Abstract: The Environmental Protection Agency (EPA) compiles data on emission tonnages of air pollutants for US counties.  US Air Quality Gradebook ("AirGrades") source sheets such as this one for Jefferson County, Texas, and

Jim Hogg County, Texas, give the percentage contributions from specific air pollution sources.  The Jefferson County Seat is Beaumont, Texas, and the Jim Hogg County Seat is Hebbronville, Texas.