8-K/A

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K/A

(Amendment No. 1)

CURRENT REPORT

Pursuant to Section 13 or 15(d)

of the Securities Exchange Act of 1934

January 2, 2014 (November 12, 2013)

Date of Report (Date of earliest event reported)

CRESTWOOD MIDSTREAM PARTNERS LP

(Exact name of Registrant as specified in its charter)

Delaware	001-35377	20-1647837
(State or other jurisdiction of incorporation)	(Commission File Number)	(IRS Employer Identification Number)

700 Louisiana Street, Suite 2060

Houston, Texas 77002

(Address of principal executive offices)

(832) 519-2200

(Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

¨ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

¨ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

¨ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

¨ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Explanatory Note

On November 12, 2013, Crestwood Midstream Partners LP (the “Partnership”) filed a Current Report on Form 8-K (the “Original Report”) announcing the consummation of the Partnership’s previously announced acquisition of Arrow Midstream Holdings, LLC (“Arrow”), pursuant to an Agreement and Plan of Merger, dated as of October 8, 2013, among the Partnership, Crestwood Arrow Acquisition LLC, Arrow, and Arrow’s members, Legion Energy, LLC and OZ Midstream Holdings, LLC (the “Arrow Acquisition”).

On October 17, 2013, the Partnership filed a Current Report on Form 8-K which included (i) the audited consolidated financial statements of Arrow and related footnotes as of December 31, 2012 and 2011 and for each of the two years in the period ended December 31, 2012, (ii) the unaudited condensed consolidated financial statements of Arrow and related footnotes as of June 30, 2013 and for the six months ended June 30, 2013 and 2012 and (iii) the unaudited pro forma condensed combined financial statements of the Partnership as of June 30, 2013, giving effect to the Arrow Acquisition (together, the “Previously Filed Financial Statements”).

This Amendment No. 1 on Form 8-K/A amends the Original Report to (i) update the Previously Filed Financial Statements and (ii) include such financial statements on the Original Report as required by Item 9.01 of Form 8-K.

Item 9.01 Financial Statements and Exhibits.

(a) Financial Information of Businesses Acquired.

The audited consolidated financial statements of Arrow as of December 31, 2012 and 2011 and for each of the two years in the period ended December 31, 2012, and the related notes thereto, together with the report of Grant Thornton LLP, independent certified public accountants, concerning those statements and related notes, are attached as Exhibit 99.1 to the Current Report on Form 8-K filed by the Partnership on October 17, 2013 and are incorporated herein by reference.

The unaudited condensed consolidated financial statements of Arrow as of June 30, 2013 and for the three and six months ended June 30, 2013 and 2012, and the related notes thereto, are attached as Exhibit 99.2 to the Current Report on Form 8-K filed by the Partnership on October 17, 2013 and are incorporated herein by reference.

The unaudited condensed consolidated interim financial statements of Arrow as of September 30, 2013 and for the nine months ended September 30, 2013 and 2012, and the related notes thereto are attached hereto as Exhibit 99.3 and incorporated herein by reference.

(b) Pro Forma Financial Information.

Unaudited pro forma condensed combined consolidated financial information of the Partnership is attached hereto as Exhibit 99.4 and incorporated herein by reference:

• Introduction

• Unaudited pro forma condensed combined consolidated balance sheet as of September 30, 2013

• Unaudited pro forma condensed combined consolidated statements of operations for the year ended December 31, 2012

• Unaudited pro forma condensed combined consolidated statements of operations for the nine months ended September 30, 2013

• Notes to unaudited pro forma condensed combined consolidated financial statements

The unaudited pro forma condensed combined consolidated financial information of the Partnership included in this filing amends and supersedes in its entirety the unaudited pro forma condensed combined consolidated financial information included as Exhibit 99.3 to the Current Report on Form 8-K filed by the Partnership on October 17, 2013.

(d) Exhibits

Exhibit     No.	Description
99.1	Arrow Midstream Holdings, LLC’s audited consolidated financial statements and related footnotes as of December 31, 2012 and 2011 and for each of the two years in the period ended December 31, 2012 (incorporated herein by reference to Exhibit 99.1 to Crestwood Midstream Partners LP’s Form 8-K filed on October 17, 2013)
99.2	Arrow Midstream Holdings, LLC’s unaudited condensed consolidated financial statements and related footnotes as of June 30, 2013 and for the six months ended June 30, 2013 and 2012 (incorporated herein by reference to Exhibit 99.2 to Crestwood Midstream Partners LP’s Form 8-K filed on October 17, 2013)
99.3	Arrow Midstream Holdings, LLC’s unaudited condensed consolidated interim financial statements and related footnotes as of September 30, 2013 and for the nine months ended September 30, 2013 and 2012.
99.4	Unaudited pro forma condensed combined consolidated financial statements of the Partnership, giving effect to the Arrow Acquisition.

2

Signatures

Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

	CRESTWOOD MIDSTREAM PARTNERS LP
	By:	Crestwood Midstream GP, LLC,
		its General Partner
Date: January 2, 2014	By:	/s/ Michael J. Campbell
		Michael J. Campbell
		Senior Vice President and Chief Financial Officer

3

Exhibit Index

Exhibit     No.	Description
99.1	Arrow Midstream Holdings, LLC’s audited consolidated financial statements and related footnotes as of December 31, 2012 and 2011 and for each of the two years in the period ended December 31, 2012 (incorporated herein by reference to Exhibit 99.1 to Crestwood Midstream Partners LP’s Form 8-K filed on October 17, 2013)
99.2	Arrow Midstream Holdings, LLC’s unaudited condensed consolidated financial statements and related footnotes as of June 30, 2013 and for the six months ended June 30, 2013 and 2012 (incorporated herein by reference to Exhibit 99.2 to Crestwood Midstream Partners LP’s Form 8-K filed on October 17, 2013)
99.3	Arrow Midstream Holdings, LLC’s unaudited condensed consolidated interim financial statements and related footnotes as of September 30, 2013 and for the nine months ended September 30, 2013 and 2012.
99.4	Unaudited pro forma condensed combined consolidated financial statements of the Partnership, giving effect to the Arrow Acquisition.

