Asset Retirement Obligations

9 Months Ended

Sep. 30, 2012

Asset Retirement Obligation [Abstract]

Asset Retirement Obligations

Note 5 - Asset Retirement Obligations

Questar records an asset retirement obligation (ARO) when there is a legal obligation associated with the retirement of a tangible long-lived asset. At Questar, AROs apply primarily to abandonment costs associated with gas and oil wells, production facilities and certain other properties. The Company has not capitalized future abandonment costs on a majority of its long-lived transportation and distribution assets because the Company does not have a legal obligation to restore the area surrounding abandoned assets. The fair value of retirement costs is estimated by Company personnel based on abandonment costs of similar properties available to field operations and depreciated over the life of the related assets. Revisions to estimates result from material changes in the expected timing or amount of cash flows associated with AROs. Income or expense resulting from the settlement of ARO liabilities is included in net gain (loss) from asset sales in the Consolidated Statements of Income. The ARO liability is adjusted to present value each period through an accretion calculation using a credit-adjusted risk-free interest rate. Changes in Questar's AROs from the Consolidated Balance Sheets were as follows:

	9 Months Ended
	September 30,
	2012			2011
	(in millions)
AROs at beginning of year	$	63.8		$	60.9
Accretion	2.3			2.3
Liabilities incurred	2.2			0.9
Revisions in estimated cash flows	(1.2		)	2.4
Liabilities settled	(0.8		)	(2.0		)
AROs at September 30,	$	66.3		$	64.5

Wexpro collects from Questar Gas and deposits in trust certain funds related to AROs. The funds are recorded as other noncurrent assets and used to satisfy retirement obligations as the properties are abandoned. The accounting treatment of reclamation activities associated with AROs for properties administered under the Wexpro Agreement is defined in a guideline letter between Wexpro and the Utah Division of Public Utilities and the Staff of the Public Service Commission of Wyoming (PSCW).