Management of Plutonium-Contaminated Wastes

DOE-HDBK-1132-99

Alamos that greatly reduces the amount of waste generated. Electrorefining is

used to purify plutonium, leaving impurities behind in an anode " eel"that

requires further processing, usually by aqueous means. Relatively pure

plutonium oxide can be reduced to metallic form by direct oxide reduction, which

requires dissolving plutonium oxide in a calcium chloride salt and introducing

metallic calcium as the reducing agent. The resulting calcium oxide can be

converted to calcium chloride by reacting with a chlorinating agent. Note that the

media for pyrochemistry are typically chloride salts, and require special aqueous

process equipment specifications to minimize corrosion. Likewise, the crucibles

used to contain the melt also should be processed into a waste form or

processed for extraction of plutonium. Exhaust ventilation, handling devices, and

local furnace cooling should take thermally hot operations into account.

Design of materials management and storage systems should attempt to achieve

inventory extension to the maximum extent possible; that is, to minimize the

frequency with which inventory must be taken and reconciled. This can be

accomplished by use of a vault system with a long-term storage vault that can be

locked down for a year or more, and a day vault that contains the items that will

be used within the year. Sizing of process equipment should recognize the

down-time required to complete inventory actions. These actions include

cleaning out process equipment, wiping down gloveboxes, consolidating

materials, conducting nondestructive assays, and reconciling inventory values.

Management of Plutonium-Contaminated Wastes . Plutonium-contaminated

and radioactive wastes generated from the PPHF should be managed and

handled safely and effectively. The process system should be designed to

minimize the generation of wastes at the source. The waste management system

should be designed to limit the release of radioactive materials to the

environment.

Process liquid waste should be collected in the liquid waste treatment system

and contained in geometrically safe vessels for temporary storage, sampling, and

neutralization. Liquid waste should be concentrated by evaporation, and off-gas

from the liquid waste evaporator should be sampled for radioactive materials and

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