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Commitments And Contingencies | 9 Months Ended
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Sep. 30, 2015
Commitments and Contingencies Disclosure | COMMITMENTS AND CONTINGENCIES (a) Capital Purchase Obligations - Various contractual obligations contain minimum future commitments related to capital expenditures for certain construction projects. IPL’s projects include generation maintenance and performance improvements for Marshalltown Combustion Turbine Units 1-3. WPL’s projects include the installation of a scrubber and baghouse at Edgewater Unit 5 to reduce SO2 and mercury emissions, generation maintenance and performance improvements at Columbia Units 1 and 2, and the installation of an SCR system at Columbia Unit 2 to reduce NOx emissions at the EGU. At September 30, 2015, Alliant Energy’s, IPL’s and WPL’s minimum future commitments related to certain contractual obligations for these projects were $27 million, $8 million and $19 million, respectively. (b) Operating Expense Purchase Obligations - Various commodity supply, transportation and storage contracts help meet obligations to provide electricity and natural gas to utility customers. Other operating expense purchase obligations with various vendors provide other goods and services. At September 30, 2015, minimum future commitments related to these operating expense purchase obligations were as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
Purchased power (a): |  |  |  |  |
DAEC (IPL) |  | $1,448 |  |  |  | $1,448 |  |  |  | $— |
Other | 183 |  |  | 1 |  |  | 182 |
| 1,631 |  |  | 1,449 |  |  | 182 |
Natural gas | 389 |  |  | 265 |  |  | 124 |
Coal (b) | 262 |  |  | 117 |  |  | 145 |
SO2 emission allowances | 22 |  |  | 22 |  |  | — |
Other (c) | 11 |  |  | 8 |  |  | 3 |
|  | $2,315 |  |  |  | $1,861 |  |  |  | $454 |
(a) | Includes payments required by PPAs 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 September 30, 2015 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 September 30, 2015.
(c) Legal Proceedings - Flood Damage Claims - In June 2013, several plaintiffs purporting to represent a class of residential and commercial property owners filed a complaint against CRANDIC, Alliant Energy and various other defendants in the Iowa District Court for Linn County. Plaintiffs assert claims of negligence and strict liability based on their allegations that CRANDIC (along with other defendants) caused or exacerbated flooding of the Cedar River in June 2008. In July 2013, the case was removed from state court to federal court based on federal jurisdiction. In September 2013, the U.S. District Court for the Northern District of Iowa dismissed the Plaintiffs’ claims and transferred the case for resolution to the Surface Transportation Board, the administrative agency that oversees the Interstate Commerce Commission Termination Act. In October 2013, the Plaintiffs appealed the federal court’s dismissal of the case to the Eighth Circuit Court of Appeals. In May 2015, the Eighth Circuit Court of Appeals vacated the U.S. District Court for the Northern District of Iowa’s decision and ordered the case remanded back to the Iowa District Court for Linn County. Alliant Energy and CRANDIC believe the case is without merit and will continue to vigorously contest the case. As a result, Alliant Energy does not currently believe any material losses from these claims are both probable and reasonably estimated, and therefore, has not recognized any material loss contingency amounts for this complaint as of September 30, 2015. Due to the lack of specific damages identified and the procedural nature of the activity to date, Alliant Energy is currently unable to provide an estimate of potential loss or range of potential loss. (d) Guarantees and Indemnifications - RMT - In 2013, Alliant Energy sold RMT. RMT provided renewable energy services, including construction and high voltage connection services for wind and solar projects. As part of the sale, Alliant Energy indemnified the buyer for any claims, including claims of warranty under the project obligations that were commenced or are based on actions that occurred prior to the sale, except for liabilities already accounted for through adjustments to the purchase price. The indemnification obligations either cease to exist when the statute of limitation for such claims is met or, in the case of RMT’s projects, when the warranty period under the agreements expires. The contractual warranty periods for RMT’s projects generally range from 12 to 60 months with the latest expiring in 2016. Limited warranties may be extended in certain cases for warranty work performed. Alliant Energy also continues to guarantee RMT’s performance obligations related to certain of RMT’s projects that were commenced prior to Alliant Energy’s sale of RMT. As of September 30, 2015, Alliant Energy had $123 million of performance guarantees outstanding, with $48 million and $75 million currently expected to expire in 2016 and 2017, respectively. The expiration of these performance guarantees may be extended depending on when all valid warranty claims are resolved for the respective projects. Although Alliant Energy has received warranty claims related to certain of these projects, it does not currently believe that material losses are both probable and reasonably estimated, and therefore, has not recognized any material liabilities related to these matters as of September 30, 2015. Alliant Energy does not currently believe that the range of future potential loss from any warranty claims will be material. Refer to Note 16 for further discussion of RMT, including amounts Alliant Energy recorded to “Operating expenses” during the nine months ended September 30, 2015 and 2014 related to certain warranty claims. Whiting Petroleum - In 2004, Alliant Energy sold its remaining interest in Whiting Petroleum. Whiting Petroleum is an independent oil and gas company. Alliant Energy continues to guarantee the obligations related to the abandonment of certain platforms off the coast of California and related onshore plant and equipment that were owned by Whiting Petroleum prior to Alliant Energy’s sale of Whiting Petroleum. The guarantee does not include a maximum limit. As of September 30, 2015, the present value of the abandonment obligations is estimated at $27 million. Alliant Energy believes that no payments will be made under this guarantee. Alliant Energy has not recognized any material liabilities related to this guarantee as of September 30, 2015. IPL’s Minnesota Electric Distribution Assets - IPL provided indemnifications associated with the July 2015 sale of its Minnesota electric