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 Sangamon County, Illinois, and

Schuyler County, Illinois, give the percentage contributions from specific air pollution sources.  The Sangamon County Seat is Springfield, Illinois, and the Schuyler County Seat is Rushville, Illinois.