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Sulfur Dioxide Designations

EPA Supplemental Amendment for the Third Round of SO2 Area Designations

On March 28, 2018, the U.S. Environmental Protection Agency (EPA) withdrew the designation of Unclassifiable for the Citrus County, Florida, area that the EPA originally issued on December 21, 2017, and established a designation of Attainment/Unclassifiable for that area as part of promulgating 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).
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