Document EqpdJG4d0VVmewJKnmZM7rBxx

TALEN le' ll MONTANA from the initial correlation by 25% or more of the CAM Plan excursion limit, then the initial correlation will be repeated. An on-going PM CEMS correlation adjustment will be made quarterly based on the correlation from all RM5 test data. PM CEMS daily averages are submitted to MDEQ on a quarterly basis. Given Colstrip's experience with the use of. PM CEMS as a performance indicator, which shows that the CEMS results are highly variable and not reliable, EPA should not finalize the CEMS requirement in the Proposed Rule. If EPA does finalize the CEMS requirement, EPA should: (i) carve out units like Colstrip Units 3 and 4 that already have a CAMS plan that utilizes performance indicators and operational parameters to ensure compliance with the particulate standard; and (ii) not require PM CEMS for units that would only be subject to MATS for a limited time after the effective date of the final rule. 1V. CONCLUSION Palen Montana appreciates the opportunity to submit comments on the Proposed Rule. Talen Montana respectfully requests that EPA consider the recommendations above to ensure that the Agency accounts for Colstrip's unique design and circumstances, as well as to account for the prohibitive costs that Colstrip faces if it were forced to comply with the proposed fi'M Colstrip is vital to Montana, and premature retirement could jeopardize Montanans' access to affordable and reliable electricity, especially during extreme weather conditions. Dated: June 23, 2023 Respectfully submitted, Thomas Wcissinger Sr. Director -- Environmental Talen Energy thomas.weissingerLhalenenergy.com 26 Sierra Club FOIA 2025-EPA-04883 ED_018388_00000307-00027 SC_EVERSPLIT0006123