Bradford Island is the island in the Columbia River at Bonneville Dam between the spillway and the first powerhouse.
Until about 1982, a small landfill on Bradford Island was used to dispose of project waste materials like oil and grease, paint and solvents, scrap metals, mercury-vapor lamps, cables and sandblast grit. Some electrical transmission components like switchgear, insulators and possibly light ballasts were also in the landfill. Some household waste came from a small community of homes used by construction workers and later project personnel until 1976. The total landfill area is about a half acre in size (about one-third of a football field in area), and is estimated to hold about 8,800 cubic yards of material, including soil used to fill and cover the landfill. It is on the northeastern portion of Bradford Island, and is not in a public area. Other nearby potentially impacted areas on Bradford Island are included in this project.
The sandblast building material was used for sandblasting and painting from about 1958 to 1995. The area impacted by sandblast grit includes the sandblast area and an area where transformer oil was released onto the ground in 1995. A burn pit to the southeast of the sandblast building and a septic system northwest of the building (not currently in use) are more potential sources of contamination within the sandblast area. In addition, an area of previously unknown contamination was found in the course of soil sampling. An investigation in 2006 concluded there is an estimated 1500 cubic yards of contaminated material in the area.
A small area, approximately 95 cubic yards, on the south side of the island was used for small arms target practice through the 1970s. Lead concentrations have been detected.
The Corps began investigating the potential for contamination from these activities in 1998. In 2000, when electrical equipment was discovered submerged in the river adjacent to the landfill, the study was expanded to include the north shore of Bradford Island and potential impacts from that equipment. In 2002 we removed the electrical equipment from the river bottom and in 2007 dredged sediment from approximately one acre of river bottom to remove PCB contamination from the environment.