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Reviewing National Ambient Air Quality Standards (NAAQS)

Responses to Significant Comments on the 2020 Proposed Decision on the National Ambient Air Quality Standards for Particulate Matter

This document, together with the final decision notice on the review of the national ambient air quality standards for particulate matter, presents the responses of the EPA to significant public comments received on the 2020 proposed decision (85 FR 24094, June 29, 2020).

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Responses to Significant Comments on the 2020 Proposed Decision on the National Ambient Air Quality Standards for Particulate Matter (PDF)(57 pp, 425 K, December 2020)