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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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<SEC-DOCUMENT>9999999995-09-003040.txt : 20091105
<SEC-HEADER>9999999995-09-003040.hdr.sgml : 20091105
<ACCEPTANCE-DATETIME>20091105001515
ACCESSION NUMBER:		9999999995-09-003040
CONFORMED SUBMISSION TYPE:	EFFECT
PUBLIC DOCUMENT COUNT:		1
FILED AS OF DATE:		20091019
DATE AS OF CHANGE:		20091105
EFFECTIVENESS DATE:		20091019

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			MARKWEST ENERGY PARTNERS L P
		CENTRAL INDEX KEY:			0001166036
		STANDARD INDUSTRIAL CLASSIFICATION:	CRUDE PETROLEUM & NATURAL GAS [1311]
		IRS NUMBER:				270005456
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		EFFECT
		SEC ACT:		1933 Act
		SEC FILE NUMBER:	333-160420
		FILM NUMBER:		091159326

	BUSINESS ADDRESS:	
		STREET 1:		1515 ARAPAHOE STREET
		STREET 2:		TOWER 2, SUITE 700
		CITY:			DENVER
		STATE:			CO
		ZIP:			80202-2126
		BUSINESS PHONE:		303-925-9200

	MAIL ADDRESS:	
		STREET 1:		1515 ARAPAHOE STREET
		STREET 2:		TOWER 2, SUITE 700
		CITY:			DENVER
		STATE:			CO
		ZIP:			80202-2126
</SEC-HEADER>
<DOCUMENT>
<TYPE>EFFECT
<SEQUENCE>1
<FILENAME>primary_doc.xml
<TEXT>
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<?xml version="1.0"?>
<edgarSubmission>

    <schemaVersion>X0101</schemaVersion>

    <submissionType>EFFECT</submissionType>

    <act>33</act>

    <testOrLive>LIVE</testOrLive>

    <effectiveData>
        <finalEffectivenessDispDate>2009-10-19</finalEffectivenessDispDate>
        <finalEffectivenessDispTime>17:00:00</finalEffectivenessDispTime>
        <form>S-4</form>
        <filer>
            <cik>0001166036</cik>
            <entityName>MARKWEST ENERGY PARTNERS L P</entityName>
            <fileNumber>333-160420</fileNumber>
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</XML>
</TEXT>
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