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 Saline County, Missouri, and

Schuyler County, Missouri, give the percentage contributions from specific air pollution sources.  The Saline County Seat is Marshall, Missouri, and the Schuyler County Seat is Lancaster, Missouri.