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  2. Ground-level Ozone Pollution

Final Determinations of Attainment by the Attainment Date, Extensions of the Attainment Date, and Reclassification of Several Areas Classified as Marginal for the 2015 Ozone Air Quality Standards

As required by the Clean Air Act, EPA  finalized actions for 28 nonattainment areas classified as Marginal for the 2015 ozone National Ambient Air Quality Standards (NAAQS). These areas were required to attain the standards by August 3, 2021.

This rulemaking will ensure that smog-affected communities achieve healthy air and implement the measures that the Clean Air Act requires to protect public health in these areas.  

EPA based these determinations on ozone monitoring data, from the years 2018 - 2020.  Read the final rule and a summary fact sheet below. 

Final Rule: Determinations of Attainment by the Attainment Date, Extensions of the Attainment Date, and Reclassification of Areas Classified as Marginal for the 2015 Ozone National Ambient Air Quality Standards (pdf) (499 KB)

Fact Sheet: Final Determinations of Attainment by the Attainment Date, Extension of the Attainment Date, and Reclassification of Several Areas Classified as Marginal for the 2015 Ozone National Ambient Air Quality Standards (pdf) (155.23 KB, 9.16.22)

Ground-level Ozone Pollution

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Contact Us About Ozone Pollution
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Last updated on May 1, 2025
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