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Sulfur Dioxide Designations

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Sulfur Dioxide Designations - Guidance and Technical Information

Area Designations for the 2010 Primary Sulfur Dioxide National Ambient Air Quality Standard - Round 3
Updated guidance memorandum providing information on the schedule and process for completing area designations for the 2010 primary SO₂ standard.
Technical information supporting SO₂ designations to be completed by July 2, 2016