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Updated Guidance for Sulfur Dioxide Area Designations - March 2015

This updated guidance memorandum provides information on the schedule and process for completing area designations for the 2010 primary SO2 standard.

Updated Guidance for Sulfur Dioxide Area Designations (pdf) (1.21 MB, March 20, 2015)

Updated Guidance for Sulfur Dioxide Area Designations - March 2015

Sulfur Dioxide Designations