrees to notify promptly the Trustee whenever the Debt Securities of any series become listed on any stock exchange and of any delisting thereof.

        Section 5.04 Record Dates for Action by Holders. If the Partnership shall solicit from the Holders of Debt Securities of any series any action (including the making of any demand or request, the giving of any direction, notice, consent or waiver or the taking of any other action), the Partnership may, at its option, by resolution of the Board of Directors, fix in advance a record date for the determination of Holders of Debt Securities entitled to take such action, but the Partnership shall have no obligation to do so. Any such record date shall be fixed at the Partnership's discretion. If such a record date is fixed, such action may be sought or given before or after the record date, but only the Holders of Debt Securities of record at the close of business on such record date shall be deemed to be Holders of Debt Securities for the purpose of determining whether Holders of the requisite proportion of Debt Securities of such series Outstanding have authorized or agreed or consented to such action, and for that purpose the Debt Securities of such series Outstanding shall be computed as of such record date.

ARTICLE VI

REMEDIES OF THE TRUSTEE AND HOLDERS IN EVENT OF DEFAULT

        Section 6.01 Events of Default. If any one or more of the following shall have occurred and be continuing with respect to Debt Securities of any series (each of the following, an "Event of Default"):

        (a)   default in the payment of any installment of interest upon any Debt Securities of that series as and when the same shall become due and payable, whether or not such payment shall be prohibited by Article XII, if applicable, and continuance of such default for a period of 30 days; or

        (b)   default in the payment of the principal of or premium, if any, on any Debt Securities of that series as and when the same shall become due and payable, whether at Stated Maturity, upon redemption, by declaration, upon required repurchase or otherwise, whether or not such payment shall be prohibited by Article XII, if applicable; or

        (c)   default in the payment of any sinking fund payment with respect to any Debt Securities of that series as and when the same shall become due and payable; or

        (d)   failure on the part of the Partnership, or if any series of Debt Securities Outstanding under this Indenture is entitled to the benefits of the Guarantee, any of the Subsidiary Guarantors, duly to observe or perform any other of the covenants or agreements on the part of the Partnership, or if applicable, any of the Subsidiary Guarantors, in the Debt Securities of that series, in any resolution of the Board of Directors authorizing the issuance of that series of Debt Securities, in this Indenture with respect to such series or in any supplemental Indenture with respect to such series (other than a

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covenant a default in the performance of which is elsewhere in this Section specifically dealt with), continuing for a period of 60 days after the date on which written notice specifying such failure and requiring the Partnership, or if applicable, the Subsidiary Guarantors, to remedy the same shall have been given to the Partnership, or if applicable, the Subsidiary Guarantors, by the Trustee or to the Partnership, or if applicable, the Subsidiary Guarantors, and the Trustee by the Holders of at least 25% in aggregate principal amount of the Debt Securities of that series at the time Outstanding; or

        (e)   the Partnership, or if any series of Debt Securities Outstanding under this Indenture is entitled to the benefits of the Guarantee, any of the Subsidiary Guarantors, pursuant to or within the meaning of any Bankruptcy Law,

          (i)  commences a voluntary case,

         (ii)  consents to the entry of an order for relief against it in an involuntary case,

        (iii)  consents to the appointment of a Custodian of it or for all or substantially all of its property; or

        (iv)  makes a general assignment for the benefit of its creditors;

        (f)    a court of competent jurisdiction enters an order or decree under any Bankruptcy Law that:

          (i)  is for relief against the Partnership, or if any series of Debt Securities Outstanding under this Indenture is entitled to the benefits of the Guarantee, any of the Subsidiary Guarantors, as debtor in an involuntary case,

         (ii)  appoints a Custodian of the Partnership, or if any series of Debt Securities Outstanding under this Indenture is entitled to the benefits of the Guarantee, any of the Subsidiary Guarantors, or a Custodian for all or substantially all of the property of the Partnership, or if applicable, any of the Subsidiary Guarantors, or

        (iii)  orders the liquidation of the Partnership, or if any series of Debt Securities Outstanding under this Indenture is entitled to the benefits of the Guarantee, any of the Subsidiary Guarantors,

and the order or decree remains unstayed and in effect for 60 days;

        (iv)  if any series of Debt Securities Outstanding under this Indenture is entitled to the benefits of the Guarantee, the Guarantee of any of the Subsidiary Guarantors ceases to be in full force and effect with respect to Debt Securities of that series (except as otherwise provided in this Indenture) or is declared null and void in a judicial proceeding or any of the Subsidiary Guarantors denies or disaffirms its obligations under this Indenture or such Guarantee; or

         (v)  any other Event of Default provided with respect to Debt Securities of that series;

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then and in each and every case that an Event of Default described in clause (a), (b), (c), (d), (g), or (h) with respect to Debt Securities of that series at the time Outstanding occurs with respect to the Partnership and is continuing, unless the principal of, premium, if any, and accrued and unpaid interest on all the Debt Securities of that series shall have already become due and payable, either the Trustee or the Holders of not less than 25% in aggregate principal amount of the Debt Securities of that series then Outstanding hereunder, by notice in writing to the Partnership (and to the Trustee if given by Holders), may declare the principal of (or, if the Debt Securities of that series are Original Issue Discount Debt Securities, such portion of the principal amount as may be specified in the terms of that series), premium, if any, and interest on all the Debt Securities of that series to be due and payable immediately, and upon any such declaration the same shall become and shall be immediately due and payable, anything in this Indenture or in the Debt Securities of that series contained to the contrary notwithstanding. If an Event of Default described in clause (e) or (f) occurs with respect to the Partnership, then and in each and every such case, unless the principal of and accrued and unpaid interest on all the Debt Securities shall have become due and payable, the principal of (or, if the Debt Securities of that series are Original Issue Discount Debt Securities, such portion of the principal amount as may be specified in the terms thereof), premium, if any, and interest on all the Debt Securities then Outstanding hereunder shall ipso facto become and be immediately due and payable without any declaration or other act on the part of the Trustee or any Holders, anything in this Indenture or in the Debt Securities contained to the contrary notwithstanding.

        The Holders of a majority in aggregate principal amount of the Debt Securities of a particular series by written notice to the Trustee may rescind an acceleration and its consequences if the rescission would not conflict with any judgment or decree of a court of competent jurisdiction already rendered and if all existing Events of Default with respect to that series have been cured or waived except nonpayment of principal, premium, if any, or interest that has become due solely because of acceleration. Upon any such rescission, the parties hereto shall be restored respectively to their several positions and rights hereunder, and all rights, remedies and powers of the parties hereto shall continue as though no such proceeding had been taken.

        Section 6.02 Collection of Debt by Trustee, etc. If an Event of Default occurs and is continuing, the Trustee, in its own name and as trustee of an express trust, shall be entitled and empowered to institute any action or proceedings at law or in equity for the collection of the sums so due and unpaid or enforce the performance of any provision of the Debt Securities of the affected series or this Indenture, and may prosecute any such action or proceedings to judgment or final decree, and may enforce any such judgment or final decree against any of the Subsidiary Guarantors or the Partnership or any other obligor upon the Debt Securities of such series (and collect in the manner provided by law out of the property of any of the Subsidiary Guarantors or the Partnership or any other obligor upon the Debt Securities of such series wherever situated the moneys adjudged or decreed to be payable).

        In case there shall be pending proceedings for the bankruptcy or for the reorganization of any of the Subsidiary Guarantors or the Partnership or any other obligor upon the Debt Securities of any series under any Bankruptcy Law, or in case a Custodian shall have been appointed for its property, or in case of any other similar judicial proceedings relative to any of the Subsidiary Guarantors or the Partnership or any other obligor upon the Debt Securities of any series, its creditors or its property, the Trustee, irrespective of whether the principal of Debt Securities of any series shall then be due and payable as therein expressed or by declaration or otherwise and irrespective of whether the Trustee shall have made any demand pursuant to the provisions of this Section 6.02, shall be entitled and empowered, by intervention in such proceedings or otherwise, to file and prove a claim or claims for the whole amount of principal, premium, if any, and interest (or, if the Debt Securities of such series are Original Issue Discount Debt Securities, such portion of the principal amount as may be specified in the terms of such series) owing and unpaid in respect of the Debt Securities of such series, and to file such other papers or documents as may be necessary or advisable in order to have the claims of the

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Trustee (including any claim for reasonable compensation to the Trustee, its agents, attorneys and counsel, and for reimbursement of all expenses and liabilities incurred, and all advances made, by the Trustee except as a result of its negligence or bad faith) and of the Holders thereof allowed in any such judicial proceedings relative to any of the Subsidiary Guarantors or the Partnership, or any other obligor upon the Debt Securities of such series, its creditors or its property, and to collect and receive any moneys or other property payable or deliverable on any such claims, and to distribute all amounts received with respect to the claims of such Holders and of the Trustee on their behalf, and any receiver, assignee or trustee in bankruptcy or reorganization is hereby authorized by each of such Holders to make payments to the Trustee, and, in the event that the Trustee shall consent to the making of payments directly to such Holders, to pay to the Trustee such amount as shall be sufficient to cover reasonable compensation to the Trustee, its agents, attorneys and counsel, and all other reasonable expenses and liabilities incurred, and all advances made, by the Trustee except as a result of its negligence or bad faith.

        All rights of action and of asserting claims under this Indenture, or under any of the Debt Securities of any series, may be enforced by the Trustee without the possession of any such Debt Securities, or the production thereof in any trial or other proceedings relative thereto, and any such action or proceedings instituted by the Trustee shall be brought in its own name as trustee of an express trust, and any recovery of judgment (except for any amounts payable to the Trustee pursuant to Section 7.06) shall be for the ratable benefit of the Holders of all the Debt Securities in respect of which such action was taken.

        In case of an Event of Default hereunder the Trustee may in its discretion proceed to protect and enforce the rights vested in it by this Indenture by such appropriate judicial proceedings as the Trustee shall deem most effectual to protect and enforce any of such rights, either at law or in equity or in bankruptcy or otherwise, whether for the specific enforcement of any covenant or agreement contained in this Indenture or in aid of the exercise of any power granted in this Indenture, or to enforce any other legal or equitable right vested in the Trustee by this Indenture or by law.

        Section 6.03 Application of Moneys Collected by Trustee. Any moneys or other property collected by the Trustee pursuant to Section 6.02 with respect to Debt Securities of any series shall be applied, after giving effect to the provisions of Article XII, if applicable, in the order following, at the date or dates fixed by the Trustee for the distribution of such moneys or other property, upon presentation of the several Debt Securities of such series in respect of which moneys or other property have been collected, and the notation thereon of the payment, if only partially paid, and upon surrender thereof if fully paid:

        FIRST: To the payment of all money due the Trustee pursuant to Section 7.06;

        SECOND: In case the principal of the Outstanding Debt Securities in respect of which such moneys have been collected shall not have become due, to the payment of interest on the Debt Securities of such series in the order of the maturity of the installments of such interest, with interest (to the extent that such interest has been collected by the Trustee) upon the overdue installments of interest at the rate or Yield to Maturity (in the case of Original Issue Discount Debt Securities) borne by the Debt Securities of such series, such payments to be made ratably to the Persons entitled thereto, without discrimination or preference;

        THIRD: In case the principal of the Outstanding Debt Securities in respect of which such moneys have been collected shall have become due, by declaration or otherwise, to the payment of the whole amount then owing and unpaid upon the Debt Securities of such series for principal and premium, if any, and interest, with interest on the overdue principal and premium, if any, and (to the extent that such interest has been collected by the Trustee) upon overdue installments of interest at the rate or Yield to Maturity (in the case of Original Issue Discount Debt Securities) borne by the Debt Securities of such series; and, in case such moneys shall be insufficient to pay in full the whole amount so due

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and unpaid upon the Debt Securities of such series, then to the payment of such principal and premium, if any, and interest, without preference or priority of principal and premium, if any, over interest, or of interest over principal and premium, if any, or of any installment of interest over any other installment of interest, or of any Debt Security of such series over any Debt Security of such series, ratably to the aggregate of such principal and premium, if any, and interest; and

        FOURTH: The remainder, if any, shall be paid to the Subsidiary Guarantors or the Partnership, as applicable, its successors or assigns, or to whomsoever may be lawfully entitled to receive the same, or as a court of competent jurisdiction may direct.

        The Trustee may fix a record date and payment date for any payment to Holders pursuant to this Section 6.03. At least 15 days before such record date, the Partnership shall mail to each Holder and the Trustee a notice that states the record date, the payment date and amount to be paid.

        Section 6.04 Limitation on Suits by Holders. No Holder of any Debt Security of any series shall have any right by virtue or by availing of any provision of this Indenture to institute any action or proceeding at law or in equity or in bankruptcy or otherwise, upon or under or with respect to this Indenture, or for the appointment of a receiver or trustee, or for any other remedy hereunder, unless such Holder previously shall have given to the Trustee written notice of an Event of Default with respect to Debt Securities of that same series and of the continuance thereof and unless the Holders of not less than 25% in aggregate principal amount of the Outstanding Debt Securities of that series shall have made written request upon the Trustee to institute such action or proceedings in respect of such Event of Default in its own name as Trustee hereunder and shall have offered to the Trustee such reasonable indemnity or security as it may require against the costs, expenses and liabilities to be incurred therein or thereby, and the Trustee, for 60 days after its receipt of such notice, request and offer of indemnity or security shall have failed to institute any such action or proceedings and no direction inconsistent with such written request shall have been given to the Trustee pursuant to Section 6.06; it being understood and intended, and being expressly covenanted by the Holder of every Debt Security with every other Holder and the Trustee, that no one or more Holders shall have any right in any manner whatever by virtue or by availing of any provision of this Indenture to affect, disturb or prejudice the rights of any Holders, or to obtain or seek to obtain priority over or preference to any other such Holder, or to enforce any right under this Indenture, except in the manner herein provided and for the equal, ratable and common benefit of all such Holders. For the protection and enforcement of the provisions of this Section 6.04, each and every Holder and the Trustee shall be entitled to such relief as can be given either at law or in equity.

        Notwithstanding any other provision in this Indenture, however, the right of any Holder of any Debt Security to receive payment of the principal of, and premium, if any, and (subject to Section 2.12) interest on, such Debt Security, on or after the respective due dates expressed in such Debt Security, and to institute suit for the enforcement of any such payment on or after such respective dates, shall not be impaired or affected without the consent of such Holder.

        Section 6.05 Remedies Cumulative; Delay or Omission in Exercise of Rights Not a Waiver of Default. All powers and remedies given by this Article VI to the Trustee or to the Holders shall, to the extent permitted by law, be deemed cumulative and not exclusive of any thereof or of any other powers and remedies available to the Trustee or the Holders, by judicial proceedings or otherwise, to enforce the performance or observance of the covenants and agreements contained in this Indenture, and no delay or omission of the Trustee or of any Holder to exercise any right or power accruing upon any Default occurring and continuing as aforesaid, shall impair any such right or power, or shall be construed to be a waiver of any such Default or an acquiescence therein; and, subject to the provisions of Section 6.04, every power and remedy given by this Article VI or by law to the Trustee or to the Holders may be exercised from time to time, and as often as shall be deemed expedient, by the Trustee or by the Holders.