distribution assets for losses resulting from potential breach of IPL’s representations, warranties and obligations under the sale agreement. Alliant Energy and IPL believe the likelihood of having to make any material cash payments under these indemnifications is remote. IPL has not recorded any material liabilities related to these indemnifications as of September 30, 2015. The general terms of the indemnifications provided by IPL included a maximum limit of $17 million and expire in October 2020. Refer to Note 3 for further discussion of the sale of IPL’s Minnesota electric distribution assets. (e) Environmental Matters - MGP Sites - IPL and WPL have current or previous ownership interests in various sites that are previously associated with the production of gas for which IPL and WPL have, or may have in the future, liability for investigation, remediation and monitoring costs. IPL and WPL are working pursuant to the requirements of various federal and state agencies to investigate, mitigate, prevent and remediate, where necessary, the environmental impacts to property, including natural resources, at and around these former MGP sites in order to protect public health and the environment. IPL and WPL are currently monitoring and/or remediating 24 and 5 sites, respectively. No longer included in IPL’s sites is a Minnesota site for which responsibility of the site was transferred to the buyer as part of the sale of IPL’s Minnesota natural gas distribution assets completed in April 2015. Environmental liabilities related to the MGP sites are recorded based upon periodic studies. Such amounts are based on the best current estimate of the remaining amount to be incurred for investigation, remediation and monitoring costs for those sites where the investigation process has been or is substantially completed, and the minimum of the estimated cost range for those sites where the investigation is in its earlier stages. There are inherent uncertainties associated with the estimated remaining costs for MGP projects primarily due to unknown site conditions and potential changes in regulatory agency requirements. It is possible that future cost estimates will be greater than current estimates as the investigation process proceeds and as additional facts become known. The amounts recognized as liabilities are reduced for expenditures incurred and are adjusted as further information develops or circumstances change. Costs of future expenditures for environmental remediation obligations are not discounted. At September 30, 2015, 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):
| Alliant Energy |  | IPL |  | WPL
Range of estimated future costs |  | $11 |  | - | $29 |  |  | $10 |  | - | $26 |  |  | $1 |  | - | $3
Current and non-current environmental liabilities | 16 |  | 13 |  | 3
WPL Consent Decree - In 2009, the EPA sent a notice of violation to WPL as an owner and the operator of Edgewater, Nelson Dewey and Columbia alleging that the owners of such EGUs failed to comply with appropriate pre-construction review and permitting requirements and as a result violated the Prevention of Significant Deterioration program requirements, Title V Operating Permit requirements of the CAA and the Wisconsin State Implementation Plan. In 2010, the Sierra Club filed complaints against WPL, as owner and operator of Nelson Dewey and Columbia, and separately as owner and operator of Edgewater, based on allegations that modifications were made at the facilities without complying with the Prevention of Significant Deterioration program requirements, Title V Operating Permit requirements of the CAA and state regulatory counterparts contained within the Wisconsin State Implementation Plan designed to implement the CAA. In April 2013, WPL, along with the other owners of Edgewater and Columbia, entered into a Consent Decree with the EPA and the Sierra Club to resolve the claims relating to Edgewater, Columbia and Nelson Dewey, while admitting no liability. In June 2013, the Consent Decree was approved by the U.S. District Court for the Western District of Wisconsin, thereby resolving all claims against WPL. Under the Consent Decree, WPL is required to install the following emission controls systems:
• | SCR system at Edgewater Unit 5 by May 1, 2013 (placed in service in 2012);
• | Scrubbers and baghouses at Columbia Units 1 and 2 by December 31, 2014 (placed in service in 2014);
• | Scrubber and baghouse at Edgewater Unit 5 by December 31, 2016; and
• | SCR system at Columbia Unit 2 by December 31, 2018.
WPL is also required to fuel switch or retire Nelson Dewey Units 1 and 2 and Edgewater Unit 3 by December 31, 2015, and Edgewater Unit 4 by December 31, 2018. In addition, the Consent Decree establishes emission rate limits for SO2, NOx and particulate matter for Columbia Units 1 and 2, Nelson Dewey Units 1 and 2 and Edgewater Units 4 and 5. The Consent Decree also includes annual plant-wide emission caps for SO2 and NOx for Columbia, Edgewater and Nelson Dewey. In addition, WPL will complete approximately $7 million in environmental mitigation projects. Final recovery of the costs expected to be incurred related to the Consent Decree will be decided by the PSCW in future rate cases or other proceedings. Alliant Energy and WPL currently expect to recover any material costs incurred by WPL related to compliance with the terms of the Consent Decree from WPL’s electric customers. IPL Consent Decree - In July 2015, IPL entered into a Consent Decree with the EPA, the Sierra Club, the State of Iowa and Linn County in Iowa to resolve potential claims regarding CAA issues associated with emissions from IPL’s coal-fired generating facilities in Iowa, while admitting no liability. In September 2015, the Consent Decree was approved by the U.S. District Court for the Northern District of Iowa, thereby resolving all potential claims against IPL. Under the Consent Decree, IPL is required to install the following emission controls systems:
• | Scrubber and baghouse at the Ottumwa Generating Station by December 31, 2015 (placed in service in 2014);
• | Scrubber and baghouse at the Lansing Generating Station by December 31, 2016 (scrubber was placed in service in June 2015 and baghouse was placed in service in 2010); and
• | SCR system or equivalent NOx reduction system at the Ottumwa Generating Station by December 31, 2019.
IPL is also required to fuel switch or retire the following EGUs:
• | M.L. Kapp Generating Station by August 31, 2015 (switched the fuel type from coal to natural gas in June 2015);
• | Prairie Creek Unit 4 by June 1, 2018;
• | Burlington Generating Station by December 31, 2021; and
• | Prairie Creek Units 1 and 3 by December 31, 2025.
