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Asset Retirement Obligations | 9 Months Ended
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Sep. 30, 2024
Asset Retirement Obligation Disclosure [Abstract] |
Asset Retirement Obligations | Asset Retirement Obligations We have recognized Asset Retirement Obligations (AROs) related to our coal-fired generation plants, natural gas combustion turbines, solar facilities and wind turbines. The cost of AROs includes items such as site restoration, closure of ash pits and removal of certain structures, generators, asbestos and storage tanks. We have other legal obligations associated with the retirement of a variety of other long-lived tangible assets used in electric operations where the estimated settlement costs are individually and collectively immaterial. We have no assets legally restricted for the settlement of any AROs. As of September 30, 2024 and December 31, 2023, $0.1 million and $0.1 million, respectively, was included in other current liabilities and $38.8 million and $36.4 million, respectively, was included in other noncurrent liabilities in the consolidated balance sheets related to AROs. Coal Combustion Residual Regulations In May 2024, the Environmental Protection Agency (EPA) published a final rule amending coal combustion residual (CCR) regulations which introduces new requirements for the management of coal ash at active coal-fired power plants and inactive coal-fired power plants with a legacy surface impoundment. The regulations impose new requirements including groundwater monitoring, closure standards, post-closure care obligations, and potential remediation activities. As of September 30, 2024, we have not recognized an ARO for any liabilities which may be incurred because of the EPA’s final CCR rule as we cannot reasonably estimate the fair value of such a liability. We continue to review and assess the complex regulation to determine whether and to what extent, if any, our facilities will be impacted. Specifically, we are evaluating certain definitional matters within the regulation to determine the precise closure standards at an active facility. In addition, further site evaluations are necessary to determine the amount of coal ash stored on areas previously exempt from regulation, including areas of beneficial use. If it is determined that any of our facilities are impacted and new requirements are imposed by the regulation, we will recognize an ARO as soon as we are able to reasonably estimate the fair value of the liability.

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- Definition The entire disclosure for an asset retirement obligation and the associated long-lived asset. An asset retirement obligation is a legal obligation associated with the disposal or retirement from service of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 410 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481850/410-20-50-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 410 -SubTopic 20 -Name Accounting Standards Codification -Publisher FASB -URI https://asc.fasb.org/410-20/tableOfContent Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name Accounting Standards Codification -Section 50 -Paragraph 2 -SubTopic 20 -Topic 410 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481850/410-20-50-2 + Details
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