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        Section 6.06 Rights of Holders of Majority in Principal Amount of Debt Securities to Direct Trustee and to Waive Default. The Holders of not less than a majority in aggregate principal amount of the Debt Securities of any series at the time Outstanding shall have the right to direct the time, method and place of conducting any proceeding for any remedy available to the Trustee, or of exercising any right, trust or power conferred on the Trustee, with respect to the Debt Securities of such series; provided, however, that such direction shall not be otherwise than in accordance with law and the provisions of this Indenture, and that subject to the provisions of Section 7.01, the Trustee shall have the right to decline to follow any such direction if the Trustee being advised by counsel shall determine that the action so directed may not lawfully be taken or is inconsistent with any provision of this Indenture, or if the Trustee shall by a responsible officer or officers determine that the action so directed would involve it in personal liability or would be unduly prejudicial to Holders of Debt Securities of such series not taking part in such direction; and provided, further, however, that nothing in this Indenture contained shall impair the right of the Trustee to take any action deemed proper by the Trustee and which is not inconsistent with such direction by such Holders. The Holders of not less than a majority in aggregate principal amount of the Debt Securities of any series at the time Outstanding may on behalf of the Holders of all the Debt Securities of that series waive any past Default or Event of Default and its consequences for that series, except a Default or Event of Default in the payment of the principal of, and premium, if any, or interest on, any of the Debt Securities and a Default or Event of Default in respect of a provision that under Section 9.02 cannot be amended without the consent of each Holder affected thereby. In case of any such waiver, such Default shall cease to exist, any Event of Default arising therefrom shall be deemed to have been cured for every purpose of this Indenture, and the Subsidiary Guarantors, the Partnership, the Trustee and the Holders of the Debt Securities of that series shall be restored to their former positions and rights hereunder, respectively; but no such waiver shall extend to any subsequent or other Default or Event of Default or impair any right consequent thereon.

        Section 6.07 Trustee to Give Notice of Events of Defaults Known to It, but May Withhold Such Notice in Certain Circumstances. The Trustee shall, within 90 days after the occurrence of an Event of Default, or if later, within 30 days after the Trustee obtains actual knowledge of the Event of Default, with respect to a series of Debt Securities give to the Holders thereof, in the manner provided in Section 13.03, notice of all Events of Default with respect to such series known to the Trustee, unless such Events of Default shall have been cured or waived before the giving of such notice; provided, that, except in the case of an Event of Default in the payment of the principal of, or premium, if any, or interest on, any of the Debt Securities of such series or in the making of any sinking fund payment with respect to the Debt Securities of such series, the Trustee shall be protected in withholding such notice if and so long as the board of directors, the executive committee or a committee of directors or responsible officers of the Trustee in good faith determines that the withholding of such notice is in the interests of the Holders thereof.

        Section 6.08 Requirement of an Undertaking to Pay Costs in Certain Suits under the Indenture or Against the Trustee. All parties to this Indenture agree, and each Holder of any Debt Security by his acceptance thereof shall be deemed to have agreed, that any court may in its discretion require, in any suit for the enforcement of any right or remedy under this Indenture, or in any suit against the Trustee for any action taken or omitted by it as Trustee, the filing by any party litigant in such suit of an undertaking to pay the costs of such suit in the manner and to the extent provided in the TIA, and that such court may in its discretion assess reasonable costs, including reasonable attorneys' fees and expenses, against any party litigant in such suit, having due regard to the merits and good faith of the claims or defenses made by such party litigant; but the provisions of this Section 6.08 shall not apply to any suit instituted by the Trustee, to any suit instituted by any Holder, or group of Holders, holding in the aggregate more than 25 percent in principal amount of the Outstanding Debt Securities of that series or to any suit instituted by any Holder for the enforcement of the payment of the principal of, or

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premium, if any, or interest on, any Debt Security on or after the due date for such payment expressed in such Debt Security.

ARTICLE VII

CONCERNING THE TRUSTEE

        Section 7.01 Certain Duties and Responsibilities. The Trustee, prior to the occurrence of an Event of Default and after the curing or waiving of all Events of Default which may have occurred, undertakes to perform such duties and only such duties as are specifically set forth in this Indenture. In case an Event of Default has occurred (which has not been cured or waived), the Trustee shall exercise such of the rights and powers vested in it by this Indenture, and use the same degree of care and skill in their exercise, as a prudent man would exercise or use under the circumstances in the conduct of his own affairs.

        No provision of this Indenture shall be construed to relieve the Trustee from liability for its own negligent action, its own negligent failure to act, its own bad faith or its own willful misconduct, except that:

        (a)   this paragraph shall not be construed to limit the effect of the first paragraph of this Section 7.01;

        (b)   prior to the occurrence of an Event of Default with respect to the Debt Securities of a series and after the curing or waiving of all Events of Default with respect to such series which may have occurred:

          (i)  the duties and obligations of the Trustee with respect to Debt Securities of any series shall be determined solely by the express provisions of this Indenture, and the Trustee shall not be liable except for the performance of such duties and obligations with respect to such series as are specifically set forth in this Indenture, and no implied covenants or obligations with respect to such series shall be read into this Indenture against the Trustee;

         (ii)  in the absence of bad faith on the part of the Trustee, the Trustee may conclusively rely, as to the truth of the statements and the correctness of the opinions expressed therein, upon any certificates or opinions furnished to the Trustee and conforming to the requirements of this Indenture; but in the case of any such certificates or opinions which by any provision hereof are specifically required to be furnished to the Trustee, the Trustee shall be under a duty to examine the same to determine whether or not they conform to the requirements of this Indenture; but the Trustee shall examine the evidence furnished to it pursuant to Sections 4.05 and 4.06 to determine whether or not such evidence conforms to the requirement of this Indenture;

        (iii)  the Trustee shall not be liable for an error of judgment made in good faith by a responsible officer, unless it shall be proved that the Trustee was negligent in ascertaining the pertinent facts; and

        (iv)  the Trustee shall not be liable with respect to any action taken or omitted to be taken by it with respect to Debt Securities of any series in good faith in accordance with the direction of the Holders of not less than a majority in aggregate principal amount of the Outstanding Debt Securities of that series relating to the time, method and place of conducting any proceeding for any remedy available to the Trustee, or exercising any trust or power conferred upon the Trustee, under this Indenture with respect to Debt Securities of such series.

        None of the provisions of this Indenture shall require the Trustee to expend or risk its own funds or otherwise incur any personal financial liability in the performance of any of its duties hereunder, or in the exercise of any of its rights or powers, if there shall be reasonable grounds for believing that

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repayment of such funds or adequate indemnity against such risk or liability is not reasonably assured to it.

        Whether or not therein expressly so provided, every provision of this Indenture relating to the conduct or affecting the liability of or affording protection to the Trustee shall be subject to the provisions of this Section.

        Section 7.02 Certain Rights of Trustee. Except as otherwise provided in Section 7.01:

        (a)   the Trustee may rely and shall be protected in acting or refraining from acting upon any resolution, certificate, statement, instrument, opinion, report, notice, request, direction, consent, order, bond, debenture, note or other paper or document (whether in its original or facsimile form) believed by it to be genuine and to have been signed or presented by the proper party or parties;

        (b)   any request, direction, order or demand of the Partnership mentioned herein shall be sufficiently evidenced by a Partnership Order (unless other evidence in respect thereof be herein specifically prescribed); and any resolution of the Board of Directors may be evidenced to the Trustee by a copy thereof certified by the Secretary or an Assistant Secretary of the Partnership;

        (c)   the Trustee may consult with counsel, and the advice of such counsel or any Opinion of Counsel shall be full and complete authorization and protection in respect of any action taken or suffered or omitted by it hereunder in good faith and in accordance with such advice or Opinion of Counsel;

        (d)   the Trustee shall be under no obligation to exercise any of the rights or powers vested in it by this Indenture at the request, order or direction of any of the Holders of Debt Securities of any series pursuant to the provisions of this Indenture, unless such Holders shall have offered to the Trustee reasonable security or indemnity against the costs, expenses and liabilities which may be incurred therein or thereby;

        (e)   the Trustee shall not be liable for any action taken or omitted by it in good faith and reasonably believed by it to be authorized or within the discretion or rights or powers conferred upon it by this Indenture;

        (f)    prior to the occurrence of an Event of Default and after the curing of all Events of Default which may have occurred, the Trustee shall not be bound to make any investigation into the facts or matters stated in any resolution, certificate, statement, instrument, opinion, report, notice, request, direction, consent, order, approval or other paper or document, unless requested in writing to do so by the Holders of a majority in aggregate principal amount of the then Outstanding Debt Securities of a series affected by such matter; provided, however, that if the payment within a reasonable time to the Trustee of the costs, expenses or liabilities likely to be incurred by it in the making of such investigation is not, in the opinion of the Trustee, reasonably assured to the Trustee by the security afforded to it by the terms of this Indenture, the Trustee may require reasonable indemnity against such costs, expenses or liabilities as a condition to so proceeding, and the reasonable expense of every such investigation shall be paid by the Partnership or, if paid by the Trustee, shall be repaid by the Partnership upon demand;

        (g)   the Trustee may execute any of the trusts or powers hereunder or perform any duties hereunder either directly or by or through agents or attorneys and the Trustee shall not be responsible for any misconduct or negligence on the part of any agent or attorney appointed by it with due care hereunder; and

        (h)   if any property other than cash shall at any time be subject to a Lien in favor of the Holders, the Trustee, if and to the extent authorized by a receivership or bankruptcy court of competent jurisdiction or by the supplemental instrument subjecting such property to such Lien, shall be entitled

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to make advances for the purpose of preserving such property or of discharging tax Liens or other prior Liens or encumbrances thereon.

        Section 7.03 Trustee Not Liable for Recitals in Indenture or in Debt Securities. The recitals contained herein, in the Debt Securities (except the Trustee's certificate of authentication) shall be taken as the statements of the Partnership, and the Trustee assumes no responsibility for the correctness of the same. The Trustee makes no representations as to the validity or sufficiency of this Indenture or of the Debt Securities of any series, except that the Trustee represents that it is duly authorized to execute and deliver this Indenture, authenticate the Debt Securities and perform its obligations hereunder, and that the statements made by it or to be made by it in a Statement of Eligibility and Qualification on Form T-1 supplied to the Partnership are true and accurate. The Trustee shall not be accountable for the use or application by the Partnership of any of the Debt Securities or of the proceeds thereof.

        Section 7.04 Trustee, Paying Agent or Registrar May Own Debt Securities. The Trustee or any paying agent or Registrar, in its individual or any other capacity, may become the owner or pledgee of Debt Securities and subject to the provisions of the TIA relating to conflicts of interest and preferential claims may otherwise deal with the Partnership with the same rights it would have if it were not Trustee, paying agent or Registrar.

        Section 7.05 Moneys Received by Trustee to Be Held in Trust. Subject to the provisions of Section 11.05, all moneys received by the Trustee shall, until used or applied as herein provided, be held in trust for the purposes for which they were received, but need not be segregated from other funds except to the extent required by law. The Trustee shall be under no liability for interest on any moneys received by it hereunder. So long as no Event of Default shall have occurred and be continuing, all interest allowed on any such moneys shall be paid from time to time to the Partnership upon a Partnership Order.

        Section 7.06 Compensation and Reimbursement. The Partnership covenants and agrees to pay in Dollars to the Trustee from time to time, and the Trustee shall be entitled to, reasonable compensation for all services rendered by it hereunder (which shall not be limited by any provision of law in regard to the compensation of a trustee of an express trust), and, except as otherwise expressly provided herein, the Partnership will pay or reimburse in Dollars the Trustee upon its request for all reasonable expenses, disbursements and advances incurred or made by the Trustee in accordance with any of the provisions of this Indenture (including the reasonable compensation and the expenses and disbursements of its agents, attorneys and counsel and of all Persons not regularly in its employ), including without limitation, Section 6.02, except any such expense, disbursement or advances as may arise from its negligence, willful misconduct or bad faith. The Partnership also covenants to indemnify in Dollars the Trustee for, and to hold it harmless against, any loss, liability or expense incurred without negligence, willful misconduct or bad faith on the part of the Trustee, arising out of or in connection with the acceptance or administration of this trust or trusts hereunder, including the reasonable costs and expenses of defending itself against any claim of liability in connection with the exercise or performance of any of its powers or duties hereunder. The obligations of the Partnership under this Section 7.06 to compensate and indemnify the Trustee and to pay or reimburse the Trustee for expenses, disbursements and advances shall constitute additional Debt hereunder and shall survive the satisfaction and discharge of this Indenture. The Partnership and the Holders agree that such additional Debt shall be secured by a Lien prior to that of the Debt Securities upon all property and funds held or collected by the Trustee, as such, except funds held in trust for the payment of principal of, and premium, if any, or interest on, particular Debt Securities.

        When the Trustee incurs expenses or renders services after an Event of Default specified in Section 6.01(e) or (f) occurs, the expenses and the compensation for the services are intended to constitute expenses of administration under any Bankruptcy Law.

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        Section 7.07 Right of Trustee to Rely on an Officers' Certificate Where No Other Evidence Specifically Prescribed. Except as otherwise provided in Section 7.01, whenever in the administration of the provisions of this Indenture the Trustee shall deem it necessary or desirable that a matter be proved or established prior to taking or suffering or omitting any action hereunder, such matter (unless other evidence in respect thereof be herein specifically prescribed) may, in the absence of negligence or bad faith on the part of the Trustee, be deemed to be conclusively proved and established by an Officers' Certificate delivered to the Trustee and such certificate, in the absence of negligence or bad faith on the part of the Trustee, shall be full warrant to the Trustee for any action taken, suffered or omitted by it under the provisions of this Indenture upon the faith thereof.

        Section 7.08 Separate Trustee; Replacement of Trustee. The Partnership may, but need not, appoint a separate Trustee for any one or more series of Debt Securities. The Trustee may resign with respect to one or more or all series of Debt Securities at any time by giving notice to the Partnership.

        The Holders of a majority in principal amount of the Debt Securities of a particular series may remove the Trustee for such series and only such series by so notifying the Trustee and may appoint a successor Trustee. The Partnership shall remove the Trustee if:

        (a)   the Trustee fails to comply with Section 7.10;

        (b)   the Trustee is adjudged bankrupt or insolvent;

        (c)   a Custodian takes charge of the Trustee or its property; or

        (d)   the Trustee otherwise becomes incapable of acting.

        If the Trustee resigns, is removed by the Partnership or by the Holders of a majority in principal amount of the Debt Securities of a particular series and such Holders do not reasonably promptly appoint a successor Trustee, or if a vacancy exists in the office of Trustee for any reason (the Trustee in such event being referred to herein as the retiring Trustee), the Partnership shall promptly appoint a successor Trustee. No resignation or removal of the Trustee and no appointment of a successor Trustee shall become effective until the acceptance of appointment by the successor Trustee in accordance with the applicable requirements of this Section 7.08.

        A successor Trustee shall deliver a written acceptance of its appointment to the retiring Trustee and to the Partnership. Thereupon the resignation or removal of the retiring Trustee shall become effective, and the successor Trustee shall have all the rights, powers and duties of the Trustee under this Indenture. The successor Trustee shall mail a notice of its succession to Holders of Debt Securities of each applicable series. The retiring Trustee shall promptly transfer all property held by it as Trustee to the successor Trustee, subject to the Lien provided for in Section 7.06.

        If a successor Trustee does not take office within 60 days after the retiring Trustee gives notice of resignation or is removed, the retiring Trustee or the Holders of 25% in principal amount of the Debt Securities of any applicable series may petition any court of competent jurisdiction for the appointment of a successor Trustee for the Debt Securities of such series.

