Follow up tests of oil samples taken from a 431-foot derelict vessel, Davy Crockett, have detected low levels of polychlorinated biphenyls (PCBs).
Washington State Dept. of Ecology received reports Thursday of a light, non-recoverable sheen at mile marker 115 on the Columbia River, the site of the vessel. Oil samples taken from the engine room hold of the vessel detected approximately 3.44 parts per million (ppm) of PCBs. Coast Guard, Ecology, Oregon Dept. of Environmental Quality and other agencies responded and are working to cleanup oil and monitor the vessel. Federal regulations for PCBs in oil require specialized handling and disposal for levels at 50 ppm or greater.
Environmental and public health agencies’ regulations vary as to what constitutes acceptable concentrations of PCBs. Federal regulations require that water containing PCBs must be below 0.003 ppm to be discharged to navigable waters. One part per million is roughly the equivalent of one teaspoon per 1,300 gallons.
“The PCB-containing oil released from the barge is not an immediate public health risk,” said David McBride, a toxicologist with the Washington State Dept. of Health (DOH). “Existing advisories warn people to not eat any freshwater shellfish in the lower Columbia River, due to pre-existing contamination from historic releases of PCB.”
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