Sludge samples taken from the canals of St. Clair Shores this year show dangerous levels of PCB contamination and indicate that the canal system is being recontaminated as state and federal officials work to clean it up, the Detroit Free Press reports.
Ed Van Hees, assistant professor of geology, said his samples taken in February, late March and early April found PCB levels ranging from 126 parts per million (ppm), to 700 ppm. That’s well below the 825,000 ppm the Environmental Protection Agency found in November, but well above the danger range. Federal guidelines consider findings of 50 ppm to designate an area a hazardous-waste site.
PCBs, or polychlorinated biphenyls, are industrial compounds banned in the 1970s after they were found to cause cancer.
A $10-million cleanup in 2001 brought PCB levels down to what the EPA considered a safe level of 10 ppm. The new findings mean that the earlier cleanup is negated because the pollutants are still leaking into the canals.
In March the EPA recommended that the area around the St. Clair Shores 10 mile drain be declared a Superfund site. If approved, this designation could mean more funds for cleanup.
The source of the ongoing contamination of the canals has not yet been identified.