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Reviewing National Ambient Air Quality Standards (NAAQS)

Responses to Additional Significant Comments on the 2020 Proposed Action on the Ozone National Ambient Air Quality Standards

This document, together with the final decision notice on the review of the ozone (O3) national ambient air quality standards (NAAQS), present the responses of the EPA to significant public comments received on the 2020 proposed decision (85 FR 49830, August 14, 2020).

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Responses to Significant Comments on 2020 Proposed Decision on the O3 NAAQS (PDF)(54 pp, 740 K, Dec 2020)