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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,															Nine Months ended September 30,
		2003			2004			2005			2006			2007			2008
Fixed Charges			7,184			17,192			34,080			54,153			49,191			63,007
Earnings
Add:
	(a) Pre-tax income (loss) from continuing operations		(32,517	)		6,490			(8,515	)		74,498			(59,155	)		41,121
	(b) Fixed charges		7,184			17,192			34,080			54,153			49,191			63,007
	(c) Amortization of capitalized interest		—			53			195			255			478			610
	(d) Distributed income of equity investees		—			—			2,441			—			10,840			5,445
	(e) Share of pre-tax losses of equity investees		—			—			2,153			(5,316	)		(5,309	)		(1,932	)
Subtract:
	(a) Interest capitalized		—			(793	)		(2,133	)		(900	)		(3,344	)		(5,035	)
	(b) Preference security dividend requirements of consolidated subsidiaries		—			—			—			—			—			—
	(c) Minority interest in pre-tax income of subsidiaries that have not incurred fixed charges		—			—			—			—			—			—
Equals Earnings (Loss)			(25,333	)		22,942			28,221			122,690			(7,299	)		103,216
Ratio			(3.53	)		1.33			0.83			2.27			(0.15	)		1.64

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MarkWest Energy Partners, L.P. Calculation of Earnings to Fixed Charges