Report: Hudson River dredge season good

PHOTOGRAPHER: Lee Coleman

Despite spring floods and high water on the upper Hudson River this summer, the dredging of PCBs from the river never caused excessive amounts of the hazardous chemicals to be resuspended in the water, officials said Thursday.

This is a major departure from the first phase of the dredge project in 2009, when the safe drinking water standard — PCB levels of 500 parts per trillion — was exceeded at least four times.

The massive environmental cleanup project was shut down four times in the summer and fall of 2009 because such large amounts of PCBs (polychlorinated biphenyls, a probable carcinogen) were stirred up from the river bottom.

The floods on the upper Hudson this May delayed the start of the project for three weeks but tropical storms Irene and Lee didn’t have a significant impact on the upper river, according to dredge project officials.

“Resuspension numbers have been good throughout the season,” said Tim Kruppenbacher, an operations manager for General Electric Co. He gave a project update on the dredging Thursday at a meeting of the project’s Community Advisory Group in Fort Edward.

Resuspension levels through the spring and summer at the PCB water column monitor near the Thompson Island Dam were in the 200 ppt range and at the monitor in Waterford the PCB readings were 100 ppt or less, Kruppenbacher said.

The Environmental Protection Agency ordered GE to conduct and pay for the estimated $850 million cleanup project in 2002.

The larger second phase of the PCB dredge project started in early June and will continue through October. The dredge work will resume next year and is expected to take between five and seven years to complete.

Even though the project was delayed three weeks, GE contractors are nearing the goal of 300,000 cubic yards of contaminated sediment dredged this season. As of last Sunday, 216,000 cubic yards had been removed, officials said. The material is dumped into barges and floated to the 100-acre river sludge dewatering and processing plant on the Champlain Canal in Fort Edward.

The processed sediments are loaded onto covered train cars and taken to hazardous waste landfills in Michigan and Idaho.

After the first phase of the dredge work was completed between Fort Edward and Moreau, an independent panel of scientists and engineers reviewed the results and made recommendations. GE and EPA officials said Thursday these recommended changes, including the way the dredging is done and the number of dredges on the river, have been followed:

u Instead of 12 dredge platforms, only three are being used.

u Instead of a dredge making multiple swipes at the river bottom to remove sediment, the dredges take only two passes at the targeted area. Kruppenbacher said better river bottom samples, including thousands taken this year and last, allow the dredge operators to pinpoint the depth of contamination.

Manna Jo Greene, environmental director for the Hudson River Sloop Clearwater Inc. and a advisory group member, said she is pleased with the way the project is being managed in Phase 2 as compared with Phase 1.

She and others, however, asked why about 135 acres of PCB-contaminated river bottom near the areas scheduled to be dredged couldn’t be added to the project.

David King, director of the EPA’s Hudson River Field Office, said the approved design of the project never intended to remove all of the PCBs from the upper Hudson between Fort Edward and Troy, just the most contaminated sediments. He said the federal record of decision for the Superfund project — extensively discussed before approval — will not be changed at this point in the process.

GE plants in Hudson Falls and Fort Edward discharged an estimated 1.3 million pounds of PCBs into the river for 30 years, ending in 1977 when the practice was banned.