COMMITMENTS, GUARANTEES AND CONTINGENCIES	6 Months Ended
Jun. 30, 2025
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS, GUARANTEES AND CONTINGENCIES	COMMITMENTS, GUARANTEES AND CONTINGENCIES Power Purchase and Sale Agreements. Our long-term PPAs have been evaluated under the accounting guidance for variable interest entities. We have determined that either we have no variable interest in the PPAs or, where we do have variable interests, we are not the primary beneficiary; therefore, consolidation is not required. These conclusions are based on the fact that we do not have both control over activities that are most significant to the entity and an obligation to absorb losses or receive benefits from the entity’s performance. Our financial exposure relating to these PPAs is limited to our capacity and energy payments. Our PPAs are summarized in Note 9. Commitments, Guarantees and Contingencies to the Consolidated Financial Statements in our 2024 Form 10-K, with additional disclosure provided in the following paragraphs. Square Butte PPA. As of June 30, 2025, Square Butte had total debt outstanding of $157.6 million. Fuel expenses are recoverable through Minnesota Power’s fuel adjustment clause and include the cost of coal purchased from BNI Energy under a long-term contract. Minnesota Power’s cost of power purchased from Square Butte during the six months ended June 30, 2025, was $40.9 million ($44.2 million for the same period in 2024). This reflects Minnesota Power’s pro rata share of total Square Butte costs based on the 50 percent output entitlement. Included in this amount was Minnesota Power’s pro rata share of interest expense of $2.1 million ($2.6 million for the same period in 2024). Minnesota Power’s payments to Square Butte are approved as a purchased power expense for ratemaking purposes by both the MPUC and the FERC. Minnkota Power PSA. Minnesota Power has a PSA with Minnkota Power, which commenced in 2014. Under the PSA, Minnesota Power is selling a portion of its entitlement from Square Butte to Minnkota Power, resulting in Minnkota Power’s net entitlement increasing and Minnesota Power’s net entitlement decreasing until Minnesota Power’s share is eliminated at the end of 2025. Of Minnesota Power’s 50 percent output entitlement, Minnesota Power sold to Minnkota Power approximately 46 percent in 2025 and 41 percent in 2024. Coal, Rail and Shipping Contracts. Minnesota Power has coal supply agreements providing for the purchase of a significant portion of its coal requirements through December 2027. Minnesota Power also has coal transportation agreements in place for the delivery of a significant portion of its coal requirements through December 2027. The costs of fuel and related transportation costs for Minnesota Power’s generation are recoverable from Minnesota Power’s utility customers through the fuel adjustment clause. Environmental Matters. Our businesses are subject to regulation of environmental matters by various federal, state, and local authorities. A number of regulatory changes to the Clean Air Act, the Clean Water Act and various waste management requirements have been promulgated by both the EPA and state authorities over the past several years. Minnesota Power’s facilities are subject to additional requirements under many of these regulations. Minnesota Power is reshaping its generation portfolio, over time, to reduce its reliance on coal, has installed cost-effective emission control technology, and advocates for sound science and policy during rulemaking implementation. We consider our businesses to be in substantial compliance with currently applicable environmental regulations and believe all necessary permits have been obtained. We anticipate that with many state and federal environmental regulations and requirements finalized, or to be finalized in the near future, potential expenditures for future environmental matters may be material and require significant capital investments. Minnesota Power has evaluated various environmental compliance scenarios using possible outcomes of environmental regulations to project power supply trends and impacts on customers. We review environmental matters on a quarterly basis. Accruals for environmental matters are recorded when it is probable that a liability has been incurred and the amount of the liability can be reasonably estimated based on current law and existing technologies. Accruals are adjusted as assessment and remediation efforts progress, or as additional technical or legal information becomes available. Accruals for environmental liabilities are included in the Consolidated Balance Sheet at undiscounted amounts and exclude claims for recoveries from insurance or other third parties. Costs related to environmental contamination treatment and cleanup are expensed unless recoverable in rates from customers. Federal Environmental Regulatory Agenda. On March 12, 2025, the EPA announced its intent to reevaluate or reconsider numerous environmental regulations. This list includes various air, water, and waste environmental regulatory actions, many of which apply at the Company. The specific timing or outcome of this initiative is not yet known, but regular required rulemaking processes and procedures still apply, and litigation may also occur. The following disclosures do not attempt to discern potential impacts of these deregulatory actions until and unless formal rulemaking or other regulatory actions are announced and the potential impacts to ALLETE operations can be discerned. We are unable to predict the outcome of the reevaluation or reconsideration of these environmental regulations. Air. The electric utility industry is regulated both at the federal and state level to address air emissions. Minnesota Power’s thermal generating facilities mainly burn low-sulfur western sub-bituminous coal, as well as natural gas and biomass. All of Minnesota Power’s coal-fired generating facilities are equipped with pollution control equipment such as scrubbers, baghouses and low NOX technologies. Under currently applicable environmental regulations, these facilities are substantially compliant with emission requirements. Cross-State Air Pollution Rule (CSAPR). The CSAPR requires certain states in the eastern half of the U.S., including Minnesota, to reduce power plant emissions that contribute to ozone or fine particulate pollution in other states. The CSAPR does not require installation of controls but does require facilities have sufficient allowances to cover their emissions on an annual basis. These allowances are allocated to facilities from each state’s annual budget and can be bought and sold. Based on our review of the NOX and SO2 allowances issued and pending issuance as well as consideration of current rules, we currently expect generation levels and emission rates will result in continued compliance with the CSAPR. Minnesota Power will continue to monitor ongoing CSAPR rulemakings and compliance implementation, including the EPA’s Good Neighbor Rule which modifies certain aspects of the CSAPR’s program scope and extent (see EPA Good Neighbor Plan for 2015 Ozone NAAQS). National Ambient Air Quality Standards (NAAQS). The EPA is required to review each NAAQS every five years. If the EPA determines that a state’s air quality is not in compliance with the NAAQS, the state is required to adopt plans describing how it will reduce emissions to attain the NAAQS. Minnesota Power actively monitors NAAQS developments, and the EPA has recently reassessed several primary and secondary NAAQS for NOx, SO2, and particulate matter. Implementation of the EPA’s February 2024 final rule lowering the annual primary standard for fine particulate matter began on May 6, 2024. On December 27, 2024, the EPA published a final rule in the Federal Register revising the secondary SO2 NAAQS while retaining the NOX and particulate matter secondary standards, with a final rule effective date of January 27, 2025. Anticipated timelines and compliance costs related to this and other potential NAAQS revisions cannot yet be estimated but costs could be material. Minnesota Power would seek recovery of additional costs through a rate proceeding. NOTE 6. COMMITMENTS, GUARANTEES AND CONTINGENCIES (Continued) Environmental Matters (Continued) EPA Good Neighbor Plan for 2015 Ozone NAAQS. On June 5, 2023, after disapproving state implementation plans, the EPA published a final Federal Implementation Plan (FIP) rule in the Federal Register, the Good Neighbor Plan, to address regional ozone transport for the 2015 Ozone NAAQS by reducing NOX emissions during the period of May 1 through September 30 (ozone season). In its justification for the final rule, the EPA asserted that 23 states, including Minnesota, were modeled as significant contributors to downwind states’ challenges in attaining or maintaining ozone NAAQS compliance within their state borders. The Good Neighbor Plan is designed to resolve this interstate transport issue by implementing a variety of NOX reduction strategies, including federal implementation plan requirements, NOX emission limitations, and ozone season allowance program requirements. The final rule imposed restrictions on fossil-fuel fired power plants in 22 states and on certain industrial sources in 20 states, with implementation occurring through changes to the existing CSAPR program for power plants. Since the EPA partially disapproved the Good Neighbor State Implementation Plans (SIPs) for the states of Minnesota and Wisconsin, among others, Minnesota became subject to the final Good Neighbor Plan. However, Minnesota Power and a coalition of other Minnesota utilities and industry (the parties) co-filed challenges to the EPA’s final Minnesota SIP disapproval, submitting a petition for reconsideration and stay to the EPA, and a petition for judicial review to the Eighth Circuit Court. The parties are challenging and requesting reconsideration of certain technical components of the EPA’s review and subsequent partial disapproval of the state of Minnesota’s SIP. In July 2023, the Eighth Circuit Court granted a stay of the SIP disapproval preventing the Good Neighbor Plan from taking effect in Minnesota; oral arguments occurred in October 2024. In April 2024, the EPA published a partial denial of several administrative reconsideration and stay petitions, including from the Minnesota coalition. On September 29, 2023, the EPA issued an updated final interim rule addressing the stays in Minnesota and five other states, formally delaying the effective date of the final FIP for states with active stays in place. The state of Minnesota therefore did not become subject to compliance obligations for the 2023, 2024, or 2025 ozone seasons. Future compliance obligations will depend on resolution of the stay and outcomes of related litigation. Additional challenges have been filed against the final FIP rule by the Minnesota coalition parties and other entities, although the Minnesota coalition FIP challenge is currently in abeyance pending resolution of the SIP disapproval case. On June 27, 2024, the U.S. Supreme Court granted an emergency stay of the FIP rule requested by several states and industry groups, staying enforcement pending the D.C. Circuit’s review and any petition for writ of certiorari. In response to the U.S. Supreme Court’s stay order, the EPA published a third interim rule in the Federal Register on November 6, 2024, staying the effectiveness of the Good Neighbor FIP in the 10 remaining covered states, including Wisconsin. On March 10, 2025, the EPA filed a motion with the D.C. Circuit requesting a voluntary remand of its FIP, stating they anticipate completing replacement rulemaking by Fall 2026, and on March 12, 2025, the EPA also listed the Good Neighbor Plan reconsideration among its announcement of 31 proposed actions to reconsider EPA rules. Anticipated timelines and compliance costs related to final Good Neighbor