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 Pershing County, Nevada, and

Storey County, Nevada, give the percentage contributions from specific air pollution sources.  The Pershing County Seat is Lovelock, Nevada, and the Storey County Seat is Virginia City, Nevada.