The U.S. Environmental Protection Agency said that dredging operations are expected to resume tomorrow in the Upper Hudson River. In 2014, dredging will begin south of Schuylerville, New York and proceed south towards Troy.
Dredging will also occur in a two-mile section of river near Fort Miller that is not easily accessed by boat. Dredging is being conducted to remove sediment from the river bottom that is contaminated with polychlorinated biphenyls (PCBs). PCBs were used in the production of electrical equipment at two General Electric facilities located in Hudson Falls and Fort Edward, New York. Over a 30-year period, ending in the late 1970’s, an estimated 1.3 million pounds of PCBs entered the river from the two GE plants. PCBs are potentially cancer-causing chemicals that build up in the food chain.
The dredging project, which began in 2009, targets approximately 2.65 million cubic yards of PCB-contaminated sediment from a 40-mile stretch of river between Fort Edward and Troy, New York. To date, more than 1.9 million cubic yards – approximately 70 percent – has been removed. The dredging goal for 2014 is to remove 350,000 cubic yards of contaminated sediment. It is anticipated that dredging could be completed during the 2015 dredging season. The remaining in-river work associated with habitat reconstruction and the closing of the Fort Edward, New York sediment dewatering and processing facility will follow the dredging.
“The EPA is now at a point from which we can see the finish line for this momentous cleanup that was decades in the making,” said Regional Administrator Judith A. Enck. “With nearly two million cubic yards of toxic sediment already removed, the EPA has taken an important step toward a healthier Hudson River and healthier river communities.”
Some challenging areas remain, but EPA worked with GE to identify creative solutions to meet these challenges. For example, the original plan called for sediment that will be dredged from the section of the river that cannot be reached directly by boat to be moved through the community in trucks. With input from the EPA, the community and the state of New York, GE revised its original plan to instead transfer the material to barges for transport to the sediment processing facility.
As the project continues further south in 2014, dredging will occur in discrete locations spread across 20-30 miles. Transporting the dredged material north by barge to GE’s sediment dewatering and processing facility located on the Champlain Canal in Fort Edward, New York, will require longer travel times and passage through several locks. Several of the areas that remain to be dredged are also logistically challenging, including those near dams, shallow areas around islands and the landlocked section of river.
During the dredging season, mechanical dredges mounted on deck barges use environmental dredge buckets to place dredged sediment into barges. Tugboats push the loaded barges to GE’s Fort Edward dewatering and sediment-processing facility. In the land-locked section of river, where direct water-transport of loaded barges to the processing facility isn’t possible due to the presence of dams at its north and south end, the loaded barges will be pushed by tugboat to a trans-loading station on a narrow section of land on the east shoreline of the river, south of the Thompson Island Dam. Once there, the material in the barge will be off-loaded into a bin on land and then re-loaded into another barge in the Champlain Canal “land-cut.” From there the barges will be pushed by tugboat upriver to the Fort Edward processing facility.
Once the loaded barges arrive at the processing facility, debris and water are removed. The coarse material is then separated from the fine sediment that contains most of the PCB contamination. The coarse material is staged in a pile before it is transported off-site by train to a properly licensed landfill. The remaining sediment is pumped to the dewatering facility where large filter presses squeeze water from the sediment. The water is treated to meet water quality standards before it is released back into the Champlain Canal. The remaining sediment and debris are also loaded onto railcars and transported by train to the permitted, off-site disposal facilities out of state.
In 2014, two shoreline support properties will be used for placing equipment in the river and staging the clean sand and gravel that is used to cover previously dredged areas. The Saratoga Barge Loading Area, which was also used as a support property in 2013, is located on Route 4 in Northumberland, about a mile north of Schuylerville. For 2014, an additional shoreline support property is being constructed on the west side of the river in Northumberland, within the landlocked section of river, to support the dredging work there.
Approximately 160,000 cubic yards of PCB-contaminated sediment is targeted for removal from 29-acres of river bottom in the land-locked section of river. The work is expected to start in June once the site is constructed to allow mobilization of equipment into the river. Once the work is completed in this area the trans-loading station on the eastern shoreline and the facility in Fort Miller will be returned to their previous condition.
Water quality monitoring will continue to measure PCB levels at various downstream monitoring locations and to track the movement of dredged material downriver. Air monitors are also placed near dredging operations and around the processing facility while work is underway. The EPA also requires other monitoring to reduce the effects of dredging and dewatering operations on surrounding communities.
The EPA is overseeing the dredging project that is being conducted by GE under the terms of a 2006 legal agreement. The New York State Department of Environmental Conservation is supporting the EPA in overseeing the cleanup.
Press Release, May 6, 2014