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 Bullitt County, Kentucky, and

Butler County, Kentucky, give the percentage contributions from specific air pollution sources.  The Bullitt County Seat is Shepherdsville, Kentucky, and the Butler County Seat is Morgantown, Kentucky.