Research Needs for High-Level Waste Stored in Tanks and Bins at U.S. Department of Energy Sites Environmental Management Science Program (2001) / Chapter Skim
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2. Overview of HLW Challenges at DOE Sites
2. Overview of HLW Challenges at DOE Sites
Pages 13-27
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From page 13... ...
The current DOE estimate of the cost of converting these liquid and solid wastes into stable forms for shipment to a geological repository exceeds $50 billion to be spent over several decades (DOE, 2000~. The most important HLW sites in the United States are the followng: · the Hanford Site, near Richland, Washington, · the Idaho National Engineering and Environmental Laboratory (I N EEL)
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From page 14... ...
. Plutonium and uranium are extracted in the organic solvent while fission products and other impurities remain dissolved in the highly acidic aqueous nitric solution stored in tanks and classified as HLW.The fourth step consists of separating plutonium from uranium by reducing plutonium to the organic-insoluble, trivalent state while uranium remains in the organic phase in the oxidized form.
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From page 15... ...
HLW Management Strategy at DOE Sites The current DOE plans to treat and dispose of HLW face many technical uncertainties. Many of the planned treatment activities are first-ofa-kind efforts involving highly radioactive liquid and solid wastes.
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From page 16... ...
Spent nuclear fuel: Nuclear fuel that has been withdrawn from a nuclear reactor following irradiation, has undergone at least one year's decay since being used as a source of energy in a power reactor, and has not been chemically separated into its constituent elements by reprocessing. Spent nuclear fuel, through fission and neutron activation and decay, contains multiple radioactive elements with varying chemical and radiological properties.
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From page 17... ...
HEW Generation and Cleanup Strategies at DOE Sites The first HLW was generated at the Hanford Site from reprocessing reactor fuel for the production of plutonium used in nuclear weapons. The Yucca Mountain site in Nevada is currently under consideration as an HLW repository.
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From page 18... ...
Later efforts to recover uranium from the bismuth phosphate waste further changed the nature of HLW produced. The higher-activity liquid wastes from bismuth phosphate reprocessing were neutralized chemically to reduce their corrosiveness and stored in carbon steel underground tanks.
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From page 19... ...
The earliest tanks were single-shell tanks (SSTs) of carbon steel.
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From page 20... ...
A summary of the key facts and figures about the tank wastes at the Hanford Site is presented in Table 2.2. In its record of decision of 1997, DOE adopted a phased approach to tank waste management at the Hanford Site (DOE, 1997~.
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From page 21... ...
1.· Radionuclide Removal Sl edge l l Washing ~ Solid LLW Vitrification = Liquid HLW Vitrification ·h~ HLW Interim Storage O v e r v i e w o f H L W C h a I I e n 9 e s a t D O E S i t e s FIGURE 2.3 Based on information gathered from DOE, this figure represents a simplified view of the baseline plan for waste management at the Hanford Site. Closed Tanks · ·~ _= LLW Disposal Vaults Off-Site Transport
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From page 22... ...
The Idaho National Engineering and Environmental Laboratory Between 1 953 and 1 992, the I N EEL reprocessed spent nuclear fuel mainly for recovery of the fissile isotope uranium-235. In the reprocessing operation, spent nuclear fuel and its cladding materials (aluminum, zirconium, stainless steel, and graphite)
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From page 23... ...
Immobilized calcine and SEW will be stored temporarily on site awaiting eventual disposal in a geological repository. Figure 2.4 shows the proposed baseline plans for the management of HLW calcine and liquid at INEEL.
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From page 24... ...
. The HLW glass canisters produced are temporarily stored on site waiting for eventual disposal in a geological repository.
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From page 25... ...
From 1966 to 1972, commercial spent nuclear fuel was reprocessed at the WVDP to recover uranium and plutonium by a licensed, commercial fuel reprocessing plant. The reprocessed reactor fuel included a substantial quantity of typical light water reactor (LWR)
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From page 26... ...
2.4 million liters (0.66 million gallons) , after blending a small amount of acid waste into the alkaline waste 0.6 million curies (2.2 x 1 on becquerels)
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From page 27... ...
The 255 glass canisters produced are stored temporarily on site, awaiting eventual disposal in a geological repository. The WVDP is now performing final flushing of the tanks to prepare for shutdown of the waste melter.
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