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PM2.5 Clean Data Policy Clarification Memorandum

This memorandum issued on May 22, 2008, to EPA's Regional Air Division Directors, provides clarification regarding language in the preamble of EPA's particulate matter (PM2.5) implementation rule (April 25, 2007) as it relates to EPA's Clean Data Policy.

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Memorandum: PM2.5 Clean Data Policy Clarification (PDF)(3 pp, 150 K, May 22, 2008)