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 Rio Arriba County, New Mexico, and

Roosevelt County, New Mexico, give the percentage contributions from specific air pollution sources.  The Rio Arriba County Seat is Tierra Amarilla, New Mexico, and the Roosevelt County Seat is Portales, New Mexico.