        If the Trustee fails to comply with Section 7.10, any Holder of Debt Securities of any applicable series may petition any court of competent jurisdiction for the removal of the Trustee and the appointment of a successor Trustee for the Debt Securities of such series.

        Notwithstanding the replacement of the Trustee pursuant to this Section 7.08, the Partnership's obligations under Section 7.06 shall continue for the benefit of the retiring Trustee.

        In the case of the appointment hereunder of a separate or successor Trustee with respect to the Debt Securities of one or more series, the Partnership, any retiring Trustee and each successor or separate Trustee with respect to the Debt Securities of any applicable series shall execute and deliver an Indenture supplemental hereto (i) which shall contain such provisions as shall be deemed necessary

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or desirable to confirm that all the rights, powers, trusts and duties of any retiring Trustee with respect to the Debt Securities of any series as to which any such retiring Trustee is not retiring shall continue to be vested in such retiring Trustee and (ii) that shall add to or change any of the provisions of this Indenture as shall be necessary to provide for or facilitate the administration of the trusts hereunder by more than one trustee, it being understood that nothing herein or in such supplemental Indenture shall constitute such Trustees co-trustees of the same trust and that each such separate, retiring or successor Trustee shall be Trustee of a trust or trusts hereunder separate and apart from any trust or trusts hereunder administered by any other such Trustee.

        Section 7.09 Successor Trustee by Merger. If the Trustee consolidates with, merges or converts into, or transfers all or substantially all its corporate trust business or assets to, another corporation or banking association, the resulting, surviving or transferee corporation or banking association without any further act shall be the successor Trustee.

        In case at the time such successor or successors to the Trustee by merger, conversion, consolidation or transfer shall succeed to the trusts created by this Indenture any of the Debt Securities shall have been authenticated but not delivered, any such successor to the Trustee may adopt the certificate of authentication of any predecessor Trustee, and deliver such Debt Securities so authenticated; and in case at that time any of the Debt Securities shall not have been authenticated, any successor to the Trustee may authenticate such Debt Securities either in the name of any predecessor hereunder or in the name of the successor to the Trustee; and in all such cases such certificates shall have the full force which it is anywhere in the Debt Securities or in this Indenture provided that the certificate of the Trustee shall have.

        Section 7.10 Eligibility; Disqualification. The Trustee shall at all times satisfy the requirements of Section 310(a) of the TIA. The Trustee shall have a combined capital and surplus of at least $50,000,000 as set forth in its most recent published annual report of condition. No obligor upon the Debt Securities of a particular series or Person directly or indirectly controlling, controlled by or under common control with such obligor shall serve as Trustee for the Debt Securities of such series. The Trustee shall comply with Section 310(b) of the TIA; provided, however, that there shall be excluded from the operation of Section 310(b)(1) of the TIA this Indenture or any indenture or indentures under which other securities or certificates of interest or participation in other securities of the Partnership are outstanding if the requirements for such exclusion set forth in Section 310(b)(1) of the TIA are met.

        Section 7.11 Preferential Collection of Claims Against Partnership. The Trustee shall comply with Section 311(a) of the TIA, excluding any creditor relationship listed in Section 311(b) of the TIA. A Trustee who has resigned or been removed shall be subject to Section 311(a) of the TIA to the extent indicated therein.

        Section 7.12 Compliance with Tax Laws. The Trustee hereby agrees to comply with all U.S. Federal income tax information reporting and withholding requirements applicable to it with respect to payments of premium (if any) and interest on the Debt Securities, whether acting as Trustee, Registrar, paying agent or otherwise with respect to the Debt Securities.

ARTICLE VIII

CONCERNING THE HOLDERS

        Section 8.01 Evidence of Action by Holders. Whenever in this Indenture it is provided that the Holders of a specified percentage in aggregate principal amount of the Debt Securities of any or all series may take action (including the making of any demand or request, the giving of any direction, notice, consent or waiver or the taking of any other action) the fact that at the time of taking any such action the Holders of such specified percentage have joined therein may be evidenced (a) by any

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instrument or any number of instruments of similar tenor executed by Holders in Person or by agent or proxy appointed in writing, (b) by the record of the Holders voting in favor thereof at any meeting of Holders duly called and held in accordance with the provisions of Section 5.02, (c) by a combination of such instrument or instruments and any such record of such a meeting of Holders or (d) in the case of Debt Securities evidenced by a Global Security, by any electronic transmission or other message, whether or not in written format, that complies with the Depositary's applicable procedures.

        Section 8.02 Proof of Execution of Instruments and of Holding of Debt Securities. Subject to the provisions of Sections 7.01, 7.02 and 13.09, proof of the execution of any instrument by a Holder or his agent or proxy shall be sufficient if made in accordance with such reasonable rules and regulations as may be prescribed by the Trustee or in such manner as shall be satisfactory to the Trustee. The ownership of Debt Securities of any series shall be proved by the Debt Security Register or by a certificate of the Registrar for such series. The Trustee may require such additional proof of any matter referred to in this Section 8.02 as it shall deem necessary.

        Section 8.03 Who May Be Deemed Owner of Debt Securities. Prior to due presentment for registration of transfer of any Debt Security, the Partnership, the Subsidiary Guarantors, the Trustee, any paying agent and any Registrar may deem and treat the Person in whose name any Debt Security shall be registered upon the books of the Partnership as the absolute owner of such Debt Security (whether or not such Debt Security shall be overdue and notwithstanding any notation of ownership or other writing thereon) for the purpose of receiving payment of or on account of the principal of and premium, if any, and (subject to Section 2.12) interest on such Debt Security and for all other purposes, and none of the Partnership, the Subsidiary Guarantors or the Trustee nor any paying agent nor any Registrar shall be affected by any notice to the contrary; and all such payments so made to any such Holder for the time being, or upon his order, shall be valid and, to the extent of the sum or sums so paid, effectual to satisfy and discharge the liability for moneys payable upon any such Debt Security.

        None of the Partnership, the Subsidiary Guarantors, the Trustee, any paying agent or any Registrar will have any responsibility or liability for any aspect of the records relating to or payments made on account of beneficial ownership interests in a Global Security or for maintaining, supervising or reviewing any records relating to such beneficial ownership interests.

        Section 8.04 Instruments Executed by Holders Bind Future Holders. At any time prior to (but not after) the evidencing to the Trustee, as provided in Section 8.01, of the taking of any action by the Holders of the percentage in aggregate principal amount of the Debt Securities of any series specified in this Indenture in connection with such action and subject to the following paragraph, any Holder of a Debt Security which is shown by the evidence to be included in the Debt Securities the Holders of which have consented to such action may, by filing written notice with the Trustee at its corporate trust office and upon proof of holding as provided in Section 8.02, revoke such action so far as concerns such Debt Security. Except as aforesaid any such action taken by the Holder of any Debt Security shall be conclusive and binding upon such Holder and upon all future Holders and owners of such Debt Security and of any Debt Security issued upon transfer thereof or in exchange or substitution therefor, irrespective of whether or not any notation in regard thereto is made upon such Debt Security or such other Debt Securities. Any action taken by the Holders of the percentage in aggregate principal amount of the Debt Securities of any series specified in this Indenture in connection with such action shall be conclusively binding upon the Partnership, the Subsidiary Guarantors, the Trustee and the Holders of all the Debt Securities of such series.

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        The Partnership may, but shall not be obligated to, fix a record date for the purpose of determining the Holders of Debt Securities entitled to give their consent or take any other action required or permitted to be taken pursuant to this Indenture. If a record date is fixed, then notwithstanding the immediately preceding paragraph, those Persons who were Holders of Debt Securities at such record date (or their duly designated proxies), and only those Persons, shall be entitled to give such consent or to revoke any consent previously given or to take any such action, whether or not such Persons continue to be Holders of Debt Securities after such record date. No such consent shall be valid or effective for more than 120 days after such record date unless the consent of the Holders of the percentage in aggregate principal amount of the Debt Securities of such series specified in this Indenture shall have been received within such 120-day period.

ARTICLE IX

SUPPLEMENTAL INDENTURES

        Section 9.01 Purposes for Which Supplemental Indenture May Be Entered into Without Consent of Holders. The Partnership and any Subsidiary Guarantors, when authorized by resolutions of the Board of Directors, and the Trustee may from time to time and at any time, without the consent of Holders, enter into an Indenture or Indentures supplemental hereto (which shall conform to the provisions of the TIA as in force at the date of the execution thereof) for one or more of the following purposes:

        (a)   to evidence the succession pursuant to Article X of another Person to the Partnership, or successive successions, and the assumption by the Successor Partnership (as defined in Section 10.01) of the covenants, agreements and obligations of the Partnership in this Indenture and in the Debt Securities;

        (b)   to surrender any right or power herein conferred upon the Partnership or the Subsidiary Guarantors, to add to the covenants of the Partnership or the Subsidiary Guarantors such further covenants, restrictions, conditions or provisions for the protection of the Holders of all or any series of Debt Securities (and if such covenants are to be for the benefit of less than all series of Debt Securities, stating that such covenants are expressly being included solely for the benefit of such series) as the Board of Directors shall consider to be for the protection of the Holders of such Debt Securities, and to make the occurrence, or the occurrence and continuance, of a Default in any of such additional covenants, restrictions, conditions or provisions a Default or an Event of Default permitting the enforcement of all or any of the several remedies provided in this Indenture; provided, that in respect of any such additional covenant, restriction, condition or provision such supplemental Indenture may provide for a particular period of grace after Default (which period may be shorter or longer than that allowed in the case of other Defaults) or may provide for an immediate enforcement upon such Default or may limit the remedies available to the Trustee upon such Default or may limit the right of the Holders of a majority in aggregate principal amount of any or all series of Debt Securities to waive such Default;

        (c)   to cure any ambiguity or omission or to correct or supplement any provision contained herein, in any supplemental Indenture or in any Debt Securities of any series that may be defective or inconsistent with any other provision contained herein, in any supplemental Indenture or in the Debt Securities of such series; to convey, transfer, assign, mortgage or pledge any property to or with the Trustee, or to make such other provisions in regard to matters or questions arising under this Indenture as shall not adversely affect the interests of any Holders of Debt Securities of any series;

        (d)   to permit the qualification of this Indenture or any Indenture supplemental hereto under the TIA as then in effect, except that nothing herein contained shall permit or authorize the inclusion in any Indenture supplemental hereto of the provisions referred to in Section 316(a)(2) of the TIA;

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        (e)   to change or eliminate any restrictions on the payment of principal of, or premium, if any, on, Debt Securities; provided, that any such action shall not adversely affect the interests of the Holders of Debt Securities of any series in any material respect or permit or facilitate the issuance of Debt Securities of any series in uncertificated form;

        (f)    to reflect the release of any Subsidiary Guarantor in accordance with Article XIV;

        (g)   in the case of any Debt Securities subordinated pursuant to Article XII, to make any change in Article XII that would limit or terminate the benefits available to any holder of Senior Indebtedness (or Representatives therefor) under Article XII;

        (h)   to add Subsidiary Guarantors with respect to any or all of the Debt Securities or to secure any or all of the Debt Securities or the Guarantee;

        (i)    to make any change that does not adversely affect the rights hereunder of any Holder;

        (j)    to add to, change or eliminate any of the provisions of this Indenture in respect of one or more series of Debt Securities; provided, however, that any such addition, change or elimination not otherwise permitted under this Section 9.01 shall neither apply to any Debt Security of any series created prior to the execution of such supplemental Indenture and entitled to the benefit of such provision nor modify the rights of the Holder of any such Debt Security with respect to such provision or shall become effective only when there is no such Debt Security Outstanding;

        (k)   to evidence and provide for the acceptance of appointment hereunder by a successor or separate Trustee with respect to the Debt Securities of one or more series and to add to or change any of the provisions of this Indenture as shall be necessary to provide for or facilitate the administration of the trusts hereunder by more than one Trustee; and

        (l)    to establish the form or terms of Debt Securities of any series as permitted by Sections 2.01 and 2.03.

        The Trustee is hereby authorized to join with the Partnership and the Subsidiary Guarantors in the execution of any such supplemental Indenture, to make any further appropriate agreements and stipulations which may be therein contained and to accept the conveyance, transfer, assignment, mortgage or pledge of any property thereunder, but the Trustee shall not be obligated to enter into any such supplemental Indenture which affects the Trustee's own rights, duties or immunities under this Indenture or otherwise.

        Any supplemental Indenture authorized by the provisions of this Section 9.01 may be executed by the Partnership, the Subsidiary Guarantors and the Trustee without the consent of the Holders of any of the Debt Securities at the time Outstanding, notwithstanding any of the provisions of Section 9.02.

        In the case of Debt Securities subordinated pursuant to Article XII, an amendment under this Section 9.01 may not make any change that adversely affects the rights under Article XII of any holder of Senior Indebtedness then outstanding unless the holders of such Senior Indebtedness (or any group or Representative thereof authorized to give a consent) consent to such change.

        Section 9.02 Modification of Indenture with Consent of Holders of Debt Securities. Without notice to any Holder but with the consent (evidenced as provided in Section 8.01) of the Holders of not less than a majority in aggregate principal amount of the Outstanding Debt Securities of each series affected by such supplemental Indenture (including consents obtained in connection with a tender offer or exchange offer for any such series of Debt Securities), the Partnership and the Subsidiary Guarantors, when authorized by resolutions of the Board of Directors, and the Trustee may from time to time and at any time enter into an Indenture or Indentures supplemental hereto (which shall conform to the provisions of the TIA as in force at the date of execution thereof) for the purpose of adding any provisions to or changing in any manner or eliminating any of the provisions of this

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Indenture or of any supplemental Indenture or of modifying in any manner the rights of the Holders of the Debt Securities of such series; provided, that no such supplemental Indenture, without the consent of the Holders of each Debt Security so affected, shall: reduce the percentage in principal amount of Debt Securities of any series whose Holders must consent to an amendment; reduce the rate of or extend the time for payment of interest on any Debt Security; reduce the principal of or extend the Stated Maturity of any Debt Security; reduce any premium payable upon the redemption of any Debt Security or change the time at which any Debt Security may or shall be redeemed in accordance with Article III; make any Debt Security payable in currency other than the Dollar; impair the right of any Holder to receive payment of premium, if any, principal of and interest on such Holder's Debt Securities on or after the due dates therefor or to institute suit for the enforcement of any payment on or with respect to such Holder's Debt Securities; in the case of any Debt Security subordinated pursuant to Article XII, make any change in Article XII that adversely affects the rights of any Holder under Article XII; release any security that may have been granted in respect of the Debt Securities, other than in accordance with this Indenture; make any change in Section 6.06 or this Section 9.02; or, except as provided in Section 11.02(b) or Section 14.04, release the Subsidiary Guarantors other than as provided in this Indenture or modify the Guarantee in any manner adverse to the Holders.

        A supplemental Indenture which changes or eliminates any covenant or other provision of this Indenture which has been expressly included solely for the benefit of one or more particular series of Debt Securities or which modifies the rights of the Holders of Debt Securities of such series with respect to such covenant or other provision, shall be deemed not to affect the rights under this Indenture of the Holders of Debt Securities of any other series.

        Upon the request of the Partnership and the Subsidiary Guarantors, accompanied by a copy of resolutions of the Board of Directors authorizing the execution of any such supplemental Indenture, and upon the filing with the Trustee of evidence of the consent of Holders as aforesaid, the Trustee shall join with the Partnership in the execution of such supplemental Indenture unless such supplemental Indenture affects the Trustee's own rights, duties or immunities under this Indenture or otherwise, in which case the Trustee may in its discretion but shall not be obligated to enter into such supplemental Indenture.

