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 Pike County, Arkansas, and

Poinsett County, Arkansas, give the percentage contributions from specific air pollution sources.  The Pike County Seat is Murfreesboro, Arkansas, and the Poinsett County Seat is Harrisburg, Arkansas.