Asset Retirement Obligations

3 Months Ended

Mar. 31, 2015

Asset Retirement Obligation Disclosure [Abstract]

In the first quarter of 2015, an updated decommissioning study was completed for the Four Corners coal-fired plant, which resulted in an increase to the ARO in the amount of $18 million. The following schedule shows the change in our asset retirement obligations for the three months ended March 31, 2015 (dollars in millions):



Asset retirement obligations at January 1, 2015	$	391
Changes attributable to:
Accretion expense	6
Settlements	(7		)
Estimated cash flow revisions	18
Asset retirement obligations at March 31, 2015	$	408

Decommissioning activities for Four Corners Units 1-3 began in January 2014; thus, $29 million of the total asset retirement obligation of $408 million at March 31, 2015, is classified as a current liability on the balance sheet.

In accordance with regulatory accounting, APS accrues removal costs for its regulated utility assets, even if there is no legal obligation for removal. See detail of regulatory liabilities in Note 3.