Abstract: The Environmental Protection Agency (EPA) compiles data on emission tonnages of air pollutants for US counties.  US Air Quality Gradebook ("AirGrades") source sheets give the percentage contributions from specific air pollution sources.  This source sheet is for

Brazos County, Texas; Brewster County, Texas; and Briscoe County, Texas.  The Brazos County Seat is Bryan, Texas; the Brewster County Seat is Alpine, Texas; and the Briscoe County Seat is Silverton, Texas.