A tire dump in Pettis County, estimated to contain 80,000 tires, is being cleaned up by minimum-security inmates – part of a program that has recycled 2.3-Million tires in the past seven years. Department of Corrections spokesman Tim Kniest says the Department of Natural Resources sought ways to stretch its tire clean-up budget when it joined with Corrections in 1995. The inmates clean-up sites, then transport the tires to a site where they can be ground. They’re then mixed with coal to be burned at the University of Missouri-Columbia power plant.