4

EX-99.3

Exhibit 99.3

Arrow Midstream Holdings, LLC and Subsidiaries

Condensed Consolidated Balance Sheets

September 30, 2013 and December 31, 2012

(Unaudited)

(In thousands)

	September 30, 2013			December 31, 2012
ASSETS
CURRENT ASSETS:
Cash	$	14,628		$	31,158
Accounts receivable		148,786			93,951
Accounts receivable - related party		—			21
Other receivables		86			2,059
Inventory		1,024			1,197
Debt issuance costs		923			—
Total current assets		165,447			128,386
PROPERTY AND EQUIPMENT, at cost		244,234			145,404
Less - accumulated depreciation		(14,460	)		(9,851	)
Property and equipment, net		229,774			135,553
NONCURRENT ASSETS:
Other assets		17,860			13,679
Total assets	$	413,081		$	277,618
LIABILITIES AND MEMBERS’ EQUITY
CURRENT LIABILITIES:
Accounts payable - trade	$	33,748		$	22,337
Producers payable		126,945			101,600
Advances payable		5,735			813
Current portion of debt and capital lease		51,235			1,961
Total current liabilities		217,663			126,711
NONCURRENT LIABILITIES:
Debt and capital lease, less current maturities		—			15,739
Other long-term liabilities		3,733			3,733
Total noncurrent liabilities		3,733			19,472
MEMBERS’ EQUITY		191,685			131,435
Total liabilities and members’ equity	$	413,081		$	277,618

The accompanying notes are an integral part of these condensed consolidated financial statements.

Arrow Midstream Holdings, LLC and Subsidiaries

Condensed Consolidated Statements of Operations

For the nine months ended September 30, 2013 and 2012

(Unaudited)

(In thousands)

	Nine Months Ended September 30,
	2013			2012
REVENUES:
Product sales	$	1,079,003		$	465,081
Oil pipeline fee and gas transportation fee		26,392			13,639
Water disposal		3,513			1,519
TOTAL REVENUES		1,108,908			480,239
COSTS AND EXPENSES:
Cost of revenues		(1,068,094	)		(461,025	)
Operating		(14,117	)		(7,884	)
General and administrative		(3,318	)		(2,216	)
Depreciation		(4,627	)		(3,606	)
Interest		(727	)		(15	)
Other		232			(9	)
NET INCOME		18,257			5,484
Less: Net income attributable to noncontrolling interest		1,243			525
NET INCOME ATTRIBUTABLE TO ARROW MIDSTREAM HOLDINGS, LLC	$	17,014		$	4,959

The accompanying notes are an integral part of these condensed consolidated financial statements.

Arrow Midstream Holdings, LLC and Subsidiaries

Condensed Consolidated Statements of Members’ Equity

(Unaudited)

(In thousands)

	Class A Interest		Class B Interest		Management Fee Interest		Noncontrolling Interest		Total
Ending balance, December 31, 2012	$	112,775	$	5,936	$	177	$	12,547	$	131,435
Contributions		35,002		1,842		—		5,149		41,993
Net income		16,163		851		—		1,243		18,257
Ending balance, September 30, 2013	$	163,940	$	8,629	$	177	$	18,939	$	191,685

The accompanying notes are an integral part of these condensed consolidated financial statements.

Arrow Midstream Holdings, LLC and Subsidiaries

Condensed Consolidated Statements of Cash Flows

For the nine months ended September 30, 2013 and 2012

(Unaudited)

(In thousands)

	Nine Months Ended September 30,
	2013			2012
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$	18,257		$	5,484
Adjustments to reconcile net income to net cash (used in) provided by operating activities:
Depreciation expense		4,627			3,606
Amortization of debt issuance costs		39			—
Change in operating assets and liabilities:
Accounts receivable		(49,366	)		(32,265	)
Accounts receivable - related party		21			56
Other receivables		1,973			399
Inventory		173			247
Accounts payable - trade		(9,331	)		2,733
Accounts payable - related party		—			(230	)
Producers payable		25,344			28,736
Net cash (used in) provided by operating activities		(8,263	)		8,766
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchase of property and equipment		(78,107	)		(13,267	)
Change in advances payable		4,922			6,229
Prepayment of property and equipment		(4,182	)		(18,543	)
Change in contributions in aid of construction		(5,469	)		(10,122	)
Net cash used in investing activities		(82,836	)		(35,703	)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from debt and capital lease		35,000			—
Payments of debt and capital lease		(1,462	)		—
Debt issuance costs		(962	)		—
Members’ contributions		36,844			20,834
Noncontrolling interest contributions		5,149			2,361
Net cash provided by financing activities		74,569			23,195
NET DECREASE IN CASH		(16,530	)		(3,742	)
CASH, beginning of period		31,158			11,137
CASH, end of period	$	14,628		$	7,395
NONCASH INVESTING AND OPERATING ACTIVITIES:
Property and equipment purchases payable	$	20,742		$	4,305
Outstanding members’ contribution	$	—		$	—
Producer contributed line fill	$	—		$	779
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION:
Cash paid for interest expense	$	672		$	9

The accompanying notes are an integral part of these condensed consolidated financial statements.

Arrow Midstream Holdings, LLC and Subsidiaries

Notes to unaudited condensed consolidated financial statements

(In thousands)

A - BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

1. General

Arrow Midstream Holdings, LLC (“the Company”), a Delaware limited liability company, was formed on October 3, 2008 to own, develop, maintain, manage and operate the business of its subsidiaries (collectively the “Arrow System”) in Dunn and McKenzie County, North Dakota. The Company conducts its business through its subsidiaries:

• Arrow Pipeline, LLC (“APL”), an 87% majority-owned Delaware limited liability company, which owns and operates approximately 150 miles of crude oil, natural gas and water transportation pipelines on the Fort Berthold Indian Reservation. As of July 31, 2013, APL was 88% owned by AMH and 10% by MHA. A two percent interest had been reserved for Bow Midstream Holdings, LLC (“Bow”), an original partner in the development. After MHA purchased its 10% interest in APL in April 2013, Bow had until July 31, 2013 to repay the support payment associated with its 2% interest. Bow elected not to repay the support and as a result relinquished its ownership interest in APL as of July 31, 2013. On August 30, 2013, MHA elected to purchase an additional 3% interest in APL for total consideration of $6,801, bringing its total ownership in APL to 13%.

• Arrow Field Services, LLC (“AFS”), a wholly-owned Delaware limited liability company, which owns and operates the storage and central delivery facilities for oil, gas and water that is transported on the Arrow System; and

• Arrow Water, LLC (“AW”), a wholly-owned Delaware limited liability company, which operates a salt water disposal facility.

The Company’s principal operations, transporting crude oil, natural gas and water and disposing water, commenced during the first quarter of 2010.

2. Consolidation and Presentation

The accompanying condensed consolidated financial statements include the accounts of the Company and its subsidiaries, APL, AFS and AW. All intercompany accounts and transactions have been eliminated in consolidation. The Company has recorded a noncontrolling interest in its subsidiary, APL, for the portion (13%) of the subsidiary that the Company does not own. The noncontrolling interest has been accounted for as equity in the unaudited condensed consolidated balance sheet.

