The
Environmental Protection Agency moves forward this month with its official order
that the General Electric Co. pay for the removal of polychlorinated biphenyls
(PCBs) from the upper Hudson River. Planned costs to clean up the river are
about $500 million.
[At
right, the GE Hudson Falls Plant site. Courtesy of the EPA.]
“The administration is committed to cleaning up the Hudson River in a manner
that is environmentally sound and is responsive to the concerns of the affected
communities,” says EPA Administrator Christie Whitman. But opponents of the
plan fear disturbing the contaminated sediments. A new report evaluates the
science presented on both sides.
Since 1984, the debate over whether or not to dredge America’s largest Superfund
site of the toxic PCBs has centered on the technological feasibility and overall
environmental benefits. From the late 1940s until 1977, GE’s manufacturing plants
in Hudson Falls and Fort Edward, N.Y., released an estimated 200,000 to 1.3
million pounds of PCBs, used in the production of electric capacitors, into
the Hudson River. Under an agreement with the New York State Department of Environmental
Conservation (NYSDEC) in 1977, GE stopped discharging PCBs into the river. The
company is currently cooperating with the NYSDEC to prevent additional PCB leakage
into the river from its Hudson Falls plant.
The 209 different chemical compounds of PCBs accumulate in the fat tissues of
fish. Humans who consume contaminated fish increase their risk of cancer. Currently,
PCB pollution is such that only catch and release fishing is allowed in the
upper Hudson River, while health advisories recommend not eating too many fish
caught downstream.
GE’s major argument against dredging the river is the same as those of residents
opposed to the plan: the anticipated mixing of PCBs into the water column. Removing
the contaminated sediment may help the river speed up its natural cleaning process,
but it will still take decades to recover. Those against the dredging say the
short-term environmental damage and potential economic concerns are not worth
the long-term wait.
With EPA’s final decision in place, just how much resuspension of PCBs the plan
will allow and the methods for keeping those limits in check will be developed
this year as part of a 36-month design phase. The plan calls for the removal
of approximately 150,000 pounds of PCBs from a 40-mile stretch of the upper
Hudson River from just north of Albany to Fort Edwards.
In an effort to clarify the science surrounding the issue, the Hudson River
Foundation, a local research organization, asked University of Maryland’s Joel
Baker, an environmental chemistry professor, to organize a group of independent
scientists to evaluate the state of current knowledge. On Oct. 25, 2001,
the group of eight scientists publicized their paper, “PCBs in the Hudson River:
The Science Behind the Dredging Controversy.”
“The paper builds on the considerable amount of evidence EPA has acquired over
the past 20 years, but is not written specifically for EPA,” Baker says. “The
intent was to get a group who weren’t beholden to EPA, the environmental groups
or GE to try and take a more objective view and distill the science into a form
the general public could review.”
Working with Baker were: marine scientists Frank Bohlen of the University of
Connecticut and Bruce Brownawell of the State University of New York in Stony
Brook, earth and environmental scientist Richard Bopp at Rensselaer Polytechnic
Institute, ecotoxicologist Tracy Collier of the National Marine Fisheries Service,
environmental engineer Kevin Farley of Manhattan College, Rockwell Geyer of
the Woods Hole Oceanographic Institution and Rob Nairn, principal of Baird &
Associates.
Among its conclusions, the report says that the upper Hudson River is not predominately
a riverbed that accumulates sediment in an orderly fashion, but is more of a
“patchwork quilt” — some areas showing deposition while other areas erode depending
on the amount of seasonal runoff and river flow. “Under the prevailing average
flow conditions the sediments of the Thompson Island Pool [the northernmost
section of the 40-mile dredging plan] are a continuing source of PCBs to the
overlying waters,” the group writes. They add, “PCB release from the sediments
of the Upper Hudson River is the dominant current source of these contaminants
to the water column and food web.”
Is it better to take these sediments out of the river? “With the best dredging
techniques only a very small fraction of PCBs are released to the water, likely
less than 2 percent of the total PCBs dredged,” the report says. “In the Thompson
Island Pool, this short-term release is comparable to the rate at which PCBs
are currently being released from the sediments. Thus, with properly designed
and executed techniques, dredging may result in no more than a doubling of the
present day PCB flux during this project.”
The “worst case” scenario of twice as much PCBs floating back into the river
during a dredging operation is an option Merrilyn Pulver, the Fort Edward town
supervisor says she finds unacceptable.
But, “short-term degradation resulting from the dredging activity can mask eventual
benefits,” the scientists report. “Judging the ‘success’ or ‘failure’ of a remediation
will likely require a long-term view.” Baker is more specific: “We think it’s
a good thing to do,” he says about the dredging plan, “because it will accelerate
the cleaning up of the river. But the Hudson River is extremely contaminated
with PCBs and will be for generations, even with remediation.”
Christina Reed
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