Asset Retirement Obligation

3 Months Ended

Mar. 31, 2012

(12) Asset Retirement Obligation

The following table presents the activity in the Company's asset retirement obligation for the three months ended March 31, 2012, and for the year ended December 31, 2011 (in thousands):

	Three Months Ended March 31, 2012			Year Ended December 31, 2011

Balance at beginning of period	$	15,541		$	12,471
Obligations settled		(124	)		(1,030	)
Accretion expense		251			955
Revisions in estimated cash flows		1,919			2,508
Gain on settlement		—			637

Balance at end of period	$	17,587		$	15,541

The Company is required to provide the applicable governmental agencies with financial assurances relating to its closure and reclamation obligations. At March 31, 2012, the Company had financial assurance requirements of $28.8 million, which were satisfied with surety bonds placed with California state and regional agencies.

- Definition

The entire disclosure for an asset retirement obligation and the associated long-lived asset. An asset retirement obligation is a legal obligation associated with the disposal or retirement from service of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

+ References+ Details