The Duke Energy Registrants are subject to federal, state and local regulations regarding air and water quality, hazardous and solid waste disposal, coal ash and other environmental matters. These regulations can be changed from time to time, imposing new obligations on the Duke Energy Registrants. The following environmental matters impact all Duke Energy Registrants.

In addition to AROs recorded as a result of various environmental regulations, the Duke Energy Registrants are responsible for environmental remediation at various sites. These include certain properties that are part of ongoing operations and sites formerly owned or used by Duke Energy entities. These sites are in various stages of investigation, remediation and monitoring. Managed in conjunction with relevant federal, state and local agencies, remediation activities vary based upon site conditions and location, remediation requirements, complexity and sharing of responsibility. If remediation activities involve joint and several liability provisions, strict liability, or cost recovery or contribution actions, the Duke Energy Registrants could potentially be held responsible for environmental impacts caused by other potentially responsible parties and may also benefit from insurance policies or contractual indemnities that cover some or all cleanup costs. Liabilities are recorded when losses become probable and are reasonably estimable. The total costs that may be incurred cannot be estimated because the extent of environmental impact, allocation among potentially responsible parties, remediation alternatives and/or regulatory decisions have not yet been determined at all sites. Additional costs associated with remediation activities are likely to be incurred in the future and could be significant. Costs are typically expensed as Operation, maintenance and other on the Condensed Consolidated Statements of Operations unless regulatory recovery of the costs is deemed probable.

Duke Energy and several Duke Energy renewables project companies have been named in multiple lawsuits arising out of Texas Storm Uri in mid-February 2021, and particularly, in the deregulated market managed by the Electric Reliability Council of Texas. There are 30 state court actions pending. These lawsuits seek recovery for property damages, personal injury and for wrongful death allegedly incurred by the plaintiffs as a result of power outages, which the plaintiffs claim was the result of the defendants' failures. The cases pending in state court have been consolidated into a Texas state court multidistrict litigation proceeding before a single judge to handle all pretrial coordination. Duke Energy cannot predict the outcomes of these matters.

In March 2017, Duke Energy Carolinas and Duke Energy Progress filed a civil action in the North Carolina Business Court against various insurance providers. The lawsuit seeks payment for coal ash related liabilities covered by third-party liability insurance policies. The insurance policies were issued between 1971 and 1986 and provide third-party liability insurance for property damage. The civil action seeks damages for breach of contract and indemnification for costs arising from the Coal Ash Act and the U.S. Environmental Protection Agency CCR rule at 15 coal-fired plants in North Carolina and South Carolina.

Duke Energy Carolinas and Duke Energy Progress have resolved claims against all, but two of the insurers, sued in this litigation and are dismissing their claims against the settling insurers. Duke Energy Carolinas and Duke Energy Progress have received approximately $418 million of coal ash insurance litigation proceeds from settlements with insurer-defendants and these proceeds will be distributed in accordance with the terms of the CCR settlement agreement. The companies are assessing their options with regard to the two remaining foreign insurers that have defaulted. Duke Energy Carolinas and Duke Energy Progress cannot predict the outcome of this matter.

On June 16, 2021, a group of nine individuals went over a low head dam adjacent to the Dan River Steam Station in Eden, North Carolina, while water tubing. Emergency personnel rescued four people and five others were confirmed deceased. On August 11, 2021, Duke Energy Carolinas was served with the complaint filed in Durham County Superior Court on behalf of four survivors, which was later amended to include all the decedents along with the survivors. The lawsuit alleges that Duke Energy Carolinas knew that the river was used for recreational purposes and that Duke Energy did not adequately warn about the dam. On September 30, 2021, Duke Energy Carolinas filed its Motion to Dismiss and Motion for Transfer of Venue from Durham County to Rockingham County. A hearing on these motions is set for November 15, 2021, and discovery has commenced. Duke Energy Carolinas cannot predict the outcome of this matter.

