Approval and Promulgation of Implementation Plans; Missouri; Interstate Transport of Pollution

EPA is revising the Missouri State Implementation Plan (SIP) for the purpose of approving the Missouri Department of Natural Resources' (MDNR) actions to address requirements of section 110(a)(2)(D)(i) of the Clean Air Act. Section 110(a)(2)(D)(i) requires each state to submit a SIP that prohibits emissions that adversely affect another state's air quality through interstate transport. MDNR has adequately addressed the four distinct elements related to the impact of interstate transport of air pollutants. These include prohibiting significant contribution to downwind nonattainment of the National Ambient Air Quality Standards (NAAQS), interference with maintenance of the NAAQS, interference with plans in another state to prevent significant deterioration of air quality, and interference with efforts of other states to protect visibility. The requirements for public notification were also met by MDNR.