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Exhibit 23.1
CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
We hereby consent to the incorporation by reference in this Registration Statement on Form S-3 of our report dated March 15, 2004 relating to the financial statements, which appears in MarkWest Energy Partners, L.P.'s 2003 Annual Report on Form 10-K for the year ended December 31, 2003. We also consent to the reference to us under the heading "Experts" in such Registration Statement.
PricewaterhouseCoopers LLP
Denver, CO
June 21, 2004
CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM