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.

• Procedures for Processing Requests to Redesignate Areas to Attainment, Calcagni 9/4/92 memo (PDF)(13 pp, 607 K, September 4, 1992)
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