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

Harlan County, Nebraska; Hayes County, Nebraska; and Hitchcock County, Nebraska.  The Harlan County Seat is Alma, Nebraska; the Hayes County Seat is Hayes Center, Nebraska; and the Hitchcock County Seat is Trenton, Nebraska.