Approval and Promulgation of Air Quality Implementation Plan; State of Colorado Second Ten-Year PM10 Maintenance Plan for Telluride

The Environmental Protection Agency (EPA) is taking final action approving State Implementation Plan (SIP) revisions submitted by the State of Colorado. On March 31, 2010, the designee of the Governor of Colorado submitted to EPA a revised maintenance plan for the Telluride area for the 24-hour National Ambient Air Quality Standards (NAAQS) for particulate matter with an aerodynamic diameter less than or equal to 10 microns (PM<INF>10</INF>), and the SIP was adopted on November 19, 2009. As required by Clean Air Act (CAA) section 175A, this revised maintenance plan addresses maintenance of the PM<INF>10</INF> standard for a second 10-year period beyond the area's original redesignation to attainment for the PM<INF>10</INF> NAAQS. In addition, EPA is taking final action approving the revised maintenance plan's 2021 transportation conformity motor vehicle emissions budget for PM<INF>10.</INF> Also, we are taking final action to exclude exceedances of the PM<INF>10</INF> NAAQS that were recorded at the Telluride PM<INF>10</INF> monitor on April 5, 2010 and April 16, 2013, from use in determining whether or not Telluride continues to attain the PM<INF>10</INF> NAAQS, because they meet the criteria for exceptional events caused by high wind natural events. This action is being taken under sections 110 and 175A of the CAA.