Seven Hudson Drinking Water Supplies Tested For PCBs
The State Department of Health recently provided drinking water test results for PCBs to seven water supply systems that receive their drinking water from the Hudson River. Drinking water test results for Waterford, Stillwater, Halfmoon, Poughkeepsie, Green Island, Rhinebeck and Port Ewen were all within drinking water standards as set under the federal Safe Drinking Water Act. This testing is part of a monitoring program funded by the U.S. Environmental Protection Agency (EPA).
DOH began monitoring these drinking water supplies for PCBs in May 2008 to establish a baseline before General Electric begins dredging PCB-contaminated sediments in 2009. Samples collected before dredging will be compared to samples collected during dredging to help determine whether water quality changes. The state Health Department has been working with water suppliers, local health departments, the state Department of Environmental Conservation, local elected officials and the EPA. Sampling will continue through September of this year.
The first two rounds of test results showed that PCBs are in the drinking water of the water supply systems sampled. "The concentrations found are below the state drinking water standard of 500 parts per trillion (ppt) for PCBs established by the EPA," said Nancy K. Kim, Ph.D., Interim Director of the DOH Center for Environmental Health. PCBs in source and treated water ranged from less than 5.1 ppt to 159.0 ppt. Treated water samples ranged from about 3 times to more than 50 times below the standard.
DOH is using two methods to detect PCBs at lower concentrations than routine monitoring. One method is an enhanced version of the US EPA Method 508, the method used by most public water suppliers to determine whether PCB levels are below the drinking water standard. The second method is called the Green Bay Method. This method provides more detailed information about specific kinds of PCBs. It has previously been used to measure PCBs in Hudson River water and will be used to monitor the effect of dredging on PCB levels in river water when dredging begins next year.