In addition, IPL is required to either install combined cycle technology at, or retire, the Dubuque and Sutherland Generation Stations by June 1, 2019. IPL previously switched the fuel type from coal to natural gas at these EGUs. The Consent Decree also establishes SO2, NOx and particulate matter emission rate limits with varying averaging times for the Burlington, Lansing, M.L. Kapp, Ottumwa and Prairie Creek Generating Stations. In addition, the Consent Decree includes calendar-year SO2 and NOx emission caps for the Prairie Creek Generating Station, and calendar-year SO2 and NOx emission caps in aggregate for the Burlington, Dubuque, Lansing, M.L. Kapp, Ottumwa, Prairie Creek and Sutherland Generating Stations. Pursuant to the Consent Decree, IPL paid a civil penalty of $1 million in September 2015 and will complete approximately $6 million in environmental mitigation projects. Alliant Energy and IPL currently expect to recover costs incurred by IPL related to the emission control systems and environmental mitigation projects from IPL’s electric customers. The recovery of such costs will be decided by IPL’s regulators in future rate cases or other proceedings. Alliant Energy and IPL currently do not expect to recover costs related to the civil penalty from IPL’s electric customers. Other Environmental Contingencies - In addition to the environmental liabilities discussed above, various environmental rules are monitored that may have a significant impact on future operations. Several of these environmental rules are subject to legal challenges, reconsideration and/or other uncertainties. Given uncertainties regarding the outcome, timing and compliance plans for these environmental matters, the complete financial impact of each of these rules is not able to be determined; however future capital investments and/or modifications to EGUs to comply with certain of these rules could be significant. Specific current, proposed or potential environmental matters include, among others: Cross-State Air Pollution Rule, Clean Air Visibility Rule, Mercury and Air Toxic Standard Rule, Industrial Boiler and Process Heater Maximum Achievable Control Technology Rule, Ozone NAAQS Rule, SO2 NAAQS Rule, Federal Clean Water Act including Section 316(b), Effluent Limitation Guidelines, Hydroelectric Fish Passage Device, CCR Rule, and various legislation and EPA regulations to monitor and regulate the emission of greenhouse gases, including carbon emissions from new (CAA Section 111(b)) and existing (CAA Section 111(d)) fossil-fueled EGUs. Some recent developments concerning these environmental matters are included below: Air Quality - Ozone NAAQS Rule - In October 2015, the EPA published a final revised Ozone NAAQS Rule, which is more stringent than the previous version of the rule and may require NOx emission reductions in certain non-attainment areas designated by the EPA. The EPA’s final designations of non-attainment areas for this revised rule are currently expected to be issued by October 2017. Compliance deadlines range from 2020 through 2037 depending on the level of NOx emissions in non-attainment areas. Clean Air Act Section 111(d) - In October 2015, the EPA published final standards under Section 111(d) of the CAA, which establish guidelines for states to follow in developing plans to reduce carbon dioxide emissions from existing fossil-fueled EGUs. The final standards include an interim compliance period from 2022 through 2029 and a final compliance requirement beginning in 2030. The EPA also published a proposed federal plan that would be implemented in states that do not complete a fully approved state plan. Clean Air Act Section 111(b) - In October 2015, the EPA published final standards under Section 111(b) of the CAA, which establish carbon dioxide emissions limits for certain new fossil-fueled EGUs. Marshalltown and WPL’s proposed Riverside expansion are expected to be impacted by these standards. Marshalltown is being constructed, and WPL’s proposed Riverside expansion is being designed, to achieve compliance with these standards. Water Quality - Effluent Limitation Guidelines - In November 2015, the EPA published final effluent limitation guidelines, which require changes to discharge limits for wastewater from steam generating facilities. Compliance will be required after November 1, 2018 but before December 31, 2023, depending on each facility’s wastewater permit renewal cycle for existing steam generating facilities and immediately upon operation for new steam generating facilities constructed after the effective date of the final guidelines. Land and Solid Waste - CCR Rule - Refer to Note 10 for discussion of the final CCR Rule, including additional AROs that were recognized during the nine months ended September 30, 2015 related to such rule.
IPL [Member] |
Commitments and Contingencies Disclosure | COMMITMENTS AND CONTINGENCIES (a) Capital Purchase Obligations - Various contractual obligations contain minimum future commitments related to capital expenditures for certain construction projects. IPL’s projects include generation maintenance and performance improvements for Marshalltown Combustion Turbine Units 1-3. WPL’s projects include the installation of a scrubber and baghouse at Edgewater Unit 5 to reduce SO2 and mercury emissions, generation maintenance and performance improvements at Columbia Units 1 and 2, and the installation of an SCR system at Columbia Unit 2 to reduce NOx emissions at the EGU. At September 30, 2015, Alliant Energy’s, IPL’s and WPL’s minimum future commitments related to certain contractual obligations for these projects were $27 million, $8 million and $19 million, respectively. (b) Operating Expense Purchase Obligations - Various commodity supply, transportation and storage contracts help meet obligations to provide electricity and natural gas to utility customers. Other operating expense purchase obligations with various vendors provide other goods and services. At September 30, 2015, minimum future commitments related to these operating expense purchase obligations were as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
Purchased power (a): |  |  |  |  |
DAEC (IPL) |  | $1,448 |  |  |  | $1,448 |  |  |  | $— |
Other | 183 |  |  | 1 |  |  | 182 |
| 1,631 |  |  | 1,449 |  |  | 182 |
Natural gas | 389 |  |  | 265 |  |  | 124 |
Coal (b) | 262 |  |  | 117 |  |  | 145 |
SO2 emission allowances | 22 |  |  | 22 |  |  | — |
Other (c) | 11 |  |  | 8 |  |  | 3 |
|  | $2,315 |  |  |  | $1,861 |  |  |  | $454 |
(a) | Includes payments required by PPAs 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 September 30, 2015 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 September 30, 2015.
