Air Quality Designations for the 2010 Sulfur Dioxide (SO2

This final rule establishes the initial air quality designations for certain areas in the United States (U.S.) for the 2010 sulfur dioxide (SO2) primary National Ambient Air Quality Standard (NAAQS). The Environmental Protection Agency (EPA) is designating the areas as either Nonattainment, Attainment/ Unclassifiable, or Unclassifiable. The designations are based on application of the EPA's nationwide analytical approach and technical analysis, including evaluation of monitoring data and air quality modeling, to determine the appropriate designation based on the weight of evidence for each area. The Clean Air Act (CAA or Act) directs areas designated Nonattainment by this rule to undertake certain planning and pollution control activities to attain the SO2 NAAQS as expeditiously as practicable. This is the third of four expected sets of actions to designate areas of the U.S. for the 2010 SO2 NAAQS.