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 Scott County, Tennessee, and

Sequatchie County, Tennessee, give the percentage contributions from specific air pollution sources.  The Scott County Seat is Huntsville, Tennessee, and the Sequatchie County Seat is Dunlap, Tennessee.