The Nebraska Department of Environmental Quality announced that Ash Grove Cement Co has met all regulatory requirements and can proceed with using tyres as a supplemental fuel source at their Louisville facility.  
 
The decision was based on detailed agency review of data collected in 2005, during a trial period when Ash Grove was allowed to burn a mixture of tyres and coal at the Louisville facility. During this several-week "trial burn," extensive data was collected to determine how this additional fuel source affected emissions.  
 
"After reviewing the trial burn results, we found that the addition of scrap tires actually decreases the amount of pollutants being emitted," said NDEQ Director Mike Linder. "The use of scrap tires lowers the level of ozone-causing pollutants significantly. There are very slight increases in some metal emissions, but they are still well below any regulatory level of concern. In addition, the use of non-renewable fuels will decrease at the facility, which is positive as well." 
 
Although it was originally believed that Ash Grove would need to seek a construction permit prior to using tires as a fuel source on a permanent basis, the results of the trial burn demonstrated that a construction permit was not required.  
 
The only permit changes are to the existing operating permit, and those are minor changes to increase monitoring frequency, Linder said. There are no provisions in regulations requiring public notice of minor modifications of operating permits. Linder said the agency has concluded that all regulatory requirements have now been met, and Ash Grove is allowed to add a mixture of up to 30% tires with the coal at Kiln #2 at the Louisville plant.  
 
"We will continue to evaluate the monitoring of emissions at this facility to ensure that emission levels are protective of the environment," Linder said.