USA: GE Urges for Clear Standards to Protect Hudson River From Dredging Impact

To protect the Upper and Lower Hudson River in the next phase of the Upper Hudson River dredging project, GE today urged a panel of independent scientists to recommend the establishment of firm, accountable, science-based standards to ensure that dredging itself does not slow down the river’s environmental recovery.The independent scientists are peer reviewers who were chosen to evaluate the first phase of the dredging project that was conducted between May and November 2009. After evaluating data and hearing presentations from GE and EPA, most members of the peer review panel suggested in preliminary comments that they believed the performance standards EPA set to govern Phase 1 of the project needed to be changed before Phase 2 begins.

GE had recommended adjustments in the standards, and in its final presentation to the three-day peer review meeting, urged the panel to recommend:

* The establishment of firm limits on the mass of PCBs that the process of dredging itself is permitted to introduce to both the Upper and Lower Hudson River during the second phase of the clean-up project;

* The use of quantitative computer modeling to establish the limits for the upper and lower river to ensure that dredging itself does not introduce more PCBs than would otherwise be available to fish; and,

* The establishment of clear, practical, explicit standards, rather than conceptual goals, to govern the entire project and to ensure accountability for one of the largest and most logistically complex environmental dredging projects ever undertaken.

GE Hudson River Project Manager John Haggard told the panel that if the model is used to set limits on the mass of PCBs that dredging can reintroduce to both the upper and lower river, EPA’s clean-up goals for the Hudson will be achieved. “We will make this river better,” he said. Mr. Haggard reminded the panel that EPA’s original goal in choosing dredging was to reduce PCB levels in fish in the Upper Hudson. The first phase of dredging, however, produced the opposite result: Increases in PCB levels in fish of between 40 and 500 percent between Fort Edward and Albany. “We need to protect the entire river,” Mr. Haggard said. EPA has proposed no limit on the amount of PCBs that dredging would be allowed to resuspend into the Upper Hudson. Moreover, EPA proposed abandoning the federal drinking water limit as a standard for the automatic shutdown of the dredging project. As for the lower river, GE encouraged the peer reviewers to consider recommending that no more than 1,200 kilograms (approximately 2,600 pounds) of PCBs — and perhaps less — be permitted to flow to the Lower Hudson as a result of dredging. Mr. Haggard said an even lower standard may ultimately be warranted based on an analysis of the continuing impact of PCBs that were resuspended during dredging and redeposited across the river bottom. He said the ultimate limit should be a “break-even point” that would ensure that the mass of PCBs flowing to the Lower Hudson during dredging would be no more than would otherwise have flowed to the lower river without dredging.

This would minimize impacts to the Lower Hudson as a result of the cleanup in the Upper Hudson. It would also accelerate the recovery of the lower river, achieving EPA’s goal that in 20 years PCB levels in fish after dredging would be lower than if dredging had not occurred. During the peer review sessions, EPA said one percent of whatever mass of PCBs is removed from the Upper Hudson should be allowed to flow to the Lower Hudson, without a maximum limit. As a result, EPA acknowledged, there is only a 50/50 chance in the next 40 years — not the 20 years EPA originally forecast — that dredging will result in lower PCB levels in the Lower Hudson than if dredging had never happened. EPA has indicated it does not intend to update its 10-year-old model to forecast future river conditions (it says it does not accurately portray the river’s recovery rate) even though nearly 70,000 new pieces of data have been collected since the model was built and a significant dredging project was completed. GE commissioned Dr. John Connolly, a member of the National Academy of Engineering, to update the GE model he built to forecast future river conditions.

GE and Dr. Connolly committed to working with EPA to come to an agreement on the use of the model to identify and evaluate the most effective clean-up strategy for Phase 2 and to resolve other technical issues. EPA made no similar commitment. EPA’s Ben Conetta said the agency would “likely look” at information GE submits, but said the agency did not want additional data collection or analysis to delay moving ahead with Phase 2. Dr. Connolly pointed out that EPA’s national guidance recommends the use of quantitative models at contaminated sediment sites, and models are used at almost every major contaminated sediment site in the country. The GE model is among the most sophisticated ever developed. “The model is an unprecedented tool calibrated to the best data set ever collected on an environmental remedial project,” Dr. Connolly said. “It integrates tremendous information about river conditions and processes. We don’t have to guess at the interaction between variables. We should use the model to establish the load standards for the upper and lower rivers.”

GE embraced the recommendations of several peer reviewers to collect additional data to determine the depth of PCB contamination in some areas of the Upper Hudson where river-bottom debris has made accurate sampling difficult. GE also suggested that data be collected on river conditions year-round to account for the continuing impacts of dredging. After Phase 1, PCB levels in water and fish remained elevated above historic baselines for six months and perhaps longer. To address the problem of repeated dredging passes to capture small amounts of PCBs, exacerbating resuspension and impeding productivity, GE recommended a more streamlined approach to removing residual PCBs. GE would collect additional data to more precisely characterize the depth of contamination, then dredge to that depth, and then swiftly cap the dredged area with clean material. This would ensure that dredged areas were closed up quickly, reducing resuspension and allowing the project to achieve the timetable EPA established. GE said it favored completing the dredging project as quickly as possible, and as close to the five-year schedule that EPA originally established, to curtail the impacts of dredging and allow the benefits of the cleanup to be realized more quickly.


Source: hudsondredging, May 7, 2010;