Plan compliance cannot yet be estimated due to uncertainties about SIP approval resolution, implementation timing, FIP rule outcome, and allowance costs and facility emissions during the ozone season. However, the costs could be material, including costs of additional NOx controls, emission allowance program participation, or operational changes, if any are required. Minnesota Power would seek recovery of additional costs through a rate proceeding. Additionally, final rates in Minnesota Power’s most recent rate case were implemented on March 1, 2025, allowing any necessary allowance purchase costs to transfer to the fuel adjustment clause. EPA National Emission Standards for Hazardous Air Pollutants for Major Sources: Industrial, Commercial and Institutional Boilers and Process Heaters (Industrial Boiler MACT) Rule. A final rule issued by the EPA for Industrial Boiler MACT became effective in 2013 with compliance required at major existing sources in 2016, which applied to Minnesota Power’s Hibbard Renewable Energy Center and Rapids Energy Center. Compliance consisted largely of adjustments to fuels and operating practices and compliance costs were not material. After this initial rulemaking, litigation from 2016 through 2018 resulted in court orders directing that the EPA reconsider certain aspects of the regulation. A final rule incorporating these revisions became effective in December 2022, with a compliance deadline of October 6, 2025. Compliance costs are not expected to be material. NOTE 6. COMMITMENTS, GUARANTEES AND CONTINGENCIES (Continued) Environmental Matters (Continued) EPA Mercury and Air Toxics Standards (MATS) Rule. On May 7, 2024, the EPA promulgated a final rule to revise the existing 2012 MATS Rule, which regulates air emissions of hazardous air pollutants from coal- and oil-fired electric generating units (EGUs). The final rule eliminates certain MATS compliance flexibility, lowers the particulate emission standard for all coal-fired EGUs, and reduces the mercury emission standard for lignite-fired EGUs. The rule became effective July 8, 2024, with compliance required beginning July 6, 2027. The MATS regulation applies at Minnesota Power’s Boswell facility, which is currently well-controlled for these emissions and already complying with some of the new requirements. The Company anticipates the new rule will not have material impacts at Boswell. However, compliance costs cannot yet be fully estimated, and recovery of any additional costs would be sought through a rate proceeding. Litigation against the EPA’s latest MATS rule revision from a number of U.S. states, as well as several companies and industry groups, is ongoing. Motions to stay the rule were denied by the U.S. Court of Appeals for the D.C. Circuit on August 6, 2024, and the U.S. Supreme Court on October 4, 2024. On April 8, 2025, President Trump issued a proclamation entitled Regulatory Relief for Certain Stationary Sources to Further Promote American Energy granting a two-year compliance extension deadline to “certain stationary sources” subject to the 2024 MATS Rule. The list of the specific facilities who may qualify for the exemption has not yet been made available. On April 8, 2025, President Trump issued a proclamation entitled Regulatory Relief for Certain Stationary Sources to Further Promote American Energy. Pursuant to this proclamation, a two-year compliance extension deadline was granted on April 14, 2025 to 47 specific listed sources subject to the 2024 MATS rule, exempting those sources from compliance obligations of the 2024 rule until July 8, 2029; another proclamation was subsequently issued for several additional sources on July 17, 2025. Minnesota Power did not request a deadline extension. Subsequently, the EPA published a proposed rule on June 17, 2025, repealing the majority of the 2024 final MATS rule. The Company anticipates this proposed rule will not have material impact at Boswell. Climate Change. The scientific community generally accepts that emissions of GHGs are linked to global climate change which creates physical and financial risks. Physical risks could include but are not limited to: increased or decreased precipitation and water levels in lakes and rivers; increased or other changes in temperatures; increased risk of wildfires; and changes in the intensity and frequency of extreme weather events. These all have the potential to affect the Company’s business and operations. We are addressing climate change by taking the following steps that also ensure reliable and environmentally compliant generation resources to meet our customers’ requirements: •Expanding renewable power supply for both our operations and the operations of others; •Providing energy conservation initiatives for our customers and engaging in other demand side management efforts; •Improving efficiency of our generating facilities; •Supporting research of technologies to reduce carbon emissions from generating facilities and carbon sequestration efforts; •Evaluating and developing less carbon intensive future generating assets such as efficient and flexible natural gas‑fired generating facilities; •Managing vegetation on right-of-way corridors to reduce potential wildfire or storm damage risks; and •Practicing sound forestry management in our service territories to create landscapes more resilient to disruption from climate-related changes, including planting and managing long-lived conifer species. EPA Regulation of GHG Emissions. On April 25, 2024, the EPA issued several final greenhouse gas regulations to establish emissions standards and guidelines for fossil fuel-fired electric generating units (EGUs) under Section 111 of the Clean Air Act (CAA). The final rules revise new source performance standards (NSPS) for new, modified and reconstructed EGUs (Section 111(b) of the CAA) and creates new emission guidelines for existing EGUs (Section 111(d) of the CAA). The action also officially repeals the predecessor regulation “Affordable Clean Energy Rule”, first issued in 2019 and later vacated in 2021. Compliance will be required beginning January 1, 2030, for existing sources, and upon commencing operation of new units. The 111(d) rule also requires states to submit plans to provide for the establishment, implementation and enforcement of performance standards for existing sources. States must submit either a state plan or negative declaration letter to the EPA by May 11, 2026. NOTE 6. COMMITMENTS, GUARANTEES AND CONTINGENCIES (Continued) Environmental Matters (Continued) The final Section 111 rules apply to several Company assets, including existing EGUs at the Boswell and Laskin facilities as well as the proposed combined cycle natural gas-fired generating facility, Nemadji Trail Energy Center. The Company anticipates compliance with the rules may require operational or planning adjustments. The state implementation plan process for Section 111(d) existing units will also be a factor in determining specific requirements and timing. We are unable to predict compliance costs at this time; however, the costs could be material. Minnesota Power would seek recovery of additional costs through a rate proceeding. The Company is also monitoring endangerment finding evaluations by the EPA, as well as litigation of the final Section 111 rules. Litigation began when the rules were published in the Federal Register on May 9, 2024, and continues in federal court. Both the D.C. Circuit and the U.S. Supreme Court have declined requests to block the rule from becoming effective while litigation is ongoing. Oral arguments in the D.C. Circuit occurred on December 6, 2024, with a merits decision expected in mid-2025; however, currently the case remains in continued abeyance at the EPA’s request while the EPA reconsiders the Section 111 regulations. The EPA has stated it anticipates issuing a final reconsideration rule by December 2025. On June 17, 2025, the EPA published a proposed rule titled Repeal of Greenhouse Gas Emissions Standards for Fossil Fuel-Fired Electric Generating Units (reconsideration rule) that, if finalized, would repeal either all or certain aspects of the 2024 Section 111 rules. Outcomes from ongoing litigation over the 2024 Section 111 rules, the outcome of the proposed reconsideration rule, and the effects of future litigation will determine the timing of rule effectiveness and the ultimate compliance obligations required by the rule. The EPA also released a proposed rule on July 29, 2025 titled Reconsideration of 2009 Greenhouse Gas Endangerment Finding and Greenhouse Gas Standards seeking to repeal all greenhouse gas emissions standards for vehicles and engines as well as to rescind the EPA’s 2009 endangerment finding related to greenhouse gases. The Company cannot predict the outcome of this rulemaking initiative at this point, but resolution of this matter also has the potential to affect federal greenhouse gas regulations at stationary sources such as power plants. Water. The Clean Water Act requires NPDES permits be obtained from the EPA or delegated state agencies for any wastewater discharged into navigable waters. We have obtained all necessary NPDES permits, including NPDES storm water permits for applicable facilities, to conduct our operations. Steam Electric Power Generating Effluent Limitations Guidelines. In 2015, the EPA issued revised federal effluent limitation guidelines (ELG) for steam electric power generating stations under the Clean Water Act. It set effluent limits and prescribed Best Available Control Technology (BACT) for several wastewater streams, including flue gas desulphurization (FGD) water, bottom ash transport water and coal combustion landfill leachate. In October 2020, the EPA published a final ELG Rule allowing re-use of bottom ash transport water in FGD scrubber systems with limited discharges related to maintaining system water balance. The rule set technology standards and numerical pollutant limits for discharges of bottom ash transport water and FGD wastewater. Compliance deadlines depend on subcategory, with compliance generally required as soon as possible, beginning after October 13, 2021, but no later than December 31, 2025, or December 31, 2028, in some specific cases. On May 9, 2024, the EPA finalized revisions to the 2020 ELG rule. The final rule establishes zero discharge limitations for bottom ash transport water, FGD wastewater, and combustion residual leachate. A definition for legacy wastewater was established, with deferral to state permit programs for setting discharge limits based on best professional judgment. The rule maintains exemptions for units permanently ceasing coal combustion by 2028 and adds a new subcategory for units that are retiring by 2032 and have already complied with either the 2015 or 2020 ELG rules. Additionally, the rule establishes mercury and arsenic limitations for functionally equivalent discharges of leachate via groundwater to surface water. Compliance deadlines are determined by the applicable state permitting authority through permit incorporation as soon as July 8, 2024, but no later than December 31, 2029. Bottom ash transport and FGD wastewater ELGs are not expected to have a significant impact on Minnesota Power operations. Zero leachate discharge requirements have the potential to impact dewatering associated with the closed Taconite Harbor dry ash landfill. New limitations for arsenic and mercury related to functionally equivalent (groundwater to surface water) discharges are not currently anticipated to impact Minnesota Power facilities. NOTE 6. COMMITMENTS, GUARANTEES AND CONTINGENCIES (Continued) Environmental Matters (Continued) We estimate no additional material compliance costs for ELG bottom ash water and FGD requirements. Compliance costs we might incur related to other ELG waste streams (e.g., leachate) or other potential future water discharge regulations at Minnesota Power facilities cannot