The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (“U.S. GAAP”) for interim financial statements. These financial statements have not been audited by the Company’s independent certified public accountants, except that the unaudited condensed consolidated balance sheet at December 31, 2012 is derived from audited consolidated financial statements. Accordingly, they do not include all of the information and notes required by U.S. GAAP for complete financial statements. The financial statements reflect all adjustments (all of which are of a normal recurring nature) which are, in the opinion of management, necessary for a fair statement of the results for the interim periods presented. Interim results are not necessarily indicative of the results that may be expected for a full year. Certain disclosures have been condensed in or omitted from these unaudited condensed consolidated financial statements. The accompanying unaudited condensed consolidated financial statements should be read in conjunction with the consolidated financial statements and notes thereto for the year ended December 31, 2012.

Arrow Midstream Holdings, LLC and Subsidiaries

Notes to unaudited condensed consolidated financial statements - continued

(In thousands)

B - PROPERTY AND EQUIPMENT

Property and equipment, and estimated lives, consist of the following:

	September 30,			December 31,
	2013			2012
Property and equipment, at cost
Transportation pipeline (20 years)	$	101,890		$	77,677
Central delivery facility (20 years)		26,194			24,006
Water disposal facility (20 years)		8,943			3,205
Building (30 years)		160			160
Vehicles, furniture and equipment (3 - 5 years)		3,589			2,680
Construction-in-progress		99,164			33,757
Line fill		4,294			3,919
		244,234			145,404
Less: Accumulated depreciation		(14,460	)		(9,851	)
Property and equipment, net	$	229,774		$	135,553

At September 30, 2013, construction-in-progress consisted of costs associated with additional pipeline expansion projects as well as project costs for a connection to a third-party pipeline and various site improvement projects. These projects are expected to be completed throughout 2013. No depreciation expense was recorded for the nine months ended September 30, 2013 and 2012 for costs included in construction-in-progress.

Line fill is the minimum amount of oil required for the pipeline to be operational. The Company purchases line fill, as required, from producers. Also, producers are required to contribute certain volumes of line fill upon connection to the pipeline. Line fill is not depreciated. As of September 30, 2013, the Company owned $561 of line fill and producer contributed line fill totaled $3,733. As of December 31, 2012, the Company owned $187 of line fill and producer contributed line fill totaled $3,733. The Company has recorded a corresponding payable of $3,733 for the producer contributed line fill, which is included in long-term liabilities on the unaudited condensed consolidated balance sheets, as of September 30, 2013 and December 31, 2012. Line fill is valued at lower of cost or market.

C - DEBT AND CAPITAL LEASE

In June 2013, the Company entered into a five year $32,300 credit agreement (“Credit Agreement”). Loans under the Credit Agreement will bear interest at LIBOR plus a 1.25% to 2.25% margin depending on leverage ratios. Pursuant to the Credit Agreement, the Company may request up to an additional $150,000 in commitments, for a maximum aggregate commitment of $182,300. On August 7, 2013 the Company entered into a Commitment Increase Agreement under the terms of the existing Credit Agreement whereby the aggregate commitment was increased from $150,000 to $182,300. In conjunction with the amendment, US Bank syndicated the existing loan to six additional lenders. Commitment fees are payable quarterly at rates between 0.375% and 0.500% per year. Subject to certain conditions stated in the Credit Agreement, the Company may borrow, prepay and re-borrow amounts under the revolving credit facility at any time during the term of the Credit Agreement. The Credit Agreement contains customary representations, warranties, affirmative and negative covenants, including financial covenants, events of default and indemnification

Arrow Midstream Holdings, LLC and Subsidiaries

Notes to unaudited condensed consolidated financial statements - continued

(In thousands)

provisions in favor of the lenders. As of September 30, 2013, $35,000 was outstanding under the Credit Agreement, and the Company was in compliance with all of the covenants. As of September 30, 2013, the Company incurred $962 in debt issuance costs related to the Credit Agreement, which are capitalized and amortized over the term of the Credit Agreement. For the nine months ended September 30, 2013, amortization of debt issuance costs was $39.

On July 3, 2012, APL entered into a master lease agreement with a financial institution to purchase certain equipment. The lease agreement has a term of eight years and bears interest at 3.4%. At December 31, 2012, $17,700 was funded under this agreement. As of September 30, 2013, $16,235 was outstanding under the capital lease financing. The Company is the guarantor of the lease agreement. The lease agreement contains certain financial and other covenants. As of September 30, 2013, the Company is in compliance with all covenants.

On November 8, 2013, the Company was acquired by Crestwood Arrow Acquisition LLC (“Crestwood Arrow”). Both the Credit Agreement and the capital lease agreement terminated in connection with the Crestwood Arrow acquisition. Crestwood Arrow paid off the $55,000 balance outstanding under the Credit Agreement, and the Company expensed the unamortized portion of the debt issuance costs of $1,251 at the November 8, 2013 closing date. Additionally, the Company paid the balance outstanding of $16,070 under the capital lease and incurred $2,036 in termination fees at the November 8, 2013 closing date. See Note I for further discussion of the Crestwood Arrow acquisition.

D - COMMITMENTS AND CONTINGENCIES

Litigation

The Company is a party to proceedings and claims incidental to its business. While many of these matters involve inherent uncertainty, the Company believes that the amount of the liability, if any, ultimately incurred with respect to any such proceedings or claims will not have a material adverse effect on the Company’s consolidated financial position as a whole or on its liquidity, capital resources or future results of operations. The Company will continue to evaluate proceedings and claims involving the Company on a yearly basis and will establish and adjust any reserves as appropriate to reflect its assessment of the then current status of the matters.

E - MEMBERS’ EQUITY

The Company is owned by OZ Midstream Holdings, LLC (95%) (“OZ”) and Legion Energy, LLC (5%) (“Legion Energy”). The Company is managed by Legion Energy, the managing member. Legion Energy is owned by Zenergy Midstream, LLC (75%) (“Zenergy”) and Legion Energy Services, LLC (25%). The limited liability company interests are divided into the following four classes: Class A Interests, Class B Interests, Management Fee Interest and Carried Interest. Class A Interests and Class B Interests are issued on a series basis and correspond to individual projects with Class A Interests issued to OZ and Class B Interests issued to Legion Energy. The Class A and Class B Interests for the Arrow System constitute Series 1 interests (“Series 1 interests”). The Management Fee and the Carried Interests are solely economic interests and do not carry voting rights. Further, the Carried Interest is intended to be a “profits interest” within the meaning of IRS laws and is owned entirely by the Class B members. The members agreed to make the following capital contributions to fund the Company: up to $237,500 by the Class A member less the initial capital contribution plus any support contributions made on behalf of the Class B member; and up to $12,500 by the Class B member less its initial capital contribution.

