Air Plan Disapproval; Missouri; Control of Sulfur Dioxide Emissions

The Environmental Protection Agency (EPA) is taking final action to disapprove revisions to the Missouri State Implementation Plan (SIP) submitted by Missouri on March 7, 2019. In its submission, Missouri requested rescinding a regulation addressing sulfur compounds from the SIP and replacing it with a new regulation that establishes requirements for units emitting sulfur dioxide (SO<INF>2</INF>). The EPA is disapproving the SIP revision because the state has not demonstrated that the removal of SO<INF>2</INF> emission limits for the Evergy-Hawthorn (Hawthorn, formerly Kansas City Power & Light-Hawthorn) and Ameren Labadie (Labadie) power plants from the SIP would not interfere with National Ambient Air Quality Standard (NAAQS) attainment and reasonable further progress (RFP), or any other applicable requirement of the Clean Air Act (CAA). This disapproval action is being taken under the CAA to maintain the stringency of the SIP and preserve air quality.