Superfund Site: HANFORD 300-AREA (USDOE)
BENTON COUNTY, WA
Superfund Site Profile
Located in southeastern Washington State, Hanford is a 586-square-mile site created in 1943 as part of the Manhattan Project (America’s effort to develop the atomic bomb).
Operation of the plutonium-producing facilities continued beyond World War II through the Cold War, and a total of nine nuclear reactors were eventually constructed along the Columbia River.
In 1989, production stopped and work shifted to cleanup of portions of the site contaminated with hazardous substances, including both radionuclides and chemical waste.
The operations at Hanford created one of the largest and most complex cleanup projects in the U.S. Weapons production resulted in more than 43 million cubic yards of radioactive waste, and over 130 million cubic yards of contaminated soil and debris. Approximately 475 billion gallons of contaminated water was discharged to the soil. Some of the contaminants have made it to groundwater under the site. Over 80 square miles of groundwater is contaminated to levels above groundwater protection standards.
In 1988, Hanford was divided into four National Priorities List (NPL) sites, including the 100, 200, 300, and 1100 Areas.
The Hanford 300 Area is composed of a 0.52-square-mile industrial complex and one square mile of surrounding areas used for solid and liquid waste disposal next to the Columbia River about one mile north of Richland, Washington. It is one of the three areas at the Hanford Nuclear Reservation on EPA's National Priorities List (NPL); the other two are the 100 and 200 Areas. These areas are part of a Department of Energy (DOE) complex that includes buildings, disposal sites, an environmental research park and vacant land covering about 586 square miles. The DOE fabricated fuel for nuclear reactors in the 300-Area and used other 300-Area facilities for research and development purposes. The 300-Area site includes an unlined liquid disposal area north of the on-site industrial complex area, landfills and miscellaneous disposal sites associated with operations at the industrial complex.
DOE and its predecessor disposed of about 27 million cubic yards of solid and diluted liquid wastes mixed with radioactive and hazardous wastes in ponds, trenches and landfills in the 300-Area. The areas used for liquid discharges had no outlets; therefore, liquids percolated through the soil into the groundwater and the Columbia River, which is located directly east and downgradient from the 300-Area. These activities contaminated soil, groundwater and surface water with hazardous chemicals, radioactive constituents, heavy metals and polychlorinated biphenyls (PCBs). EPA divided the site into several cleanup areas, or operable units (OUs), to better address site contamination. Remedy construction has been completed at several OUs.
Remedial investigations, removal actions and remedy design and construction are underway at the remaining OUs.