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 Honolulu County, Hawaii, and

Kalawao County, Hawaii, give the percentage contributions from specific air pollution sources.  The Honolulu County Seat is Honolulu, Hawaii, and the Kalawao County Seat is Kalaupapa, Hawaii.