be estimated; however, the costs could be material, including costs associated with wastewater treatment and re-use. Minnesota Power would seek recovery of additional costs through a rate proceeding. On June 30, 2025, the EPA announced its intent to update the 2024 final ELG Rule by extending certain compliance deadlines and exploring other potential compliance flexibility for sources. To accomplish this, the EPA currently plans to issue both a direct final rule and several proposed rulemaking notices beginning in the second or third quarter of 2025, with final action anticipated by the end of 2025. Permitted Water Discharges – Sulfate. In 2017, the MPCA released a draft water quality standard in an attempt to update Minnesota’s existing 10 mg/L sulfate limit for waters used for the production of wild rice with the proposed rulemaking heard before an administrative law judge (ALJ). In 2018, the ALJ rejected significant portions of the proposed rulemaking and the MPCA subsequently withdrew the rulemaking. The existing 10 mg/L limit remains in place, and primarily affects Boswell’s discharge. Boswell received a NPDES Wastewater Permit that includes site specific sulfate limits that will not materially impact operations. We are unable to determine the specific impacts these requirements may have on other Minnesota Power operations or its customers, if any. Solid and Hazardous Waste. The Resource Conservation and Recovery Act of 1976 regulates the management and disposal of solid and hazardous wastes. We are required to notify the EPA of hazardous waste activity and, consequently, routinely submit reports to the EPA. Coal Ash Management Facilities. Minnesota Power produces the majority of its coal ash at Boswell, with small amounts of ash generated at Hibbard Renewable Energy Center. Ash storage and disposal methods include storing ash in clay-lined onsite impoundments (ash ponds), disposing of dry ash in a lined dry ash landfill, applying ash to land as an approved beneficial use, and trucking ash to state permitted landfills. Boswell Ash Wastewater Spill. On August 12, 2024, Minnesota Power received a Notice of Violation (NOV) from the MPCA, related to the spill at Boswell from a pipeline carrying ash wastewater from an inactive onsite storage pond to Blackwater Lake, which the Company reported on July 16, 2024. Minnesota Power responded to the MPCA NOV, clarifying certain statements made by the MPCA, as well as providing a written report and required plans. Minnesota Power continues to work with state and federal agencies to evaluate and remediate the impacts from this event. We incurred remediation costs of approximately $2 million pre-tax in the first half of 2025. We are unable to predict the total amount of remediation and other costs or potential financial penalties related to the ash wastewater spill at this time; however, the amounts could be material. Coal Combustion Residuals from Electric Utilities. In 2015, the EPA published a final rule (2015 Rule) regulating CCR as nonhazardous waste under Subtitle D of the Resource Conservation and Recovery Act (RCRA) in the Federal Register. The rule included additional requirements for new landfill and impoundment construction as well as closure activities related to certain existing impoundments. Costs of compliance for Boswell and Laskin are expected to be incurred primarily over the next 12 years and be between approximately $65 million and $120 million. Compliance costs for CCR at Taconite Harbor are not expected to be material. Minnesota Power would seek recovery of additional costs through a rate proceeding. Minnesota Power continues to work on minimizing compliance costs through evaluation of beneficial re-use and recycling of CCR. In 2018, a U.S. District Court for the District of Columbia decision vacated specific provisions of the CCR rule, which resulted in a change to the status of existing clay-lined impoundments at Boswell being considered unlined. In September 2020, the EPA finalized the CCR Part A Rule, which required all unlined impoundments to cease disposal and initiate closure. Upon completion of dry ash conversion activities, Boswell ceased disposal in both impoundments in September 2022. Both impoundments are now inactive and have initiated closure. NOTE 6. COMMITMENTS, GUARANTEES AND CONTINGENCIES (Continued) Environmental Matters (Continued) On May 8, 2024, the EPA's final CCR Legacy Impoundment Rule was published in the Federal Register. The final rule expands the scope of units regulated under the CCR rule to include legacy ponds (inactive surface impoundments at inactive facilities) and creates a new category of units called CCR management units (CCRMU), which includes inactive and closed impoundments and landfills as well as other non-containerized accumulations of CCR. The final rule requires all regulated generating facilities to evaluate and identify past deposits of CCR materials on their sites and close or re-close existing CCR units to meet current closure standards, as well as install groundwater monitoring systems, conduct groundwater monitoring, and implement groundwater corrective actions as necessary. The Final Rule requires a Facility Evaluation Report by February 2027, which will identify regulated units and applicable requirements. Additionally, the EPA finalized portions of the proposed CCR Part B Rule, which allows CCR units to certify closure while conducting groundwater remediation activities. On July 22, 2025, the EPA published a proposed CCRMU Deadline Extension Rule to extend certain CCRMU compliance deadlines by at least one year, including reporting, groundwater monitoring, and closure requirements. We are unable at this time to predict the total impact of compliance relief if the extension rule is finalized; however, any lessened costs are not expected to be material. Impacts to previously closed CCR units at Boswell and Laskin are anticipated from the CCR Legacy Rule. Compliance costs for Minnesota Power’s Boswell and Laskin facilities are estimated to be between approximately $50 million and $85 million and are expected to be incurred over the next 10 years based on our preliminary assessment. These estimates may be revised as Minnesota Power completes the required facility evaluations. Minnesota Power is expected to seek recovery of these costs through a rate proceeding. The Company included in its 2024 Remaining Life Depreciation Petition filed with the MPUC on September 24, 2024, an additional $67.8 million, the average of the estimated cost range, for the expected investigative costs and the increase in depreciation expense for these facilities. Furthermore, a petition seeking approval of deferred cost accounting treatment for these CCR Legacy Rule compliance costs was filed with the MPUC on December 30, 2024. We are currently recording depreciation expense related to this rule on the Consolidated Statement of Income, which would be moved to a deferred tracking account for MPUC review in a future rate case or other proceeding if the MPUC approves our request for deferral accounting treatment. We are unable to predict the outcome of this proceeding. Additionally, the EPA released a proposed CCR Part B rulemaking in February 2020 addressing options for beneficial reuse of CCR materials, alternative liner demonstrations and other CCR regulatory revisions. Portions of the Part B rule addressing alternative liner equivalency standards were finalized in November 2020. A final rule establishing the remaining CCR beneficial reuse requirements is expected but has been moved to EPA’s long-term rulemakings, without a publication target date currently. According to its latest Unified Agenda, the EPA had planned to publish the final CCR federal permit rule implementing a permitting program for tribal lands and nonparticipating states in December 2024, but that did not occur. Other Matters Letters of Credit, Surety Bonds and Other Indemnifications. We have multiple credit facility agreements in place that provide the ability to issue standby letters of credit to satisfy contractual security requirements across our businesses. As of June 30, 2025, we had $139.6 million of outstanding letters of credit issued, including those issued under our revolving credit facility, and $133.2 million in outstanding surety bonds. We do not believe it is likely that any of these outstanding letters of credit or surety bonds will be drawn upon. In 2024 and 2025, under the tax credit transferability provision of the Inflation Reduction Act, we entered into agreements with third parties to sell a portion of our renewable tax credits; to date, under these agreements we have indemnified the parties for approximately $88.1 million of renewable tax credits. ALLETE has indemnified the parties for specified claims for reduction, loss, or disallowance of the transferred tax credits on an after-tax basis. Regulated Operations. As of June 30, 2025, we had $33.9 million outstanding in standby letters of credit and surety bonds at our Regulated Operations which are pledged as security to MISO, the NDPSC and state agencies. ALLETE Clean Energy. ALLETE Clean Energy is party to PSAs that expire in various years between 2027 and 2039. As of June 30, 2025, ALLETE Clean Energy has $86.7 million outstanding in standby letters of credit and surety bonds, the majority of which are pledged as security under these PSAs. New Energy. As of June 30, 2025, New Energy had standby letters of credit outstanding of $12.7 million related to the development of renewable energy projects. Corporate and Other. BNI Energy. As of June 30, 2025, BNI Energy had surety bonds outstanding of $99.7 million related to the reclamation liability for closing costs associated with its mine and mine facilities. Although its coal supply agreements obligate the customers to provide for the closing costs, additional assurance is required by federal and state regulations. BNI Energy’s total reclamation liability is currently estimated at $99.5 million. BNI Energy does not believe it is likely that any of these outstanding surety bonds will be drawn upon. Investment in Nobles 2. The Nobles 2 wind energy facility requires standby letters of credit as security for certain contractual obligations. As of June 30, 2025, ALLETE South Wind has $10.1 million outstanding in standby letters of credit, related to its portion of the security requirements relative to its ownership in Nobles 2. South Shore Energy. As of June 30, 2025, South Shore Energy had $29.7 million outstanding in standby letters of credit pledged as security in connection with the development of NTEC. Legal Proceedings. We are involved in litigation arising in the normal course of business. Also in the normal course of business, we are involved in tax, regulatory and other governmental audits, inspections, investigations and other proceedings that involve state and federal taxes, safety, and compliance with regulations, rate base and cost of service issues, among other things. We do not expect the outcome of these matters to have a material effect on our financial position, results of operations or cash flows. Three complaints have been filed against ALLETE and its directors. The first was filed on July 1, 2024, in the U.S. District Court for the Southern District of New York, alleging violation of Sections 14(a) and 20(a) of the Securities Exchange Act of 1934, disclosure deficiency in the Preliminary Proxy, and seeking to enjoin the transaction until certain disclosures are corrected. On September 3, 2024, that complaint was voluntarily dismissed without prejudice. Two additional complaints were filed on August 6, 2024, and August 7, 2024, in the New York State Supreme Court, alleging negligent misrepresentation and negligence related to alleged deficiencies in the Preliminary Proxy. Those complaints have not been served on any defendant. The Company believes that the remaining complaints are without merit.

