EPA is disapproving the State Implementation Plan (SIP) submitted by the State of Montana to demonstrate that the SIP meets one of the infrastructure requirements of the Clean Air Act (CAA) for the National Ambient Air Quality Standards (NAAQS) promulgated for ozone on July 18, 1997. The CAA requires that each state, after a new or revised NAAQS is promulgated, review their SIPs to ensure that they meet infrastructure requirements. The State of Montana submitted certifications of their infrastructure SIP for the 1997 ozone NAAQS on November 28, 2007 and December 22, 2009. EPA is disapproving Montana's submissions with respect to the infrastructure element regarding state boards.