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Sulfur Dioxide (SO2) Pollution

SO2 Data Requirements Rule: January 13, 2017 State Submittals

Under the SO2 Data Requirements Rule (DRR), air agencies were required by January 13, 2017 to submit the following information for SO2 sources subject to the DRR:

  • modeling for those sources being characterized by modeling to meet the DRR; 
  • documentation for those sources that chose to take federally enforceable emission limits to reduce emissions below 2,000 tons per year (tpy); or,
  • documentation that demonstrates that a source has shut down by January 13, 2017.

A summary table of state notification letters regarding the DRR pathway notification requirement, receipt of DRR modeling, emissions limit, and shut down state submissions, and information received from states on monitoring as of March 2017 is available on the SO2 Data Requirements Rule: State Pathway Notifications page. The summary table reflects receipt of information and does not indicate completeness or technical adequacy of the regulating agency's submittal.

The drop-down menu below provides links to the documents submitted by states to meet these requirements.

After you select a state, press "go" to access the documents submitted by that state.

Contact Information:
For questions concerning a state’s submittal, or to obtain the full input and output modeling files submitted to EPA, please contact the respective EPA regional office. Information on the regional modeling contacts is available through the following link: