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|Dredging Boat in Bangladesh|
In the first phase of the cleanup, nearly 37% of the area was capped due to the continued presence of contamination, despite multiple dredging passes that removed the great majority of the PCBs. Capping in 15% percent of the area was unavoidable because of physical barriers in the river, leaving 22% percent capped in areas without these barriers. While fish and other aquatic life are not exposed to the contamination in the capped areas, the EPA has determined that it is necessary in Phase 2 to set a stringent limit on what percentage of the total project area can be capped if dredging does not meet the cleanup goals. This limit will be set at 11% of the total project area, not counting those areas where capping is unavoidable. This limit represents a significant improvement from Phase 1 and will require GE to employ considerably more rigorous dredging procedures.
Dredging during the second phase will go deeper into the sediment and, by relying on better information and lessons learned during the first phase, will remove more contaminated sediment in fewer passes. Phase two will require GE to remove an estimated 95 percent or more of PCBs from the areas designated for dredging.