(c) Legal Proceedings - Flood Damage Claims - In June 2013, several plaintiffs purporting to represent a class of residential and commercial property owners filed a complaint against CRANDIC, Alliant Energy and various other defendants in the Iowa District Court for Linn County. Plaintiffs assert claims of negligence and strict liability based on their allegations that CRANDIC (along with other defendants) caused or exacerbated flooding of the Cedar River in June 2008. In July 2013, the case was removed from state court to federal court based on federal jurisdiction. In September 2013, the U.S. District Court for the Northern District of Iowa dismissed the Plaintiffs’ claims and transferred the case for resolution to the Surface Transportation Board, the administrative agency that oversees the Interstate Commerce Commission Termination Act. In October 2013, the Plaintiffs appealed the federal court’s dismissal of the case to the Eighth Circuit Court of Appeals. In May 2015, the Eighth Circuit Court of Appeals vacated the U.S. District Court for the Northern District of Iowa’s decision and ordered the case remanded back to the Iowa District Court for Linn County. Alliant Energy and CRANDIC believe the case is without merit and will continue to vigorously contest the case. As a result, Alliant Energy does not currently believe any material losses from these claims are both probable and reasonably estimated, and therefore, has not recognized any material loss contingency amounts for this complaint as of September 30, 2015. Due to the lack of specific damages identified and the procedural nature of the activity to date, Alliant Energy is currently unable to provide an estimate of potential loss or range of potential loss. (d) Guarantees and Indemnifications - RMT - In 2013, Alliant Energy sold RMT. RMT provided renewable energy services, including construction and high voltage connection services for wind and solar projects. As part of the sale, Alliant Energy indemnified the buyer for any claims, including claims of warranty under the project obligations that were commenced or are based on actions that occurred prior to the sale, except for liabilities already accounted for through adjustments to the purchase price. The indemnification obligations either cease to exist when the statute of limitation for such claims is met or, in the case of RMT’s projects, when the warranty period under the agreements expires. The contractual warranty periods for RMT’s projects generally range from 12 to 60 months with the latest expiring in 2016. Limited warranties may be extended in certain cases for warranty work performed. Alliant Energy also continues to guarantee RMT’s performance obligations related to certain of RMT’s projects that were commenced prior to Alliant Energy’s sale of RMT. As of September 30, 2015, Alliant Energy had $123 million of performance guarantees outstanding, with $48 million and $75 million currently expected to expire in 2016 and 2017, respectively. The expiration of these performance guarantees may be extended depending on when all valid warranty claims are resolved for the respective projects. Although Alliant Energy has received warranty claims related to certain of these projects, it does not currently believe that material losses are both probable and reasonably estimated, and therefore, has not recognized any material liabilities related to these matters as of September 30, 2015. Alliant Energy does not currently believe that the range of future potential loss from any warranty claims will be material. Refer to Note 16 for further discussion of RMT, including amounts Alliant Energy recorded to “Operating expenses” during the nine months ended September 30, 2015 and 2014 related to certain warranty claims. Whiting Petroleum - In 2004, Alliant Energy sold its remaining interest in Whiting Petroleum. Whiting Petroleum is an independent oil and gas company. Alliant Energy continues to guarantee the obligations related to the abandonment of certain platforms off the coast of California and related onshore plant and equipment that were owned by Whiting Petroleum prior to Alliant Energy’s sale of Whiting Petroleum. The guarantee does not include a maximum limit. As of September 30, 2015, the present value of the abandonment obligations is estimated at $27 million. Alliant Energy believes that no payments will be made under this guarantee. Alliant Energy has not recognized any material liabilities related to this guarantee as of September 30, 2015. IPL’s Minnesota Electric Distribution Assets - IPL provided indemnifications associated with the July 2015 sale of its Minnesota electric distribution assets for losses resulting from potential breach of IPL’s representations, warranties and obligations under the sale agreement. Alliant Energy and IPL believe the likelihood of having to make any material cash payments under these indemnifications is remote. IPL has not recorded any material liabilities related to these indemnifications as of September 30, 2015. The general terms of the indemnifications provided by IPL included a maximum limit of $17 million and expire in October 2020. Refer to Note 3 for further discussion of the sale of IPL’s Minnesota electric distribution assets. (e) Environmental Matters - MGP Sites - IPL and WPL have current or previous ownership interests in various sites that are previously associated with the production of gas for which IPL and WPL have, or may have in the future, liability for investigation, remediation and monitoring costs. IPL and WPL are working pursuant to the requirements of various federal and state agencies to investigate, mitigate, prevent and remediate, where necessary, the environmental impacts to property, including natural resources, at and around these former MGP sites in order to protect public health and the environment. IPL and WPL are currently monitoring and/or remediating 24 and 5 sites, respectively. No longer included in IPL’s sites is a Minnesota site for which responsibility of the site was transferred to the buyer as part of the sale of IPL’s Minnesota natural gas distribution assets completed in April 2015. Environmental liabilities related to the MGP sites are recorded based upon periodic studies. Such amounts are based on the best current estimate of the remaining amount to be incurred for investigation, remediation and monitoring costs for those sites where the investigation process has been or is substantially completed, and the minimum of the estimated cost range for those sites where the investigation is in its earlier stages. There are inherent uncertainties associated with the estimated remaining costs for MGP projects primarily due to unknown site conditions and potential changes in regulatory agency requirements. It is possible that future cost estimates will be greater than current estimates as the investigation process proceeds and as additional facts become known. The amounts recognized as liabilities are reduced for expenditures incurred and are adjusted as further information develops or circumstances change. Costs of future expenditures for environmental remediation obligations are not discounted. At September 30, 2015, 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):
| Alliant Energy |  | IPL |  | WPL
Range of estimated future costs |  | $11 |  | - | $29 |  |  | $10 |  | - | $26 |  |  | $1 |  | - | $3
Current and non-current environmental liabilities | 16 |  | 13 |  | 3
WPL Consent Decree - In 2009, the EPA sent a notice of violation to WPL as an owner and the operator of Edgewater, Nelson Dewey and Columbia alleging that the owners of such EGUs failed to comply with appropriate pre-construction review and permitting requirements and as a result violated the Prevention of Significant Deterioration program requirements, Title V Operating Permit requirements of the CAA and the Wisconsin State Implementation Plan. In 2010, the Sierra Club filed complaints against WPL, as owner and operator of Nelson Dewey and Columbia, and separately as owner and operator of Edgewater, based on allegations that modifications were made at the facilities without complying with the Prevention of Significant Deterioration program requirements, Title V Operating Permit requirements of the CAA and state regulatory counterparts contained within the Wisconsin State Implementation Plan designed to implement the CAA. In April 2013, WPL, along with the other owners of Edgewater and Columbia, entered into a Consent Decree with the EPA and the Sierra Club to resolve the claims relating to Edgewater, Columbia and Nelson Dewey, while admitting no liability. In June 2013, the Consent Decree was approved by the U.S. District Court for the Western District of Wisconsin, thereby resolving all claims against WPL. Under the Consent Decree, WPL is required to install the following emission controls systems:
• | SCR system at Edgewater Unit 5 by May 1, 2013 (placed in service in 2012);
• | Scrubbers and baghouses at Columbia Units 1 and 2 by December 31, 2014 (placed in service in 2014);
• | Scrubber and baghouse at Edgewater Unit 5 by December 31, 2016; and
• | SCR system at Columbia Unit 2 by December 31, 2018.
