The U.S. Environmental Protection Agency (EPA) is taking final action to find that three states have failed to submit timely revisions to their state implementation plans (SIPs) as required to satisfy certain requirements under the Clean Air Act (CAA) for implementation of the 2008 ozone National Ambient Air Quality Standards (2008 ozone NAAQS). These findings of failure to submit apply to states with overdue SIP revisions (or attainment plans) for nonattainment areas reclassified from "Marginal" to "Moderate" in May 2016 because the areas failed to attain the 2008 ozone NAAQS by the Marginal area attainment date of July 20, 2015. The SIP revisions to address all applicable Moderate area attainment plan requirements for these areas were due on January 1, 2017. This action requires the affected states to timely submit a SIP revision consistent with the requirements of the CAA and the EPA regulations. If a state fails to make the required timely SIP submittal, or if a submitted SIP is incomplete, the CAA requires the imposition of sanctions for the affected area(s). In addition, the EPA is obligated to promulgate a federal implementation plan (FIP) to address any outstanding SIP requirements if a state does not submit, and the EPA does not approve, a state's submittal within 24 months of the effective date of these findings.