Hanford Tank Farm RCRA Corrective Action Program

As a consequence of producing special nuclear material for the nation's defense, large amounts of extremely hazardous radioactive waste was created at the U.S. Department of Energy's (DOE) Hanford Site in south central Washington State. A little over 50 million gallons of this waste is now stored in 177 large, underground tanks on Hanford's Central Plateau in tank farms regulated under the Atomic Energy Act and the Resource, Conservation, and Recovery Act (RCRA). Over 60 tanks and associated infrastructure have released or are presumed to have released waste in the vadose zone. In 1998, DOE's Office of River Protection established the Hanford Tank Farm RCRA Corrective Action Program (RCAP) to: - Characterize the distribution and extent of the existing vadose zone contamination; - Determine how the contamination will move in the future; - Estimate the impacts of this contamination on groundwater and other media; - Develop and implement mitigative measures; - Develop corrective measures to be implemented as part of the final closure of the tank farm facilities. Since its creation, RCAP has made major advances in each of these areas, which will be discussed in this paper. (authors)