In November 2017, Duke Energy Carolinas entered into a standard FERC large generator interconnection agreement (LGIA) with NTE Carolinas II, LLC (NTE), a company that proposed to build a combined-cycle natural gas plant in Rockingham County, North Carolina. On September 6, 2019, Duke Energy Carolinas filed a lawsuit in Mecklenburg County Superior Court against NTE for breach of contract, alleging that NTE's failure to pay benchmark payments for Duke Energy Carolinas' transmission system upgrades required under the interconnection agreement constituted a termination of the interconnection agreement. Duke Energy Carolinas is seeking a monetary judgment against NTE because NTE failed to make multiple milestone payments. The lawsuit was moved to federal court in North Carolina. NTE filed a motion to dismiss Duke Energy Carolinas’ complaint and brought counterclaims alleging anti-competitive conduct and violations of state and federal statutes. Duke Energy Carolinas filed a motion to dismiss NTE's counterclaims.

On May 21, 2020, in response to a NTE petition challenging Duke Energy Carolinas' termination of the LGIA, FERC issued a ruling that 1) it has exclusive jurisdiction to determine whether a transmission provider may terminate a LGIA; 2) FERC approval is required to terminate a conforming LGIA if objected to by the interconnection customer; and 3) Duke Energy may not announce the termination of a conforming LGIA unless FERC has approved the termination. FERC's Office of Enforcement also initiated an investigation of Duke Energy Carolinas into matters pertaining to the LGIA. Duke Energy Carolinas is cooperating with the Office of Enforcement but cannot predict the outcome of this investigation.

Duke Energy Carolinas has experienced numerous claims for indemnification and medical cost reimbursement related to asbestos exposure. These claims relate to damages for bodily injuries alleged to have arisen from exposure to or use of asbestos in connection with construction and maintenance activities conducted on its electric generation plants prior to 1985. As of September 30, 2021, there were 74 asserted claims for non-malignant cases with cumulative relief sought of up to $15 million, and 58 asserted claims for malignant cases with cumulative relief sought of up to $21 million. Based on Duke Energy Carolinas’ experience, it is expected that the ultimate resolution of most of these claims likely will be less than the amount claimed.

Duke Energy Carolinas has recognized asbestos-related reserves of $508 million at September 30, 2021, and $572 million at December 31, 2020. These reserves are classified in Other within Other Noncurrent Liabilities and Other within Current Liabilities on the Condensed Consolidated Balance Sheets. These reserves are based upon Duke Energy Carolinas' best estimate for current and future asbestos claims through 2041 and are recorded on an undiscounted basis. In light of the uncertainties inherent in a longer-term forecast, management does not believe they can reasonably estimate the indemnity and medical costs that might be incurred after 2041 related to such potential claims. It is possible Duke Energy Carolinas may incur asbestos liabilities in excess of the recorded reserves.

Duke Energy Carolinas has third-party insurance to cover certain losses related to asbestos-related injuries and damages above an aggregate self-insured retention. Duke Energy Carolinas’ cumulative payments began to exceed the self-insured retention in 2008. Future payments up to the policy limit will be reimbursed by the third-party insurance carrier. The insurance policy limit for potential future insurance recoveries indemnification and medical cost claim payments is $697 million in excess of the self-insured retention. Receivables for insurance recoveries were $644 million at September 30, 2021, and $704 million at December 31, 2020. These amounts are classified in Other within Other Noncurrent Assets and Receivables within Current Assets on the Condensed Consolidated Balance Sheets. Duke Energy Carolinas is not aware of any uncertainties regarding the legal sufficiency of insurance claims. Duke Energy Carolinas believes the insurance recovery asset is probable of recovery as the insurance carrier continues to have a strong financial strength rating.

As described in Note 1, Duke Energy adopted the new guidance for credit losses effective January 1, 2020, using the modified retrospective method of adoption, which does not require restatement of prior year reported results. The reserve for credit losses for insurance receivables based on adoption of the new standard is $15 million for Duke Energy and Duke Energy Carolinas as of September 30, 2021, and December 31, 2020. The insurance receivable is evaluated based on the risk of default and the historical losses, current conditions and expected conditions around collectability. Management evaluates the risk of default annually based on payment history, credit rating and changes in the risk of default from credit agencies.

