The United States Environmental Protection Agency (“EPA”) Region 6 Acting Regional Administrator sent an August 22nd letter to Arkansas Governor Asa Hutchinson providing notification of the federal agency’s:

. . . intended designations for certain areas in Arkansas for the 2010 Primary National Ambient Air Quality Standard (NAAQS) for sulfur dioxide (SO2).

EPA states that the designations are a response to designation-related recommendations and information that Arkansas submitted in letters dated March 22, 2011, and January 24, 2017.

Sections 108 and 109 of the Clean Air Act require EPA to identify air pollutants utilizing certain criteria and set NAAQS. SO2 is one of the air pollutants currently designated as a criteria air pollutant and subject to NAAQS.

After a NAAQS is established, the Clean Air Act requires that EPA designate areas in the United States as attainment, non-attainment, or unclassifiable (insufficient data). States are provided the opportunity to submit recommendations to EPA as to whether or not an area is attaining the NAAQS for a criteria air pollutant. Once a NAAQS is established for an air pollutant, the states are primarily responsible for ensuring its attainment and maintenance.

EPA states it is notifying Arkansas of the agency’s assessment of its recommended designations for all remaining undesignated areas in Arkansas that were not previously designated. It notes agreement with Arkansas’s recommendations for many areas, but states that some areas warrant further discussion.

EPA recommends a designation of unclassifiable/attainment for Benton and Mississippi counties. The agency also states that it intends to designate as unclassifiable/attainment all remaining areas of Arkansas that were not required to be characterized and for which it does not have information suggesting the area may not be meeting the NAAQS or contributing to air quality in a nearby area (that does not meet the NAAQS).

A copy of the August 22nd letter from EPA to the State of Arkansas and the January 24th letter from the State of Arkansas to EPA can be downloaded here.