News Release
| Release Number: | 01-056 |
| Dated: | 4/24/2001 |
| Contact: | Public Affairs Office, 503-808-4510 |
Portland, Ore. - The U.S. Army Corps of Engineers has issued a dive contract for work in the Columbia River near Bonneville Dam. Divers will begin work in the river April 30, but they will be doing different jobs than those planned earlier.
National Marine Fisheries Service (NMFS), U.S. Fish and Wildlife Service (USFWS), the Oregon Department of Environmental Quality (DEQ) and the Corps discussed plans to remove all potentially contaminated power transmission equipment from the river in February.
When test results from sediment samples gathered from the Columbia River near Bonneville and observations from the December dive were evaluated, however, the agencies agreed to modify plans for the dive. As announced by the Corps in January, samples contained PCBs (polychlorinated biphenyls), classified as probable cancer causing chemicals by the Environmental Protection Agency (EPA). PCBs also enter the food chain, thus affects on fish (including fish listed under the Endangered Species Act) and bald eagles are of concern. Planning changes meant delays as the Corps had to get NMFS agreement for work in the river outside of the inwater work period which ended March 1. That agreement was reached.
The focus of the April-May work will be to better define the existing conditions before equipment that could contain PCBs is recovered. The dive as currently planned will take up to six days, rather than the two weeks previously allotted to remove the remaining equipment.
Divers will be placing anchors, columns and floats to hold membranes (lipid sheets or polyethylene sheets) in the river. Such membranes can be tested to determine PCB levels in the water column. They will take more sediment samples in and around the three known debris mounds and downstream by drains from a sandblast area. All will be analyzed for PCBs and some for a range of contaminants found earlier in the landfill, such as metals. They will map the three debris mounds to estimate the quantity and types of materials present. The dive survey will be extended further downstream, toward the spillway, as planned in December but cancelled because of weather. If more debris is found, the areas will be mapped and contents detailed to the extent possible. Because living organisms feed on materials that could contain PCBs that accumulate in tissue, divers also will gather freshwater clams and crawfish for tissue analyses.
"DEQ and the Corps initially agreed on a plan that would get potentially contaminated pieces of equipment out of the river as quickly as possible," said Dawn Edwards, Corps public affairs specialist. "When the Corps originally talked with NMFS and USFWS because of the Endangered Species Act issues involved, they thought removing the equipment sounded like the right move. During later discussions more concerns surfaced. Bottom line, we had to rethink our approach to the problem. Everyone wants to make sure harm is minimized, not increased."
"Our approach was to take reasonable precautions and remove the PCB containing electrical equipment and then assess any contaminated sediment," said Matt McClincy, DEQ. "Based on the initial survey of the area in November by Corps contract divers, the recovery work was expected to take two days and appeared pretty straightforward. Once the divers started working in the debris area, they uncovered more electrical equipment than we anticipated. Some of it is partially buried. The scale of the recovery effort changed. After discussing the situation with the agencies, we agreed that we should take a step back and try to better define the situation."
"We weighed the need to remove a potential source of PCBs from the river with the possible risk from the sediment that would be stirred up by the removal," said Ben Meyer, fishery biologist, NMFS. "What we decided is that we need more information before we remove the equipment. We need to know whether PCBs are in the water column now, and the ways water currents move the sediment around in that part of the river."
"That's what we'll be getting out of the next dive work," said Jeremy Buck, contaminants specialist, U.S. Fish and Wildlife Service. "The tests we're working out will give us information to help us jointly decide on the best next steps."
"We're disappointed we can't get the equipment out of the river right now," said Edwards, "but we understand that acting quickly could add harm, not reduce it. We were all in consensus: we don't want to add to the damage."
The Corps took the sediment samples in December 2000, during a dive to recover power transmission system components. Other components retrieved and analyzed in November proved positive for PCBs.
Of four sediment samples gathered in December, three were above screening levels (benchmarks) developed by regional regulatory agencies and the Corps for dredged material (sand or sediment) to be deposited in water. No PCBs were detected in the fourth sample, gathered five feet from a capacitor.
The materials in the river are adjacent to an historic landfill. The Corps identified the landfill site, used by the Corps to dispose of household and project waste materials from 1942 until about 1982, as an area of concern during routine internal inspections. A primary concern was contaminant migration from the landfill into the sediments or water of the Columbia River. In 1996, following further internal investigations and confirmation of landfill contents, the Corps notified DEQ about the landfill and the Corps' intent to investigate potential contamination at the site. To assure the landfill investigation would comply with regulatory agency requirements, a Voluntary Cleanup Program (VCP) agreement was signed in 1998 between DEQ and the Corps. The VCP makes the two agencies partners in the investigation, and any necessary cleanup or remediation, of the Bradford Island landfill. That agreement extends to materials being retrieved from the river.
The landfill site investigation is continuing and a final evaluation report is expected in spring 2002. Remedial actions, if needed, will follow when the investigation is completed. The landfill is in a part of Bradford Island that is not open to the public. It is forested and managed as wildlife habitat.