EPA is taking final action to approve a State Implementation Plan (SIP) revision submitted by the State of Colorado on July 31, 2002, for the purpose of redesignating the Lamar, Colorado area from nonattainment to attainment for particulate matter with an aerodynamic diameter less than or equal to a nominal 10 micrometers (PM<INF>10</INF>) under the 1987 standards. The Governor's submittal, among other things, documents that the Lamar area has attained the PM<INF>10</INF> National Ambient Air Quality Standards (NAAQS), requests redesignation to attainment and includes a maintenance plan for the area demonstrating maintenance of the PM<INF>10</INF> NAAQS for ten years. EPA is approving this redesignation request and maintenance plan because Colorado has met the applicable requirements of the Clean Air Act (CAA), as amended. Upon the effective date of this approval, the Lamar area will be designated attainment for the PM<INF>10</INF> NAAQS. This action is being taken under sections 107, 110, and 175A of the Clean Air Act.