Louisville, Neb. ? Ash Grove Cement Co. wants to burn scrap tires instead of coal at its plant, but the state chapter of the Sierra Club is worried about carcinogens and lead.

The Overland Park, Kan.-based company already burns scrap tires at six of nine cement plants and has applied for an air quality permit from the Department of Environmental Quality.

“They would like to basically change their fuel source,” department spokesman Rich Webster said Friday.

Plant officials want to replace up to 30 percent of the coal it burns in cement kilns, according to the application. The company has said it would like to burn 1 million scrap tires annually.

But the state chapter of the Sierra Club is opposed to the plan. Spokeswoman Cammy Watkins said the group will oppose the permit because burning scrap tires sends toxic gases, pollutants and lead into the air.

The company has said burning tires instead of coal would save money on fossil fuels and help the environment by making use of scrap tires.

A test burn in October 2005 at the plant showed significant reductions in nitrogen oxide, sulfur oxide and dust emissions when the scrap tires were used. Emissions of hazardous compounds increased in low amounts.

Webster said the company applied for the permit in December, and the state is still reviewing the application.

“It takes quite a while to determine if an application is complete. Quite often they are not,” Webster said.

Webster said the state would write a proposed permit for the company that will be put out for public review, with anyone able to ask for a public hearing.