Approval and Promulgation of Air Quality Implementation Plans; State of Utah; Utah County PM10 State Implementation Plan Revisions

EPA is finalizing approval of the State of Utah's revision to the Utah State Implementation Plan (SIP) that was submitted by the Governor on July 3, 2002, revising the SIP for the Utah County nonattainment area for particulates of 10 microns in size or smaller (PM<INF>10</INF>). The Governor's submittal, among other things, revises the existing attainment demonstration in the approved PM<INF>10</INF> SIP based on a short-term emissions inventory, establishes 24-hour emission limits for the major stationary sources in the Utah County PM<INF>10</INF> nonattainment area and establishes motor vehicle emission budgets based on EPA's most recent mobile source emissions model, Mobile6. On September 10, 2002 EPA published a notice of proposed rulemaking (NPR) (67 FR 57357). EPA's comment period concluded on October 10, 2002. During this comment period, EPA received ten letters from various local governments within the Utah County area supporting EPA's approval of this SIP revision and two letters with specific comments regarding the approval of this action. The comments received and EPA's responses are addressed below. In this final rule action, EPA approves the Governor's July 3, 2002 submittal adopting rule R307-110-10 which incorporates revisions to portions of Utah's SIP Section IX, Part A and rule R307-110-17 which incorporates revisions to portions of Utah's SIP Section IX, Part H. This action is being taken under sections 107, 110, and 189 of the Clean Air Act (Act).