EPA is taking final action to approve a revised attainment plan, as modified to withdraw the motor vehicle emissions budget for 2030, for the Las Vegas Valley carbon monoxide nonattainment area as a revision to the Nevada state implementation plan. The revised attainment plan, as modified, includes revised base year and future year emissions inventories and a revised demonstration of continued attainment of the carbon monoxide national ambient air quality standard in Las Vegas Valley through 2020 based on the most recent emissions models and planning assumptions and establishes new motor vehicle emissions budgets. EPA is acting under section 110(k) of the Clean Air Act, which obligates the Agency to take action on State submittals of revisions to state implementation plans. The intended effect of this approval action is to update the carbon monoxide motor vehicle emissions budgets in the Las Vegas area and thereby make them available for the purposes of transportation conformity.