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Revised Cross-State Air Pollution Rule Update

Proposed Rulemaking

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Rule Summary

On October 15, 2020, EPA proposed the Revised Cross-State Air Pollution Rule (CSAPR) Update in order to fully address 21 states' outstanding interstate pollution transport obligations for the 2008 ozone National Ambient Air Quality Standards (NAAQS). Starting in the 2021 ozone season, the proposed rule would require additional emissions reductions of nitrogen oxides (NOX) from power plants in 12 states, improving air quality for millions of Americans.

EPA held a public hearing on November 12, 2020.  The public comment period for the proposal closed on December 14.

Cross-State Air Pollution Rule RegionsCross-State Air Pollution Rule Regions

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Rule History

October 15, 2020 - Revised Cross-State Air Pollution Rule Update

EPA proposed to issue new or amended Federal Implementation Plans (FIPs) to revise emission budgets in 12 states to address air quality impacts of the interstate transport of ozone air pollution.

Technical Support Documents (TSDs)

Links to the TSDs have been updated to direct users to Users may click here to access the docket on the current (except on Tuesdays and Thursdays when will redirect to

Additional supporting information and data for the listed TSDs are available in the official docket.

Additional Resources

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