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Particulate Matter (PM) Pollution

Proposed Determinations of Attainment, Failure to Attain and Reclassifications for the 2006 24-Hour PM Standards

On December 1, 2016 , the U.S. Environmental Protection Agency proposed determinations for 11 nonattainment areas classified as Moderate for the 2006 24-Hour Fine Particulate Matter National Ambient Air Quality Standards.  Based on requirements under the Clean Air Act, these areas were required to meet the standard by December 31, 2015.

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