Energy & environment · 02/11/2010

EPA Determines Hayden, Nogales, and Paul Spur/Douglas Nonattainment Areas in Arizona Attained PM 10 Standard by 1994

The US Environmental Protection Agency (EPA) has determined that the Hayden, Nogales, and Paul Spur/Douglas nonattainment areas in Arizona met the National Ambient Air Quality Standard (NAAQS) for particulate matter with an aerodynamic diameter of less than or equal to a nominal ten micrometers (PM 10) by December 31, 1994, and are no longer subject to reclassification as 'serious' nonattainment areas. However, recent ambient monitoring data show that these areas are currently not attaining the PM 10 standard.