International Dredging Review

International Dredging Review

The U.S. Environmental Protection Agency (EPA) has reopened the door to further dredging in the Hudson River at least a little bit.

Five weeks after giving General Electric Co. permission to close and dismantle the plant it used for the last seven years to treat contaminated sediment dredged from the river bottom EPA announced that the agency would not certify that GE has finished cleaning up the river until the summer of 2017 at the earliest.

In a letter to the leaders of five environmental groups dated December 18 Mathy Stanislaus and Judith Enck insisted that decommissioning the plant “does not preclude future dredging.” Stanislaus is assistant administrator of the EPA’s Office of Land and Emergency Management. Enck is administrator of EPA’s Region 2 administrator which covers New Jersey and New York.

The environmentalists all part of the Community Advisory Group to the Hudson River cleanup had joined the Federal Hudson River Natural Resource Trustees (The U.S. Department of the Interior and the National Oceanic and Atmospheric Administration) in urging the EPA to postpone any decision on closing the treatment plant until after a new review had been conducted of the state of the river.


During 2015 in what was thought to be the last year of dredging dredges worked to remove sediment along the Hudson River. After the final season of scheduled dredging the EPA has not closed the door yet on more possible dredging in the future.

The federal trustees claimed the model on which the 2002 Record of Decision to cleanup GE’s contamination of the river with PCBs was flawed – dramatically underestimating the level of contamination and overestimating how quickly PCBs decayed. The trustees said that the 8000 sediment cores collected in the three years after the Record of Decision showed that PCB concentrations were two-to-three times higher than EPA expected. Coupled with slower than expected decay rates the trustees said that meant PCB concentrations in post-remediation sediments would be three-to-five times higher than the level targeted by EPA.

Thomas Brosnan Hudson River case manager for the NOAA and Kathryn Jahn Hudson River case manager for the Interior Department laid out the trustees’ arguments in a September 28 letter to the director of Region 2 EPA. They added that there would be “substantial benefits” from “additional removal of PCB contaminated sediment in the Upper Hudson.”

Stanislaus and Enck wrote that they had no legal basis on which to stop the decommissioning of the treatment facility but they agreed to the trustees’ request to move up the start of the next Five Year Review to 2016. EPA met with the trustees on December 16 to discuss the scope of sediment water and fish data that should be collected for the review.

The consent decree that established GE’s responsibility to cleanup the Hudson River establishes a detailed series of steps that must be completed before EPA can certify that GE has completed remedial action. EPA estimates that the Five Year Review will be completed before EPA has to respond to any request the company might make to the agency to certify that it has completed the cleanup. The review will determine if GE has met the terms of the consent decree or must take further action which could include additional dredging. EPA looks to finish the review by April 23 2017.

Between 1947 and 1977 GE discharged an estimated 1.3 million pounds of PCBs into the Hudson River from manufacturing plants in Fort Edward and Hudson Falls New York. Once in the river the PCBs settled and mixed with the sediments on the river bottom.

PCBs are considered probable human carcinogens and are linked to a variety of other health disorders. Since 1976 New York State has closed recreational and commercial fisheries on the river because of high levels of PCBs in the fish. EPA listed 200 miles of the river from Hudson Falls to the Battery in New York City as one of the country’s most contaminated hazardous waste sites in 1984.

EPA’s Record of Decision in February 2002 called for targeted dredging of approximately 2.65 million cubic yards of PCB-contaminated sediment from a 40-mile section of the Upper Hudson River from Fort Edward to Troy New York. That dredging began in 2009 and finished in November 2015. In all approximately 2.75 million cubic yards of PCB-contaminated sediment were removed from the river bottom under the terms of a 2006 legal agreement between GE and EPA.