On June 18, 2018, Duke Energy Progress and Duke Energy Florida sued the U.S. in the U.S. Court of Federal Claims for damages incurred for the period 2014 through 2018. The lawsuit claimed the Department of Energy breached a contract in failing to accept spent nuclear fuel under the Nuclear Waste Policy Act of 1982 and asserted damages for the cost of on-site storage in the amount of $100 million and $200 million for Duke Energy Progress and Duke Energy Florida, respectively. Discovery is now complete, and trial is anticipated to be scheduled in 2022. Duke Energy Progress and Duke Energy Florida cannot predict the outcome of this matter.

Duke Energy Florida, on behalf of its customers, entered into a PPA for the purchase of firm capacity and energy from a qualifying facility under the Public Utilities Regulatory Policies Act of 1978. Duke Energy Florida determined the qualifying facility did not perform in accordance with the PPA, and Duke Energy Florida terminated the PPA. The qualifying facility counterparty filed a confidential American Arbitration Association (AAA) arbitration demand, challenging the termination of the PPA and seeking damages.

The final arbitration hearing occurred during the week of December 7, 2020. An interim arbitral award was issued in March 2021, upholding Duke Energy Florida's positions on all issues and awarding the company termination costs. In May 2021, the final arbitral award was issued awarding Duke Energy Florida its claimed fees and costs. On August 18, 2021, Duke Energy Florida filed a motion in Florida state court to confirm the arbitral award.

On January 27, 2020, Hoosier Environmental Council (HEC) filed a Petition for Administrative Review with the Indiana Office of Environmental Adjudication challenging the Indiana Department of Environmental Management’s (IDEM's) December 10, 2019, partial approval of Duke Energy Indiana’s ash pond closure plan. After hearing oral arguments in early April 2021 on Duke Energy Indiana's and HEC's competing Motions for Summary Judgment, on May 4, 2021, the administrative court rejected all of HEC’s claims and issued a ruling in favor of Duke Energy Indiana. On June 3, 2021, HEC filed an appeal in Superior Court to seek judicial review of the order. On June 25, 2021, Duke Energy Indiana filed its response to the Petition to Review. On August 30, 2021, HEC served Duke Energy Indiana with its Brief in Support of Petition for Judicial Review. On October 29, 2021, Duke Energy Indiana and IDEM filed their response briefs. HEC's Reply Brief is due on or before November 22, 2021. Oral argument will be heard in December 2021, in Marion County Superior Court. Duke Energy Indiana cannot predict the outcome of this matter.

The Duke Energy Registrants are involved in other legal, tax and regulatory proceedings arising in the ordinary course of business, some of which involve significant amounts. The Duke Energy Registrants believe the final disposition of these proceedings will not have a material effect on their results of operations, cash flows or financial position. Reserves are classified on the Condensed Consolidated Balance Sheets in Other within Other Noncurrent Liabilities and Other within Current Liabilities.

As part of their normal business, the Duke Energy Registrants are party to various financial guarantees, performance guarantees and other contractual commitments to extend guarantees of credit and other assistance to various subsidiaries, investees and other third parties. These guarantees involve elements of performance and credit risk, which are not fully recognized on the Condensed Consolidated Balance Sheets and have uncapped maximum potential payments. However, the Duke Energy Registrants do not believe these guarantees will have a material effect on their results of operations, cash flows or financial position.

In addition, the Duke Energy Registrants enter into various fixed-price, noncancelable commitments to purchase or sell power or natural gas, take-or-pay arrangements, transportation, or throughput agreements and other contracts that may or may not be recognized on their respective Condensed Consolidated Balance Sheets. Some of these arrangements may be recognized at fair value on their respective Condensed Consolidated Balance Sheets if such contracts meet the definition of a derivative and the NPNS exception does not apply. In most cases, the Duke Energy Registrants’ purchase obligation contracts contain provisions for price adjustments, minimum purchase levels and other financial commitments.