Arrow Midstream Holdings, LLC and Subsidiaries

Notes to unaudited condensed consolidated financial statements - continued

(In thousands)

In accordance with the LLC Agreement and as requested by the Class B member, the Class A member is required to make primary support contributions on behalf of the Class B member until September 15, 2012, which is the end of the support period. These contributions, when made, satisfy the $12,500 capital commitment as discussed above. Each Class B member, as security for its obligation to repay the primary support contributions, pledges its proportionate share of Class B Interests as collateral in the event that its obligation is not fulfilled. The Class B member is required to repay the primary support contributions through deductions to future cash distributions.

During the nine months ended September 30, 2013, the following capital contributions, net of noncontrolling interest, were made by the members: $35,002 by the Class A member and $1,842 by the Class A member on behalf of the Class B member. During the year ended December 31, 2012, the following capital contributions, net of noncontrolling interest, were made by the members: $26,463 by the Class A member and $1,393 by the Class A member on behalf of the Class B member. A member is not entitled to the return of any part of its capital contribution and any unrepaid capital contribution is not a liability of the Company or any other member.

Income and loss allocations and dividend distributions are payable first to Class A and Class B members in proportion to their capital contributions for Series 1 interests until they have received an amount equal to their aggregate capital contributions plus an annual return on those capital contributions. Second, income allocations and dividend distributions are made to the holders of the Management Fee Interest in proportion to their capital contributions plus an annual return. Any remaining income or distributions are made in accordance with the LLC agreement. There have been no distributions in 2012 or for the nine months ended September 30, 2013.

On February 14, 2013, the members of APL entered into an amendment to the Amended and Restated Operating Agreement of Arrow Pipeline, LLC (“Agreement”). The February 2013 amendment, among other things, removed reference to a $5,000 cap on support contributions provided to MHA Holdings, LLC (“MHA”) along with the $1,000 cap on support for Bow Midstream Holdings, LLC. The support termination date was also extended to require support, if so requested, in connection with any future capital calls required by the managing member of APL. The buy-in option for MHA was amended to allow MHA to acquire up to a 20% ownership stake in APL after MHA repays its support.

F - RELATED PARTY TRANSACTIONS

Until October 2012, Legion Energy provided management, general and administrative services to the Company and its subsidiaries and was reimbursed by the Company for its proportionate share of those services, including office equipment and other necessary office expenses. During the nine months ended September 30, 2012, the Company incurred $2,927 of expenses under this arrangement.

In October 2012, Zenergy began providing management and general and administrative services to the Company and its subsidiaries paid. The Company paid Zenergy $240 for direct billings incurred during the remainder of the year ended December 31, 2012. The Company incurred $872 of expenses under this arrangement for management and general and administrative services for the nine months ended September 30, 2013.

During 2012, Zenergy began drilling a salt water disposal well for AW. As of December 31, 2012, total costs incurred were $667. Total costs incurred were $3,977 for the nine months ended September 30, 2013.

Arrow Midstream Holdings, LLC and Subsidiaries

Notes to unaudited condensed consolidated financial statements - continued

(In thousands)

The Company also paid certain expenditures on behalf of entities affiliated through common ownership and the Company has recorded related party receivables of $21 at December 31, 2012. There were no related party receivables at September 30, 2013.

During 2012, OZ agreed to satisfy an adequate assurance provision of one of the Company’s producers, on behalf of the Company, in the form of a letter of credit issued by Bank of America (“Bank”). OZ is responsible for the payment of certain fees and expenses related to the letter of credit to the Bank and the Company is then obligated to reimburse OZ for said expenses. The letter of credit was issued in the amount of $54,654 as of September 30, 2013.

G- CONCENTRATION OF CREDIT RISK

Substantially all the Company’s customers are oil and gas companies. This concentration of customers within a particular industry may impact the Company’s overall credit risk, either positively or negatively, in that these entities may be similarly affected by industry-wide changes in economic and other conditions.

For the nine months ended September 30, 2013, the Company had sales to four customers that accounted for approximately 11.6%, 14.5%, 15.9% and 35.0% of total sales and four customers that accounted for approximately 15.0%, 10.7%, 20.2% and 34.1% of the Company’s total receivables as of September 30, 2013. For the nine months ended September 30, 2012, the Company had sales to three customers that accounted for approximately 10.4%, 13.1% and 13.5% of total sales and four customers that accounted for approximately 10.5%, 14.7%, 16.2% and 17.0% of the Company’s total receivables as of September 30, 2012.

H - WATER SPILLS

In July 2012, the Company experienced two idiosyncratic ruptures in its produced water gathering line system. The Company immediately responded to contain the surface damage, worked cooperatively with all relevant authorities and engaged an environmental consultant to implement a comprehensive remediation plan. Additionally, the Company declared a force majeure event for its entire produced water system and took it out of service until the system could be properly repaired and tested. The Company worked with the vendor of the failed pipe to assess the probable cause of the events and engaged a third party lab to test sections of the ruptured pipe. After finalizing the root cause assessment, the Company developed a comprehensive plan to flush, re-hydrotest and recommission the entire produced water system. The water system was initially placed back in operation in December 2012 and the Company was beginning to phase water volumes back on to the system. As of December 31, 2012, the Company had incurred $2,911 of remediation and recommissioning expenses related to the water line rupture and had received net insurance payments after deductibles of $371. For the nine months ended September 30, 2013, the Company incurred $672 of remediation and recommissioning expenses and had received net insurance payments after deductibles of $231, related to the water line rupture. Management does not expect any significant additional costs related to the water line rupture.

Arrow Midstream Holdings, LLC and Subsidiaries

Notes to unaudited condensed consolidated financial statements - continued

(In thousands)

I - SUBSEQUENT EVENTS

Management has evaluated subsequent events through December 4, 2013, the date the financial statements were available to be issued. No subsequent events, other than those noted below, were identified requiring additional recognition or disclosure in the accompanying condensed consolidated financial statements.

On October 18, 2013, MHA elected to purchase an additional 2% interest in APL for total consideration of $5,671, bringing its total ownership in APL to 15%. MHA retains the option to purchase an incremental 5% interest in APL (1% per month cumulatively) over time, however MHA’s ownership in APL is capped at 20%.

