Dredging has been cut back on some parts of the upper Hudson River after higher-than-expected levels of resuspended PCBs were found in river water last week, federal officials said Thursday.
Monitors six miles downriver from the dredging showed levels of PCBs in the water exceeding 400 parts per trillion on two consecutive days. The federal drinking water standard for PCBs is no more than 500 parts per trillion.
The levels of resuspended PCBs have dropped since General Electric Co. contractors changed dredging methods late last week, said Kristen Skopeck, a spokeswoman for the Environmental Protection Agency’s Hudson River field office in Fort Edward.
Nevertheless, an anti-dredging citizens group is urging the EPA to shut down the $780 million environmental dredging project because they say it is contaminating the air and water in the Fort Edward-Moreau area where the dredges are working.
The first phase of the large-scale dredge project started May 15 in the river near Rogers Island in Fort Edward. Work is scheduled to continue 24 hours a day, six days a week into early November.
Air quality monitors near Champlain Canal Lock 7 on the Hudson showed higher-than-allowed levels of PCBs in the air on the same days the high levels of PCBs were reported in the water.
“The EPA is exceeding the safety levels and they are not even at full production,” said Tim Havens Sr., president of the organization CEASE (Citizen Environmentalists Against Sludge Encapsulation).
“After years of dismissing the idea that dredging will cause the resuspension of considerable amounts of PCBs, causing water levels to spike and volatilization into the air, EPA officials now not only admit that resuspension is occurring, but also that noise and air quality levels have reached the threshold that EPA is supposed to use to shut the project down,” Havens said in a written statement.
David King, director of EPA’s Hudson River field office, on Thursday said that dredging is currently being done in a section of the river near Rogers Island where PCB contamination of river sediment is very high.
On July 15 and 16, river water monitors at the Thompson Island Dam showed 413.4 parts per trillion PCBs and 422.3 ppt PCBs, respectively, in the river water.
However, farther downriver, at the water monitor in Waterford, the readings were much lower: 56.2 ppt and 66.6 ppt for the same two days.
When dredging methods were changed after these resuspension spikes, the readings dropped to 336.4 ppt on July 18 and 253 ppt on July 20, according to EPA figures. The readings went back up to 333 ppt on July 21.
Mark L. Behan, a GE spokesman, said Thursday that contractors doing the dredging for GE have reduced the pace of dredging in some areas.
The dredge operators have also changed the way the river sludge is loaded, making sure that the contaminated material is always covered with water so PCBs aren’t released into the air.
As many as 11 dredges are working in 10 of the 18 areas where dredging will occur this year on the upper Hudson, Behan said.
“Adjustments will continue to be made in response to [water and air] data,” Behan said.
The EPA ordered GE in 2002 to pay for and conduct the environmental dredging of 2.65 million cubic yards of PCB-contaminated river bottom sediment between Fort Edward and Troy. The production target for the project’s first phase is 260,000 cubic yards.
GE capacitor plants in Fort Edward and Hudson Falls discharged an estimated 1.3 million pounds of PCBs (polychlorinated biphenyls, a probable carcinogen that causes other health problems in humans and wildlife) for 30 years, ending in 1977 when the practice was banned.