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Sulfur Dioxide Designations

Reconsideration Requests for Areas in Illinois, Missouri, and Ohio

EPA is responding to three petitions requesting the Agency to reconsider certain area designations for the 2010 health based sulfur dioxide air quality standard. 

After carefully reviewing a petition from Southern Illinois Power Cooperative, EPA is denying their request to reconsider the “nonattainment” designation for Williamson County, Illinois. 

Sierra Club submitted two petitions requesting that EPA reconsider “unclassifiable” designations for
  • portions of Franklin and St. Charles Counties, Missouri including the Ameren Labadie Energy Center and,
  • the Gallia, Ohio Area, including the General James M Gavin Power Plant. 

EPA is granting the Sierra Club petitions and will reconsider these designations during the final round of 2010 sulfur dioxide area designations to be completed by December 31, 2020.

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