2006 PM-2.5 Nonattainment Areas
This data layer identifies areas in the U.S. where air pollution levels have not met the National Ambient Air Quality Standards (NAAQS) for 2006 PM-2.5 standards. These areas were designated "nonattainment" on October 8, 2009. The designations were published in the Federal Register on November 13, 2009. See 74 FR …