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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,										Quarter Ended March 31,
		2004		2005		2006		2007		2008		2009
Fixed Charges		17,192		34,080		54,153		49,191		86,559		25,119
Earnings		22,942		28,221		122,690		(7,299	)	352,140		(18,317	)
Add:
	(a) Pre-tax income from continuing operations	6,490		(8,515	)	74,498		(59,155	)	273,602		(39,007	)
	(b) Fixed charges	17,192		34,080		54,153		49,191		86,559		25,119
	(c) Amortization of capitalized interest	53		195		255		478		1,110		359
	(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	)	105
Subtract
	(a) Interest capitalized	(793	)	(2,133	)	(900	)	(3,344	)	(9,486	)	(4,893	)
Equals Earnings		22,942		28,221		122,690		(7,299	)	352,140		(18,317	)
Ratio		1.33		0.83		2.27		(0.15	)	4.07		(0.73	)

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Exhibit 12.1