On November 8, 2013, Crestwood Arrow Acquisition LLC (“Crestwood Arrow”), a wholly-owned subsidiary of Crestwood Midstream Partners LP, acquired the Company for approximately $750,000, subject to customary purchase price adjustments. Both the Credit Agreement and the capital lease agreement terminated in connection with the Crestwood Arrow acquisition. Crestwood Arrow paid off the $55,000 balance outstanding under the Credit Agreement, and the Company expensed the unamortized portion of the debt issuance costs of $1,251 at the November 8, 2013 closing date. Additionally, the Company paid the balance outstanding of $16,070 under the capital lease and incurred $2,036 in termination fees at the November 8, 2013 closing date.

EX-99.4

Exhibit 99.4

UNAUDITED PRO FORMA CONDENSED COMBINED CONSOLIDATED FINANCIAL INFORMATION

The merger (“Crestwood Merger”) of Crestwood Midstream Partners LP (“Legacy Crestwood” or “Legacy CMLP”) and Inergy Midstream, L.P. (“Inergy Midstream”) closed on October 7, 2013 and the name of the surviving entity, Inergy Midstream, L.P., was immediately thereafter changed to Crestwood Midstream Partners LP (“Crestwood Midstream”).

These following unaudited pro forma condensed combined consolidated financial statements of Crestwood Midstream (the “pro forma financial statements”) have been prepared for illustrative purposes only and are not necessarily indicative of what the combined partnership’s condensed consolidated financial position or results of operations actually would have been had the following tractions occurred as of the dates indicated: (i) the Crestwood Merger; (ii) the issuance by Inergy Midstream of 773,191 common units on October 7, 2013 immediately prior to the closing of the Crestwood Merger as a result of the underwriters exercising their option to purchase additional common units related to the issuance by Inergy Midstream of 11,000,000 common units on September 13, 2013 (“October Equity Offering”); and (iii) the acquisition (“Arrow Acquisition”) of 100% of the membership interests of Arrow Midstream Holdings, LLC (“Arrow”), which closed on November 8, 2013. In addition, the unaudited pro forma condensed combined consolidated financial information does not purport to project the future financial position or operating results of the combined partnership. Future results may vary significantly from the results reflected because of various factors.

The unaudited pro forma condensed combined consolidated balance sheet as of September 30, 2013 reflects the Crestwood Merger, October Equity Offering and Arrow Acquisition as if they occurred on September 30, 2013 and the unaudited pro forma condensed combined consolidated statements of operations for the year ended December 31, 2012 and the nine months ended September 30, 2013 reflect the Crestwood Merger, October Equity Offering and Arrow Acquisition as if they occurred on January 1, 2012. The pro forma financial statements reflect the following:

• the closing of the Arrow Acquisition for a purchase price of $750 million, $200 million of which was funded by the issuance to the sellers of 8,826,125 common units of Crestwood Midstream;

• the issuance of 14,000,000 Crestwood Midstream common units on October 17, 2013 (“Arrow Equity Offering”), which generated proceeds of $296.4 million used to finance a portion of the Arrow Acquisition;

• the issuance of 2,100,000 Crestwood Midstream common units on October 30, 2013, as a result of the underwriters exercising their option to purchase additional common units related to the Arrow Equity Offering. This generated proceeds of $44.5 million, which were used to finance a portion of the Arrow Acquisition;

• the issuance by Crestwood Midstream of $600 million of Senior Notes due 2022 (“Senior Notes”) used to finance a portion of the Arrow Acquisition and to reduce a portion of the revolving credit facility;

• payment of certain non-recurring contractual financing and professional fees related to the Arrow Acquisition estimated at approximately $19.1 million, including $10.5 million of costs related to the Senior Notes;

• the conversion of each Legacy CMLP common unit issued and outstanding as of the effective time of the Crestwood Merger (i) owned by Legacy Crestwood unitholders (other than certain Crestwood affiliated entities) into the right to receive $1.03 in cash and 1.0700 Inergy Midstream common units and (ii) owned by certain Crestwood affiliated entities into the right to receive only 1.0700 Inergy Midstream common units;

• Inergy Midstream’s payment of all cash consideration relating to the Crestwood Merger consideration payable at the effective time of the Crestwood Merger, other than approximately $10.4 million, which amount was funded by Crestwood Holdings;

• payment of certain estimated non-recurring contractual financing and professional fees related to the Crestwood Merger;

• payment of non-recurring fees associated with entering into our new $1 billion revolving credit facility: and

• the issuance by Inergy Midstream of 773,191 common units on October 7, 2013 immediately prior to the closing of the Crestwood Merger as a result of the underwriters exercising their option to purchase additional common units related to an equity offering that occurred on September 13, 2013.

Descriptions of the foregoing adjustments are presented in the notes to the pro forma financial statements provided below. The fiscal year end for the pro forma financial statements is December 31.

The pro forma financial statements were derived from and should be read in conjunction with the historical financial statements of legacy Crestwood, Inergy Midstream and Arrow for the applicable periods indicated as filed with the Securities and Exchange Commission. The pro forma condensed combined balance sheet and the pro forma condensed combined statements of operations were derived by adjusting historical financial statements based on currently available information and, therefore, the actual adjustments may materially differ from the pro forma adjustments.

The Crestwood Merger will be accounted for as a reverse acquisition of Inergy Midstream by Legacy CMLP under the purchase method of accounting in accordance with FASB Accounting Standard Codification Subtopic 805-Business Combinations. The accounting for a reverse merger results in the legal acquiree (Legacy CMLP) being the acquiror for accounting purposes. Therefore, the Partnership will account for the merger as if Legacy CMLP acquired Inergy Midstream. The assets and liabilities of Inergy Midstream will be reflected at fair value on the balance sheet of the combined partnership. The fair value of the assets and liabilities is based on the enterprise value of Inergy Midstream as of June 19, 2013 (the date in which Legacy CMLP and Inergy Midstream came under common control). A final determination of the purchase accounting adjustments, including the allocation of fair value to the Inergy Midstream assets and liabilities, has not been made. Accordingly, the purchase accounting adjustments made in connection with the development of the pro forma financial statements are preliminary and have been made solely for purposes of developing such pro forma financial statements. The pro forma financial statements do not purport to present the Partnership’s financial position or the results of operations had the merger transactions actually been completed as of the dates indicated. Further, these pro forma financial statements do not reflect the effects of any cost savings or other synergies that may be achieved as a result of the Crestwood Merger, are based on assumptions that Crestwood Midstream believes are reasonable under the circumstances, and are intended for informational purposes only. Moreover, the statements do not project Crestwood Midstream’s financial position or results of operations for any future date or period.

