Document n99Nq5NQMwxRKvvqaJVryoe3z

USSOA02see##241-1280 Ciaoouratatit206636@3 FFfildc1006/2Y22024 PIgge454 of @28 that States must use when setting COE emissions limits for such units. 89 Fed. Reg. at 39,840. Under the provisions of the Rule, Colstrip Units 3 and 4 have three options: (1) retire by .lanuary 1, 2032; (2) meet an emission rate based on 40% natural gas co-firing by .lanuary 1, 2030, and retire by January 1, 2039; and (3) install and operate 90% efficient carbon capture and storage ("CCS") by January 1, 2032, which would allow the unit to operate after 2038. Based on Talen's assessment, the only compliance strategy available for Colstrip consists of shutting down the plant by January 1, 2032. 9. The CCS BSER established by the Final Rule for existing coal-fired steam units is not yet adequately demonstrated, is not achievable, and is not cost-effective. Further, EPA has established deadlines for incorporating this technology, or in the alternative gas co-firing, that are so unreasonable that they likely cannot be met--even if the technologies were adequately demonstrated and achievable. The end result is that owners and operators will have little choice but to retire such units prematurely. IMPACT OF TIIE FINAL RULE ON COLSTRIP 10. The Rule requires major modifications to Colstrip Units 3 and 4 or premature retirement of the Units. Specifically, a decision must be made immediately between the three possible compliance choices (retire by 2032, co-fire gas by 2030, or install full CCS by 2032) in order to complete any retrofits in time for the Rule's compliance deadlines. Prematurely shutting down Colstrip would have significant economic impacts on Montana and beyond and raises serious concerns about grid reliability and transmission. 4 Sierra Club FOIA 2025-EPA-04883 ED_018388_00000309-00054 SC_EVERSPLIT0006217