ASSET RETIREMENT OBLIGATIONS

12 Months Ended

Dec. 31, 2014

Asset Retirement Obligation Disclosure [Abstract]

ASSET RETIREMENT OBLIGATIONS

Asset Retirement Obligations

We have asset retirement obligations primarily related to asbestos abatement at certain generation facilities, office buildings, and service centers; dismantling wind generation projects; disposal of PCB-contaminated transformers; and closure of fly-ash landfills at certain generation facilities. We establish regulatory assets and liabilities to record the differences between ongoing expense recognition under the asset retirement obligation accounting rules and the ratemaking practices for retirement costs authorized by the applicable regulators. All asset retirement obligations are recorded as other long-term liabilities on our balance sheets.

The following table shows changes to our asset retirement obligations through December 31, 2014:

(Millions)
Asset retirement obligations at December 31, 2011	$	18.6
Accretion	1.0
Revisions to estimated cash flows	(2.5		)	(1)
Settlements	(0.4		)
Asset retirement obligations at December 31, 2012	16.7
Accretion	0.9
Revisions to estimated cash flows	0.5
Settlements	(0.1		)
Asset retirement obligations at December 31, 2013	18.0
Accretion	1.0
Revisions to estimated cash flows	1.5			(2)
Settlements	(0.2		)
Asset retirement obligations at December 31, 2014	$	20.3

⁽¹⁾  Revisions were made to estimated cash flows related to asset retirement obligations for the PCB-contaminated transformers primarily due to changes in estimated removal costs, estimated settlement date, and transformer quantities.

⁽²⁾  Revisions were made to estimated cash flows related to asset retirement obligations for the asbestos at electric generation facilities primarily due to changes in estimated settlement dates.