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

Kent County, Michigan; Keweenaw County, Michigan; and Lake County, Michigan.  The Kent County Seat is Grand Rapids, Michigan; the Keweenaw County Seat is Eagle River, Michigan; and the Lake County Seat is Baldwin, Michigan.