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Particulate Matter (PM) Pollution

DC Circuit Decision of Fine Particle National Ambient Air Quality Standards (NAAQS) Implementation Rule and New Source Review (NSR)/Prevention of Significant Deterioration Rule (Natural Resources Defense Council v. EPA)

The January 4, 2013, decision from the DC Circuit which held that the EPA should have issued its 2007 PM2.5 National Ambient Air Quality Standards (NAAQS) Implementation Rule and the related 2008 New Source Review (NSR)/Prevention of Significant Deterioration (PSD) rule for the 1997 PM2.5 NAAQS according to the Clean Air Act requirements for PM10 nonattainment areas (Title I, Part D, subpart 4), not the general requirements for nonattainment areas (subpart 1).

For more information on the rule please go to Implementation of the 2006 Particulate Matter (PM) National Ambient Air Quality Standards (NAAQS).

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