REGULATORY ASSETS AND LIABILITIES (Tables)

12 Months Ended

Dec. 31, 2011

REGULATORY ASSETS AND LIABILITIES

Schedule of regulatory assets and liabilities reflected in Integrys Energy Group's Balance Sheets

(Millions)	2011		2010		See Note
Regulatory assets
Unrecognized pension and other postretirement benefit costs	$	733.6	$	544.5	18
Environmental remediation costs (net of insurance recoveries) (1)	626.8		653.0		16
Merger and acquisition related pension and other postretirement benefit costs (2)	121.9		133.8
Derivatives	59.0		34.1		1	(h)
Asset retirement obligations	58.1		47.6		14
Income tax related items	37.9		28.1		15
Decoupling	33.3		50.5		26
De Pere Energy Center (3)	28.6		31.0
Unamortized loss on reacquired debt (4)	18.8		14.6		1	(n)
Conservation program costs (5)	13.3		15.3
Weston 3 lightning strike (6)	10.9		14.5
Other	41.4		46.0
Total	$	1,783.6	$	1,613.0
Balance Sheet Presentation
Current	$	125.1	$	117.9
Long-term	1,658.5		1,495.1
Total	$	1,783.6	$	1,613.0
Regulatory liabilities
Removal costs (7)	$	298.0	$	278.1
Energy costs refundable through rate adjustments (8)	30.4		51.8
Unrecognized pension and other postretirement benefit costs	18.4		20.0		18
Decoupling	17.2		8.1		26
Uncollectible expense	11.3		8.3		26
Derivatives	9.3		6.0		1	(h)
Energy Efficiency Program (5)	5.4		7.2
Other	10.0		12.4
Total	$	400.0	$	391.9
Balance Sheet Presentation
Current	$	67.5	$	75.7
Long-term	332.5		316.2
Total	$	400.0	$	391.9

(1)  As of December 31, 2011, we had not yet made cash expenditures for $615.1 million of these environmental remediation costs. The recovery of environmental remediation costs depends on the timing of the actual expenditures.

(2)  Composed of unrecognized benefit costs that existed prior to the PELLC merger and the MERC and MGU acquisitions.

(3)  Prior to WPS purchasing the De Pere Energy Center, WPS had a long-term power purchase contract with the De Pere Energy Center that was accounted for as a capital lease. As a result of the purchase, the capital lease obligation was reversed and the difference between the capital lease asset and the purchase price was recorded as a regulatory asset. WPS is authorized recovery of this regulatory asset through 2023.

(4)Amounts for PGL and NSG are recovered over the term of the replacement debt as authorized by the ICC. WPS is authorized recovery of this regulatory asset through 2015. UPPCO is authorized recovery of this regulatory asset through 2018.

(5)Represents amounts recoverable from and/or refundable to customers related to programs designed to meet energy efficiency standards. MERC is authorized recovery of this regulatory asset through 2012.

(6)In 2007, a lightning strike caused significant damage to the Weston 3 generating facility. The PSCW approved the deferral of the incremental fuel and purchased power expenses, as well as the non-fuel operating and maintenance expenditures incurred as a result of the outage that were not covered by insurance. WPS is authorized recovery of this regulatory asset through 2014.

(7)  Represents amounts collected from customers to cover the cost of future removal of property, plant, and equipment.

(8)  Represents the over-collection of energy costs from customers that will be refunded in the future.