Approval and Promulgation of Air Quality Implementation Plans; State of Colorado; Denver Carbon Monoxide Redesignation to Attainment, Designation of Areas for Air Quality Planning Purposes, and Approval of Related Revisions

On August 22, 2001, EPA published a notice of proposed rulemaking (NPR) to propose approval of the State of Colorado's request to redesignate the Denver-Boulder metropolitan (hereafter, Denver) "serious" carbon monoxide (CO) nonattainment area to attainment for the CO National Ambient Air Quality Standard (NAAQS). In that NPR, EPA proposed to approve the CO maintenance plan for the Denver area and the additional State Implementation Plan elements involving revisions to Colorado's Regulation No. 11 "Motor Vehicle Emissions Inspection Program", Colorado's Regulation No. 13 "Oxygenated Fuels Program", and the Governor's May 7, 2001, submittal of a SIP revision ("United States Postal Service (USPS) revision") that is intended to be a substitute for a Clean Fuel Fleet Program. In this action, EPA is approving the Denver CO redesignation request, the maintenance plan, the revisions to Regulation No. 11 and Regulation No. 13, the USPS revision and the CO transportation conformity budgets.