A major issue in the cleanup of this country's nuclear weapons complex is how to dispose of the radioactive waste resulting primarily from the chemical processing operations for the recovery of plutonium and other defense strategic nuclear materials. The wastes are stored in hundreds of large underground tanks at four U.S. Department of Energy (DOE) sites throughout the United States. The tanks contain hundreds of thousands of cubic meters of radioactive and hazardous waste. Most of it is high-level waste (HLW), some of it is transuranic (TRU) or low- level waste (LLW), and essentially all containing significant amounts of chemicals deemed hazardous. Of the 278 tanks involved, about 70 are known or assumed to have leaked some of their contents to the environment. The remediation of the tanks and their contents requires the development of new technologies to enable cleanup and minimize costs while meeting various health, safety, and environmental objectives. While DOE has a process based on stakeholder participation for screening and formulating technology needs, it lacks transparency (in terms of being apparent to all concerned decision makers and other interested parties) and a systematic basis (in terms of identifying end states for the contaminants and developing pathways to these states from the present conditions). An End State Methodology for Identifying Technology Needs for Environmental Management, with an Example from the Hanford Site Tanks describes an approach for identifying technology development needs that is both systematic and transparent to enhance the cleanup and remediation of the tank contents and their sites. The authoring committee believes that the recommended end state based approach can be applied to DOE waste management in general, not just to waste in tanks. The approach is illustrated through an example based on the tanks at the DOE Hanford Site in southeastern Washington state, the location of some 60 percent by volume of the tank waste residues.

The National Academies' National Research Council undertook this study in response to a request from the Under Secretary of Energy to provide strategic advice on how the Department of Energy could improve its Environmental Quality R&D portfolio. The committee recommends that DOE develop strategic goals and objectives for its EQ business line that explicitly incorporate a more comprehensive, long-term view of its EQ responsibilities. For example, these goals and objectives should emphasize long-term stewardship and the importance of limiting contamination and materials management problems, including the generation of wastes and contaminated media, in ongoing and future DOE operations.

The Department of Energy's Environmental Management Program (DOEEM) is one of the largest environmental clean up efforts in world history. The EM division charged with developing or finding technologies to accomplish this massive task, its Office of Science and Technology (OST), has been reviewed extensively, including six reports from committees of the National Research Council's (NRC's) Board on Radioactive Waste Management (BRWM) that have been released since December 1998. These committees examined different components of OST's technology development program, including its decision-making and peer review processes and its efforts to develop technologies in the areas of decontamination and decommissioning, waste forms for mixed waste, tank waste, and subsurface contamination. Gerald Boyd, head of OST, asked the Board on Radioactive Waste Management (BRWM) to summarize the major findings and recommendations of the six reports and synthesize any common issues into a number of overarching recommendations.

The Hanford Site was established by the federal government in 1943 as part of the secret wartime effort to produce plutonium for nuclear weapons. The site operated for about four decades and produced roughly two thirds of the 100 metric tons of plutonium in the U.S. inventory. Millions of cubic meters of radioactive and chemically hazardous wastes, the by-product of plutonium production, were stored in tanks and ancillary facilities at the site or disposed or discharged to the subsurface, the atmosphere, or the Columbia River. In the late 1980s, the primary mission of the Hanford Site changed from plutonium production to environmental restoration. The federal government, through the U.S. Department of Energy (DOE), began to invest human and financial resources to stabilize and, where possible, remediate the legacy of environmental contamination created by the defense mission. During the past few years, this financial investment has exceeded $1 billion annually. DOE, which is responsible for cleanup of the entire weapons complex, estimates that the cleanup program at Hanford will last until at least 2046 and will cost U.S. taxpayers on the order of $85 billion. Science and Technology for Environmental Cleanup at Hanford provides background information on the Hanford Site and its Integration Project,discusses the System Assessment Capability, an Integration Project-developed risk assessment tool to estimate quantitative effects of contaminant releases, and reviews the technical elements of the scierovides programmatic-level recommendations.

When the Cold War abruptly ended, DOE halted most nuclear materials production. In 1995, Congress chartered DOE's Environmental Management Science Program (EMSP) to bring the nation's scientific infrastructure to bear on EM's most difficult, long-term cleanup challenges. The EMSP provides grants to investigators in industry, national laboratories, and universities to undertake research that may help address these cleanup challenges. On several occasions the EMSP has asked the National Academies for advice on developing its research agenda. This report resulted from a 15-month study by an Academies committee on long-term research needs for deactivation and decommissioning (D&D) at DOE sites.

DOE Tank Waste: How clean is clean enough? The U.S. Congress asked the National Academies to evaluate the Department of Energy's (DOE's) plans for cleaning up defense-related radioactive wastes stored in underground tanks at three sites: the Hanford Site in Washington State, the Savannah River Site in South Carolina, and the Idaho National Laboratory. DOE plans to remove the waste from the tanks, separate out high-level radioactive waste to be shipped to an off-site geological repository, and dispose of the remaining lower-activity waste onsite. The report concludes that DOE's overall plan is workable, but some important challenges must be overcomeâ€"including the removal of residual waste from some tanks, especially at Hanford and Savannah River. The report recommends that DOE pursue a more risk-informed, consistent, participatory, and transparent for making decisions about how much waste to retrieve from tanks and how much to dispose of onsite. The report offers several other detailed recommendations to improve the technical soundness of DOE's tank cleanup plans.

A major issue in the cleanup of this country's nuclear weapons complex is how to dispose of the radioactive waste resulting primarily from the chemical processing operations for the recovery of plutonium and other defense strategic nuclear materials. The wastes are stored in hundreds of large underground tanks at four U.S. Department of Energy (DOE) sites throughout the United States. The tanks contain hundreds of thousands of cubic meters of radioactive and hazardous waste. Most of it is high-level waste (HLW), some of it is transuranic (TRU) or low- level waste (LLW), and essentially all containing significant amounts of chemicals deemed hazardous. Of the 278 tanks involved, about 70 are known or assumed to have leaked some of their contents to the environment. The remediation of the tanks and their contents requires the development of new technologies to enable cleanup and minimize costs while meeting various health, safety, and environmental objectives. While DOE has a process based on stakeholder participation for screening and formulating technology needs, it lacks transparency (in terms of being apparent to all concerned decision makers and other interested parties) and a systematic basis (in terms of identifying end states for the contaminants and developing pathways to these states from the present conditions). An End State Methodology for Identifying Technology Needs for Environmental Management, with an Example from the Hanford Site Tanks describes an approach for identifying technology development needs that is both systematic and transparent to enhance the cleanup and remediation of the tank contents and their sites. The authoring committee believes that the recommended end state based approach can be applied to DOE waste management in general, not just to waste in tanks. The approach is illustrated through an example based on the tanks at the DOE Hanford Site in southeastern Washington state, the location of some 60 percent by volume of the tank waste residues.