        It shall not be necessary for the consent of the Holders under this Section 9.02 to approve the particular form of any proposed supplemental Indenture, but it shall be sufficient if such consent shall approve the substance thereof.

        In the case of any Debt Securities subordinated pursuant to Article XII, an amendment under this Section 9.02 may not make any change that adversely affects the rights under Article XII of any holder of Senior Indebtedness then outstanding unless the holders of such Senior Indebtedness (or any group or Representative thereof authorized to give a consent) consent to such change.

        After an amendment under this Section 9.02 requiring the consent of the Holders of any series of Debt Securities becomes effective, the Partnership shall mail to Holders of that series of Debt Securities of each series affected thereby a notice briefly describing such amendment. The failure to give such notice to any such Holders, or any defect therein, shall not impair or affect the validity of an amendment under this Section 9.02 with respect to other Holders.

        Section 9.03 Effect of Supplemental Indentures. Upon the execution of any supplemental Indenture pursuant to the provisions of this Article IX, this Indenture shall be and be deemed to be modified and amended in accordance therewith and the respective rights, limitations of rights, obligations, duties and immunities under this Indenture of the Trustee, the Partnership, the Subsidiary Guarantors and the Holders shall thereafter be determined, exercised and enforced hereunder subject in all respects to such modifications and amendments, and all the terms and conditions of any such supplemental Indenture shall be and be deemed to be part of the terms and conditions of this Indenture for any and all purposes.

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        The Trustee, subject to the provisions of Sections 7.01 and 7.02, may receive an Officers' Certificate and an Opinion of Counsel as conclusive evidence that any such supplemental Indenture complies with the provisions of this Article IX.

        Section 9.04 Debt Securities May Bear Notation of Changes by Supplemental Indentures. Debt Securities of any series authenticated and delivered after the execution of any supplemental Indenture pursuant to the provisions of this Article IX may, and shall if required by the Trustee, bear a notation in form approved by the Trustee as to any matter provided for in such supplemental Indenture. New Debt Securities of any series so modified as to conform, in the opinion of the Trustee and the Board of Directors, to any modification of this Indenture contained in any such supplemental Indenture may be prepared and executed by the Partnership, authenticated by the Trustee and delivered in exchange for the Debt Securities of such series then Outstanding. Failure to make the appropriate notation or to issue a new Debt Security of such series shall not affect the validity of such amendment.

ARTICLE X

CONSOLIDATION, MERGER, SALE OR CONVEYANCE

        Section 10.01 Consolidations and Mergers of the Partnership. The Partnership shall not consolidate or amalgamate with or merge with or into any Person, or sell, convey, transfer, lease or otherwise dispose of all or substantially all its assets to any Person, whether in a single transaction or a series of related transactions, except (1) in accordance with the provisions of its Partnership agreement, and (2) unless: (a) either (i) the Partnership shall be the surviving Person in the case of a merger or (ii) the resulting, surviving or transferee Person if other than the Partnership (the "Successor Partnership"), shall be a Partnership, limited liability company or corporation organized and existing under the laws of the United States, any State thereof or the District of Columbia and the Successor Partnership shall expressly assume, by an Indenture supplemental hereto, executed and delivered to the Trustee, in form satisfactory to the Trustee, all the obligations of the Partnership under this Indenture and the Debt Securities according to their tenor; (b) immediately after giving effect to such transaction or series of transactions (and treating any Debt which becomes an obligation of the Successor Partnership or any Subsidiary of the Partnership as a result of such transaction as having been incurred by the Successor Partnership or such Subsidiary at the time of such transaction or series of transactions), no Default or Event of Default would occur or be continuing; (c) if the Partnership is not the continuing Person, then each Subsidiary Guarantor, unless it has become the Successor Partnership, shall confirm that its Guarantee shall continue to apply to the obligations under the Debt Securities and this Indenture; and (d) the Partnership shall have delivered to the Trustee an Officers' Certificate and an Opinion of Counsel, each stating that such consolidation, amalgamation, merger or disposition and such supplemental Indenture (if any) comply with this Indenture.

        Section 10.02 Rights and Duties of Successor Partnership. In case of any consolidation, amalgamation or merger where the Partnership is not the continuing Person, or disposition of all or substantially all of the assets of the Partnership in accordance with Section 10.01, the Successor Partnership shall succeed to and be substituted for the Partnership with the same effect as if it had been named herein as the respective party to this Indenture, and the predecessor entity shall be released from all liabilities and obligations under this Indenture and the Debt Securities, except that no such release will occur in the case of a lease of all or substantially all of the Partnership's assets. The Successor Partnership thereupon may cause to be signed, and may issue either in its own name or in the name of the Partnership, any or all the Debt Securities issuable hereunder which theretofore shall not have been signed by or on behalf of the Partnership and delivered to the Trustee; and, upon the order of the Successor Partnership, instead of the Partnership, and subject to all the terms, conditions and limitations in this Indenture prescribed, the Trustee shall authenticate and shall deliver any Debt Securities which previously shall have been signed and delivered by or on behalf of the Partnership to the Trustee for authentication, and any Debt Securities which the Successor Partnership thereafter shall

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cause to be signed and delivered to the Trustee for that purpose. All the Debt Securities so issued shall in all respects have the same legal rank and benefit under this Indenture as the Debt Securities theretofore or thereafter issued in accordance with the terms of this Indenture as though all such Debt Securities had been issued at the date of the execution hereof.

        In case of any such consolidation, amalgamation, merger, sale or disposition such changes in phraseology and form (but not in substance) may be made in the Debt Securities thereafter to be issued as may be appropriate.

ARTICLE XI

SATISFACTION AND DISCHARGE OF
INDENTURE; DEFEASANCE; UNCLAIMED MONEYS

        Section 11.01 Applicability of Article. The provisions of this Article XI relating to discharge or defeasance of Debt Securities shall be applicable to each series of Debt Securities except as otherwise specified pursuant to Section 2.03 for Debt Securities of such series.

        Section 11.02 Satisfaction and Discharge of Indenture; Defeasance.

        (a)   If at any time the Partnership shall have delivered to the Trustee for cancellation all Debt Securities of any series theretofore authenticated and delivered (other than any Debt Securities of such series which shall have been destroyed, lost or stolen and which shall have been replaced or paid as provided in Section 2.09 and Debt Securities for whose payment money has theretofore been deposited in trust and thereafter repaid to the Partnership as provided in Section 11.05) or all Debt Securities of such series not theretofore delivered to the Trustee for cancellation shall have become due and payable, or are by their terms to become due and payable within one year or are to be called for redemption within one year under arrangements satisfactory to the Trustee for the giving of notice of redemption, and the Partnership shall deposit with the Trustee as trust funds the entire amount in cash sufficient to pay at final maturity or upon redemption all Debt Securities of such series not theretofore delivered to the Trustee for cancellation, including principal and premium, if any, and interest due or to become due on such date of maturity or Redemption Date, as the case may be, and if in either case the Partnership shall also pay or cause to be paid all other sums payable hereunder by the Partnership, then this Indenture shall cease to be of further effect (except as to any surviving rights of registration of transfer or exchange of such Debt Securities herein expressly provided for) with respect to the Debt Securities of such series, and the Trustee, on demand of the Partnership accompanied by an Officers' Certificate and an Opinion of Counsel and at the cost and expense of the Partnership, shall execute proper instruments acknowledging satisfaction of and discharging this Indenture with respect to the Debt Securities of such series.

        (b)   Subject to Sections 11.02(c), 11.03 and 11.07, the Partnership at any time may terminate, with respect to Debt Securities of a particular series, all its obligations under the Debt Securities of such series and this Indenture with respect to the Debt Securities of such series ("legal defeasance option") or the operation of (w) Sections 4.09 and 4.10, (x) any covenant made applicable to such Debt Securities pursuant to Section 2.03, (y) Sections 6.01(d), (g) and (h) and (z) as they relate to the Subsidiary Guarantors only, Sections 6.01(e) and (f) ("covenant defeasance option"). If the Partnership exercises either its legal defeasance option or its covenant defeasance option with respect to Debt Securities of a particular series that are entitled to the benefit of the Guarantee, the Guarantee will terminate with respect to that series of Debt Securities. The Partnership may exercise its legal defeasance option notwithstanding its prior exercise of its covenant defeasance option.

        If the Partnership exercises its legal defeasance option, payment of the Debt Securities of the defeased series may not be accelerated because of an Event of Default. If the Partnership exercises its covenant defeasance option, payment of the Debt Securities of the defeased series may not be

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accelerated because of an Event of Default specified in Sections 6.01(d), (g) and (h) and, with respect to the Subsidiary Guarantors only, Sections 6.01(e) and (f).

        Upon satisfaction of the conditions set forth herein and upon request of the Partnership, the Trustee shall acknowledge in writing the discharge of those obligations that the Partnership terminates.

        (c)   Notwithstanding clauses (a) and (b) above, the Partnership's obligations in Sections 2.07, 2.09, 4.02, 4.03, 4.04, the last sentence of 4.05(a), 4.06(a), 5.01, 7.06, 11.05, 11.06 and 11.07 shall survive until the Debt Securities of the defeased series have been paid in full. Thereafter, the Partnership's obligations in Sections 7.06, 11.05 and 11.06 shall survive.

        (d)   Conditions of Defeasance.    The Partnership may exercise its legal defeasance option or its covenant defeasance option with respect to Debt Securities of a particular series only if:

        (e)   the Partnership irrevocably deposits in trust with the Trustee money or U.S. Government Obligations for the payment of principal of, and premium, if any, and interest on, the Debt Securities of such series to final maturity or redemption, as the case may be;

        (f)    the Partnership delivers to the Trustee a certificate from a nationally recognized firm of independent accountants expressing their opinion that the payments of principal and interest when due and without reinvestment on the deposited U.S. Government Obligations plus any deposited money without investment will provide cash at such times and in such amounts as will be sufficient to pay the principal, premium, if any, and interest when due on all the Debt Securities of such series to final maturity or redemption, as the case may be;

        (g)   91 days pass after the deposit is made and during the 91-day period no Default specified in Section 6.01(e) or (f) with respect to the Partnership occurs which is continuing at the end of the period;

        (h)   no Default has occurred and is continuing on the date of such deposit and after giving effect thereto;

        (i)    the deposit does not constitute a default under any other agreement binding on the Partnership and, if the Debt Securities of such series are subordinated pursuant to Article XII, is not prohibited by Article XII;

        (j)    the Partnership delivers to the Trustee an Opinion of Counsel to the effect that the trust resulting from the deposit does not constitute, or is qualified as, a regulated investment company under the Investment Partnership Act of 1940;

        (k)   in the event of the legal defeasance option, the Partnership shall have delivered to the Trustee an Opinion of Counsel stating that the Partnership has received from the Internal Revenue Service a ruling, or since the date of this Indenture there has been a change in the applicable Federal income tax law, in either case to the effect that, and based thereon such Opinion of Counsel shall confirm that, the Holders of Debt Securities of such series will not recognize income, gain or loss for Federal income tax purposes as a result of such defeasance and will be subject to Federal income tax on the same amounts, in the same manner and at the same times as would have been the case if such defeasance had not occurred;

        (l)    in the event of the covenant defeasance option, the Partnership shall have delivered to the Trustee an Opinion of Counsel to the effect that the Holders of Debt Securities of such series will not recognize income, gain or loss for Federal income tax purposes as a result of such covenant defeasance and will be subject to Federal income tax on the same amounts, in the same manner and at the same times as would have been the case if such covenant defeasance had not occurred; and

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        (m)  the Partnership delivers to the Trustee an Officers' Certificate and an Opinion of Counsel, each stating that all conditions precedent to the defeasance and discharge of the Debt Securities of such series as contemplated by this Article XI have been complied with.

        Before or after a deposit, the Partnership may make arrangements satisfactory to the Trustee for the redemption of Debt Securities of such series at a future date in accordance with Article III.

        Section 11.03 Application of Trust Money. The Trustee shall hold in trust money or U.S. Government Obligations deposited with it pursuant to this Article XI. It shall apply the deposited money and the money from U.S. Government Obligations through any paying agent and in accordance with this Indenture to the payment of principal of, and premium, if any, and interest on, the Debt Securities of the defeased series. In the event the Debt Securities of the defeased series are subordinated pursuant to Article XII, money and securities so held in trust are not subject to Article XII.

        Section 11.04 Repayment to Partnership. The Trustee and any paying agent shall promptly turn over to the Partnership upon request any excess money or securities held by them at any time.

        Subject to any applicable abandoned property law, the Trustee and any paying agent shall pay to the Partnership upon request any money held by them for the payment of principal, premium or interest that remains unclaimed for two years, and, thereafter, Holders entitled to such money must look to the Partnership for payment as general creditors.

        Section 11.05 Indemnity for U.S. Government Obligations. The Partnership shall pay and shall indemnify the Trustee and the Holders against any tax, fee or other charge imposed on or assessed against deposited U.S. Government Obligations or the principal and interest received on such U.S. Government Obligations.

        Section 11.06 Reinstatement. If the Trustee or any paying agent is unable to apply any money or U.S. Government Obligations in accordance with this Article XI by reason of any legal proceeding or by reason of any order or judgment of any court or government authority enjoining, restraining or otherwise prohibiting such application, the Partnership's obligations under this Indenture and the Debt Securities of the defeased series shall be revived and reinstated as though no deposit had occurred pursuant to this Article XI until such time as the Trustee or any paying agent is permitted to apply all such money or U.S. Government Obligations in accordance with this Article XI.

ARTICLE XII

SUBORDINATION OF DEBT SECURITIES AND GUARANTEE

        Section 12.01 Applicability of Article; Agreement to Subordinate. The provisions of this Article XII shall only be applicable to the Debt Securities of any series (Debt Securities of such series referred to in this Article XII as "Subordinated Debt Securities") designated, pursuant to Section 2.03, as subordinated to Senior Indebtedness and any related Guarantee of such Subordinated Debt Securities. Each Holder by accepting a Subordinated Debt Security agrees that the Debt evidenced by such Subordinated Debt Security and any related Guarantee of such Subordinated Debt Security is subordinated in right of payment, to the extent and in the manner provided in this Article XII, to the prior payment of all Senior Indebtedness and that the subordination is for the benefit of and enforceable by the holders of Senior Indebtedness. All provisions of this Article XII shall be subject to Section 12.12.

        Section 12.02 Liquidation, Dissolution, Bankruptcy. Upon any payment or distribution of the assets of the Partnership or the Subsidiary Guarantors, as the case may be, to creditors, upon a liquidation or a dissolution of the Partnership or the Subsidiary Guarantors, as the case may be, or in a bankruptcy,

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reorganization, insolvency, receivership or similar proceeding relating to the Partnership or the Subsidiary Guarantors, as the case may be, or their respective property:

        (a)   (holders of Senior Indebtedness of the Partnership or any Subsidiary Guarantor, as the case may be, shall be entitled to receive payment in full in cash of such Senior Indebtedness of such Person (including interest (if any), accruing on or after the commencement of a proceeding in bankruptcy, whether or not allowed as a claim against the Partnership or the Subsidiary Guarantors, as the case may be, in such bankruptcy proceeding) before Holders of Subordinated Debt Securities and any related Guarantee shall be entitled to receive any payment of principal of, or premium, if any, or interest on, the Subordinated Debt Securities from the Partnership, or any payment in respect of the Guarantee from the Subsidiary Guarantors; and

        (b)   until the Senior Indebtedness of the Partnership or any Subsidiary Guarantor, as the case may be, is paid in full, any distribution to which Holders of Subordinated Debt Securities and any related Guarantee would be entitled but for this Article XII shall be made to holders of Senior Indebtedness of the Partnership or the Subsidiary Guarantors, as the case may be, as their interests may appear, except that such Holders may receive capital stock and any debt securities that are subordinated to Senior Indebtedness of the Partnership or the Subsidiary Guarantors, as the case may be, to at least the same extent as the Subordinated Debt Securities of the Partnership or the related Guarantee of any Subsidiary Guarantor, respectively.

