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 Gilchrist County, Florida, and

Glades County, Florida, give the percentage contributions from specific air pollution sources.  The Gilchrist County Seat is Trenton, Florida, and the Glades County Seat is Moore Haven, Florida.