Contamination by PCBs in a load of waste oil that was to burn in the kilns at Lehigh Portland Cement prompted the plant to suspend the burning of that fuel Nov. 12, said David H. Roush, manager of the Union Bridge plant.
Early Nov. 12, a load of 5,000 gallons of waste oil was delivered to Lehigh and blended into about 195,000 gallons of waste oil already in the storage tank at Lehigh, Mr. Roush said.
Laboratory tests done at the time showed a level of polychlorinated biphenyls (PCBs) higher than state and federal guidelines allow. The oil may have contained several hundred parts per million, compared to the allowed 50 parts per million, Mr. Roush said.
The man who had accepted delivery of the oil knowing its PCB level was an employee for Cemtech, the firm that contracts with Lehigh to run its alternative fuel operation, Mr. Roush said. The employee, a manager, has been fired by Cemtech.
Mr. Roush said Lehigh didn't know the oil was contaminated with PCBs until the Cemtech manager informed him about six hours vTC after it was added to the tank.
After accepting the oil, the Cemtech manager talked with Cemtech officials about the PCB level, Mr. Roush said. The Cemtech officials advised their manager to stop burning the oil and to inform Lehigh.
By then, about 1,000 gallons from the storage tank had been burned in the kiln. But Mr. Roush said that because the oil is heavy and doesn't mix quickly, it is possible none of the contaminated oil actually burned.
But Lehigh stopped using any waste oil in its storage tank, he said.
"We're being super-duper cautious," he said, because of the nature of PCBs. They don't degrade in the environment, and are highly monitored by environmental agencies, Mr. Roush said.
Until Cemtech makes plans to safely remove and dispose of the contaminated oil, he said, Lehigh will not use any of 200,000 gallons of waste oil in its storage tank.