The EPA is granting a deferral of the effective date, to September 13, 2004, of the 8-hour ozone nonattainment designation for Clark County, Nevada. This deferral is based on additional information submitted by the State demonstrating that, due to the late finding of nonattainment in the State, the State did not have sufficient time to recommend an appropriate boundary for the Las Vegas nonattainment area. EPA believes the relevant factors for defining a nonattainment area may support a different boundary recommendation than the one submitted by the State on April 12, 2004, and a short deferral will provide the State and EPA time to determine whether such an adjustment is appropriate. At the same time, it is certain that at least some portion of Clark County will be designated nonattainment. As such, we do not intend to use this extension of the effective date of the designation to affect the deadline for submittal of the State implementation plan that would otherwise apply if the effective date were not deferred and further believe the extension should not delay attainment of the ozone standard or the ability of the State to achieve attainment as expeditiously as practicable.