Sulfur Dioxide (SO2) Designations Round 4: Illinois State Recommendation and EPA Response

Read the Illinois recommendation for Round 4 area designations and EPA's response.

• Round 4 State Recommendation (pdf) (1,956 KB)
• EPA Response to Round 4 Recommendation (pdf) (180 KB)
• Technical Support Documents
  • Chapter 1: Background and History of the Intended Round 4 Area Designations for the 2010 1-Hour SO2 Primary National Ambient Air Quality Standard (pdf) (186 KB)
  • Chapter 2: Intended Round 4 Area Designations for the 2010 1-Hour SO2 Primary National Ambient Air Quality Standard for Areas without Violating Monitors (pdf) (306 KB)