Document 8RkdmE1n617Oa36DmgVjzy6r5

Oak Grove Management Company LLC Oak Grove Steam Electric Station 6555 Sierra Drive Irving, TX 75039 March 31, 2025 Submitted via email to airaction(depa.gov President Donald J. 'Frump do Administrator Leo M. Zeldin Office of the Administrator (1101A) L.S. Environmental Protection Agency 1200 Pennsylvania Avenue, I.W. Washington, D.C. 20460 Re: Presidential Exemption: National Emission Standardsfor Hazardous Air Pollutants: Coal- and Oil-Fired Electric Utility Steam Generating Units Review of the Residual Risk and Technology Review, 89 Fed. Reg. 38,508 (May 7, 2024): Oak Grove Steam Electric Station Units 1 and 2. Dear President Trump: Please accept this letter on behalf of Oak Grovc Management Company LLC requesting a Presidential exemption under Section 1 12(i)(4) of the Clean Air Act ("CAA") from compliance with (1) the mercury standard, and (2) the filterable particulate matter ("fPM") surrogate emission standard for non-mercury metal hazardous air pollutants ("I IAP") and requirement to install continuous emissions monitoring systems ("CEMS" or "PM CEMS") under the above-referenced rule (the "MATS RTR" or the "Rule") for the Oak Grove Steam Electric Station ("Oak Grovc"). Oak Grove is requesting a two-year exemption, beginning July 6, 2027, from those requirements for Oak Grove Units 1 and 2. The MATS RTR amended 40 C.F.R. Part 63 Subpart UUUUU and became effective on July 8, 2024. Under the Rule, lignite-fired electric generating units ("EGUs") arc required to reduce mercury omissions by 70% to moot a new omissions standard of 1.2 lb/TBtu. Notably, EPA has previously agreed that there is no health-based need for this requirement. Oak Grove is also required to reduce fPM emissions from 0.030 lb/MM13tu to 0.010 lb/MMBtu. Compliance with this revised f-PM limit is based on a continuous, 30-day rolling limit. In addition, the Rule requires all coal-fired EGUs to use CEMS to implement the revised fPM standard, which may not be technically feasible at the lower fPM standard. The compliance deadline for mooting the revised mercury standard, [PM standard, and for using PM CEMS is July 6, 2027, but work to design, purchase, and install the necessary emission controls and implement required adjustments to the CEMS would need to begin much sooner. Under Section 112(i)(4) of the Clean Air Act, the President may issue exemptions "from compliance with any standard or limitation under this section for a period of not more than 2 years if the President determines that the technology to implement such standard is not available and 1 Sierra Club FOIA 2025-EPA-04883 ED_018388_00000159-00001 SC_EVERSPLIT0005925