News Release
Release Number: | 02-018 |
Dated: | 2/11/2002 |
Contact: | Public Affairs Office, 503-808-4510 |
Portland, Ore.-The U.S. Army Corps of Engineers will begin retrieving electrical equipment from the Columbia River off Bradford Island at Bonneville Lock and Dam this week.
The Corps and the Oregon Department of Environmental Quality (DEQ), in cooperation with the National Marine Fisheries Service and U.S. Fish and Wildlife Service, developed a plan to remove the equipment and limit the impact to the environment during the removal. An unknown number of the pieces of equipment are believed to contain polychlorinated biphenyls (PCBs). PCBs build up in the environment and can cause harmful health effects to people and wildlife.
Turbidity screens will be anchored to the river bottom and extend to the surface around each of three debris removal areas. The screens are designed to block sediment movement out of the work area and will remain in place until turbidity monitoring indicates effects of removal have dissipated. Turbidity measurements will be taken at regularly scheduled intervals, upstream and downstream of the work area, and at the river surface, mid-depth and near the bottom of the river. Observers also will watch for any visible plumes or sheen on the river's surface. As an extra precaution, absorbent booms will be placed around the work areas.
Two barges will be used, one with a crane to lift equipment and other debris out of the river, the second a materials barge onto which the retrieved items will be loaded. The barges will remain outside of the turbidity screens (for complete information on the work plan, see https://www.nwp.usace.army.mil/issues/Bradford/next.htm ).
A team of divers from Advanced American Diving, Inc., of Portland, Ore., will be in the water to locate materials and guide the crane operator. Based on previous dive surveys, the Corps expects to remove an estimated 313 cubic yards of electrical debris. That's roughly equivalent to 31 10-cubic-yard dumpsters. Most of the electrical debris, switchgear, cable, etc., has never contained contaminants. Other debris, such as culverts and fencing materials, will be left in the water so that no excess sediment is disturbed.
Retrieval is expected to take 18 days. With a six-day-a-week schedule, the plan is to finish by March 2, 2002. The annual in-water work window that began in November ends on March 15, 2002. The accelerated schedule gives the Corps a few extra days, in case the weather - and river -- turn rough at Bonneville, keeping divers out of the water.
Final work is underway to validate raw data compiled from sediment, water and tissue samples taken last spring by URS Consulting and Advanced American Diving under contract to the Corps. The final report is expected to be available later this month. Enough information is available, however, to indicate the general nature of contamination in the local environment caused by the equipment in the river. The new data confirms earlier detections of PCBs in sediment and also identifies PCBs in the tissue of local clams and crayfish. PCBs were used as coolants and lubricants in electrical equipment until 1977. The Environmental Protection Agency has determined that PCBs are probably carcinogenic to humans.
Because PCBs enter the food chain, effects on fish (including fish listed under the Endangered Species Act) and bald eagles are of concern. Clams and crayfish are part of the food chain; contaminants can accumulate in their tissue and can be passed to other species. Sediment contamination near Bradford Island appears to be greatest in and very close to the debris mounds. The clams and crayfish stay in localized areas. Thus the overall food supply for larger fish and birds may only be minimally affected by the release of PCBs.
The materials in the river are adjacent to an historic landfill used by the Corps to dispose of household and project waste materials from 1942 until about 1982. In 1996, 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. Under the VCP Agreement, the Corps is working cooperatively with DEQ to complete the investigation, and any necessary cleanup or remediation, of the Bradford Island landfill. That agreement extends to materials being retrieved from the river.
DEQ, the Corps and other affected parties will continue to discuss future requirements, both in the river and the landfill. A final evaluation report on the landfill 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.