Document nk6Zm5roQdMYgk8Mm4oeYRZBR

that it is in the national security interests of the United States to do so." 42 U.S.C. 7412(i)(4). Accordingly, the President is authorized to exercise his discretion to exempt Martin Lake Units 13 from complying with the standards set forth in the MATS RTR where (1) the technology required "to implement" the Rule's standard is not available and (2) where it is in the interest of national security. ln light of this authority, and in light of the burden imposed on electric generating facilities by the MA IS R fR. EPA has announced the potential availability of such exemptions and asked that requests for exemptions he submitted by March 31. See https://www.epa.2ovistationary-sources-air-pol luti onicl oan-ai r-act-section-112-presidentialexemption-information. Consistent with that announcement, and for the reasons set forth below, Luminant requests a 2-year exemption for Martin Lake from the fPM standard and the requirement to implement changes to the CEMS. Section 1 explains that the technology required to implement the Rule's revised fPM standard is not considered available on a continuous basis and that the related CEMS changes are likewise unavailable. Section 11 concludes that it is in the national security interest to issue an exemption from compliance with the MATS RTR. I. Particulate Control Technology and CENTS Technology is Not Available As an initial matter, EPA has been very clear that the revised fPM standard and CEMS requirement arc completely integrated, such that any exemption must cover both requirements in the Rule. Specifically, EPA explained "that a fPM standard of 0.010 lb/MMBtu ... is the lowest fPM emission limit possible at this time with use of PM CEMS." 89 Fed. Reg. at 38,534. And EPA identified the revised [PM standard and the PM CEMS requirement as a combined "twopronged approach," stating that "requiring PM CEMS in addition to a lower [PM limit . . . is the most stringent option that balances the benefits of using PM CEMS with the emission reductions associated with the tightened fPM omission standard." Id. at 38,530. In other words, EPA's effort "to implement" its revised standard depends equally on both the more stringent numeric standard for fPM and on the obligation to install new monitoring equipment. Part A explains that the technology required to implement the Rule's revised fPM standard is "not available," and Part B explains that changes to the CEMS are likewise unavailable. Given the interdependence of those requirements, however, the unavailability of technology as to either component makes "implementation" of the standard likewise unavailable for the other. a. The Particulate Control Technology Required to Implement the Rule's fPNI Standard is Not Available There arc technological and operational limits at Martin Lake that make it extremely difficult and expensive to meet the revised 1PM standard. EPA based its decision to lower the fPM standard on data from only a select few units, sec Pot'rs' Brief at 65-68, North Dakota v. EPA, No. 24-1119, Doc. 2077742 (Oct. 1, 2024), but not all units can meet the revised limit under all operating conditions. In fact. EPA specifically identified Martin Lake Units 1 and 3 as units that they believe would require changes to their controls to meet the revised fPNI limits. Martin Lake currently utilizes an Electrostatic Precipitator ("ESP") for particulate control, and EPA estimates that the upgrades for only two of the throe Martin Lake units would be 5100 million. See EPA. 2023 lechnology Review .fie. the ('oui- and Oil-Mired ,S"orce Category, Docket No. EPA-HQOAR-2018-0794-5789, at 2 (Jan. 2023). Even these cost estimates underestimate the actual costs 2 Sierra Club FOIA 2025-EPA-04883 ED_018388_00000157-00002 SC_EVERSPLIT0005921