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  2. 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).
 
Read the Federal Register Notice: Air Quality Designations for the 2010 Sulfur Dioxide (SO2) Primary National Ambient Air Quality Standard - Round 3 - Supplemental Amendment (pdf) (257 KB)
  • Fact Sheet for Final SO2 Designations Round 3 Citrus County Amendment (pdf) (424.07 KB)
  • Updated Table of Sulfur Dioxide Round 3 Area Designations Completed in December 2017 (pdf) (400.44 KB)

Sulfur Dioxide Designations

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Last updated on May 7, 2025
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