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Sulfur Dioxide Designations

Recommendations for Areas to be Designated Nonattainment for the 2010 National Air Quality Standard for Sulfur Dioxide

February 7, 2013 – In response to recommendations from state and tribal representatives, EPA sent letters to state and tribal leaders outlining the areas it is considering designating as “nonattainment” for the 2010 primary standard for sulfur dioxide. 

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