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Ground-level Ozone Pollution

Procedures for Processing Requests to Redesignate Areas to Attainment

This memorandum consolidates EPA's guidance regarding the processing of requests for redesignation of nonattainment areas to attainment for ozone (O3), carbon monoxide (CO), particulate matter (PM), sulfur dioxide (SO2), nitrogen dioxide (NO2), and lead (Pb). Regional offices should use this guidance as a general framework for drafting Federal Register notices pertaining to redesignation requests.

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