WPL is also required to fuel switch or retire Nelson Dewey Units 1 and 2 and Edgewater Unit 3 by December 31, 2015, and Edgewater Unit 4 by December 31, 2018. In addition, the Consent Decree establishes emission rate limits for SO2, NOx and particulate matter for Columbia Units 1 and 2, Nelson Dewey Units 1 and 2 and Edgewater Units 4 and 5. The Consent Decree also includes annual plant-wide emission caps for SO2 and NOx for Columbia, Edgewater and Nelson Dewey. In addition, WPL will complete approximately $7 million in environmental mitigation projects. Final recovery of the costs expected to be incurred related to the Consent Decree will be decided by the PSCW in future rate cases or other proceedings. Alliant Energy and WPL currently expect to recover any material costs incurred by WPL related to compliance with the terms of the Consent Decree from WPL’s electric customers. IPL Consent Decree - In July 2015, IPL entered into a Consent Decree with the EPA, the Sierra Club, the State of Iowa and Linn County in Iowa to resolve potential claims regarding CAA issues associated with emissions from IPL’s coal-fired generating facilities in Iowa, while admitting no liability. In September 2015, the Consent Decree was approved by the U.S. District Court for the Northern District of Iowa, thereby resolving all potential claims against IPL. Under the Consent Decree, IPL is required to install the following emission controls systems:
• | Scrubber and baghouse at the Ottumwa Generating Station by December 31, 2015 (placed in service in 2014);
• | Scrubber and baghouse at the Lansing Generating Station by December 31, 2016 (scrubber was placed in service in June 2015 and baghouse was placed in service in 2010); and
• | SCR system or equivalent NOx reduction system at the Ottumwa Generating Station by December 31, 2019.
IPL is also required to fuel switch or retire the following EGUs:
• | M.L. Kapp Generating Station by August 31, 2015 (switched the fuel type from coal to natural gas in June 2015);
• | Prairie Creek Unit 4 by June 1, 2018;
• | Burlington Generating Station by December 31, 2021; and
• | Prairie Creek Units 1 and 3 by December 31, 2025.
In addition, IPL is required to either install combined cycle technology at, or retire, the Dubuque and Sutherland Generation Stations by June 1, 2019. IPL previously switched the fuel type from coal to natural gas at these EGUs. The Consent Decree also establishes SO2, NOx and particulate matter emission rate limits with varying averaging times for the Burlington, Lansing, M.L. Kapp, Ottumwa and Prairie Creek Generating Stations. In addition, the Consent Decree includes calendar-year SO2 and NOx emission caps for the Prairie Creek Generating Station, and calendar-year SO2 and NOx emission caps in aggregate for the Burlington, Dubuque, Lansing, M.L. Kapp, Ottumwa, Prairie Creek and Sutherland Generating Stations. Pursuant to the Consent Decree, IPL paid a civil penalty of $1 million in September 2015 and will complete approximately $6 million in environmental mitigation projects. Alliant Energy and IPL currently expect to recover costs incurred by IPL related to the emission control systems and environmental mitigation projects from IPL’s electric customers. The recovery of such costs will be decided by IPL’s regulators in future rate cases or other proceedings. Alliant Energy and IPL currently do not expect to recover costs related to the civil penalty from IPL’s electric customers. Other Environmental Contingencies - In addition to the environmental liabilities discussed above, various environmental rules are monitored that may have a significant impact on future operations. Several of these environmental rules are subject to legal challenges, reconsideration and/or other uncertainties. Given uncertainties regarding the outcome, timing and compliance plans for these environmental matters, the complete financial impact of each of these rules is not able to be determined; however future capital investments and/or modifications to EGUs to comply with certain of these rules could be significant. Specific current, proposed or potential environmental matters include, among others: Cross-State Air Pollution Rule, Clean Air Visibility Rule, Mercury and Air Toxic Standard Rule, Industrial Boiler and Process Heater Maximum Achievable Control Technology Rule, Ozone NAAQS Rule, SO2 NAAQS Rule, Federal Clean Water Act including Section 316(b), Effluent Limitation Guidelines, Hydroelectric Fish Passage Device, CCR Rule, and various legislation and EPA regulations to monitor and regulate the emission of greenhouse gases, including carbon emissions from new (CAA Section 111(b)) and existing (CAA Section 111(d)) fossil-fueled EGUs. Some recent developments concerning these environmental matters are included below: Air Quality - Ozone NAAQS Rule - In October 2015, the EPA published a final revised Ozone NAAQS Rule, which is more stringent than the previous version of the rule and may require NOx emission reductions in certain non-attainment areas designated by the EPA. The EPA’s final designations of non-attainment areas for this revised rule are currently expected to be issued by October 2017. Compliance deadlines range from 2020 through 2037 depending on the level of NOx emissions in non-attainment areas. Clean Air Act Section 111(d) - In October 2015, the EPA published final standards under Section 111(d) of the CAA, which establish guidelines for states to follow in developing plans to reduce carbon dioxide emissions from existing fossil-fueled EGUs. The final standards include an interim compliance period from 2022 through 2029 and a final compliance requirement beginning in 2030. The EPA also published a proposed federal plan that would be implemented in states that do not complete a fully approved state plan. Clean Air Act Section 111(b) - In October 2015, the EPA published final standards under Section 111(b) of the CAA, which establish carbon dioxide emissions limits for certain new fossil-fueled EGUs. Marshalltown