The Arrow Acquisition will be accounted for as an acquisition under the purchase method of accounting in accordance with Financial Accounting Standard Board (“FASB”) Accounting Standard Codification Subtopic 805-10 (“805-10”). The assets and liabilities of Arrow will be reflected at fair value. A final determination of the purchase accounting adjustments, including the allocation of the purchase price of the assets acquired and liabilities assumed based on their fair values, has not been made. Accordingly, the purchase accounting adjustments made in connection with the development of the following unaudited pro forma condensed combined consolidated financial statements are preliminary and have been made solely for purposes of developing such unaudited pro forma condensed combined consolidated financial statements. The unaudited pro forma condensed combined consolidated financial statements do not purport to present the financial position or results of operations of Crestwood Midstream had the Arrow Acquisition actually been completed as of the dates indicated. Further, these unaudited pro forma condensed combined consolidated financial statements do not reflect the effects of any cost savings or other synergies that may be achieved as a result of this transaction, are based on assumptions that Crestwood Midstream believes are reasonable in the circumstances, and are intended for informational purposes only. Moreover, the statements do not project the financial position or results of operations of Crestwood Midstream for any future date or period.

CRESTWOOD MIDSTREAM PARTNERS LP

UNAUDITED PRO FORMA CONDENSED COMBINED CONSOLIDATED BALANCE SHEET

AS OF SEPTEMBER 30, 2013

(in millions)

	Historical									Historical
	Crestwood Midstream Partners LP		Inergy Midstream, L.P.		Crestwood Midstream Partners LP Merger Pro Forma Adjustments (b)			Crestwood Midstream Partners LP Pro Forma		Arrow Midstream Holdings, LLC		Arrow Midstream Holdings, LLC Pro Forma Adjustments				Crestwood Midstream Partners LP Pro Forma, As Further Adjusted
Assets
Current assets:
Cash and cash equivalents	$	5.7	$	1.2	$	(54.1	)	$	5.7	$	14.6	$	(550.0	)	(a)	$	20.3
						52.9							340.9		(c)
													600.0		(d)
													(19.1	)	(e)
						—							(371.8	)	(f)
Accounts receivable		27.7		26.3		—			54.0		148.8						202.8
Accounts receivable - related party		24.0		1.2		—			25.2		—						25.2
Insurance receivable		3.1		—		—			3.1		—						3.1
Inventories		—		5.9		—			5.9		1.0						6.9
Prepaid expenses and other current assets		0.8		4.6		—			5.4		1.0						6.4
Total current assets		61.3		39.2		(1.2	)		99.3		165.4		—				264.7
Property, plant and equipment, net		1,144.9		982.8		690.3			2,818.0		229.8		125.0		(a)		3,172.8
Intangible assets, net		428.9		172.8		(13.3	)		603.4		—		382.1		(a)		996.0
						15.0							10.5		(e)
Goodwill		99.6		259.6		1,082.6			1,441.8		—		—				1,441.8
Investment in unconsolidated affiliate		127.6		24.4					152.0								152.0
Other assets		21.7		4.3		24.5			50.5		17.9						68.4
Total assets	$	1,884.0	$	1,483.1	$	1,797.9		$	5,165.0	$	413.1	$	517.6			$	6,095.7

CRESTWOOD MIDSTREAM PARTNERS LP

UNAUDITED PRO FORMA CONDENSED COMBINED CONSOLIDATED BALANCE SHEET

AS OF SEPTEMBER 30, 2013

(in millions)

	Historical									Historical
	Crestwood Midstream Partners LP		Inergy Midstream, L.P.		Crestwood Midstream Partners LP Merger Pro Forma Adjustments (b)			Crestwood Midstream Partners LP Pro Forma		Arrow Midstream Holdings, LLC		Arrow Midstream Holdings, LLC Pro Forma Adjustments				Crestwood Midstream Partners LP Pro Forma, As Further Adjusted
Liabilities and partners’ capital
Current liabilities:
Accounts payable, accrued expenses and other liabilities	$	41.0	$	20.8	$	—		$	61.8	$	166.5					$	228.3
Accounts payable - related party		4.5		—		—			4.5		—						4.5
Accrued additions to property, plant and equipment		41.3		9.2		—			50.5		—						50.5
Capital leases		3.0		—		—			3.0		—		—				3.0
Deferred revenue		2.4		—		—			2.4		—						2.4
Current portion of long-term debt		—		—		—			—		51.2		(51.2	)	(a)		—
Total current liabilities		92.2		30.0		—			122.2		217.7		(51.2	)			288.7
Long-term debt, less current portion		899.4		537.0		5.0			1,477.5		—		600.0		(d)		1,705.7
						52.9							(371.8	)	(f)
						(16.8	)
Long-term capital leases		1.3		—		—			1.3		—						1.3
Asset retirement obligations		14.6		—		—			14.6		—						14.6
Other long-term liabilities		—		0.8		—			0.8		3.7						4.5
																	—
Partners’ capital		778.5		915.3		1,779.1			3,450.6		191.7		540.9		(c)		3,982.9
						(39.1	)						(191.7	)	(a)
						16.8							(8.6	)	(e)
Non controlling interests - preferred equity of subsidiary		98.0							98.0								98.0
Total partners’ capital		876.5		915.3		1,756.8			3,548.6		191.7		340.6				4,080.9
Total liabilities and partners’ capital	$	1,884.0	$	1,483.1	$	1,797.9		$	5,165.0	$	413.1	$	517.6			$	6,095.7

The accompanying notes are an integral part of these unaudited pro forma condensed combined consolidated financial statements.

CRESTWOOD MIDSTREAM PARTNERS LP

UNAUDITED PRO FORMA CONDENSED COMBINED CONSOLIDATED STATEMENTS OF OPERATIONS

FOR THE YEAR ENDED DECEMBER 31, 2012

(in millions, except unit and per unit information)

