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 Sauk County, Wisconsin, and

Sawyer County, Wisconsin, give the percentage contributions from specific air pollution sources.  The Sauk County Seat is Baraboo, Wisconsin, and the Sawyer County Seat is Hayward, Wisconsin.