and WPL’s proposed Riverside expansion are expected to be impacted by these standards. Marshalltown is being constructed, and WPL’s proposed Riverside expansion is being designed, to achieve compliance with these standards. Water Quality - Effluent Limitation Guidelines - In November 2015, the EPA published final effluent limitation guidelines, which require changes to discharge limits for wastewater from steam generating facilities. Compliance will be required after November 1, 2018 but before December 31, 2023, depending on each facility’s wastewater permit renewal cycle for existing steam generating facilities and immediately upon operation for new steam generating facilities constructed after the effective date of the final guidelines. Land and Solid Waste - CCR Rule - Refer to Note 10 for discussion of the final CCR Rule, including additional AROs that were recognized during the nine months ended September 30, 2015 related to such rule.
WPL [Member] |
Commitments and Contingencies Disclosure | COMMITMENTS AND CONTINGENCIES (a) Capital Purchase Obligations - Various contractual obligations contain minimum future commitments related to capital expenditures for certain construction projects. IPL’s projects include generation maintenance and performance improvements for Marshalltown Combustion Turbine Units 1-3. WPL’s projects include the installation of a scrubber and baghouse at Edgewater Unit 5 to reduce SO2 and mercury emissions, generation maintenance and performance improvements at Columbia Units 1 and 2, and the installation of an SCR system at Columbia Unit 2 to reduce NOx emissions at the EGU. At September 30, 2015, Alliant Energy’s, IPL’s and WPL’s minimum future commitments related to certain contractual obligations for these projects were $27 million, $8 million and $19 million, respectively. (b) Operating Expense Purchase Obligations - Various commodity supply, transportation and storage contracts help meet obligations to provide electricity and natural gas to utility customers. Other operating expense purchase obligations with various vendors provide other goods and services. At September 30, 2015, minimum future commitments related to these operating expense purchase obligations were as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
Purchased power (a): |  |  |  |  |
DAEC (IPL) |  | $1,448 |  |  |  | $1,448 |  |  |  | $— |
Other | 183 |  |  | 1 |  |  | 182 |
| 1,631 |  |  | 1,449 |  |  | 182 |
Natural gas | 389 |  |  | 265 |  |  | 124 |
Coal (b) | 262 |  |  | 117 |  |  | 145 |
SO2 emission allowances | 22 |  |  | 22 |  |  | — |
Other (c) | 11 |  |  | 8 |  |  | 3 |
|  | $2,315 |  |  |  | $1,861 |  |  |  | $454 |
(a) | Includes payments required by PPAs 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 September 30, 2015 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 September 30, 2015.
(c) Legal Proceedings - Flood Damage Claims - In June 2013, several plaintiffs purporting to represent a class of residential and commercial property owners filed a complaint against CRANDIC, Alliant Energy and various other defendants in the Iowa District Court for Linn County. Plaintiffs assert claims of negligence and strict liability based on their allegations that CRANDIC (along with other defendants) caused or exacerbated flooding of the Cedar River in June 2008. In July 2013, the case was removed from state court to federal court based on federal jurisdiction. In September 2013, the U.S. District Court for the Northern District of Iowa dismissed the Plaintiffs’ claims and transferred the case for resolution to the Surface Transportation Board, the administrative agency that oversees the Interstate Commerce Commission Termination Act. In October 2013, the Plaintiffs appealed the federal court’s dismissal of the case to the Eighth Circuit Court of Appeals. In May 2015, the Eighth Circuit Court of Appeals vacated the U.S. District Court for the Northern District of Iowa’s decision and ordered the case remanded back to the Iowa District Court for Linn County. Alliant Energy and CRANDIC believe the case is without merit and will continue to vigorously contest the case. As a result, Alliant Energy does not currently believe any material losses from these claims are both probable and reasonably estimated, and therefore, has not recognized any material loss contingency amounts for this complaint as of September 30, 2015. Due to the lack of specific damages identified and the procedural nature of the activity to date, Alliant Energy is currently unable to provide an estimate of potential loss or range of potential loss. (d) Guarantees and Indemnifications - RMT - In 2013, Alliant Energy sold RMT. RMT provided renewable energy services, including construction and high voltage connection services for wind and solar projects. As part of the sale, Alliant Energy indemnified the buyer for any claims, including claims of warranty under the project obligations that were commenced or are based on actions that occurred prior to the sale, except for liabilities already accounted for through adjustments to the purchase price. The indemnification obligations either cease to exist when the statute of limitation for such claims is met or, in the case of RMT’s projects, when the warranty period under the agreements expires. The contractual warranty periods for RMT’s projects generally range from 12 to 60 months with the latest expiring in 2016. Limited warranties may be extended in certain cases for warranty work performed. Alliant Energy also continues to guarantee RMT’s performance obligations related to certain of RMT’s projects that were commenced prior to Alliant Energy’s sale of RMT. As of September 30, 2015, Alliant Energy had $123 million of performance guarantees outstanding, with $48 million and $75 million currently expected to expire in 2016 and 2017, respectively. The expiration of these performance guarantees may be extended depending on when all valid warranty claims are resolved for the respective projects. Although Alliant Energy