Abstract: The Environmental Protection Agency (EPA) compiles data on emission tonnages of air pollutants for US counties.  US Air Quality Gradebook ("AirGrades") source sheets give the percentage contributions from specific air pollution sources.  This source sheet is for

Maricopa County, Arizona; Mohave County, Arizona; and Navajo County, Arizona.  The Maricopa County Seat is Phoenix, Arizona; the Mohave County Seat is Kingman, Arizona; and the Navajo County Seat is Holbrook, Arizona.