Clarksville, TN – A federal grant will help Clarksville produce biodiesel for the city utilities department and city transit buses. The 45-thousand dollar grant will purchase a machine that processes used cooking oil to mix with diesel fuel. Transportation planner Jill Hall says the device produces almost a gallon of biodiesel for every gallon of cooking oil at a cost of about $1 per gallon. Hall tells The Leaf-Chronicle benefits include improving air quality and diverting grease that would otherwise flow into the city's sewer system. City wastewater manager David Hoffman says the city has identified 1,300 gallons of cooking oil it can collect weekly from 95 restaurants and more is likely. An air quality grant made the purchase possible and more of the machines may be bought.