        Section 12.03 Default on Senior Indebtedness. The Partnership and the Subsidiary Guarantors may not pay the principal of, or premium, if any, or interest on, the Subordinated Debt Securities or any related Guarantee or make any deposit pursuant to Article XI and may not repurchase, redeem or otherwise retire (except, in the case of Subordinated Debt Securities that provide for a mandatory sinking fund pursuant to Section 3.05, by the delivery of Subordinated Debt Securities by the Partnership to the Trustee pursuant to the first paragraph of Section 3.05) any Subordinated Debt Securities (collectively, "pay the Subordinated Debt Securities") if any principal, premium or interest in respect of Senior Indebtedness of such Person is not paid within any applicable grace period (including at maturity) or any other default on Senior Indebtedness of such Person occurs and the maturity of such Senior Indebtedness is accelerated in accordance with its terms unless, in either case, the default has been cured or waived and any such acceleration has been rescinded or such Senior Indebtedness has been paid in full in cash; provided, however, that the Partnership and the Subsidiary Guarantors may make payments on the Subordinated Debt Securities or any related Guarantee without regard to the foregoing if the Partnership and the Trustee receive written notice approving such payment from the Representative of each issue of Designated Senior Indebtedness. During the continuance of any other default with respect to any Designated Senior Indebtedness pursuant to which the maturity thereof may be accelerated immediately without further notice (except such notice as may be required to effect such acceleration) or the expiration of any applicable grace periods, the Partnership and the Subsidiary Guarantors may not make payments on the Subordinated Debt Securities or any related Guarantee for a period (a "Payment Blockage Period") commencing upon the receipt by the Partnership and the Trustee (and if such Designated Senior Indebtedness is Debt of a Subsidiary Guarantor, the Subsidiary Guarantor) of written notice of such default from the Representative of any Designated Senior Indebtedness specifying an election to effect a Payment Blockage Period (a "Blockage Notice") and ending 179 days thereafter (or earlier if such Payment Blockage Period is terminated by written notice to the Trustee and the Partnership (and if such Designated Senior Indebtedness is Debt of a Subsidiary Guarantor, the Subsidiary Guarantor) from the Person or Persons who gave such Blockage Notice, by repayment in full in cash of such Designated Senior Indebtedness or because the default giving rise to such Blockage Notice is no longer continuing). Notwithstanding the provisions described in the immediately preceding sentence (but subject to the provisions contained in Section 12.02 and the first sentence of this Section 12.03), unless the holders of such Designated Senior Indebtedness or the Representative of such holders shall have accelerated the maturity of such

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Designated Senior Indebtedness, the Partnership and the Subsidiary Guarantors may resume payments on the Subordinated Debt Securities and related Guarantees after such Payment Blockage Period. Not more than one Blockage Notice may be given in any consecutive 360-day period, irrespective of the number of defaults with respect to any number of issues of Designated Senior Indebtedness during such period, unless otherwise specified pursuant to Section 2.03 for the Subordinated Debt Securities of a series; provided, however, that in no event may the total number of days during which any Payment Blockage Period or Periods is in effect exceed 179 days in the aggregate during any 360 consecutive day period. For purposes of this Section 12.03, no default or event of default which existed or was continuing on the date of the commencement of any Payment Blockage Period with respect to the Designated Senior Indebtedness initiating such Payment Blockage Period shall be, or be made, the basis of the commencement of a subsequent Payment Blockage Period by the Representative of such Designated Senior Indebtedness, whether or not within a period of 360 consecutive days, unless such default or event of default shall have been cured or waived for a period of not less than 90 consecutive days.

        Section 12.04 Acceleration of Payment of Debt Securities. If payment of the Subordinated Debt Securities is accelerated because of an Event of Default, the Partnership shall promptly notify the holders of the Designated Senior Indebtedness (or their Representatives) of the acceleration.

        Section 12.05 When Distribution Must Be Paid Over. If a distribution is made to Holders of Subordinated Debt Securities or a related Guarantee that because of this Article XII should not have been made to them, the Holders who receive such distribution shall hold it in trust for holders of Senior Indebtedness and pay it over to them as their interests may appear.

        Section 12.06 Subrogation. After all Senior Indebtedness is paid in full and until the Subordinated Debt Securities are paid in full, Holders thereof shall be subrogated to the rights of holders of Senior Indebtedness to receive distributions applicable to Senior Indebtedness. A distribution made under this Article XII to holders of Senior Indebtedness which otherwise would have been made to Holders of Subordinated Debt Securities is not, as between the Partnership or the Subsidiary Guarantors, as the case may be, and such Holders, a payment by the Partnership or the Subsidiary Guarantors, as the case may be, on Senior Indebtedness.

        Section 12.07 Relative Rights. This Article XII defines the relative rights of Holders of Subordinated Debt Securities and holders of Senior Indebtedness. Nothing in this Indenture shall:

        (a)   impair, as between the Partnership or the Subsidiary Guarantors, as the case may be, and Holders of Subordinated Debt Securities, the obligation of the Partnership or the Subsidiary Guarantors, as the case may be, which is absolute and unconditional, to pay principal of, and premium, if any, and interest on, the Subordinated Debt Securities in accordance with their terms; or

        (b)   prevent the Trustee or any Holder of Subordinated Debt Securities from exercising its available remedies upon an Event of Default, subject to the rights of holders of Senior Indebtedness to receive distributions otherwise payable to Holders of Subordinated Debt Securities.

        Section 12.08 Subordination May Not Be Impaired by Partnership. No right of any holder of Senior Indebtedness to enforce the subordination of the Debt evidenced by the Subordinated Debt Securities and the Guarantee in respect thereof shall be impaired by any act or failure to act by the Partnership or the Subsidiary Guarantors or by its failure to comply with this Indenture.

        Section 12.09 Rights of Trustee and Paying Agent. Notwithstanding Sections 12.02 and 12.03, the Trustee or any paying agent may continue to make payments on Subordinated Debt Securities and shall not be charged with knowledge of the existence of facts that would prohibit the making of any such payments unless, not less than two Business Days prior to the date of such payment, a responsible officer of the Trustee receives notice satisfactory to it that payments may not be made under this Article XII. The Partnership, the Registrar, any paying agent, a Representative or a holder of Senior Indebtedness may give the notice; provided, however, that, if an issue of Senior Indebtedness has a Representative, only the Representative may give the notice on behalf of the Holders of the Senior Indebtedness of that issue.

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        The Trustee in its individual or any other capacity may hold Senior Indebtedness with the same rights it would have if it were not Trustee. The Registrar and any paying agent may do the same with like rights. The Trustee shall be entitled to all the rights set forth in this Article XII with respect to any Senior Indebtedness which may at any time be held by it, to the same extent as any other holder of Senior Indebtedness; and nothing in Article VII shall deprive the Trustee of any of its rights as such holder. Nothing in this Article XII shall apply to claims of, or payments to, the Trustee under or pursuant to Section 7.06.

        Section 12.10 Distribution or Notice to Representative. Whenever a distribution is to be made or a notice given to holders of Senior Indebtedness, the distribution may be made and the notice given to their Representative (if any).

        Section 12.11 Article XII Not to Prevent Defaults or Limit Right to Accelerate. The failure to make a payment pursuant to the Subordinated Debt Securities, whether directly or pursuant to the Guarantee, by reason of any provision in this Article XII shall not be construed as preventing the occurrence of a Default. Nothing in this Article XII shall have any effect on the right of the Holders or the Trustee to accelerate the maturity of either the Subordinated Debt Securities or the Debt Securities, as the case may be.

        Section 12.12 Trust Moneys Not Subordinated. Notwithstanding anything contained herein to the contrary, payments from money or the proceeds of U.S. Government Obligations held in trust under Article XI by the Trustee for the payment of principal of, and premium, if any, and interest on, the Subordinated Debt Securities or the Debt Securities shall not be subordinated to the prior payment of any Senior Indebtedness or subject to the restrictions set forth in this Article XII, and none of the Holders thereof shall be obligated to pay over any such amount to the Partnership, the Subsidiary Guarantors or any holder of Senior Indebtedness of the Partnership or the Subsidiary Guarantors or any other creditor of the Partnership or the Guarantor.

        Section 12.13 Trustee Entitled to Rely. Upon any payment or distribution pursuant to this Article XII, the Trustee and the Holders shall be entitled to rely upon any order or decree of a court of competent jurisdiction in which any proceedings of the nature referred to in Section 12.02 are pending, upon a certificate of the liquidating trustee or agent or other Person making such payment or distribution to the Trustee or to such Holders or upon the Representatives for the holders of Senior Indebtedness for the purpose of ascertaining the Persons entitled to participate in such payment or distribution, the holders of the Senior Indebtedness and other Debt of the Partnership or the Subsidiary Guarantors, the amount thereof or payable thereon, the amount or amounts paid or distributed thereon and all other facts pertinent thereto or to this Article XII. In the event that the Trustee determines, in good faith, that evidence is required with respect to the right of any Person as a holder of Senior Indebtedness to participate in any payment or distribution pursuant to this Article XII, the Trustee may request such Person to furnish evidence to the reasonable satisfaction of the Trustee as to the amount of Senior Indebtedness held by such Person, the extent to which such Person is entitled to participate in such payment or distribution and other facts pertinent to the rights of such Person under this Article XII, and, if such evidence is not furnished, the Trustee may defer any payment to such Person pending judicial determination as to the right of such Person to receive such payment. The provisions of Sections 7.01 and 7.02 shall be applicable to all actions or omissions of actions by the Trustee pursuant to this Article XII.

        Section 12.14 Trustee to Effectuate Subordination. Each Holder by accepting a Subordinated Debt Security authorizes and directs the Trustee on his behalf to take such action as may be necessary or appropriate to acknowledge or effectuate the subordination between the Holders of Subordinated Debt Securities and the holders of Senior Indebtedness as provided in this Article XII and appoints the Trustee as attorney-in-fact for any and all such purposes.

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        Section 12.15 Trustee Not Fiduciary for Holders of Senior Indebtedness. The Trustee shall not be deemed to owe any fiduciary duty to the holders of Senior Indebtedness and shall not be liable to any such holders if it shall mistakenly pay over or distribute to Holders of Subordinated Debt Securities or the Partnership or the Subsidiary Guarantors or any other Person, money or assets to which any holders of Senior Indebtedness shall be entitled by virtue of this Article XII or otherwise.

        Section 12.16 Reliance by Holders of Senior Indebtedness on Subordination Provisions. Each Holder by accepting a Subordinated Debt Security acknowledges and agrees that the foregoing subordination provisions are, and are intended to be, an inducement and a consideration to each holder of any Senior Indebtedness, whether such Senior Indebtedness was created or acquired before or after the issuance of the Subordinated Debt Securities, to acquire and continue to hold, or to continue to hold, such Senior Indebtedness and such holder of Senior Indebtedness shall be deemed conclusively to have relied on such subordination provisions in acquiring and continuing to hold, or in continuing to hold, such Senior Indebtedness.

ARTICLE XIII

MISCELLANEOUS PROVISIONS

        Section 13.01 Successors and Assigns of Partnership Bound by Indenture. All the covenants, stipulations, promises and agreements in this Indenture contained by or in behalf of the Partnership, the Subsidiary Guarantors or the Trustee shall bind their respective successors and assigns, whether so expressed or not.

        Section 13.02 Acts of Board, Committee or Officer of Successor Partnership Valid. Any act or proceeding by any provision of this Indenture authorized or required to be done or performed by any board, committee or officer of the Partnership shall and may be done and performed with like force and effect by the like board, committee or officer of any Successor Partnership.

        Section 13.03 Required Notices or Demands. Any notice or communication by the Partnership, the Subsidiary Guarantors or the Trustee to the others is duly given if in writing and delivered in Person or mailed by registered or certified mail (return receipt requested), telecopier or overnight air courier guaranteeing next day delivery, to the other's address:

        If to the Partnership or any Subsidiary Guarantor:

MarkWest Energy Partners, L.P.
1515 Arapahoe Street
Tower 2, Suite 700
Denver, Colorado 80202
Attention: Andrew L. Schroeder

        If to the Trustee:

[            ]

        The Partnership, any Subsidiary Guarantor or the Trustee by notice to the others may designate additional or different addresses for subsequent notices or communications.

        All notices and communications shall be deemed to have been duly given: at the time delivered by hand, if personally delivered; five Business Days after being deposited in the mail, postage prepaid, if mailed; on the first Business Day on or after being sent, if telecopied and the sender receives confirmation of successful transmission; and the next Business Day after timely delivery to the courier, if sent by overnight air courier guaranteeing next day delivery.

        Any notice required or permitted to a Holder by the Partnership, any Subsidiary Guarantor or the Trustee pursuant to the provisions of this Indenture shall be deemed to be properly mailed by being

47

deposited postage prepaid in a post office letter box in the United States addressed to such Holder at the address of such Holder as shown on the Debt Security Register. Any report pursuant to Section 313 of the TIA shall be transmitted in compliance with subsection (c) therein.

        Notwithstanding the foregoing, any notice to Holders of Floating Rate Securities regarding the determination of a periodic rate of interest, if such notice is required pursuant to Section 2.03, shall be sufficiently given if given in the manner specified pursuant to Section 2.03.

        In the event of suspension of regular mail service or by reason of any other cause it shall be impracticable to give notice by mail, then such notification as shall be given with the approval of the Trustee shall constitute sufficient notice for every purpose hereunder.

        In the event it shall be impracticable to give notice by publication, then such notification as shall be given with the approval of the Trustee shall constitute sufficient notice for every purpose hereunder.

        Failure to mail a notice or communication to a Holder or any defect in it or any defect in any notice by publication as to a Holder shall not affect the sufficiency of such notice with respect to other Holders. If a notice or communication is mailed or published in the manner provided above, it is conclusively presumed duly given.

        Section 13.04 Indenture and Debt Securities to Be Construed in Accordance with the Laws of the State of New York. THIS INDENTURE, EACH DEBT SECURITY AND THE GUARANTEE SHALL BE DEEMED TO BE NEW YORK CONTRACTS, AND FOR ALL PURPOSES SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF SAID STATE.

        Section 13.05 Officers' Certificate and Opinion of Counsel to Be Furnished upon Application or Demand by the Partnership. Upon any application or demand by the Partnership to the Trustee to take any action under any of the provisions of this Indenture, the Partnership shall furnish to the Trustee an Officers' Certificate stating that all conditions precedent provided for in this Indenture relating to the proposed action have been complied with and an Opinion of Counsel stating that, in the opinion of such counsel, all such conditions precedent have been complied with, except that in the case of any such application or demand as to which the furnishing of such document is specifically required by any provision of this Indenture relating to such particular application or demand, no additional certificate or opinion need be furnished.

