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Sulfur Dioxide Designations

SO2 Designations - Round 2 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 three specific deadlines. By July 2, 2016, the EPA must designate two groups of areas (Round 2):

  1. areas with newly monitored violations of the 2010 primary 1-hour SO2  standard, and
  2. areas containing stationary sources that had not been announced as of March 2, 2015 for retirement and that according to the EPA’s Air Markets Database emitted in 2012 either (i) more than 16,000 tons of SO2 or (ii) more than 2,600 tons of SO2 with an annual average emission rate of at least 0.45 pounds of SO2 per one million British thermal units (lbs SO2/mmBTU).

On March 20, 2015, the EPA provided guidance and data to states directly impacted by Round 2 of the 2010 primary 1-hour SO2 standard designation process. The EPA also notified states and tribes without violating monitors or sources exceeding the emissions threshold 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.

The recommendations and EPA's responses on this page are for areas that are subject to the Round 2 designations effort.

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

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