Bradford Island is part of the Bonneville Dam complex, which is located on the Columbia River at river mile 146.1, approximately 40 miles east of Portland, Oregon. The island has been the site of a variety of activities since dam construction including project maintenance, housing, equipment storage, chemical storage, and waste disposal.
The United States Army Corps of Engineers (USACE) began investigating the potential for contamination from historical disposal activities in 1997. Site investigations on Bradford Island began with evaluation of a landfill located near the eastern end on the island, which was used from the 1940s until the early 1980s. The USACE informed the United States Environmental Protection Agency (USEPA) and the Oregon Department of Environmental Quality (DEQ) of the presence of the landfill in 1996. The landfill was added to the DEQ Environmental Cleanup Site Information (ECSI) database in April 1997, and the Bonneville Dam Project Manager signed a DEQ Voluntary Cleanup Agreement letter for the landfill on February 18, 1998. In 2000, when electrical equipment was discovered submerged in the river adjacent to the landfill, investigations were expanded to include the Columbia River off the north shore of Bradford Island. In 2004, USACE elected to continue the Bradford Island project under the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) in accordance with Executive Order 12580.
Numerous investigations have been performed by the USACE and their contractors since 1997 to characterize and evaluate the contamination resulting from historical USACE activities at Bradford Island, with the site divided into two Operable Units (OUs), the Upland OU and the River OU. A review of site records, including employee interviews, site environmental audits, and environmental investigations resulted in the identification of four areas of potential concern (AOPCs) for the Upland OU: the Landfill AOPC, Sandblast Area AOPC, Pistol Range AOPC and Bulb Slope AOPC. The River OU is not subdivided and consists of the pooled area immediately upriver of the Bonneville Dam complex, known as the Bonneville Dam Forebay. The primary contaminants of interest that have been identified in soil and/or groundwater in the four Upland OU AOPCs include selected metals; polychlorinated biphenyls (PCBs); semivolatile organic compounds (SVOCs), including polycyclic aromatic hydrocarbons (PAHs); butyltins; volatile organic compounds (VOCs); and a few pesticides/herbicides. The contaminants of interest identified in offshore sediments and/or tissue samples for the River OU include selected metals, PCBs, pesticides, and PAHs.
Due to the PCB contamination in fish tissue, there is currently a fish advisory to not eat any resident fish between the Bonneville Dam and one mile upstream of the dam. More detail on the fish advisory can be found on the following Oregon Health Authority website: Bonneville Dam Fish Advisory.