        Each certificate or opinion provided for in this Indenture and delivered to the Trustee with respect to compliance with a condition or covenant provided for in this Indenture shall include (a) a statement that the Person making such certificate or opinion has read such covenant or condition, (b) a brief statement as to the nature and scope of the examination or investigation upon which the statements or opinions contained in such certificate or opinion are based, (c) a statement that, in the opinion of such Person, he has made such examination or investigation as is necessary to enable him to express an informed opinion as to whether or not such covenant or condition has been complied with and (d) a statement as to whether or not, in the opinion of such Person, such condition or covenant has been complied with.

        Section 13.06 Payments Due on Legal Holidays. In any case where the date of maturity of interest on or principal of and premium, if any, on the Debt Securities of a series or the date fixed for redemption or repayment of any Debt Security or the making of any sinking fund payment shall not be a Business Day at any Place of Payment for the Debt Securities of such series, then payment of interest or principal and premium, if any, or the making of such sinking fund payment need not be made on such date at such Place of Payment, but may be made on the next succeeding Business Day at such Place of Payment with the same force and effect as if made on the date of maturity or the date fixed for redemption, and no interest shall accrue for the period after such date. If a record date is not a Business Day, the record date shall not be affected.

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        Section 13.07 Provisions Required by TIA to Control. If and to the extent that any provision of this Indenture limits, qualifies or conflicts with another provision included in this Indenture which is required to be included in this Indenture by any of Sections 310 to 318, inclusive, of the TIA, such required provision shall control.

        Section 13.08 Computation of Interest on Debt Securities. Interest, if any, on the Debt Securities shall be computed on the basis of a 360-day year of twelve 30-day months, except as may otherwise be provided pursuant to Section 2.03.

        Section 13.09 Rules by Trustee, Paying Agent and Registrar. The Trustee may make reasonable rules for action by or a meeting of Holders. The Registrar and any paying agent may make reasonable rules for their functions.

        Section 13.10 No Recourse Against Others. The Partnership and its directors, officers, employees, incorporators and capital stockholders, as such, shall have no liability for any obligations of the Subsidiary Guarantors or the Partnership under the Debt Securities, this Indenture or the Guarantee or for any claim based on, in respect of, or by reason of, such obligations or their creation. By accepting a Debt Security, each Holder shall be deemed to have waived and released all such liability. The waiver and release shall be part of the consideration for the issue of the Debt Securities.

        Section 13.11 Severability. In case any provision in this Indenture or the Debt Securities shall be invalid, illegal or unenforceable, the validity, legality and enforceability of the remaining provisions shall not in any way be affected or impaired thereby.

        Section 13.12 Effect of Headings. The article and section headings herein and in the Table of Contents are for convenience only and shall not affect the construction hereof.

        Section 13.13 Indenture May Be Executed in Counterparts. This Indenture may be executed in any number of counterparts, each of which shall be an original; but such counterparts shall together constitute but one and the same instrument.

ARTICLE XIV

GUARANTEE

        Section 14.01 Unconditional Guarantee.

        (a)   Notwithstanding any provision of this Article XIV to the contrary, the provisions of this Article XIV shall be applicable only to, and inure solely to the benefit of, the Debt Securities of any series designated, pursuant to Section 2.03, as entitled to the benefits of the Guarantee of each of the Subsidiary Guarantors.

        (b)   For value received, each of the Subsidiary Guarantors hereby fully, unconditionally and absolutely guarantees (the "Guarantee") to the Holders and to the Trustee the due and punctual payment of the principal of, and premium, if any, and interest on the Debt Securities and all other amounts due and payable under this Indenture and the Debt Securities by the Partnership, when and as such principal, premium, if any, and interest shall become due and payable, whether at the Stated Maturity or by declaration of acceleration, call for redemption or otherwise, according to the terms of the Debt Securities and this Indenture, subject to (i) the limitations set forth in Section 14.03 and (ii) in the case of the Guarantee of the Subordinated Debt Securities, to the subordination provisions contained in Article XII.

        (c)   Failing payment when due of any amount guaranteed pursuant to the Guarantee, for whatever reason, each of the Subsidiary Guarantors will be jointly and severally obligated to pay the same immediately, subject, in the case of the Guarantee of the Subordinated Debt Securities, to the subordination provisions contained in Article XII. The Guarantee hereunder (other than the Guarantee

49

of Subordinated Debt Securities) is intended to be a general, unsecured, senior obligation of each of the Subsidiary Guarantors and will rank pari passu in right of payment with all Debt of each Subsidiary Guarantor that is not, by its terms, expressly subordinated in right of payment to the Guarantee. Each of the Subsidiary Guarantors hereby agrees that its obligations hereunder shall be full, unconditional and absolute, irrespective of the validity, regularity or enforceability of the Debt Securities, the Guarantee (including the Guarantee of any other Subsidiary Guarantor) or this Indenture, the absence of any action to enforce the same, any waiver or consent by any Holder of the Debt Securities with respect to any provisions hereof or thereof, the recovery of any judgment against the Partnership or any other Subsidiary Guarantor, or any action to enforce the same or any other circumstances which might otherwise constitute a legal or equitable discharge or defense of any of the Subsidiary Guarantors. Each of the Subsidiary Guarantors hereby agrees that in the event of a default in payment of the principal of, or premium, if any, or interest on the Debt Securities, whether at the Stated Maturity or by declaration of acceleration, call for redemption or otherwise, legal proceedings may be instituted by the Trustee on behalf of the Holders or, subject to Section 6.04, by the Holders, on the terms and conditions set forth in this Indenture, directly against such Subsidiary Guarantor to enforce the Guarantee without first proceeding against the Partnership or any other Subsidiary Guarantor.

        (d)   The obligations of each of the Subsidiary Guarantors under this Article XIV shall be as aforesaid full, unconditional and absolute and shall not be impaired, modified, released or limited by any occurrence or condition whatsoever, including, without limitation, (A) any compromise, settlement, release, waiver, renewal, extension, indulgence or modification of, or any change in, any of the obligations and liabilities of the Partnership or any of the Subsidiary Guarantors contained in the Debt Securities or this Indenture, (B) any impairment, modification, release or limitation of the liability of the Partnership, any of the Subsidiary Guarantors or any of their estates in bankruptcy, or any remedy for the enforcement thereof, resulting from the operation of any present or future provision of any applicable Bankruptcy Law, as amended, or other statute or from the decision of any court, (C) the assertion or exercise by the Partnership, any of the Subsidiary Guarantors or the Trustee of any rights or remedies under the Debt Securities or this Indenture or their delay in or failure to assert or exercise any such rights or remedies, (D) the assignment or the purported assignment of any property as security for the Debt Securities, including all or any part of the rights of the Partnership or any of the Subsidiary Guarantors under this Indenture, (E) the extension of the time for payment by the Partnership or any of the Subsidiary Guarantors of any payments or other sums or any part thereof owing or payable under any of the terms and provisions of the Debt Securities or this Indenture or of the time for performance by the Partnership or any of the Subsidiary Guarantors of any other obligations under or arising out of any such terms and provisions or the extension or the renewal of any thereof, (F) the modification or amendment (whether material or otherwise) of any duty, agreement or obligation of the Partnership or any of the Subsidiary Guarantors set forth in this Indenture, (G) the voluntary or involuntary liquidation, dissolution, sale or other disposition of all or substantially all of the assets, marshaling of assets and liabilities, receivership, insolvency, bankruptcy, assignment for the benefit of creditors, reorganization, arrangement, composition or readjustment of, or other similar proceeding affecting, the Partnership or any of the Subsidiary Guarantors or any of their respective assets, or the disaffirmance of the Debt Securities, the Guarantee or this Indenture in any such proceeding, (H) the release or discharge of the Partnership or any of the Subsidiary Guarantors from the performance or observance of any agreement, covenant, term or condition contained in any of such instruments by operation of law, (I) the unenforceability of the Debt Securities, the Guarantee or this Indenture or (J) any other circumstances (other than payment in full or discharge of all amounts guaranteed pursuant to the Guarantee) which might otherwise constitute a legal or equitable discharge of a surety or guarantor.

        (e)   Each of the Subsidiary Guarantors hereby (A) waives diligence, presentment, demand of payment, filing of claims with a court in the event of the merger, insolvency or bankruptcy of the Partnership or any of the Subsidiary Guarantors, and all demands whatsoever, (B) acknowledges that

50

any agreement, instrument or document evidencing the Guarantee may be transferred and that the benefit of its obligations hereunder shall extend to each holder of any agreement, instrument or document evidencing the Guarantee without notice to it and (C) covenants that the Guarantee will not be discharged except by complete performance of the Guarantee. Each of the Subsidiary Guarantors further agrees that if at any time all or any part of any payment theretofore applied by any Person to the Guarantee is, or must be, rescinded or returned for any reason whatsoever, including without limitation, the insolvency, bankruptcy or reorganization of the Partnership or any of the Subsidiary Guarantors, the Guarantee shall, to the extent that such payment is or must be rescinded or returned, be deemed to have continued in existence notwithstanding such application, and the Guarantee shall continue to be effective or be reinstated, as the case may be, as though such application had not been made.

        (f)    Each of the Subsidiary Guarantors shall be subrogated to all rights of the Holders and the Trustee against the Partnership in respect of any amounts paid by such Subsidiary Guarantor pursuant to the provisions of this Indenture, provided, however, that such Subsidiary Guarantor, shall not be entitled to enforce or to receive any payments arising out of, or based upon, such right of subrogation until all of the Debt Securities and the Guarantee shall have been paid in full or discharged.

        Section 14.02 Execution and Delivery of Guarantee. To further evidence the Guarantee set forth in Section 14.01, each of the Subsidiary Guarantors hereby agrees that a notation relating to such Guarantee, substantially in the form attached hereto as Annex A, shall be endorsed on each Debt Security entitled to the benefits of the Guarantee authenticated and delivered by the Trustee and executed by either manual or facsimile signature of an officer of such Subsidiary Guarantor, or in the case of a Subsidiary Guarantor that is a limited Partnership, an officer of the Partnership of each Subsidiary Guarantor. Each of the Subsidiary Guarantors hereby agrees that the Guarantee set forth in Section 14.01 shall remain in full force and effect notwithstanding any failure to endorse on each Debt Security a notation relating to the Guarantee. If any officer of any Subsidiary Guarantor, or in the case of a Subsidiary Guarantor that is a limited Partnership, any officer of the Partnership of the Subsidiary Guarantor, whose signature is on this Indenture or a Debt Security no longer holds that office at the time the Trustee authenticates such Debt Security or at any time thereafter, the Guarantee of such Debt Security shall be valid nevertheless. The delivery of any Debt Security by the Trustee, after the authentication thereof hereunder, shall constitute due delivery of the Guarantee set forth in this Indenture on behalf of the Subsidiary Guarantors.

        The Trustee hereby accepts the trusts in this Indenture upon the terms and conditions herein set forth.

        Section 14.03 Limitation on Subsidiary Guarantors' Liability.

        (a)   Each Subsidiary Guarantor and by its acceptance hereof each Holder of a Debt Security entitled to the benefits of the Guarantee hereby confirm that it is the intention of all such parties that the guarantee by such Subsidiary Guarantor pursuant to the Guarantee not constitute a fraudulent transfer or conveyance for purposes of any Federal or state law. To effectuate the foregoing intention, the Holders of a Debt Security entitled to the benefits of the Guarantee and the Subsidiary Guarantors hereby irrevocably agree that the obligations of each Subsidiary Guarantor under the Guarantee shall be limited to the maximum amount as will, after giving effect to all other contingent and fixed liabilities of such Subsidiary Guarantor and to any collections from or payments made by or on behalf of any other Subsidiary Guarantor in respect of the obligations of such other Subsidiary Guarantor under the Guarantee, not result in the obligations of such Subsidiary Guarantor under the Guarantee constituting a fraudulent conveyance or fraudulent transfer under Federal or state law.

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        Section 14.04 Release of Subsidiary Guarantors from Guarantee.

        (a)   Notwithstanding any other provisions of this Indenture, the Guarantee of any Subsidiary Guarantor may be released upon the terms and subject to the conditions set forth in Section 11.02(b) and in this Section 14.04. Provided that no Default shall have occurred and shall be continuing under this Indenture, the Guarantee incurred by a Subsidiary Guarantor pursuant to this Article XIV shall be unconditionally released and discharged (i) automatically upon (A) any sale, exchange or transfer, whether by way of merger or otherwise, to any Person that is not an Affiliate of the Partnership, of all of the Partnership's direct or indirect limited Partnership or other equity interests in such Subsidiary Guarantor (provided such sale, exchange or transfer is not prohibited by this Indenture) or (B) the merger of such Subsidiary Guarantor into the Partnership or any other Subsidiary Guarantor or the liquidation and dissolution of such Subsidiary Guarantor (in each case to the extent not prohibited by this Indenture) or (ii) following delivery of a written notice of such release or discharge by the Partnership to the Trustee, upon the release or discharge of all guarantees by such Subsidiary Guarantor of any Debt of the Partnership other than obligations arising under this Indenture and any Debt Securities issued hereunder, except a discharge or release by or as a result of payment under such guarantees.

        (b)   The Trustee shall deliver an appropriate instrument evidencing any release of a Subsidiary Guarantor from the Guarantee upon receipt of a written request of the Partnership accompanied by an Officers' Certificate and an Opinion of Counsel to the effect that the Subsidiary Guarantor is entitled to such release in accordance with the provisions of this Indenture. Any Subsidiary Guarantor not so released shall remain liable for the full amount of principal of (and premium, if any) and interest on the Debt Securities entitled to the benefits of the Guarantee as provided in this Indenture, subject to the limitations of Section 14.03.

        Section 14.05 Subsidiary Guarantor Contribution. In order to provide for just and equitable contribution among the Subsidiary Guarantors, the Subsidiary Guarantors hereby agree, inter se, that in the event any payment or distribution is made by any Subsidiary Guarantor (a "Funding Guarantor") under the Guarantee, such Funding Guarantor shall be entitled to a contribution from each other Subsidiary Guarantor (if any) in a pro rata amount based on the net assets of each Subsidiary Guarantor (including the Funding Guarantor) for all payments, damages and expenses incurred by that Funding Guarantor in discharging the Partnership's obligations with respect to the Debt Securities or any other Subsidiary Guarantor's obligations with respect to the Guarantee.

[Remainder of This Page Intentionally Left Blank.]

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        IN WITNESS WHEREOF, the parties hereto have caused this Indenture to be duly executed, all as of the day and year first above written.

MARKWEST ENERGY PARTNERS, L.P.
By:	MarkWest Energy GP, L.L.C., its General Partner
By:
	[            ] Vice President and Chief Financial Officer

[NAME OF SUBSIDIARY GUARANTOR(S)]

By:

Name:

Title:

By:

Name:

Title:

Signature Page to Subordinated Indenture

ANNEX A

NOTATION OF GUARANTEE

        Each of the Subsidiary Guarantors (which term includes any successor Person under the Indenture), has fully, unconditionally and absolutely guaranteed, to the extent set forth in the Indenture and subject to the provisions in the Indenture, the due and punctual payment of the principal of, and premium, if any, and interest on the Debt Securities and all other amounts due and payable under the Indenture and the Debt Securities by the Partnership.

        The obligations of the Subsidiary Guarantors to the Holders of Debt Securities and to the Trustee pursuant to the Guarantee and the Indenture are expressly set forth in Article XIV of the Indenture and reference is hereby made to the Indenture for the precise terms of the Guarantee.