Power Purchase and Sale Agreements. Our long-term PPAs have been evaluated under the accounting guidance for variable interest entities. We have determined that either we have no variable interest in the PPAs or, where we do have variable interests, we are not the primary beneficiary; therefore, consolidation is not required. These conclusions are based on the fact that we do not have both control over activities that are most significant to the entity and an obligation to absorb losses or receive benefits from the entity’s performance. Our financial exposure relating to these PPAs is limited to our capacity and energy payments.

Square Butte PPA. As of June 30, 2025, Square Butte had total debt outstanding of $157.6 million. Fuel expenses are recoverable through Minnesota Power’s fuel adjustment clause and include the cost of coal purchased from BNI Energy under a long-term contract. Minnesota Power’s cost of power purchased from Square Butte during the six months ended June 30, 2025, was $40.9 million ($44.2 million for the same period in 2024). This reflects Minnesota Power’s pro rata share of total Square Butte costs based on the 50 percent output entitlement. Included in this amount was Minnesota Power’s pro rata share of interest expense of $2.1 million ($2.6 million for the same period in 2024). Minnesota Power’s payments to Square Butte are approved as a purchased power expense for ratemaking purposes by both the MPUC and the FERC.

Minnkota Power PSA. Minnesota Power has a PSA with Minnkota Power, which commenced in 2014. Under the PSA, Minnesota Power is selling a portion of its entitlement from Square Butte to Minnkota Power, resulting in Minnkota Power’s net entitlement increasing and Minnesota Power’s net entitlement decreasing until Minnesota Power’s share is eliminated at the end of 2025. Of Minnesota Power’s 50 percent output entitlement, Minnesota Power sold to Minnkota Power approximately 46 percent in 2025 and 41 percent in 2024.