	Historical															Historical
	Crestwood Midstream Partners LP		Inergy Midstream, L.P. (1)		Rangeland Energy, LLC Acquisition (g)			Inergy Midstream, L.P. Pro Forma			Crestwood Midstream Partners LP Merger Pro Forma Adjustments (b)			Crestwood Midstream Partners LP, As Further Adjusted		Arrow Midstream Holdings, LLC		Arrow Midstream Holdings, LLC Pro Forma Adjustments				Crestwood Midstream Partners LP Pro Forma, As Further Adjusted
Revenues	$	239.5	$	189.8	$	3.4		$	193.2		$	—		$	432.7	$	735.1	$	—			$	1,167.8
Depreciation, amortization, and accretion expense		51.9		50.5		35.3			85.8			(16.9	)		120.8		5.0		28.7		(h)		154.5
Other operating expenses		111.7		71.8		5.1			76.9			—			188.6		723.6		—				912.2
Operating income (loss)		75.9		67.5		(37.0	)		30.5			16.9			123.3		6.5		(28.7	)			101.1
Interest and debt expense		35.8		1.8		24.6			26.4			(0.5	)		61.7		0.1		30.5		(i)		92.3
Other income		—		—		0.1			0.1			—			0.1		0.4		—				0.5
Income (loss) before income taxes		40.1		65.7		(61.5	)		4.2			17.4			61.7		6.8		(59.2	)			9.3
Provision for income taxes		1.2		—		—			—			—			1.2		—		—				1.2
Net income (loss)		38.9		65.7		(61.5	)		4.2			17.4			60.5		6.8		(59.2	)			8.1
Less: net income prior to initial public offering of Inergy Midstream, L.P.		—		12.9		—			12.9			—			12.9		—		—				12.9
Less: net income earned by US Salt, LLC prior to acquisition		—		7.8		—			7.8			—			7.8		—		—				7.8
Less: net income attributable to non-controlling interests		—		—		—			—			—			—		0.6		—				0.6
Net income (loss) available to partners	$	38.9	$	45.0	$	(61.5	)	$	(16.5	)	$	17.4		$	39.8	$	6.2	$	(59.2	)		$	(13.2	)
Partners’ interest information:
General partner interest in net income	$	22.2	$	1.9	$	—		$	1.9		$	—		$	24.1	$	—	$	—			$	24.1

CRESTWOOD MIDSTREAM PARTNERS LP

UNAUDITED PRO FORMA CONDENSED COMBINED CONSOLIDATED STATEMENTS OF OPERATIONS

FOR THE YEAR ENDED DECEMBER 31, 2012

(in millions, except unit and per unit information)

	Historical															Historical
	Crestwood Midstream Partners LP		Inergy Midstream, L.P. (1)		Rangeland Energy, LLC Acquisition (g)			Inergy Midstream, L.P. Pro Forma			Crestwood Midstream Partners LP Merger Pro Forma Adjustments (b)			Crestwood Midstream Partners LP, As Further Adjusted		Arrow Midstream Holdings, LLC		Arrow Midstream Holdings, LLC Pro Forma Adjustments				Crestwood Midstream Partners LP Pro Forma, As Further Adjusted
Total limited partners’ interest in net income (loss)	$	16.7	$	43.1	$	(61.5	)	$	(18.4	)	$	17.4		$	15.7	$	6.2	$	(59.2	)		$	(37.3	)
Net income (loss) per limited partner unit:
Basic	$	0.37	$	0.58				$	(0.21	)				$	0.10							$	(0.22	)
Diluted	$	0.37	$	0.58				$	(0.21	)				$	0.10							$	(0.22	)
Weighted average limited partners’ units outstanding (in thousands):
Basic		45,223		74,768		10,714			85,482			65,429	(i)		150,911				24,926		(k)		175,837
Diluted		45,420		74,768		10,714			85,482			65,429	(i)		150,911				24,926		(k)		175,837
Dividends declared per limited partner unit	$	2.02	$	1.18																	(l)	$	1.04

(1) The Inergy Midstream, L.P. financial information is for the year ended September 30, 2012.

The accompanying notes are an integral part of these unaudited pro forma condensed combined consolidated financial statements.

CRESTWOOD MIDSTREAM PARTNERS LP

UNAUDITED PRO FORMA CONDENSED COMBINED CONSOLIDATED STATEMENTS OF OPERATIONS

FOR THE NINE MONTHS ENDED SEPTEMBER 30, 2013

(in millions, except unit and per unit information)

	Historical												Historical
	Crestwood Midstream Partners LP			Inergy Midstream, L.P.			Crestwood Midstream Partners LP Merger Pro Forma Adjustments (b)			Crestwood Midstream Partners LP Pro Forma			Arrow Midstream Holdings, LLC		Arrow Midstream Holdings, LLC Pro Forma Adjustments				Crestwood Midstream Partners LP Pro Forma, As Further Adjusted
Revenues	$	214.7		$	203.3		$	—		$	418.0		$	1,108.9	$	—			$	1,526.9
Depreciation, amortization, and accretion expense		49.6			76.3			(16.7	)		109.2			4.6		21.5		(h)		135.3
Other operating expenses		109.4			98.5			—			207.9			1,085.5		—				1,293.4
Goodwill impairment		(4.1	)		—						(4.1	)								(4.1	)
Gain on sale of assets		4.4			—						4.4									4.4
Operating income		56.0			28.5			16.7			101.2			18.8		(21.5	)			98.5
Loss from unconsolidated affiliate		(0.5	)								(0.5	)								(0.5	)
Interest and debt expense		34.3			27.2			(4.2	)		57.3			0.7		20.4		(i)		78.4
Other income (expense)		—			—			—			—			0.2						0.2
Income before income taxes		21.2			1.3			20.9			43.4			18.3		(41.9	)			19.8
Provision for income taxes		1.0			0.1			—			1.1			—						1.1
Net income	$	20.2		$	1.2		$	20.9		$	42.3		$	18.3	$	(41.9	)		$	18.7
Less: net income attributable to non-controlling interests		1.9			—			—			1.9			1.3		—				3.2
Net income attributable to partners		18.3			1.2			20.9			40.4			17.0		(41.9	)			15.5
Partners’ interest information:
General partner interest in net income	$	10.5		$	11.0		$	—		$	21.5		$	—	$	—			$	21.5
Total limited partners’ interest in net income	$	7.8		$	(9.8	)	$	20.9		$	18.9		$	17.0	$	(41.9	)		$	(6.0	)
Net income per limited partner unit:
Basic	$	0.13		$	(0.11	)				$	0.12								$	(0.04	)
Diluted	$	0.13		$	(0.11	)				$	0.12								$	(0.04	)
Weighted average limited partners’ units outstanding (in thousands):
Basic		58,339			89,618			65,429	(i)		155,047					24,926		(k)		179,973
Diluted		58,608			89,618			65,429	(i)		155,047					24,926		(k)		179,973
Dividends declared per limited partner unit	$	1.02		$	1.19													(l)	$	1.16

The accompanying notes are an integral part of these unaudited pro forma condensed combined consolidated financial statements.

NOTES TO UNAUDITED PRO FORMA CONDENSED

COMBINED CONSOLIDATED FINANCIAL STATEMENTS

(a) Reflects the total purchase price of $750 million ($200 million of which was funded by units issued directly to the sellers) for Crestwood Midstream’s acquisition of 100% of the membership interests in Arrow Midstream Holdings, LLC (“Arrow Acquisition”). The excess of the purchase price over the net assets acquired was allocated to intangible assets on a preliminary basis, for which the preliminary amortization period is 17 years. Because this allocation was based on preliminary information, the purchase accounting adjustments made and the related amortization period in connection with the development of the unaudited pro forma condensed combined consolidated financial statements are preliminary and subject to material change.