[NAME OF SUBSIDIARY GUARANTOR(S)]

By:

Name:

Title:

Annex A

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Exhibit 4.25

CROSS-REFERENCE TABLE
TABLE OF CONTENTS
RECITALS OF THE COMPANY AND ANY SUBSIDIARY GUARANTORS
ARTICLE I DEFINITIONS AND INCORPORATION BY REFERENCE
ARTICLE II DEBT SECURITIES
TRUSTEE'S CERTIFICATE OF AUTHENTICATION
ARTICLE III REDEMPTION OF DEBT SECURITIES
ARTICLE IV PARTICULAR COVENANTS OF THE COMPANY
ARTICLE V HOLDERS' LISTS AND REPORTS BY THE TRUSTEE
ARTICLE VI REMEDIES OF THE TRUSTEE AND HOLDERS IN EVENT OF DEFAULT
ARTICLE VII CONCERNING THE TRUSTEE
ARTICLE VIII CONCERNING THE HOLDERS
ARTICLE IX SUPPLEMENTAL INDENTURES
ARTICLE X CONSOLIDATION, MERGER, SALE OR CONVEYANCE
ARTICLE XI SATISFACTION AND DISCHARGE OF INDENTURE; DEFEASANCE; UNCLAIMED MONEYS
ARTICLE XII SUBORDINATION OF DEBT SECURITIES AND GUARANTEE
ARTICLE XIII MISCELLANEOUS PROVISIONS
ARTICLE XIV GUARANTEE

ANNEX A

NOTATION OF GUARANTEE

EX-5.1

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Exhibit 5.1

[Vinson & Elkins LLP Letterhead]

January 13, 2010

MarkWest Energy Partners, L.P.
1515 Arapahoe Street
Tower 2, Suite 700
Denver, Colorado 80202-2126

Ladies and Gentlemen:

        We have acted as counsel for MarkWest Energy Partners, L.P., a Delaware limited partnership (the "Partnership") and certain of its subsidiaries with respect to the preparation of the Registration Statement on Form S-3 (the "Registration Statement") filed on the date hereof with the Securities and Exchange Commission (the "Commission") in connection with the registration by the Partnership under the Securities Act of 1933, as amended (the "Securities Act"), of the offer and sale by the Partnership from time to time, pursuant to Rule 415 under the Securities Act, of:

        (1)   common units representing limited liability company interests in the Partnership (the "Common Units");

        (2)   debt securities, which may be co-issued by MarkWest Energy Finance Corp., a Delaware corporation ("MarkWest Energy Finance"), in one or more series, consisting of notes, debentures or other evidences of indebtedness (the "Debt Securities"); and

        (3)   guarantees (the "Guarantees") of the Debt Securities by of certain subsidiaries of the Partnership listed in the Registration Statement as guarantors (the "Guarantors").

        The Common Units, Debt Securities and Guarantees are collectively referred to herein as the "Securities." We have also participated in the preparation of each of the Prospectus (the "Prospectus") contained in the Registration Statement to which this opinion is an exhibit. Capitalized terms not defined herein shall have the meanings ascribed to them in the Prospectus.

        We have examined the Registration Statement, including the Prospectus, the form of Senior Indenture (the "Senior Indenture") filed as an exhibit to the Registration Statement the form of Subordinated Indenture (the "Subordinated Indenture", together with the Senior Indenture, the "Indentures") filed as an exhibit to the Registration Statement, the Second Amended and Restated Agreement of Limited Partnership of the Partnership, as amended (the "Partnership Agreement "), the Certificate of Limited Partnership (the "Certificate") filed with the Secretary of State of Delaware pursuant to the Delaware Revised Uniform Limited Partnership Act in connection with the formation of the Partnership, other formation documents and agreements, as applicable, of MarkWest Energy Finance and the Subsidiary Guarantors and such other documents as we have deemed necessary or appropriate for purposes of this opinion. In addition, we have reviewed certain certificates of officers of the Partnership and of public officials, and we have relied on such certificates with respect to certain factual matters that we have not independently established.

        In connection with this opinion, we have assumed that:

          (i)  the Registration Statement, and any amendments thereto (including post-effective amendments), will have become effective;

         (ii)  a Prospectus Supplement will have been prepared and filed with the Commission describing the Securities offered thereby;

        (iii)  all Securities will be issued and sold in compliance with applicable federal and state securities laws and in the manner stated in the Registration Statement and the appropriate Prospectus Supplement;

        (iv)  a definitive purchase, underwriting or similar agreement with respect to any Securities offered will have been duly authorized and validly executed and delivered by the Partnership and the other parties thereto; and

         (v)  any Securities issuable upon conversion, exchange or exercise of any Security being offered will be duly authorized, created and, if appropriate, reserved for issuance upon such conversion, exchange or exercise.

        Based upon and subject to the foregoing, we are of the opinion that:

        (1)   With respect to the Common Units, when (i) the Partnership has taken all necessary action to approve the issuance of such Common Units, the terms of the offering thereof and related matters and (ii) the Common Units have been issued and delivered in accordance with the terms of the applicable definitive purchase, underwriting or similar agreement approved by the Partnership upon payment of the consideration thereof or provided for therein, then the Common Units will be validly issued, fully paid and non-assessable.

        (2)   With respect to the Debt Securities and the Guarantees, when (i) the Indentures have been duly qualified under the Trust Indenture Act of 1939, as amended; (ii) the Partnership, MarkWest Energy Finance and the Subsidiary Guarantors, as applicable, have taken all necessary action to approve the issuance and terms of such Debt Securities and Guarantees, the terms of the offering thereof and related matters; and (iii) such Debt Securities and Guarantees have been duly executed, authenticated, issued and delivered in accordance with the provisions of the applicable Indenture and the applicable definitive purchase, underwriting or similar agreement approved by the Partnership, MarkWest Energy Finance and the Subsidiary Guarantors, as applicable, upon payment of the consideration thereof or provided for therein, such Debt Securities and Guarantees will be legally issued and will constitute valid and legally binding obligations of the Partnership, MarkWest Energy Finance and the Subsidiary Guarantors, as applicable, enforceable against the Partnership, MarkWest Energy Finance and the Subsidiary Guarantors, as applicable, in accordance with their terms, except as such enforcement may be subject to any applicable bankruptcy, insolvency, reorganization, fraudulent conveyance or other law relating to or affecting creditors' rights generally and general principles of equity.

        The opinions expressed herein are qualified in the following respects:

        (1)   We have assumed, without independent verification, that the certificates for the Common Units will conform to the specimens thereof examined by us and will have been duly countersigned by a transfer agent and duly registered by a registrar of the Common Units.

        (2)   We have assumed that (i) each document submitted to us for review is accurate and complete, each such document that is an original is authentic, each such document that is a copy conforms to an authentic original and all signatures on each such document are genuine and (ii) each certificate from governmental officials reviewed by us is accurate, complete and authentic, and all official public records are accurate and complete.

        (3)   We express no opinions concerning (i) the validity or enforceability of any provisions contained in the Indentures that purport to waive or not give effect to the rights to notices, defenses, subrogation or other rights or benefits that cannot be effectively waived under applicable law; or (ii) the enforceability of indemnification provisions to the extent they purport to relate to liabilities resulting from or based upon negligence or any violation of federal or state securities or blue sky laws.

        (4)   This opinion is limited in all respects to federal laws, the Delaware Limited Liability Partnership Act and the Constitution of the State of Delaware, as interpreted by the courts of the State of Delaware and of the United States.

        We hereby consent to the references to this firm under the caption "Legal Matters" in the Prospectus and to the filing of this opinion as an Exhibit to the Registration Statement. By giving such consent, we do not admit that we are within the category of persons whose consent is required under

Section 7 of the Securities Act or the rules and regulations of the Securities and Exchange Commission issued thereunder.

Very truly yours,

/s/ Vinson & Elkins L.L.P.

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Exhibit 5.1

EX-8.1

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Exhibit 8.1

January 13, 2010

MarkWest Energy Partners, L.P.
1515 Arapahoe Street
Tower 2, Suite 700
Denver, Colorado 80202

        RE: MARKWEST ENERGY PARTNERS, L.P.; REGISTRATION STATEMENT ON FORM S-3

Ladies and Gentlemen:

        We have acted as counsel to MarkWest Energy Partners, L.P. (the "Partnership"), a Delaware limited partnership, and MarkWest Energy Finance Corp. (the "Finance Corp"), a Delaware corporation, with respect to certain legal matters in connection with the preparation of the Registration Statement on Form S-3 (the "Registration Statement") filed with the Securities and Exchange Commission (the "Commission") on the date hereof and to which this opinion is an exhibit. The Registration Statement relates to the registration under the Securities Act of 1933, as amended (the "Securities Act"), of the offer and sale, from time to time, pursuant to Rule 415 under the Securities Act, of:

        (1)   common units representing limited partner interests in the Partnership;

        (2)   debt securities of the Partnership and the Finance Corp. (the "Debt Securities"); and

        (3)   guarantees of the Debt Securities by certain Partnership subsidiaries.

In connection therewith, we prepared the discussion (the "Discussion") set forth under the caption "Material Tax Consequences" in the Registration Statement.

        All statements of legal conclusions contained in the Discussion, unless otherwise noted, are our opinion with respect to the matters set forth therein as of the date hereof, qualified by the limitations contained in the Discussion. In addition, we are of the opinion that the Discussion with respect to those matters as to which no legal conclusions are provided is an accurate discussion of such federal income tax matters (except for the representations and statements of fact by the Partnership and its general partner, included in the Discussion, as to which we express no opinion).

        We hereby consent to the filing of this opinion as an exhibit to the Registration Statement and to the use of our name under the heading "Legal" therein. This consent does not, however, constitute an admission that we are "experts" within the meaning of such term as used in the Securities Act, or the rules and regulations of the Commission issued thereunder.

Very truly yours,

/s/ VINSON & ELKINS L.L.P.

Vinson & Elkins L.L.P.

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Exhibit 8.1

EX-12.1

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Exhibit 12.1

MarkWest Energy Partners, L.P.
Calculation of Earnings to Fixed Charges

(Dollar amounts in thousands)

		Year ended December 31,															Nine Months Ended September 30,
		2004			2005			2006			2007			2008			2009
Fixed Charges			17,192			34,080			54,153			49,191			86,559			82,079
Earnings			22,942			28,221			122,690			(7,299	)		352,140			(42,595	)
Add:
	(a) Pre-tax income from continuing operations		6,490			(8,515	)		74,498			(59,155	)		273,602			(115,124	)
	(b) Fixed charges		17,192			34,080			54,153			49,191			86,559			82,079
	(c) Amortization of capitalized interest		53			195			255			478			1,110			972
	(d) Distributed income of equity investees		—			2,441			—			10,840			445			—
	(e) Share of pre-tax losses (earnings) of equity investees		—			2,153			(5,316	)		(5,309	)		(90	)		(1,260	)
Subtract
	(a) Interest capitalized		(793	)		(2,133	)		(900	)		(3,344	)		(9,486	)		(9,262	)
Equals Earnings			22,942			28,221			122,690			(7,299	)		352,140			(42,595	)
Ratio			1.33			0.83			2.27			(0.15	)		4.07			(0.52	)

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Exhibit 12.1

EX-21.1

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Exhibit 21.1

Subsidiaries of the Registrant

Entity	State of Incorporation
Bright Star Partnership	Texas
Centrahoma Processing LLC	Delaware
MarkWest Blackhawk, L.L.C.	Texas
MarkWest Energy Appalachia, L.L.C.	Delaware
MarkWest Energy East Texas Gas Company, L.L.C.	Delaware
MarkWest Energy Finance Corporation	Delaware
MarkWest Energy GP, L.L.C.	Delaware
MarkWest Energy Operating Company, L.L.C.	Delaware
MarkWest Gas Marketing, L.L.C.	Texas
MarkWest Gas Services, L.L.C.	Texas
MarkWest Hydrocarbon, Inc.	Delaware
MarkWest Javelina Company, L.L.C.	Texas
MarkWest Javelina Pipeline Company, L.L.C.	Texas
MarkWest Liberty Gas Gathering, L.L.C.	Delaware
MarkWest Liberty Midstream & Resources, L.L.C.	Delaware
MarkWest Marketing, L.L.C.	Delaware
MarkWest McAlester, L.L.C.	Oklahoma
MarkWest Michigan Pipeline Company, L.L.C.	Michigan
MarkWest New Mexico, L.L.C.	Texas
MarkWest Pinnacle, L.L.C.	Texas
MarkWest Pioneer, L.L.C.	Delaware
MarkWest Pipeline Company, L.L.C.	Texas
MarkWest PNG Utility, L.L.C.	Texas
MarkWest Power Tex, L.L.C.	Texas
MarkWest Texas PNG Utility, L.L.C.	Texas
MarkWest Oklahoma Gas Company, L.L.C.	Oklahoma
Mason Pipeline Limited Liability Company	Michigan
Matrex, L.L.C.	Michigan
West Shore Processing Company, L.L.C.	Michigan
Wirth Gathering, a General Partnership	Oklahoma

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Exhibit 21.1

EX-23.1

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Exhibit 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

        We consent to the incorporation by reference in this Registration Statement on Form S-3 of our report dated March 2, 2009 (May 18, 2009 as to the effects of the retrospective applications of changes to generally accepted accounting principles related to the presentation of non-controlling interest and the calculation of earnings per share and the related disclosures in Notes 1, 2 and 21, which report expressed an unqualified opinion and included an explanatory paragraph concerning the retrospective adjustments), relating to the consolidated financial statements of MarkWest Energy Partners, L.P. and subsidiaries (which report expressed an unqualified opinion and included an explanatory paragraph concerning the retrospective adjustments), appearing in the current report on Form 8-K of MarkWest Energy Partners, L.P. dated May 18, 2009, and our report dated March 2, 2009 relating to the effectiveness of MarkWest Energy Partners L.P. and subsidiaries' internal control over financial reporting, appearing in the Annual Report on Form 10-K of MarkWest Energy Partners, L.P. for the year ended December 31, 2008, and to the reference to us under the heading "Experts" in the Prospectus, which is part of this Registration Statement.

/s/ DELOITTE & TOUCHE LLP

Denver, Colorado
January 13, 2010

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CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

EX-23.2

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EXHIBIT 23.2

CONSENT OF INDEPENDENT ACCOUNTANTS

        We hereby consent to the incorporation by reference in this Registration Statement on Form S-3 of MarkWest Energy Partners, L.P. and MarkWest Energy Finance Corp. of our report dated February 22, 2008 relating to the financial statements of Starfish Pipeline Company, LLC, which appears in MarkWest Energy Partners, L.P.'s Annual Report on Form 10-K for the year ended December 31, 2008. We also consent to the reference to us under the heading "Experts" in such Registration Statement.

/s/ PricewaterhouseCoopers LLP

Houston, Texas
January 11, 2010

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EXHIBIT 23.2

CONSENT OF INDEPENDENT ACCOUNTANTS

EX-25.1

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Exhibit 25.1

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM T-1

STATEMENT OF ELIGIBILITY
UNDER THE TRUST INDENTURE ACT OF 1939 OF A
CORPORATION DESIGNATED TO ACT AS TRUSTEE

o CHECK IF AN APPLICATION TO DETERMINE ELIGIBILITY OF A TRUSTEE PURSUANT TO SECTION 305(b) (2)

WELLS FARGO BANK, NATIONAL ASSOCIATION
(Exact name of trustee as specified in its charter)

A National Banking Association	94-1347393
(Jurisdiction of incorporation or	(I.R.S. Employer
organization if not a U.S. national	Identification No.)
bank)
101 North Phillips Avenue Sioux Falls, South Dakota (Address of principal executive offices)	57104 (Zip code)

Wells Fargo & Company
Law Department, Trust Section
MAC N9305-175
Sixth Street and Marquette Avenue, 17^th Floor
Minneapolis, Minnesota 55479
(612) 667-4608
(Name, address and telephone number of agent for service)

MARKWEST ENERGY PARTNERS, L.P.
MARKWEST ENERGY FINANCE CORPORATION
(Exact name of obligor as specified in its charter)

Delaware Delaware	27-0005456 20-1805917
(State or other jurisdiction of incorporation or organization)	(I.R.S. Employer Identification No.)

