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Commitments And Contingencies (Tables)

6 Months Ended

Jun. 30, 2017

Commitments and Contingencies [Line Items]

Operating Expense Purchase Obligations

At June 30, 2017, minimum future commitments related to these operating expense purchase obligations were as follows (in millions):

	Alliant Energy				IPL				WPL
Purchased power (a)		$1,326				$1,231				$95
Natural gas	774				402				372
Coal (b)	140				66				74
Other (c)	30				28				2
		$2,270				$1,727				$543

(a) Includes payments required by purchased power agreements for capacity rights and minimum quantities of MWhs required to be purchased.

(b) Corporate Services entered into system-wide coal contracts on behalf of IPL and WPL that include minimum future commitments. These commitments were assigned to IPL and WPL based on information available as of June 30, 2017 regarding expected future usage, which is subject to change.

(c) Includes individual commitments incurred during the normal course of business that exceeded $1 million at June 30, 2017.

MGP Site Estimated Future Costs And Recorded Liabilities

At June 30, 2017, estimated future costs expected to be incurred for the investigation, remediation and monitoring of the MGP sites, as well as environmental liabilities recorded on the balance sheets for these sites, were as follows (in millions). At June 30, 2017, such amounts for WPL were not material.

	Alliant Energy						IPL
Range of estimated future costs		$12		-	$31			$10		-	$27
Current and non-current environmental liabilities	17						14

IPL [Member]

Commitments and Contingencies [Line Items]

Operating Expense Purchase Obligations

At June 30, 2017, minimum future commitments related to these operating expense purchase obligations were as follows (in millions):

	Alliant Energy				IPL				WPL
Purchased power (a)		$1,326				$1,231				$95
Natural gas	774				402				372
Coal (b)	140				66				74
Other (c)	30				28				2
		$2,270				$1,727				$543

(a) Includes payments required by purchased power agreements for capacity rights and minimum quantities of MWhs required to be purchased.

(b) Corporate Services entered into system-wide coal contracts on behalf of IPL and WPL that include minimum future commitments. These commitments were assigned to IPL and WPL based on information available as of June 30, 2017 regarding expected future usage, which is subject to change.

(c) Includes individual commitments incurred during the normal course of business that exceeded $1 million at June 30, 2017.

MGP Site Estimated Future Costs And Recorded Liabilities

At June 30, 2017, estimated future costs expected to be incurred for the investigation, remediation and monitoring of the MGP sites, as well as environmental liabilities recorded on the balance sheets for these sites, were as follows (in millions). At June 30, 2017, such amounts for WPL were not material.

	Alliant Energy						IPL
Range of estimated future costs		$12		-	$31			$10		-	$27
Current and non-current environmental liabilities	17						14

WPL [Member]

Commitments and Contingencies [Line Items]

Operating Expense Purchase Obligations

At June 30, 2017, minimum future commitments related to these operating expense purchase obligations were as follows (in millions):

	Alliant Energy				IPL				WPL
Purchased power (a)		$1,326				$1,231				$95
Natural gas	774				402				372
Coal (b)	140				66				74
Other (c)	30				28				2
		$2,270				$1,727				$543

(a) Includes payments required by purchased power agreements for capacity rights and minimum quantities of MWhs required to be purchased.

(b) Corporate Services entered into system-wide coal contracts on behalf of IPL and WPL that include minimum future commitments. These commitments were assigned to IPL and WPL based on information available as of June 30, 2017 regarding expected future usage, which is subject to change.

(c) Includes individual commitments incurred during the normal course of business that exceeded $1 million at June 30, 2017.

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+ References

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- Definition

Tabular disclosure of material liabilities for remediation, site restoration, postclosure, monitoring commitments, or other exit costs that may occur on the sale, disposal or abandonment of a property as a result of unanticipated contamination of the assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 5.Y.Q4)
-URI http://asc.fasb.org/extlink&oid=27011672&loc=d3e149879-122751

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