The preliminary allocation of the purchase price is as follows (in millions):

	Historical Net Book Value			Adjustment		Preliminary Fair Value
Current assets	$	165.4		$	—	$	165.4
Property, plant and equipment, net		229.8			125.0		354.8
Intangible assets, net		—			382.1		382.1
Other assets		17.9			—		17.9
Current liabilities		(217.7	)		51.2		(166.5	)
Long-term debt		—			—		—
Other long-term liabilities		(3.7	)		—		(3.7	)
Total assumed purchase price	$	191.7		$	558.3	$	750.0

(b) The Merger of Legacy Crestwood and Inergy Midstream closed on October 7, 2013. The Merger will be accounted for as a reverse acquisition of Inergy Midstream under the purchase method of accounting in accordance with FASB Accounting Standard Codification Subtopic 805- Business Combinations. The accounting for a reverse merger results in the legal acquiree (Legacy Crestwood) being the acquiror for accounting purposes. Therefore, Inergy Midstream will be reflected at fair value on the balance sheet of the combined partnership. The fair value of the assets and liabilities of Inergy Midstream is based on the enterprise value of Inergy Midstream as of June 19, 2013 (the date in which Legacy Crestwood and Inergy Midstream came under common control). A final determination of the purchase accounting, including the allocation of fair value to the Inergy Midstream assets and liabilities, has not yet been made. Accordingly, the purchase accounting adjustments made in connection with the development of the pro forma financial statements are preliminary and have been made solely for the purposes of developing such pro forma financial statements.

(c) Reflects the issuance of $540.9 million of Crestwood Midstream common units to partially fund the Arrow Acquisition. $200 million of these common units were issued directly to the sellers.

(d) Reflects the issuance of $600 million of Senior Notes due 2022 (“Senior Notes”) to partially fund the Arrow Acquisition. A portion of these proceeds are also reflected as a reduction of the revolving credit facility in these pro forma financial statements.

(e) Reflects payments of $19.1 million for transaction costs related to the Arrow Acquisition, including $10.5 million associated with the issuance of the Senior Notes.

(f) Reflects the reduction of the revolving credit facility using combined proceeds from the issuance of the Arrow and October Equity Offerings and the issuance of the Senior Notes in excess of the Arrow Acquisition purchase price.

Unaudited Pro Forma Condensed Combined Consolidated Statements of Operations Adjustments

(g) Inergy Midstream acquired Rangeland Energy, LLC on December 7, 2012. These amounts have been calculated after applying Inergy Midstream’s accounting policies and adjusting the results of Rangeland Energy, LLC to reflect the depreciation and amortization that would have been charged assuming the preliminary fair value adjustments to property, plant and equipment and intangible assets had been made at the beginning of the current period. These amounts include the funding of the acquisition, which included the issuance of 10.7 million limited partner units for $225.0 million and the issuance of $500.0 million of senior notes. These amounts were used to fund the $425.0 million acquisition and pay down $300 million in revolver debt. The entities comprising Rangeland Energy, LLC were development stage entities (as defined by ASC Topic 915, Development Stage Entities) until commencing principal commercial operations in June 2012.

(h) Reflects the pro forma adjustment of depreciation and amortization expense as follows (in millions):

	December 31, 2012		September 30, 2013
Pro forma depreciation and amortization expense on property, plant and equipment and intangible assets	$	28.7	$	21.5
Pro forma adjustment to depreciation and amortization expense	$	28.7	$	21.5

The preliminary purchase allocation includes $382.1 million of intangible assets, for which the preliminary amortization period is 17 years. Because this allocation was based on preliminary information, the purchase accounting adjustments made and the related amortization period are subject to material change. A decrease of 1 year in the estimated amortization period would result in increased amortization expense of $1.4 million for the year ended December 31, 2012 and $1.1 million for the nine months ended September 30, 2013, respectively.

The preliminary purchase allocation also includes $125.0 million of an adjustment to the historical basis of the acquired property, plant and equipment, for which the depreciable life was determined to be 20 years.

(i) Reflects the pro forma adjustment of interest and debt expense as follows (in millions):

	December 31, 2012			September 30, 2013
Interest on additional borrowings to fund the Arrow Acquisition and related transaction costs.	$	36.8		$	27.6
Remove historical interest expense of Arrow	$	(0.1	)	$	(0.7	)
Amortization of new deferred financing costs associated with the Senior Notes	$	1.3		$	1.0
Remove historical interest expense arising from the reduction of the revolving credit facility	$	(7.5	)	$	(7.5	)
Pro forma adjustment to interest expense	$	30.5		$	20.4

The interest rate on the Senior Notes is 6.125%. An increase of 20 basis points in this interest rate would increase the interest and debt expense by approximately $1.2 million for the year ended December 31, 2012 and $0.9 million for the nine months ended September 30, 2013, respectively.

(j) Reflects the pro forma adjustment of basic and diluted weighted average shares outstanding following completion of the Crestwood Merger as follows (in thousands):

	December 31, 2012		September 30, 2013
Basic and diluted weighted average number of Inergy Midstream units outstanding—as reported		85,482		89,618
Inergy Midstream common units issued as merger consideration		64,656		64,656
Additional common units issued as a result of the underwriters exercising their option under the September Equity Offering		773		773
Pro forma basic and diluted weighted average number of Inergy Midstream units outstanding		150,911		155,047

(k) Reflects the pro forma adjustment of basic and diluted weighted average shares outstanding following the Arrow Acquisition (in thousands):

	December 31, 2012		September 30, 2013
Basic and diluted weighted average number of Inergy Midstream units outstanding - Pro Forma for the Crestwood Merger		150,911		155,047
Crestwood Midstream common units issued as consideration for Arrow Acquisition		24,926		24,926
Pro forma basic and diluted weighted average number of Crestwood Midstream units outstanding		175,837		179,973

(l) Reflects pro forma distributions declared per limited partner unit following the completion of the Crestwood Merger and Arrow Acquisition as follows:

	December 31, 2012		September 30, 2013
Dividends declared (in millions) (1)	$	182.9	$	208.1
Pro forma weighted average limited partners’ units outstanding (in thousands)		175,837		179,973
Pro forma dividends declared per limited partner unit	$	1.04	$	1.16

(1) Represents historical dividends of Legacy Crestwood and Inergy Midstream.