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  2. Sulfur Dioxide Designations

Technical information supporting the Round 2 SO2 designations

Technical information supporting Round 2 SO2 designations  signed on June 30, 2016

  • Electric Power Plant Sources Exceeding the Emissions Thresholds Established by Court Order (pdf) (312.96 KB)
  • Ambient Air Quality Monitors for SO2 Recording Preliminary Violations of the 2010 Primary Standard (pdf) (38.94 KB)
  • States and Tribes Without Violating Monitors or Electric Power Plant Sources Exceeding the Emissions Thresholds Established by the Court Order (pdf) (83.71 KB)
    States and Tribes Without Violating Monitors or Electric Power Plant Sources Exceeding the Emissions Thresholds Established by the Court Order but that Have a Border Located within 20 Kilometers of a Source in a Neighboring State that Exceeds those Emissions Thresholds
  • Technical Assistance Document: SO2 NAAQS Designations Modeling (pdf) (1.4 MB, August 2016)
  • Technical Assistance Document: SO2 NAAQS Designations Source-Oriented Monitoring (pdf) (3.16 MB)

Sulfur Dioxide Designations

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Last updated on March 26, 2025
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