Document 828dRK6wVBE7pZEQbV0YzO1Ko

215 South Cascade Street PO Box 496 Fergus Falls, Minnesota 56538-0496 218 739-8200 www.otpco.com Via email at airaction@_epa.gov March 31, 2025 I Imorable nee M. Zeldin Office of the Administrator (1101A) United States Environmental Protection Agency 1200 Pennsylvania Avenue, I.W. Washington, D.C. 20460 OrrERTAn POWER COMPANY RE: Presidential Exemption: National Emission Standards.fOr Hazardous Air Pollutants: Coal- and Oil-Fired Electric Steam Generating (fnits Review of the Residual Risk and Technology Review (MA IS RIR), 89 Fed. 38508 (May 7, 2024): Big Stone Plant, Near Big Stone City, South Dakota Dear Administrator Zeldin: Otter Tail Power Company (Otter Tail), as operator on behalf of Co-owners of Big Stone Plant (Big Stone) `, respectfully requests a Presidential Exemption under Section 1 12(i)(4) of the Clean Air Act from compliance with the revised standards and requirements finali7ed in the above-referenced MATS RTR rule (MATS RTR or the Rule). Otter Tail' and the Co-owners3A arc seeking a two-year exemption from the current compliance date ofJuly 6, 2027 (as calculated, July 6, 2029) for Big Stone, with the potential for a further extension, as allowed under Section 1 12(i)(4). 1. Executive Summary Otter Tail and the Co-owners seek an exemption from compliance with the MATS RTR emissions standards for Big Stone, which combusts subbituminous coal. Otter Dail and the Coowners seek an exemption for a two-year period from the current compliance date, extending to July 6, 2029. We support this request with information regarding the following: Otter Tail is a co-owner and the operating agent for Big Stone. The other co-owners are Montana-Dakota Utilities Co. and NorthWestern Energy Public Service Corporation (the Co-owners). Otter Tail makes this request as the operating agent for the Plant and has authority make this request on behalf of the Co-owners. Otter 'Jail is an electric utility that provides generation, transmission, and distribution of electricity and energy services for approximately 133,000 residential, commercial, and industrial customers across 70,000 square miles in Minnesota, North Dakota, and South Dakota Montana-Dakota Utilities Co. is a subsidiary of MDU Resource Group, Inc engaged in the distribution of natural gas and the generation, transmission, and distribution of electricity in the states of North Dakota, South Dakota, Montana, and Wyoming Montana-Dakota provides electric service at retail, serving 145,686 residential, commercial, industrial and municipal customers in 185 communities and adjacent rural areas as of 2024. NorthWestern Energy Public Service Corporation, a wholly owned subsidiary of NorthWestern Energy Group, Inc., has provided electricity and / or natural gas to customers in South Dakota and Nebraska since 1923. Sierra Club FOIA 2025-EPA-04883 ED_018388_00000190- 00001 SC_EVERSPLIT0005956