The Environmental Protection Agency (EPA, or Agency) is denying the petitions to reconsider the final revised primary national ambient air quality standard (NAAQS) for oxides of sulfur as measured by sulfur dioxide (SO<INF>2</INF>) issued under section 109 of the Clean Air Act (CAA). The final revised SO<INF>2</INF> Primary NAAQS was published on June 22, 2010, and became effective on August 23, 2010. EPA has carefully reviewed all of the petitions and revisited both the rulemaking record and the Administrator's decision process underlying the final revised SO<INF>2</INF> Primary NAAQS in light of these petitions. EPA's analysis of the petitions reveals that the petitions have provided inadequate and generally irrelevant arguments and evidence that the underlying information supporting the final revised SO<INF>2</INF> Primary NAAQS is flawed, misinterpreted or inappropriately applied by EPA. The petitioners' arguments fail to meet the criteria for reconsideration under the Clean Air Act.