has received warranty claims related to certain of these projects, it does not currently believe that material losses are both probable and reasonably estimated, and therefore, has not recognized any material liabilities related to these matters as of September 30, 2015. Alliant Energy does not currently believe that the range of future potential loss from any warranty claims will be material. Refer to Note 16 for further discussion of RMT, including amounts Alliant Energy recorded to “Operating expenses” during the nine months ended September 30, 2015 and 2014 related to certain warranty claims. Whiting Petroleum - In 2004, Alliant Energy sold its remaining interest in Whiting Petroleum. Whiting Petroleum is an independent oil and gas company. Alliant Energy continues to guarantee the obligations related to the abandonment of certain platforms off the coast of California and related onshore plant and equipment that were owned by Whiting Petroleum prior to Alliant Energy’s sale of Whiting Petroleum. The guarantee does not include a maximum limit. As of September 30, 2015, the present value of the abandonment obligations is estimated at $27 million. Alliant Energy believes that no payments will be made under this guarantee. Alliant Energy has not recognized any material liabilities related to this guarantee as of September 30, 2015. IPL’s Minnesota Electric Distribution Assets - IPL provided indemnifications associated with the July 2015 sale of its Minnesota electric distribution assets for losses resulting from potential breach of IPL’s representations, warranties and obligations under the sale agreement. Alliant Energy and IPL believe the likelihood of having to make any material cash payments under these indemnifications is remote. IPL has not recorded any material liabilities related to these indemnifications as of September 30, 2015. The general terms of the indemnifications provided by IPL included a maximum limit of $17 million and expire in October 2020. Refer to Note 3 for further discussion of the sale of IPL’s Minnesota electric distribution assets. (e) Environmental Matters - MGP Sites - IPL and WPL have current or previous ownership interests in various sites that are previously associated with the production of gas for which IPL and WPL have, or may have in the future, liability for investigation, remediation and monitoring costs. IPL and WPL are working pursuant to the requirements of various federal and state agencies to investigate, mitigate, prevent and remediate, where necessary, the environmental impacts to property, including natural resources, at and around these former MGP sites in order to protect public health and the environment. IPL and WPL are currently monitoring and/or remediating 24 and 5 sites, respectively. No longer included in IPL’s sites is a Minnesota site for which responsibility of the site was transferred to the buyer as part of the sale of IPL’s Minnesota natural gas distribution assets completed in April 2015. Environmental liabilities related to the MGP sites are recorded based upon periodic studies. Such amounts are based on the best current estimate of the remaining amount to be incurred for investigation, remediation and monitoring costs for those sites where the investigation process has been or is substantially completed, and the minimum of the estimated cost range for those sites where the investigation is in its earlier stages. There are inherent uncertainties associated with the estimated remaining costs for MGP projects primarily due to unknown site conditions and potential changes in regulatory agency requirements. It is possible that future cost estimates will be greater than current estimates as the investigation process proceeds and as additional facts become known. The amounts recognized as liabilities are reduced for expenditures incurred and are adjusted as further information develops or circumstances change. Costs of future expenditures for environmental remediation obligations are not discounted. At September 30, 2015, 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):
| Alliant Energy |  | IPL |  | WPL
Range of estimated future costs |  | $11 |  | - | $29 |  |  | $10 |  | - | $26 |  |  | $1 |  | - | $3
Current and non-current environmental liabilities | 16 |  | 13 |  | 3
WPL Consent Decree - In 2009, the EPA sent a notice of violation to WPL as an owner and the operator of Edgewater, Nelson Dewey and Columbia alleging that the owners of such EGUs failed to comply with appropriate pre-construction review and permitting requirements and as a result violated the Prevention of Significant Deterioration program requirements, Title V Operating Permit requirements of the CAA and the Wisconsin State Implementation Plan. In 2010, the Sierra Club filed complaints against WPL, as owner and operator of Nelson Dewey and Columbia, and separately as owner and operator of Edgewater, based on allegations that modifications were made at the facilities without complying with the Prevention of Significant Deterioration program requirements, Title V Operating Permit requirements of the CAA and state regulatory counterparts contained within the Wisconsin State Implementation Plan designed to implement the CAA. In April 2013, WPL, along with the other owners of Edgewater and Columbia, entered into a Consent Decree with the EPA and the Sierra Club to resolve the claims relating to Edgewater, Columbia and Nelson Dewey, while admitting no liability. In June 2013, the Consent Decree was approved by the U.S. District Court for the Western District of Wisconsin, thereby resolving all claims against WPL. Under the Consent Decree, WPL is required to install the following emission controls systems:
• | SCR system at Edgewater Unit 5 by May 1, 2013 (placed in service in 2012);
• | Scrubbers and baghouses at Columbia Units 1 and 2 by December 31, 2014 (placed in service in 2014);
• | Scrubber and baghouse at Edgewater Unit 5 by December 31, 2016; and
• | SCR system at Columbia Unit 2 by December 31, 2018.
