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Sulfur Dioxide Designations

EPA Completes Second Round of Sulfur Dioxide Designations

June 30, 2016 - After reviewing all available data and information, EPA is completing a second round of area designations.   As described in the preamble to EPA’s SO2 Data Requirements Rule, the EPA will designate all remaining areas by either December 31, 2017, or December 31, 2020.

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