40 C.F.R. § 81.40
The Metropolitan San Antonio Intrastate Air Quality Control Region (Texas) has been revised to consist of the territorial area encompassed by the boundaries of the following jurisdictions or described area (including the territorial area of all municipalities (as defined in section 302(f) of the Clean Air Act, 42 U.S.C. 1857h(f) ) geographically located within the outermost boundaries of the area so delimited):
In the State of Texas: Atascosa County, Bandera County, Bexar County, Comal County, Dimmit County, Edwards County, Frio County, Gillespie County, Guadalupe County, Karnes County, Kendall County, Kerr County, Kinney County, La Salle County, Maverick County, Medina County, Real County, Uvalde County, Val Verde County, Wilson County, Zavala County.
40 C.F.R. §81.40