Coal, Rail and Shipping Contracts. Minnesota Power has coal supply agreements providing for the purchase of a significant portion of its coal requirements through December 2027. Minnesota Power also has coal transportation agreements in place for the delivery of a significant portion of its coal requirements through December 2027. The costs of fuel and related transportation costs for Minnesota Power’s generation are recoverable from Minnesota Power’s utility customers through the fuel adjustment clause.

Our businesses are subject to regulation of environmental matters by various federal, state, and local authorities. A number of regulatory changes to the Clean Air Act, the Clean Water Act and various waste management requirements have been promulgated by both the EPA and state authorities over the past several years. Minnesota Power’s facilities are subject to additional requirements under many of these regulations. Minnesota Power is reshaping its generation portfolio, over time, to reduce its reliance on coal, has installed cost-effective emission control technology, and advocates for sound science and policy during rulemaking implementation.

We consider our businesses to be in substantial compliance with currently applicable environmental regulations and believe all necessary permits have been obtained. We anticipate that with many state and federal environmental regulations and requirements finalized, or to be finalized in the near future, potential expenditures for future environmental matters may be material and require significant capital investments. Minnesota Power has evaluated various environmental compliance scenarios using possible outcomes of environmental regulations to project power supply trends and impacts on customers.

We review environmental matters on a quarterly basis. Accruals for environmental matters are recorded when it is probable that a liability has been incurred and the amount of the liability can be reasonably estimated based on current law and existing technologies. Accruals are adjusted as assessment and remediation efforts progress, or as additional technical or legal information becomes available. Accruals for environmental liabilities are included in the Consolidated Balance Sheet at undiscounted amounts and exclude claims for recoveries from insurance or other third parties. Costs related to environmental contamination treatment and cleanup are expensed unless recoverable in rates from customers.

Federal Environmental Regulatory Agenda. On March 12, 2025, the EPA announced its intent to reevaluate or reconsider numerous environmental regulations. This list includes various air, water, and waste environmental regulatory actions, many of which apply at the Company. The specific timing or outcome of this initiative is not yet known, but regular required rulemaking processes and procedures still apply, and litigation may also occur. The following disclosures do not attempt to discern potential impacts of these deregulatory actions until and unless formal rulemaking or other regulatory actions are announced and the potential impacts to ALLETE operations can be discerned. We are unable to predict the outcome of the reevaluation or reconsideration of these environmental regulations.

Air. The electric utility industry is regulated both at the federal and state level to address air emissions. Minnesota Power’s thermal generating facilities mainly burn low-sulfur western sub-bituminous coal, as well as natural gas and biomass. All of Minnesota Power’s coal-fired generating facilities are equipped with pollution control equipment such as scrubbers, baghouses and low NOX technologies. Under currently applicable environmental regulations, these facilities are substantially compliant with emission requirements.

Cross-State Air Pollution Rule (CSAPR). The CSAPR requires certain states in the eastern half of the U.S., including Minnesota, to reduce power plant emissions that contribute to ozone or fine particulate pollution in other states. The CSAPR does not require installation of controls but does require facilities have sufficient allowances to cover their emissions on an annual basis. These allowances are allocated to facilities from each state’s annual budget and can be bought and sold. Based on our review of the NOX and SO2 allowances issued and pending issuance as well as consideration of current rules, we currently expect generation levels and emission rates will result in continued compliance with the CSAPR. Minnesota Power will continue to monitor ongoing CSAPR rulemakings and compliance implementation, including the EPA’s Good Neighbor Rule which modifies certain aspects of the CSAPR’s program scope and extent (see EPA Good Neighbor Plan for 2015 Ozone NAAQS).

