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Sulfur Dioxide Designations

SO2 Designations - Round 3 State Recommendations and EPA Responses

In response to court-order, the EPA must complete remaining designations for the 2010 primary 1-hour SO2 standard on a schedule that contains two remaining deadlines. By December 31, 2017, the EPA must designate all remaining areas of the country that did not elect to install new SO2 air quality monitors. 

The recommendations and EPA's responses on this page are for areas that are subject to the Round 3 designations effort.

These documents are provided here in PDF format for INFORMATION PURPOSES ONLY.

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