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Exhibit 12.1

CLOUD PEAK ENERGY INC. AND SUBSIDIARIES

COMPUTATION OF HISTORICAL RATIOS OF EARNINGS TO FIXED CHARGES(1)

(In Thousands, Except Ratio Data)

		Six Months Ended June 30, 2011			2010			2009			2008			2007			2006
Earnings:
Income from continuing operations before income taxes and earnings from unconsolidated affiliates		$	65,568		$	145,990		$	249,340		$	109,140		$	69,377		$	53,689
	Amortization of capitalized interest		684			1,369			1,363			1,342			1,245			934
	Distributions of income from equity investments		2,000			35			4,000			4,750			—			—
	Capitalized interest		(16,886	)		(24,492	)		(15,484	)		(6,558	)		(1,802	)		(5,013	)
	Fixed charges		37,684			71,816			22,038			27,366			43,325			44,152
Adjusted income from continuing operations before income tax provision		$	89,050		$	194,717		$	261,257		$	136,040		$	112,145		$	93,762
Fixed charges:
	Interest expense	$	20,672		$	46,938		$	5,992		$	20,376		$	40,930		$	38,785
	Capitalized interest		16,886			24,492			15,484			6,558			1,802			5,013
	Interest within rental expense		126			386			562			432			593			354
Total fixed charges		$	37,684		$	71,816		$	22,038		$	27,366		$	43,325		$	44,152
Ratio of earnings to fixed charges			2.4x			2.7x			11.9x			5.0x			2.6x			2.1x

CLOUD PEAK ENERGY RESOURCES LLC AND SUBSIDIARIES

		Six Months Ended June 30, 2011			2010			2009			2008			2007			2006
Earnings:
Income from continuing operations before income taxes and earnings from unconsolidated affiliates		$	108,301		$	165,728		$	249,340		$	109,140		$	69,377		$	53,689
	Amortization of capitalized interest		684			1,369			1,363			1,342			1,245			934
	Distributions of income from equity investments		2,000			35			4,000			4,750			—			—
	Capitalized interest		(16,886	)		(24,492	)		(15,484	)		(6,558	)		(1,802	)		(5,013	)
	Fixed charges		37,684			71,816			22,038			27,366			43,325			44,152
Adjusted income from continuing operations before income tax provision		$	131,783		$	214,455		$	261,257		$	136,040		$	112,145		$	93,762
Fixed charges:
	Interest expense	$	20,672		$	46,938		$	5,992		$	20,376		$	40,930		$	38,785
	Capitalized interest		16,886			24,492			15,484			6,558			1,802			5,013
	Interest within rental expense		126			386			562			432			593			354
Total fixed charges		$	37,684		$	71,816		$	22,038		$	27,366		$	43,325		$	44,152
Ratio of earnings to fixed charges			3.5x			3.0x			11.9x			5.0x			2.6x			2.1x

(1)

For purposes of calculating the ratio of earnings to fixed charges, earnings were calculated by adding (i) earnings from continuing operations before income taxes and earnings from unconsolidated affiliates, (ii) net interest expense, including the portion of rents representative of an interest factor, (iii) amortization of debt issue costs and capitalized interest, (iv) distributions from equity investments and (v) capitalized interest. Fixed charges consist of net interest expense, amortization of debt issue costs and capitalized interest, and the portions of rents representative of an interest factor.

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Exhibit 12.1