Approval and Promulgation of Air Quality Implementation Plans; Colorado; Designation of Areas for Air Quality Planning Purposes, Steamboat Springs

EPA is taking final rule 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 Steamboat Springs, 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 Steamboat Springs 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. On August 5, 2004, EPA proposed to approve (69 FR 47399) in parallel with a direct final rule (69 FR 47366) Colorado's Steamboat Springs submittal in conjunction with Colorado's submittal to redesignate Lamar, Colorado. However, adverse comments pertaining to the Lamar PM<INF>10</INF> redesignation were received during the public comment period, therefore, EPA withdrew the approval of Lamar and Steamboat Springs. Since no comments were received during the public comment period on the approval of redesignating Steamboat Springs, EPA is acting to approve the redesignation in this final rule. EPA is approving this redesignation request and maintenance plan for Steamboat Springs because Colorado has met the applicable requirements of the Clean Air Act (CAA), as amended. Upon the effective date of this approval, the Steamboat Springs 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.