Asset Retirement Obligations (Tables)

6 Months Ended

Jun. 30, 2011

Asset Retirement Obligations [Abstract]

Changes in ARO

Changes in Questar's ARO from the Consolidated Balance Sheets for the six months ended June 30 were as follows:

	2011	2010
	(in millions)
ARO liability at December 31	$60.9	$65.0
Accretion	1.5	1.4
Liabilities incurred	0.6	0.4
Revisions	2.4	(8.3)
Liabilities settled	(0.2)	(0.2)
ARO liability at June 30	$65.2	$58.3