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CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
We consent to the incorporation by reference in this Registration Statement on Form S-3 of our reports dated March 2, 2009, relating to the consolidated financial statements of MarkWest Energy Partners, L.P. and subsidiaries, and 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
March 12, 2009
CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM