10. Income Taxes

The Company has not recognized any income tax provision (benefit) for the three and six months ended June 30, 2013 and 2012 due to continuing losses from operations.

The U.S. statutory federal income tax rate is reconciled to the Company’s effective income tax rate as follows (in thousands):

	Three Months Ended June 30,				Six Months Ended June 30,
	2013		2012		2013		2012
Tax benefit at 35% federal statutory rate	$	1,658	$	4,345	$	3,523	$	8,228
State tax benefit, net of federal benefit		24		62		50		117
Noncontrolling interest		(218)		(651)		(464)		(1,249)
Valuation allowance		(1,420)		(3,732)		(2,957)		(6,783)
Other		(44)		(24)		(152)		(313)
Total	$	—	$	—	$	—	$	—

The effects of temporary differences and other items that give rise to deferred tax assets and liabilities are presented below (in thousands):

	June 30, 2013		December 31, 2012
Deferred tax assets:
Capitalized start up costs	$	3,033	$	3,253
Stock-based compensation		965		965
Net operating loss carryover		87,514		84,960
Other		268		266
Deferred tax assets		91,780		89,444
Valuation allowance		(50,501)		(47,544)

Deferred tax liabilities:
Property, plant and equipment		(41,279)		(41,900)
Deferred tax liabilities		(41,279)		(41,900)
Net deferred tax asset	$	—	$	—

The Company assesses the recoverability of deferred tax assets and the need for a valuation allowance on an ongoing basis. In making this assessment, management considers all available positive and negative evidence to determine whether it is more likely than not that some portion or all of the deferred tax assets will be realized in future periods. This assessment requires significant judgment and estimates involving current and deferred income taxes, tax attributes relating to the interpretation of various tax laws, historical bases of tax attributes associated with certain assets and limitations surrounding the realization of deferred tax assets.

As of June 30, 2013, the net operating loss carryforward was $246.0 million, which will begin to expire if not used by December 31, 2028. The U.S. federal statute of limitations remains open for our 2009 and subsequent tax years.