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 Monongalia County, West Virginia, and

Monroe County, West Virginia, give the percentage contributions from specific air pollution sources.  The Monongalia County Seat is Morgantown, West Virginia, and the Monroe County Seat is Union, West Virginia.