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 Sherman County, Oregon, and

Tillamook County, Oregon, give the percentage contributions from specific air pollution sources.  The Sherman County Seat is Moro, Oregon, and the Tillamook County Seat is Tillamook, Oregon.