An official website of the United States government.

This is not the current EPA website. To navigate to the current EPA website, please go to This website is historical material reflecting the EPA website as it existed on January 19, 2021. This website is no longer updated and links to external websites and some internal pages may not work. More information »

Sulfur Dioxide (SO2) Pollution

SO2 Data Requirements Rule: Source Lists

The SO2 Data Requirements Rule (DRR) requires that air agencies identify and characterize air quality around large sources of SO2.  By January 15, 2016, air agencies were required to submit to EPA a list of sources that emit 2,000 tons per year (tpy) or more of SO2, based on the most recently available data.

Below are links to state submittals to meet the DRR source list requirement and EPA response documents. 

  • Region 1 (Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island, Vermont)
  • Region 2 (New Jersey, New York, Puerto Rico)
  • Region 3 (Delaware, District of Columbia, Maryland, Pennsylvania, Virginia, West Virginia)
  • Region 4 (Alabama, Florida, Georgia, Kentucky, Mississippi, North Carolina, South Carolina, Tennessee)
  • Region 5 (Illinois, Indiana, Michigan, Minnesota, Ohio, Wisconsin)
  • Region 6 (Arkansas, Louisiana, New Mexico, Oklahoma, Texas)
  • Region 7 (Iowa, Kansas, Missouri, Nebraska)
  • Region 8 (Colorado, Montana, North Dakota, South Dakota, Utah, Wyoming)
  • Region 9 (Arizona, California, Hawaii, Nevada, Pacific Islands)
  • Region 10 (Alaska, Idaho, Oregon, Washington)

The source list below includes SO2 sources to be addressed under the Data Requirements Rule, including sources listed by the state or tribe and sources listed by EPA. This list was posted on April 13, 2016, and was amended on May 24, 2016 to remove a source in the state of Texas, and was amended on June 28, 2016 to remove two sources in the state of Minnesota. 

You may need a PDF reader to view some of the files on this page. See EPA’s About PDF page to learn more.