Approval of Missouri Air Quality Implementation Plans; Redesignation of the Missouri Portion of the St. Louis-St. Charles-Farmington, MO-IL 2008 Ozone Area to Attainment

The Environmental Protection Agency (EPA) is taking final action to redesignate the Missouri portion of the St. Louis-St. Charles-Farmington, MO-IL nonattainment area (``St. Louis area'' or ``area'') to attainment for the 2008 ozone National Ambient Air Quality Standard (NAAQS). EPA is also approving, as a revision to the Missouri State Implementation Plan (SIP), the state's plan for maintaining the 2008 8-hour ozone NAAQS through 2030. Finally, EPA finds adequate and is approving, as a SIP revision, the State's 2030 volatile organic compound (VOC) and oxides of nitrogen (NOX) Motor Vehicle Emission Budgets (MVEBs) for the Missouri portion of the St. Louis area. The Missouri Department of Natural Resources (MDNR) submitted this request on September 12, 2016, with a supplemental submission on February 16, 2018. EPA addressed the Illinois portion of the St. Louis area in a separate rulemaking action published in the Federal Register on March 1, 2018.