Document xzmovweXJazkyaaMoxQb1Nbx1

unresolved challenges associated with the requirement to demonstrate compliance with the revised fPM limitation via PM CEMS, EPA has announced the potential availability of such exemptions and asked that requests for exemptions be submitted by March 31. See [ HYPERL1NK "https://www.cpa.govistationary-sources-air-pollution/clean-air-act-section-112-presidentialexemption-information" ] Consistent with that announcement, and for the reasons set forth below, PPES requests a two-year exemption from the [PM standard and the requirement to install and use CEMS. Section I of this request explains that the technology required to meet the Rule's lower fPM standard on a continuous basis is not considered available and Section II explains that the type of CEMS that can measure the lower EPM standard arc likewise unavailable. Section Iii finds that it is in the national security interest to issue an exemption from compliance with the MA I'S revisions. The Particulate Control Technology Required to Implement the Rule's fPM Standard is Not Available The MATS revisions require coal-fired units to meet a more stringent fPM limit of 0.010 lb/MMBtu. There are technological and operational limitations, as well as substantial costs, that make it difficult to meet the revised limit by July 8, 2027. There are technological and economic harriers that make upgrades to existing fPM controls or the addition of new fPM controls "not available." During rulemaking, EPA did not fully consider the availability of upgrades to fPM control technologies that could be required to meet the revised limit and the costs associated with those controls. ,Sec Perrs' Brief at 68-69, North Dakota v. EPA. No. 24-1119, Doc. 2077742 (Oct. 1, 2024). Whether a control technology is available includes consideration of the emission reductions achievable, as well as the economic impacts and costs associated with the control technology. PPES currently has a baghouse it uses to control fPM emissions. Even with the current baghouse which, without upgrades may not be able to meet the revised [PM limit operational realities can hinder the ability to continuously comply with the revised fi'M limit. Notably, EPA based its decision to lower the fPM limit on select data from only a few units, see Per rs' Brief at 6568. Moreover, the variable characteristics of coal (e.g. ash content) can impact the ability of a unit to continuously comply with the re`ised fi'M limit, regardless of the effectiveness of the control technologies in place. without equipment upgrades. Other operational factors, such as cleaning frequency, operational duration, and filter change-out frequency of haghouses, impact the performance of fPM controls and, thus, the ability for a unit to implement the revised fPM limit without upgrades or additional technology. PPES is currently conducting an evaluation to determine the required technical upgrades to the baghouse PM emission controls needed to comply with the more stringent fPM limitation. To implement the most effective and sustainable solution, PPES will need additional evaluation of available technologies. This process is crucial for identifying the best possible upgrades that will meet regulatory standards without causing significant downtime and disruption to our operations. Implementing any possible upgrades without a thorough feasibility study and adequate planning could lead to operational inefficiencies and potential compliance issues. Plus, any potential upgrade 2 Sierra Club FOIA 2025-EPA-04883 ED_018388_00000201-00002 SC_EVERSPLIT0005974