EPA is clarifying and correcting the tables in the Code of Federal Regulations that identify the Agency's designations and classifications of nonattainment, attainment, and unclassifiable areas for criteria pollutants within the State of Nevada. Specifically, EPA is clarifying the tables for Nevada to indicate the specific geographic areas that comprise the attainment and unclassifiable areas in the State and to reflect changes in the Agency's regulations implementing the prevention of significant deterioration program. EPA is also correcting the table that shows the classification of the Las Vegas Valley nonattainment area for the National Ambient Air Quality Standard for carbon monoxide.