Ash Grove Cement Co in Louisville will begin a controversial test burn of scrap tyres on July 13, a company spokesman said. "We’re not sure of the number of days but it will be at least three days," said Ash Grove spokesman Lance Latham said. Ash Grove plans to add scrap tyres to coal and use the fuel mixture to power its cement kilns on the outskirts of this Cass County town. "Scrap tyres will be added at various rates to find the optimum (burning) rate for our process," Latham said. Ash Grove would like to burn one million scrap tyres annually in its cement kilns. In doing so, the company would save money on fossil fuels and help the environment by finding a beneficial use for discarded tires, Latham concluded.