COLUMBIA, SC — A toxin that somehow worked its way into Upstate sewage sludge has not shown up in the sludge at Columbias wastewater treatment plant, city officials said Monday.
Laboratory tests completed last week did not reveal the presence of PCBs, poisonous industrial compounds banned by the federal government more than three decades ago because of their health threats. PCBs are believed to cause cancer and a variety of other ailments.
PCBs in sewage sludge are a concern because waste sludge is either spread on fields as fertilizer for some crops or shipped to garbage landfills for disposal. A key worry is that PCBs could contaminate groundwater or crops. Columbias sewage sludge goes to Waste Managements Screaming Eagle Road garbage landfill in northeast Richland County.
Across the Upstate PCBs have been found in sludge at a string of wastewater plants. The findings have sparked a state and federal criminal investigation of illegal dumping. The state has suspended the license of one septic tank service as it continues the investigation.
The S.C. Department of Health and Environmental Control, in the meantime, has issued an emergency regulation banning the use of sludge with any detectable PCB levels on farmland.
Victoria Kramer, a spokeswoman for Columbias utilities department, said sludge test results are good news for the city, but she said businesses need to be on the alert for unscrupulous people who might dump waste PCBs into grease traps. Grease traps are devices that catch grease from restaurant kitchens. The traps periodically are cleaned out by haulers. Some materials tossed in grease traps could trickle into sewer pipes.
We are pleased that these samples came back as no detects, but we still want to remind our customers with grease traps that they can protect themselves by safeguarding the grease traps, Kramer said.
Mondays findings follow results last week showing that PCBs had not been found in the sludge of another Columbia-area sewer system operated by the East Richland Public Service District.
East Richland officials had discovered PCBs last month in the grease trap of a restaurant on Sparkleberry Lane, prompting concern that sewer plants could be affected by PCBs that flowed through the system. A trace amount of PCBs showed up in a pump station near the restaurant, but they were not flowing out and the station has been cleaned, East Richland director Larry Brazell said.