Asset Retirement Obligations

12 Months Ended

Dec. 31, 2012

Asset Retirement Obligation Disclosure [Abstract]

Asset Retirement Obligations

ASSET RETIREMENT OBLIGATIONS

At December 31, 2012 and December 31, 2011, the total undiscounted amount of the estimated future cash needs was estimated to be $73.4 million and $72.8 million, respectively. Discount rates used to value the ARO range between 8% and 10%. The schedule of payments required to settle the December 31, 2011 ARO liability extends through 2029.

The changes in the carrying amount of the ARO during the years ended December 31, 2012, and December 31, 2011, are as follows:

	For the years ended December 31,
	2012			2011
Beginning balance	$	33,880		$	44,952
Accretion expense	2,816			3,845
Additions and changes in estimates	3,620			11,978
Cost of reclamation work performed	(6,203		)	(26,895		)
Balance at December 31	$	34,113		$	33,880
Current portion	$	9,943		$	8,996
Long term portion	$	24,170		$	24,884