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EPA Proposes Revised Cross-State Air Pollution Rule Update for 2008 Ozone NAAQS

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EPA Press Office (

WASHINGTON (October 15, 2020) — Today, the U.S. Environmental Protection Agency (EPA) is proposing revisions to the Cross-State Air Pollution Rule (CSAPR) Update to address interstate air quality impacts for the 2008 ozone air quality standards. The proposed revision would reduce summertime emissions of nitrogen oxides (NOx) from power plants in 12 states that contribute to downwind ozone problems, improving air quality for millions of Americans.

“With this proposal, the Trump Administration is demonstrating once again its commitment to improving air quality across the nation,” said EPA Administrator Andrew Wheeler. “This update to the Cross-State Air Pollution Rule will alleviate interstate air pollution and improve quality of life for many Americans.”

The proposal responds to the September 2019 ruling by the U.S. Court of Appeals for the D.C. Circuit (Wisconsin v. EPA) by addressing the “significant contribution” of pollution that some states make to downwind states to help them meet and maintain compliance with the 2008 ozone standard.

Additional emissions reductions would be required at power plants in 12 states based on optimization of existing controls for the 2021 ozone season and installation or upgrade of low NOX burners for the 2022 ozone season. The proposed cuts in NOx emissions would lead to significant improvements in air quality beginning in the 2021 ozone season.

EPA estimates that the Revised CSAPR Update proposal would reduce NOx emissions from power plants in 12 states in the eastern United States by 17,000 tons in 2021 compared to projections without the rule. Due to this proposed rule and other changes already underway in the power sector, ozone season NOx emissions in these 12 states would be nearly 26,000 tons lower in 2021 than in 2019, a reduction of nearly 20 percent.

EPA will accept comments for 45 days after publication in the Federal Register and will hold a virtual public hearing two weeks after publication.

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