Missouri Dumps Old Power Plant Pollution Rules, EPA OKs
Published Date: 4/29/2025
Proposed Rule
Summary
The EPA is proposing to approve Missouri’s request to remove two old rules that controlled nitrogen oxide (NOX) emissions from power plants. These rules are already phased out and taking them off won’t hurt air quality. This change affects power plants in Missouri and has no new costs or deadlines, but comments are open until May 29, 2025.
Analyzed Economic Effects
2 provisions identified: 1 benefits, 1 costs, 0 mixed.
Gap: No Enforceable NOX Mass Limits for Large Non-EGUs
The EPA states that, since it stopped administering the CAIR OS trading program after the 2014 ozone season, Missouri currently lacks enforceable seasonal NOX mass emissions limits for existing and new large non-electric-generating units (large non-EGUs) in the eastern one-third of the State. The EPA notes Missouri does not have SIP provisions meeting the requirements of 40 CFR 51.121(f)(2) and (r)(2) for those large non-EGUs and says the issue is beyond the scope of this removal action, while offering to assist Missouri in remedying the gap.
Remove Obsolete NOX Rules
If you operate a power plant in Missouri, the EPA proposes to remove two state rules (10 CSR 10-6.360 and 10 CSR 10-6.350) from the Missouri State Implementation Plan. These rules were sunsetted after the 2008 ozone season, the State requested removal on November 14, 2018, and the EPA says removing them will not affect air quality and will not create new costs or deadlines.
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