National Ambient Air Quality Standards (NAAQS). The EPA is required to review each NAAQS every five years. If the EPA determines that a state’s air quality is not in compliance with the NAAQS, the state is required to adopt plans describing how it will reduce emissions to attain the NAAQS. Minnesota Power actively monitors NAAQS developments, and the EPA has recently reassessed several primary and secondary NAAQS for NOx, SO2, and particulate matter. Implementation of the EPA’s February 2024 final rule lowering the annual primary standard for fine particulate matter began on May 6, 2024. On December 27, 2024, the EPA published a final rule in the Federal Register revising the secondary SO2 NAAQS while retaining the NOX and particulate matter secondary standards, with a final rule effective date of January 27, 2025. Anticipated timelines and compliance costs related to this and other potential NAAQS revisions cannot yet be estimated but costs could be material. Minnesota Power would seek recovery of additional costs through a rate proceeding.

EPA Good Neighbor Plan for 2015 Ozone NAAQS. On June 5, 2023, after disapproving state implementation plans, the EPA published a final Federal Implementation Plan (FIP) rule in the Federal Register, the Good Neighbor Plan, to address regional ozone transport for the 2015 Ozone NAAQS by reducing NOX emissions during the period of May 1 through September 30 (ozone season). In its justification for the final rule, the EPA asserted that 23 states, including Minnesota, were modeled as significant contributors to downwind states’ challenges in attaining or maintaining ozone NAAQS compliance within their state borders. The Good Neighbor Plan is designed to resolve this interstate transport issue by implementing a variety of NOX reduction strategies, including federal implementation plan requirements, NOX emission limitations, and ozone season allowance program requirements. The final rule imposed restrictions on fossil-fuel fired power plants in 22 states and on certain industrial sources in 20 states, with implementation occurring through changes to the existing CSAPR program for power plants.

Since the EPA partially disapproved the Good Neighbor State Implementation Plans (SIPs) for the states of Minnesota and Wisconsin, among others, Minnesota became subject to the final Good Neighbor Plan. However, Minnesota Power and a coalition of other Minnesota utilities and industry (the parties) co-filed challenges to the EPA’s final Minnesota SIP disapproval, submitting a petition for reconsideration and stay to the EPA, and a petition for judicial review to the Eighth Circuit Court. The parties are challenging and requesting reconsideration of certain technical components of the EPA’s review and subsequent partial disapproval of the state of Minnesota’s SIP. In July 2023, the Eighth Circuit Court granted a stay of the SIP disapproval preventing the Good Neighbor Plan from taking effect in Minnesota; oral arguments occurred in October 2024. In April 2024, the EPA published a partial denial of several administrative reconsideration and stay petitions, including from the Minnesota coalition. On September 29, 2023, the EPA issued an updated final interim rule addressing the stays in Minnesota and five other states, formally delaying the effective date of the final FIP for states with active stays in place. The state of Minnesota therefore did not become subject to compliance obligations for the 2023, 2024, or 2025 ozone seasons.

Future compliance obligations will depend on resolution of the stay and outcomes of related litigation. Additional challenges have been filed against the final FIP rule by the Minnesota coalition parties and other entities, although the Minnesota coalition FIP challenge is currently in abeyance pending resolution of the SIP disapproval case. On June 27, 2024, the U.S. Supreme Court granted an emergency stay of the FIP rule requested by several states and industry groups, staying enforcement pending the D.C. Circuit’s review and any petition for writ of certiorari. In response to the U.S. Supreme Court’s stay order, the EPA published a third interim rule in the Federal Register on November 6, 2024, staying the effectiveness of the Good Neighbor FIP in the 10 remaining covered states, including Wisconsin. On March 10, 2025, the EPA filed a motion with the D.C. Circuit requesting a voluntary remand of its FIP, stating they anticipate completing replacement rulemaking by Fall 2026, and on March 12, 2025, the EPA also listed the Good Neighbor Plan reconsideration among its announcement of 31 proposed actions to reconsider EPA rules. Anticipated timelines and compliance costs related to final Good Neighbor Plan compliance cannot yet be estimated due to uncertainties about SIP approval resolution, implementation timing, FIP rule outcome, and allowance costs and facility emissions during the ozone season. However, the costs could be material, including costs of additional NOx controls, emission allowance program participation, or operational changes, if any are required. Minnesota Power would seek recovery of additional costs through a rate proceeding. Additionally, final rates in Minnesota Power’s most recent rate case were implemented on March 1, 2025, allowing any necessary allowance purchase costs to transfer to the fuel adjustment clause.

EPA National Emission Standards for Hazardous Air Pollutants for Major Sources: Industrial, Commercial and Institutional Boilers and Process Heaters (Industrial Boiler MACT) Rule. A final rule issued by the EPA for Industrial Boiler MACT became effective in 2013 with compliance required at major existing sources in 2016, which applied to Minnesota Power’s Hibbard Renewable Energy Center and Rapids Energy Center. Compliance consisted largely of adjustments to fuels and operating practices and compliance costs were not material. After this initial rulemaking, litigation from 2016 through 2018 resulted in court orders directing that the EPA reconsider certain aspects of the regulation. A final rule incorporating these revisions became effective in December 2022, with a compliance deadline of October 6, 2025. Compliance costs are not expected to be material.

EPA Mercury and Air Toxics Standards (MATS) Rule. On May 7, 2024, the EPA promulgated a final rule to revise the existing 2012 MATS Rule, which regulates air emissions of hazardous air pollutants from coal- and oil-fired electric generating units (EGUs). The final rule eliminates certain MATS compliance flexibility, lowers the particulate emission standard for all coal-fired EGUs, and reduces the mercury emission standard for lignite-fired EGUs. The rule became effective July 8, 2024, with compliance required beginning July 6, 2027. The MATS regulation applies at Minnesota Power’s Boswell facility, which is currently well-controlled for these emissions and already complying with some of the new requirements. The Company anticipates the new rule will not have material impacts at Boswell. However, compliance costs cannot yet be fully estimated, and recovery of any additional costs would be sought through a rate proceeding. Litigation against the EPA’s latest MATS rule revision from a number of U.S. states, as well as several companies and industry groups, is ongoing. Motions to stay the rule were denied by the U.S. Court of Appeals for the D.C. Circuit on August 6, 2024, and the U.S. Supreme Court on October 4, 2024. On April 8, 2025, President Trump issued a proclamation entitled Regulatory Relief for Certain Stationary Sources to Further Promote American Energy granting a two-year compliance extension deadline to “certain stationary sources” subject to the 2024 MATS Rule. The list of the specific facilities who may qualify for the exemption has not yet been made available.

On April 8, 2025, President Trump issued a proclamation entitled Regulatory Relief for Certain Stationary Sources to Further Promote American Energy. Pursuant to this proclamation, a two-year compliance extension deadline was granted on April 14, 2025 to 47 specific listed sources subject to the 2024 MATS rule, exempting those sources from compliance obligations of the 2024 rule until July 8, 2029; another proclamation was subsequently issued for several additional sources on July 17, 2025. Minnesota Power did not request a deadline extension. Subsequently, the EPA published a proposed rule on June 17, 2025, repealing the majority of the 2024 final MATS rule. The Company anticipates this proposed rule will not have material impact at Boswell.