WPL is also required to fuel switch or retire Nelson Dewey Units 1 and 2 and Edgewater Unit 3 by December 31, 2015, and Edgewater Unit 4 by December 31, 2018. In addition, the Consent Decree establishes emission rate limits for SO2, NOx and particulate matter for Columbia Units 1 and 2, Nelson Dewey Units 1 and 2 and Edgewater Units 4 and 5. The Consent Decree also includes annual plant-wide emission caps for SO2 and NOx for Columbia, Edgewater and Nelson Dewey. In addition, WPL will complete approximately $7 million in environmental mitigation projects. Final recovery of the costs expected to be incurred related to the Consent Decree will be decided by the PSCW in future rate cases or other proceedings. Alliant Energy and WPL currently expect to recover any material costs incurred by WPL related to compliance with the terms of the Consent Decree from WPL’s electric customers. IPL Consent Decree - In July 2015, IPL entered into a Consent Decree with the EPA, the Sierra Club, the State of Iowa and Linn County in Iowa to resolve potential claims regarding CAA issues associated with emissions from IPL’s coal-fired generating facilities in Iowa, while admitting no liability. In September 2015, the Consent Decree was approved by the U.S. District Court for the Northern District of Iowa, thereby resolving all potential claims against IPL. Under the Consent Decree, IPL is required to install the following emission controls systems:
• | Scrubber and baghouse at the Ottumwa Generating Station by December 31, 2015 (placed in service in 2014);
• | Scrubber and baghouse at the Lansing Generating Station by December 31, 2016 (scrubber was placed in service in June 2015 and baghouse was placed in service in 2010); and
• | SCR system or equivalent NOx reduction system at the Ottumwa Generating Station by December 31, 2019.
IPL is also required to fuel switch or retire the following EGUs:
• | M.L. Kapp Generating Station by August 31, 2015 (switched the fuel type from coal to natural gas in June 2015);
• | Prairie Creek Unit 4 by June 1, 2018;
• | Burlington Generating Station by December 31, 2021; and
• | Prairie Creek Units 1 and 3 by December 31, 2025.
In addition, IPL is required to either install combined cycle technology at, or retire, the Dubuque and Sutherland Generation Stations by June 1, 2019. IPL previously switched the fuel type from coal to natural gas at these EGUs. The Consent Decree also establishes SO2, NOx and particulate matter emission rate limits with varying averaging times for the Burlington, Lansing, M.L. Kapp, Ottumwa and Prairie Creek Generating Stations. In addition, the Consent Decree includes calendar-year SO2 and NOx emission caps for the Prairie Creek Generating Station, and calendar-year SO2 and NOx emission caps in aggregate for the Burlington, Dubuque, Lansing, M.L. Kapp, Ottumwa, Prairie Creek and Sutherland Generating Stations. Pursuant to the Consent Decree, IPL paid a civil penalty of $1 million in September 2015 and will complete approximately $6 million in environmental mitigation projects. Alliant Energy and IPL currently expect to recover costs incurred by IPL related to the emission control systems and environmental mitigation projects from IPL’s electric customers. The recovery of such costs will be decided by IPL’s regulators in future rate cases or other proceedings. Alliant Energy and IPL currently do not expect to recover costs related to the civil penalty from IPL’s electric customers. Other Environmental Contingencies - In addition to the environmental liabilities discussed above, various environmental rules are monitored that may have a significant impact on future operations. Several of these environmental rules are subject to legal challenges, reconsideration and/or other uncertainties. Given uncertainties regarding the outcome, timing and compliance plans for these environmental matters, the complete financial impact of each of these rules is not able to be determined; however future capital investments and/or modifications to EGUs to comply with certain of these rules could be significant. Specific current, proposed or potential environmental matters include, among others: Cross-State Air Pollution Rule, Clean Air Visibility Rule, Mercury and Air Toxic Standard Rule, Industrial Boiler and Process Heater Maximum Achievable Control Technology Rule, Ozone NAAQS Rule, SO2 NAAQS Rule, Federal Clean Water Act including Section 316(b), Effluent Limitation Guidelines, Hydroelectric Fish Passage Device, CCR Rule, and various legislation and EPA regulations to monitor and regulate the emission of greenhouse gases, including carbon emissions from new (CAA Section 111(b)) and existing (CAA Section 111(d)) fossil-fueled EGUs. Some recent developments concerning these environmental matters are included below: Air Quality - Ozone NAAQS Rule - In October 2015, the EPA published a final revised Ozone NAAQS Rule, which is more stringent than the previous version of the rule and may require NOx emission reductions in certain non-attainment areas designated by the EPA. The EPA’s final designations of non-attainment areas for this revised rule are currently expected to be issued by October 2017. Compliance deadlines range from 2020 through 2037 depending on the level of NOx emissions in non-attainment areas. Clean Air Act Section 111(d) - In October 2015, the EPA published final standards under Section 111(d) of the CAA, which establish guidelines for states to follow in developing plans to reduce carbon dioxide emissions from existing fossil-fueled EGUs. The final standards include an interim compliance period from 2022 through 2029 and a final compliance requirement beginning in 2030. The EPA also published a proposed federal plan that would be implemented in states that do not complete a fully approved state plan. Clean Air Act Section 111(b) - In October 2015, the EPA published final standards under Section 111(b) of the CAA, which establish carbon dioxide emissions limits for certain new fossil-fueled EGUs. Marshalltown and WPL’s proposed Riverside expansion are expected to be impacted by these standards. Marshalltown is being constructed, and WPL’s proposed Riverside expansion is being designed, to achieve compliance with these standards. Water Quality - Effluent Limitation Guidelines - In November 2015, the EPA published final effluent limitation guidelines, which require changes to discharge limits for wastewater from steam generating facilities. Compliance will be required after November 1, 2018 but before December 31, 2023, depending on each facility’s wastewater permit renewal cycle for existing steam generating facilities and immediately upon operation for new steam generating facilities constructed after the effective date of the final guidelines. Land and Solid Waste - CCR Rule - Refer to Note 10 for discussion of the final CCR Rule, including additional AROs that were recognized during the nine months ended September 30, 2015 related to such rule.

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