2025-11825Proposed Rule

EPA Nods to Missouri's SO2 Emission Rule Refresh

Published Date: 6/27/2025

Proposed Rule

Summary

The EPA wants to approve Missouri’s updated plan to control sulfur dioxide pollution, swapping old rules for newer, clearer ones. This update affects power plants and cleans up outdated rules but won’t make pollution limits any easier or harder. No new costs or deadlines for businesses, just a smoother, smarter way to keep Missouri’s air clean.

Analyzed Economic Effects

4 provisions identified: 3 benefits, 1 costs, 0 mixed.

State swaps in Missouri SO2 rule

EPA is proposing to approve Missouri replacing the prior statewide sulfur dioxide (SO2) rule in the State Implementation Plan (SIP) with the newer rule 10 CSR 10-6.261. The change cleans up and clarifies the SIP across Missouri but the EPA says it does not change the stringency of limits or the State’s ability to meet the National Ambient Air Quality Standards (NAAQS).

Outdated SO2 requirements removed

The SIP revisions remove outdated SO2 requirements that applied to facilities that have closed, switched from coal to lower-sulfur fuels, or become subject to more stringent SO2 rules elsewhere in the Missouri SIP. This cleanup removes obsolete obligations from the SIP without changing overall pollution limits.

Reinstatement of SO2 limits at two plants

The SIP revisions reinstate SO2 emission limits for the Ameren-Labadie and Evergy-Hawthorn power plants that had previously been removed. EPA is proposing to approve those reinstated limits as part of the updated Missouri SIP.

Approval of sulfuric acid negative declaration

EPA is proposing to approve Missouri’s negative declaration for sources subject to sulfuric acid production requirements that the Missouri Department of Natural Resources submitted on May 4, 2022. That negative declaration states there are no sources in Missouri subject to those specific sulfuric acid production requirements.

Your PRIA Score

Score Hidden

Personalized for You

How does this regulation affect your finances?

Sign up for a PRIA Policy Scan to see your personalized alignment score for this federal register document and every other regulation we track. We analyze your financial profile against policy provisions to show you exactly what matters to your wallet.

Free to start

Key Dates

Published Date
6/27/2025

Department and Agencies

Department
Independent Agency
Agency
Environmental Protection Agency
Source: View HTML
Back to Federal Register

Take It Personal

Get Your Personalized Policy View

Start a Free Government Policy Watch to see how policy affects your household, then upgrade to PRIA Full Coverage for year-round monitoring.

Already have an account? Sign in