Climate Change. The scientific community generally accepts that emissions of GHGs are linked to global climate change which creates physical and financial risks. Physical risks could include but are not limited to: increased or decreased precipitation and water levels in lakes and rivers; increased or other changes in temperatures; increased risk of wildfires; and changes in the intensity and frequency of extreme weather events. These all have the potential to affect the Company’s business and operations. We are addressing climate change by taking the following steps that also ensure reliable and environmentally compliant generation resources to meet our customers’ requirements:

EPA Regulation of GHG Emissions. On April 25, 2024, the EPA issued several final greenhouse gas regulations to establish emissions standards and guidelines for fossil fuel-fired electric generating units (EGUs) under Section 111 of the Clean Air Act (CAA). The final rules revise new source performance standards (NSPS) for new, modified and reconstructed EGUs (Section 111(b) of the CAA) and creates new emission guidelines for existing EGUs (Section 111(d) of the CAA). The action also officially repeals the predecessor regulation “Affordable Clean Energy Rule”, first issued in 2019 and later vacated in 2021. Compliance will be required beginning January 1, 2030, for existing sources, and upon commencing operation of new units. The 111(d) rule also requires states to submit plans to provide for the establishment, implementation and enforcement of performance standards for existing sources. States must submit either a state plan or negative declaration letter to the EPA by May 11, 2026.

The final Section 111 rules apply to several Company assets, including existing EGUs at the Boswell and Laskin facilities as well as the proposed combined cycle natural gas-fired generating facility, Nemadji Trail Energy Center. The Company anticipates compliance with the rules may require operational or planning adjustments. The state implementation plan process for Section 111(d) existing units will also be a factor in determining specific requirements and timing. We are unable to predict compliance costs at this time; however, the costs could be material. Minnesota Power would seek recovery of additional costs through a rate proceeding. The Company is also monitoring endangerment finding evaluations by the EPA, as well as litigation of the final Section 111 rules. Litigation began when the rules were published in the Federal Register on May 9, 2024, and continues in federal court. Both the D.C. Circuit and the U.S. Supreme Court have declined requests to block the rule from becoming effective while litigation is ongoing. Oral arguments in the D.C. Circuit occurred on December 6, 2024, with a merits decision expected in mid-2025; however, currently the case remains in continued abeyance at the EPA’s request while the EPA reconsiders the Section 111 regulations. The EPA has stated it anticipates issuing a final reconsideration rule by December 2025.

On June 17, 2025, the EPA published a proposed rule titled Repeal of Greenhouse Gas Emissions Standards for Fossil Fuel-Fired Electric Generating Units (reconsideration rule) that, if finalized, would repeal either all or certain aspects of the 2024 Section 111 rules. Outcomes from ongoing litigation over the 2024 Section 111 rules, the outcome of the proposed reconsideration rule, and the effects of future litigation will determine the timing of rule effectiveness and the ultimate compliance obligations required by the rule. The EPA also released a proposed rule on July 29, 2025 titled Reconsideration of 2009 Greenhouse Gas Endangerment Finding and Greenhouse Gas Standards seeking to repeal all greenhouse gas emissions standards for vehicles and engines as well as to rescind the EPA’s 2009 endangerment finding related to greenhouse gases. The Company cannot predict the outcome of this rulemaking initiative at this point, but resolution of this matter also has the potential to affect federal greenhouse gas regulations at stationary sources such as power plants.

Steam Electric Power Generating Effluent Limitations Guidelines. In 2015, the EPA issued revised federal effluent limitation guidelines (ELG) for steam electric power generating stations under the Clean Water Act. It set effluent limits and prescribed Best Available Control Technology (BACT) for several wastewater streams, including flue gas desulphurization (FGD) water, bottom ash transport water and coal combustion landfill leachate. In October 2020, the EPA published a final ELG Rule allowing re-use of bottom ash transport water in FGD scrubber systems with limited discharges related to maintaining system water balance. The rule set technology standards and numerical pollutant limits for discharges of bottom ash transport water and FGD wastewater. Compliance deadlines depend on subcategory, with compliance generally required as soon as possible, beginning after October 13, 2021, but no later than December 31, 2025, or December 31, 2028, in some specific cases.

On May 9, 2024, the EPA finalized revisions to the 2020 ELG rule. The final rule establishes zero discharge limitations for bottom ash transport water, FGD wastewater, and combustion residual leachate. A definition for legacy wastewater was established, with deferral to state permit programs for setting discharge limits based on best professional judgment. The rule maintains exemptions for units permanently ceasing coal combustion by 2028 and adds a new subcategory for units that are retiring by 2032 and have already complied with either the 2015 or 2020 ELG rules. Additionally, the rule establishes mercury and arsenic limitations for functionally equivalent discharges of leachate via groundwater to surface water. Compliance deadlines are determined by the applicable state permitting authority through permit incorporation as soon as July 8, 2024, but no later than December 31, 2029.

Bottom ash transport and FGD wastewater ELGs are not expected to have a significant impact on Minnesota Power operations. Zero leachate discharge requirements have the potential to impact dewatering associated with the closed Taconite Harbor dry ash landfill. New limitations for arsenic and mercury related to functionally equivalent (groundwater to surface water) discharges are not currently anticipated to impact Minnesota Power facilities.

We estimate no additional material compliance costs for ELG bottom ash water and FGD requirements. Compliance costs we might incur related to other ELG waste streams (e.g., leachate) or other potential future water discharge regulations at Minnesota Power facilities cannot be estimated; however, the costs could be material, including costs associated with wastewater treatment and re-use. Minnesota Power would seek recovery of additional costs through a rate proceeding. On June 30, 2025, the EPA announced its intent to update the 2024 final ELG Rule by extending certain compliance deadlines and exploring other potential compliance flexibility for sources. To accomplish this, the EPA currently plans to issue both a direct final rule and several proposed rulemaking notices beginning in the second or third quarter of 2025, with final action anticipated by the end of 2025.

Permitted Water Discharges – Sulfate. In 2017, the MPCA released a draft water quality standard in an attempt to update Minnesota’s existing 10 mg/L sulfate limit for waters used for the production of wild rice with the proposed rulemaking heard before an administrative law judge (ALJ). In 2018, the ALJ rejected significant portions of the proposed rulemaking and the MPCA subsequently withdrew the rulemaking. The existing 10 mg/L limit remains in place, and primarily affects Boswell’s discharge. Boswell received a NPDES Wastewater Permit that includes site specific sulfate limits that will not materially impact operations. We are unable to determine the specific impacts these requirements may have on other Minnesota Power operations or its customers, if any.

Coal Ash Management Facilities. Minnesota Power produces the majority of its coal ash at Boswell, with small amounts of ash generated at Hibbard Renewable Energy Center. Ash storage and disposal methods include storing ash in clay-lined onsite impoundments (ash ponds), disposing of dry ash in a lined dry ash landfill, applying ash to land as an approved beneficial use, and trucking ash to state permitted landfills.

