Updates to the Sulfur Dioxide (SO2) National Ambient Air Quality Standard (NAAQS) Area Attainment Designation Recommendation for Counties in the State of Arkansas

Section 107(d)(1) of the Federal Clean Air Act requires state governors to recommend attainment status designations upon promulgation of any new or revised NAAQS. As part of the implementation of the new 1-hour SO2 NAAQS, EPA has begun requiring, in addition to monitoring data, the use of dispersion modeling for areas with facilities emitting large quantities of SO2 as a means of determining compliance with the new standard. Currently, only two counties in Arkansas fall under this requirement: Independence and Jefferson. On September 14, 2015, Arkansas Governor, Asa Hutchinson submitted a letter to the Environmental Protection Agency (EPA) asserting that it is the State’s recommendation that: 1) the two counties with existing monitor sites, Pulaski and Union, should be designated “attainment”, 2) that based on the information contained in the enclosed dispersion modeling reports, Independence and Jefferson counties should be designated “unclassifiable/attainment”, and that 3) all other counties in Arkansas should be designated “unclassifiable”.

• Arkansas Governor, Asa Hutchinson, Recommendation Letter
• Entergy Arkansas Inc.’s Independence Steam Electric Station SO2 Air Dispersion Modeling Report
• Entergy Arkansas Inc.’s White Bluff Steam Electric Station SO2 Air Dispersion Modeling Report