Policy and Guidance
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EPA Issues Guidance for Designating Areas for the Sulfur Dioxide Primary National Air Quality Standard
March 24, 2011 - The Environmental Protection Agency issued guidance on the schedule and process for designating areas for the 2010 revised primary sulfur dioxide (SO2) NAAQS. The document also includes guidance on conducting air quality modeling to inform SO2 designation decisions.
- Guidance Memorandum (PDF) (42pp, 12.0 MB) - Updated April 11, 2011