Boswell Ash Wastewater Spill. On August 12, 2024, Minnesota Power received a Notice of Violation (NOV) from the MPCA, related to the spill at Boswell from a pipeline carrying ash wastewater from an inactive onsite storage pond to Blackwater Lake, which the Company reported on July 16, 2024. Minnesota Power responded to the MPCA NOV, clarifying certain statements made by the MPCA, as well as providing a written report and required plans. Minnesota Power continues to work with state and federal agencies to evaluate and remediate the impacts from this event. We incurred remediation costs of approximately $2 million pre-tax in the first half of 2025. We are unable to predict the total amount of remediation and other costs or potential financial penalties related to the ash wastewater spill at this time; however, the amounts could be material.

Coal Combustion Residuals from Electric Utilities. In 2015, the EPA published a final rule (2015 Rule) regulating CCR as nonhazardous waste under Subtitle D of the Resource Conservation and Recovery Act (RCRA) in the Federal Register. The rule included additional requirements for new landfill and impoundment construction as well as closure activities related to certain existing impoundments. Costs of compliance for Boswell and Laskin are expected to be incurred primarily over the next 12 years and be between approximately $65 million and $120 million. Compliance costs for CCR at Taconite Harbor are not expected to be material. Minnesota Power would seek recovery of additional costs through a rate proceeding.

Minnesota Power continues to work on minimizing compliance costs through evaluation of beneficial re-use and recycling of CCR. In 2018, a U.S. District Court for the District of Columbia decision vacated specific provisions of the CCR rule, which resulted in a change to the status of existing clay-lined impoundments at Boswell being considered unlined. In September 2020, the EPA finalized the CCR Part A Rule, which required all unlined impoundments to cease disposal and initiate closure. Upon completion of dry ash conversion activities, Boswell ceased disposal in both impoundments in September 2022. Both impoundments are now inactive and have initiated closure.

On May 8, 2024, the EPA's final CCR Legacy Impoundment Rule was published in the Federal Register. The final rule expands the scope of units regulated under the CCR rule to include legacy ponds (inactive surface impoundments at inactive facilities) and creates a new category of units called CCR management units (CCRMU), which includes inactive and closed impoundments and landfills as well as other non-containerized accumulations of CCR. The final rule requires all regulated generating facilities to evaluate and identify past deposits of CCR materials on their sites and close or re-close existing CCR units to meet current closure standards, as well as install groundwater monitoring systems, conduct groundwater monitoring, and implement groundwater corrective actions as necessary. The Final Rule requires a Facility Evaluation Report by February 2027, which will identify regulated units and applicable requirements. Additionally, the EPA finalized portions of the proposed CCR Part B Rule, which allows CCR units to certify closure while conducting groundwater remediation activities. On July 22, 2025, the EPA published a proposed CCRMU Deadline Extension Rule to extend certain CCRMU compliance deadlines by at least one year, including reporting, groundwater monitoring, and closure requirements. We are unable at this time to predict the total impact of compliance relief if the extension rule is finalized; however, any lessened costs are not expected to be material.

Impacts to previously closed CCR units at Boswell and Laskin are anticipated from the CCR Legacy Rule. Compliance costs for Minnesota Power’s Boswell and Laskin facilities are estimated to be between approximately $50 million and $85 million and are expected to be incurred over the next 10 years based on our preliminary assessment. These estimates may be revised as Minnesota Power completes the required facility evaluations. Minnesota Power is expected to seek recovery of these costs through a rate proceeding. The Company included in its 2024 Remaining Life Depreciation Petition filed with the MPUC on September 24, 2024, an additional $67.8 million, the average of the estimated cost range, for the expected investigative costs and the increase in depreciation expense for these facilities. Furthermore, a petition seeking approval of deferred cost accounting treatment for these CCR Legacy Rule compliance costs was filed with the MPUC on December 30, 2024. We are currently recording depreciation expense related to this rule on the Consolidated Statement of Income, which would be moved to a deferred tracking account for MPUC review in a future rate case or other proceeding if the MPUC approves our request for deferral accounting treatment. We are unable to predict the outcome of this proceeding.

Additionally, the EPA released a proposed CCR Part B rulemaking in February 2020 addressing options for beneficial reuse of CCR materials, alternative liner demonstrations and other CCR regulatory revisions. Portions of the Part B rule addressing alternative liner equivalency standards were finalized in November 2020. A final rule establishing the remaining CCR beneficial reuse requirements is expected but has been moved to EPA’s long-term rulemakings, without a publication target date currently. According to its latest Unified Agenda, the EPA had planned to publish the final CCR federal permit rule implementing a permitting program for tribal lands and nonparticipating states in December 2024, but that did not occur.

We have multiple credit facility agreements in place that provide the ability to issue standby letters of credit to satisfy contractual security requirements across our businesses. As of June 30, 2025, we had $139.6 million of outstanding letters of credit issued, including those issued under our revolving credit facility, and $133.2 million in outstanding surety bonds. We do not believe it is likely that any of these outstanding letters of credit or surety bonds will be drawn upon.

In 2024 and 2025, under the tax credit transferability provision of the Inflation Reduction Act, we entered into agreements with third parties to sell a portion of our renewable tax credits; to date, under these agreements we have indemnified the parties for approximately $88.1 million of renewable tax credits. ALLETE has indemnified the parties for specified claims for reduction, loss, or disallowance of the transferred tax credits on an after-tax basis.

BNI Energy. As of June 30, 2025, BNI Energy had surety bonds outstanding of $99.7 million related to the reclamation liability for closing costs associated with its mine and mine facilities. Although its coal supply agreements obligate the customers to provide for the closing costs, additional assurance is required by federal and state regulations. BNI Energy’s total reclamation liability is currently estimated at $99.5 million. BNI Energy does not believe it is likely that any of these outstanding surety bonds will be drawn upon.

We are involved in litigation arising in the normal course of business. Also in the normal course of business, we are involved in tax, regulatory and other governmental audits, inspections, investigations and other proceedings that involve state and federal taxes, safety, and compliance with regulations, rate base and cost of service issues, among other things. We do not expect the outcome of these matters to have a material effect on our financial position, results of operations or cash flows.

Three complaints have been filed against ALLETE and its directors. The first was filed on July 1, 2024, in the U.S. District Court for the Southern District of New York, alleging violation of Sections 14(a) and 20(a) of the Securities Exchange Act of 1934, disclosure deficiency in the Preliminary Proxy, and seeking to enjoin the transaction until certain disclosures are corrected. On September 3, 2024, that complaint was voluntarily dismissed without prejudice. Two additional complaints were filed on August 6, 2024, and August 7, 2024, in the New York State Supreme Court, alleging negligent misrepresentation and negligence related to alleged deficiencies in the Preliminary Proxy. Those complaints have not been served on any defendant. The Company believes that the remaining complaints are without merit.