1515 Arapahoe Street
Tower 2, Suite 700
Denver, Colorado 80202
(303) 925-9200
(Address, Including Zip Code, and Telephone Number, Including Area
Code, of Registrant's Principal Executive Offices)

SENIOR NOTES SHELF REGISTRATION

Item 1.    General Information. Furnish the following information as to the trustee:

(a)

Name and address of each examining or supervising authority to which it is subject.

Comptroller of the Currency
Treasury Department
Washington, D.C.

Federal Deposit Insurance Corporation
Washington, D.C.

Federal Reserve Bank of San Francisco
San Francisco, California 94120

(b)

Whether it is authorized to exercise corporate trust powers.

The trustee is authorized to exercise corporate trust powers.

Item 2.    Affiliations with Obligor. If the obligor is an affiliate of the trustee, describe each such affiliation.

         None with respect to the trustee.

No responses are included for Items 3-14 of this Form T-1 because the obligor is not in default as provided under Item 13.

Item 15.    Foreign Trustee. Not applicable.

Item 16.    List of Exhibits. List below all exhibits filed as a part of this Statement of Eligibility.

Exhibit 1.	A copy of the Articles of Association of the trustee now in effect.*
Exhibit 2.	A copy of the Comptroller of the Currency Certificate of Corporate Existence and Fiduciary Powers for Wells Fargo Bank, National Association, dated February 4, 2004.**
Exhibit 3.	See Exhibit 2
Exhibit 4.	Copy of By-laws of the trustee as now in effect.***
Exhibit 5.	Not applicable.
Exhibit 6.	The consent of the trustee required by Section 321(b) of the Act.
Exhibit 7.	A copy of the latest report of condition of the trustee published pursuant to law or the requirements of its supervising or examining authority.
Exhibit 8.	Not applicable.
Exhibit 9.	Not applicable.

*

Incorporated by reference to the exhibit of the same number to the trustee's Form T-1 filed as exhibit 25 to the Form S-4 dated December 30, 2005 of Hornbeck Offshore Services LLC file number 333-130784-06.

**

Incorporated by reference to the exhibit of the same number to the trustee's Form T-1 filed as exhibit 25 to the Form T-3 dated March 3, 2004 of Trans-Lux Corporation file number 022-28721.

***

Incorporated by reference to the exhibit of the same number to the trustee's Form T-1 filed as exhibit 25 to the Form S-4 dated May 26, 2005 of Penn National Gaming Inc. file number 333-125274.

SIGNATURE

         Pursuant to the requirements of the Trust Indenture Act of 1939, as amended, the Trustee, Wells Fargo Bank, National Association, a national banking association organized and existing under the laws of the United States of America, has duly caused this statement of eligibility to be signed on its behalf by the undersigned, thereunto duly authorized, all in the City of Dallas and State of Texas on the 12th day of January, 2010.

WELLS FARGO BANK, NATIONAL ASSOCIATION

/s/ PATRICK T. GIORDANO   Patrick T. Giordano
Vice President

EXHIBIT 6

January 12, 2010

Securities and Exchange Commission
Washington, D.C. 20549

Gentlemen:

In accordance with Section 321(b) of the Trust Indenture Act of 1939, as amended, the undersigned hereby consents that reports of examination of the undersigned made by Federal, State, Territorial, or District authorities authorized to make such examination may be furnished by such authorities to the Securities and Exchange Commission upon its request thereof.

Very truly yours,

WELLS FARGO BANK, NATIONAL ASSOCIATION

/s/ PATRICK T. GIORDANO
Patrick T. Giordano
Vice President

Consolidated Report of Condition of
Wells Fargo Bank National Association
of 101 North Phillips Avenue, Sioux Falls, SD 57104
And Foreign and Domestic Subsidiaries,
at the close of business September 30, 2009, filed in accordance with 12 U.S.C. §161 for National Banks.

				Dollar Amounts In Millions
ASSETS
Cash and balances due from depository institutions:
	Noninterest-bearing balances and currency and coin			$	10,576
	Interest-bearing balances				3,224
Securities:
	Held-to-maturity securities				0
	Available-for-sale securities				83,255
Federal funds sold and securities purchased under agreements to resell:
	Federal funds sold in domestic offices				31,571
	Securities purchased under agreements to resell				1,574
Loans and lease financing receivables:
	Loans and leases held for sale				24,141
	Loans and leases, net of unearned income		336,946
	LESS: Allowance for loan and lease losses		10,037
	Loans and leases, net of unearned income and allowance				326,909
Trading Assets					9,540
Premises and fixed assets (including capitalized leases)					4,211
Other real estate owned					1,413
Investments in unconsolidated subsidiaries and associated companies					437
Direct and indirect investments in real estate ventures					50
Intangible assets
	Goodwill				11,407
	Other intangible assets				15,136
Other assets					24,246
Total assets				$	547,690
LIABILITIES
Deposits:
	In domestic offices			$	381,571
		Noninterest-bearing	79,823
		Interest-bearing	301,748
	In foreign offices, Edge and Agreement subsidiaries, and IBFs				57,166
		Noninterest-bearing	1,361
		Interest-bearing	55,805
Federal funds purchased and securities sold under agreements to repurchase:
	Federal funds purchased in domestic offices				3,708
	Securities sold under agreements to repurchase				4,401

	Dollar Amounts In Millions
Trading liabilities		8,869
Other borrowed money (includes mortgage indebtedness and obligations under capitalized leases)		7,405
Subordinated notes and debentures		12,392
Other liabilities		21,101
Total liabilities	$	496,613
EQUITY CAPITAL
Perpetual preferred stock and related surplus		0
Common stock		520
Surplus (exclude all surplus related to preferred stock)		30,685
Retained earnings		18,971
Accumulated other comprehensive income		725
Other equity capital components		0
Total bank equity capital		50,901
Noncontrolling (minority) interests in consolidated subsidiaries		176
Total equity capital		51,077
Total liabilities, and equity capital	$	547,690

I, Howard I. Atkins, EVP & CFO of the above-named bank do hereby declare that this Report of Condition has been prepared in conformance with the instructions issued by the appropriate Federal regulatory authority and is true to the best of my knowledge and belief.

Howard I. Atkins
EVP & CFO

We, the undersigned directors, attest to the correctness of this Report of Condition and declare that it has been examined by us and to the best of our knowledge and belief has been prepared in conformance with the instructions issued by the appropriate Federal regulatory authority and is true and correct.

John Stumpf
Carrie Tolstedt
Michael Loughlin Directors

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Exhibit 25.1
Item 1. General Information. Furnish the following information as to the trustee
Item 2. Affiliations with Obligor. If the obligor is an affiliate of the trustee, describe each such affiliation.
Item 15. Foreign Trustee. Not applicable.
Item 16. List of Exhibits. List below all exhibits filed as a part of this Statement of Eligibility.

EX-25.2

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Exhibit 25.2

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM T-1

STATEMENT OF ELIGIBILITY
UNDER THE TRUST INDENTURE ACT OF 1939 OF A
CORPORATION DESIGNATED TO ACT AS TRUSTEE

o CHECK IF AN APPLICATION TO DETERMINE ELIGIBILITY OF A TRUSTEE PURSUANT TO SECTION 305(b) (2)

WELLS FARGO BANK, NATIONAL ASSOCIATION
(Exact name of trustee as specified in its charter)

A National Banking Association	94-1347393
(Jurisdiction of incorporation or	(I.R.S. Employer
organization if not a U.S. national	Identification No.)
bank)
101 North Phillips Avenue Sioux Falls, South Dakota (Address of principal executive offices)	57104 (Zip code)

Wells Fargo & Company
Law Department, Trust Section
MAC N9305-175
Sixth Street and Marquette Avenue, 17^th Floor
Minneapolis, Minnesota 55479
(612) 667-4608
(Name, address and telephone number of agent for service)

MARKWEST ENERGY PARTNERS, L.P.
MARKWEST ENERGY FINANCE CORPORATION
(Exact name of obligor as specified in its charter)

Delaware Delaware	27-0005456 20-1805917
(State or other jurisdiction of incorporation or organization)	(I.R.S. Employer Identification No.)

1515 Arapahoe Street
Tower 2, Suite 700
Denver, Colorado 80202
(303) 925-9200
(Address, Including Zip Code, and Telephone Number, Including Area
Code, of Registrant's Principal Executive Offices)

SUBORDINATED NOTES SHELF REGISTRATION

Item 1.    General Information. Furnish the following information as to the trustee:

(a)

Name and address of each examining or supervising authority to which it is subject.

Comptroller of the Currency
Treasury Department
Washington, D.C.

Federal Deposit Insurance Corporation
Washington, D.C.


Federal Reserve Bank of San Francisco
San Francisco, California 94120

(b)

Whether it is authorized to exercise corporate trust powers.

The trustee is authorized to exercise corporate trust powers.

Item 2.    Affiliations with Obligor. If the obligor is an affiliate of the trustee, describe each such affiliation.

         None with respect to the trustee.

No responses are included for Items 3-14 of this Form T-1 because the obligor is not in default as provided under Item 13.

Item 15.    Foreign Trustee. Not applicable.

Item 16.    List of Exhibits. List below all exhibits filed as a part of this Statement of Eligibility.

Exhibit 1.	A copy of the Articles of Association of the trustee now in effect.*
Exhibit 2.	A copy of the Comptroller of the Currency Certificate of Corporate Existence and Fiduciary Powers for Wells Fargo Bank, National Association, dated February 4, 2004.**
Exhibit 3.	See Exhibit 2
Exhibit 4.	Copy of By-laws of the trustee as now in effect.***
Exhibit 5.	Not applicable.
Exhibit 6.	The consent of the trustee required by Section 321(b) of the Act.
Exhibit 7.	A copy of the latest report of condition of the trustee published pursuant to law or the requirements of its supervising or examining authority.
Exhibit 8.	Not applicable.
Exhibit 9.	Not applicable.

*

Incorporated by reference to the exhibit of the same number to the trustee's Form T-1 filed as exhibit 25 to the Form S-4 dated December 30, 2005 of Hornbeck Offshore Services LLC file number 333-130784-06.

**

Incorporated by reference to the exhibit of the same number to the trustee's Form T-1 filed as exhibit 25 to the Form T-3 dated March 3, 2004 of Trans-Lux Corporation file number 022-28721.

***

Incorporated by reference to the exhibit of the same number to the trustee's Form T-1 filed as exhibit 25 to the Form S-4 dated May 26, 2005 of Penn National Gaming Inc. file number 333-125274.

SIGNATURE

         Pursuant to the requirements of the Trust Indenture Act of 1939, as amended, the Trustee, Wells Fargo Bank, National Association, a national banking association organized and existing under the laws of the United States of America, has duly caused this statement of eligibility to be signed on its behalf by the undersigned, thereunto duly authorized, all in the City of Dallas and State of Texas on the 12th day of January, 2010.

WELLS FARGO BANK, NATIONAL ASSOCIATION

/s/ PATRICK T. GIORDANO   Patrick T. Giordano
Vice President

EXHIBIT 6

January 12, 2010

Securities and Exchange Commission
Washington, D.C. 20549

Gentlemen:

In accordance with Section 321(b) of the Trust Indenture Act of 1939, as amended, the undersigned hereby consents that reports of examination of the undersigned made by Federal, State, Territorial, or District authorities authorized to make such examination may be furnished by such authorities to the Securities and Exchange Commission upon its request thereof.

Very truly yours,

WELLS FARGO BANK, NATIONAL ASSOCIATION

/s/ PATRICK T. GIORDANO
Patrick T. Giordano
Vice President

Consolidated Report of Condition of
Wells Fargo Bank National Association
of 101 North Phillips Avenue, Sioux Falls, SD 57104
And Foreign and Domestic Subsidiaries,

at the close of business September 30, 2009, filed in accordance with 12 U.S.C. §161 for National Banks.

				Dollar Amounts In Millions
ASSETS
Cash and balances due from depository institutions:
	Noninterest-bearing balances and currency and coin			$	10,576
	Interest-bearing balances				3,224
Securities:
	Held-to-maturity securities				0
	Available-for-sale securities				83,255
Federal funds sold and securities purchased under agreements to resell:
	Federal funds sold in domestic offices				31,571
	Securities purchased under agreements to resell				1,574
Loans and lease financing receivables:
	Loans and leases held for sale				24,141
	Loans and leases, net of unearned income		336,946
	LESS: Allowance for loan and lease losses		10,037
	Loans and leases, net of unearned income and allowance				326,909
Trading Assets					9,540
Premises and fixed assets (including capitalized leases)					4,211
Other real estate owned					1,413
Investments in unconsolidated subsidiaries and associated companies					437
Direct and indirect investments in real estate ventures					50
Intangible assets
	Goodwill				11,407
	Other intangible assets				15,136
Other assets					24,246
Total assets				$	547,690
LIABILITIES
Deposits:
	In domestic offices			$	381,571
		Noninterest-bearing	79,823
		Interest-bearing	301,748
	In foreign offices, Edge and Agreement subsidiaries, and IBFs				57,166
		Noninterest-bearing	1,361
		Interest-bearing	55,805
Federal funds purchased and securities sold under agreements to repurchase:
	Federal funds purchased in domestic offices				3,708
	Securities sold under agreements to repurchase				4,401

	Dollar Amounts In Millions
Trading liabilities		8,869
Other borrowed money (includes mortgage indebtedness and obligations under capitalized leases)		7,405
Subordinated notes and debentures		12,392
Other liabilities		21,101
Total liabilities	$	496,613
EQUITY CAPITAL
Perpetual preferred stock and related surplus		0
Common stock		520
Surplus (exclude all surplus related to preferred stock)		30,685
Retained earnings		18,971
Accumulated other comprehensive income		725
Other equity capital components		0
Total bank equity capital		50,901
Noncontrolling (minority) interests in consolidated subsidiaries		176
Total equity capital		51,077
Total liabilities, and equity capital	$	547,690

I, Howard I. Atkins, EVP & CFO of the above-named bank do hereby declare that this Report of Condition has been prepared in conformance with the instructions issued by the appropriate Federal regulatory authority and is true to the best of my knowledge and belief.

Howard I. Atkins
EVP & CFO

We, the undersigned directors, attest to the correctness of this Report of Condition and declare that it has been examined by us and to the best of our knowledge and belief has been prepared in conformance with the instructions issued by the appropriate Federal regulatory authority and is true and correct.

John Stumpf
Carrie Tolstedt
Michael Loughlin Directors

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Exhibit 25.2
Item 1. General Information. Furnish the following information as to the trustee
Item 2. Affiliations with Obligor. If the obligor is an affiliate of the trustee, describe each such affiliation.
Item 15. Foreign Trustee. Not applicable.
Item 16. List of Exhibits. List below all exhibits filed as a part of this Statement of Eligibility.