The Environmental Protection Agency (EPA) is establishing initial air quality designations for the eight counties in the San Antonio-New Braunfels, Texas Core Based Statistical Area (CBSA) for the 2015 primary and secondary national ambient air quality standards (NAAQS) for ozone. The EPA is designating Bexar County as the San Antonio, Texas nonattainment area and the remaining seven counties as attainment/unclassifiable areas. The San Antonio, Texas nonattainment area is also being classified as Marginal by operation of law according to the severity of its air quality problem. Of the five classification categories, Marginal nonattainment areas have ozone levels that are closest to the ozone NAAQS at the time of designation. This action completes the initial designations for the 2015 ozone NAAQS. The EPA designated all other areas of the country for the 2015 ozone NAAQS in actions signed by the Administrator on November 6, 2017, and April 30, 2018.