ASSET RETIREMENT OBLIGATIONS (Tables)

3 Months Ended

Mar. 31, 2013

Asset Retirement Obligations Operating Costs

For the three month periods ended March 31, we recognized ARO operating costs related to accretion of the liabilities and depreciation of the assets as follows:

	Three Months Ended March 31
in thousands	2013		2012
ARO Operating Costs
Accretion		$2,006		$2,019
Depreciation		779		1,864
Total		$2,785		$3,883

Reconciliations of Asset Retirement Obligations

Reconciliations of the carrying amounts of our AROs are as follows:

	Three Months Ended March 31
in thousands	2013			2012
Asset Retirement Obligations
Balance at beginning of period		$150,072			$153,979
Liabilities incurred		0			0
Liabilities settled		(1,292	)		(621	)
Accretion expense		2,006			2,019
Revisions up (down), net		5,672			25
Balance at end of period		$156,458			$155,402