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.

• Proposed Rule

• Fact Sheet: Proposed Attainment Determinations (PDF)(3 pp, 98 K)