Decontamination and Decommissioning Experience

DOE-STD-1128-98

Guide of Good Practices for Occupational Radiological Protection in Plutonium Facilities

material generated from decontamination activities (e.g., water and wipe material) must be

contained and disposed of as radioactive waste. For some locations, vacuuming the surfaces

may be appropriate. If vacuuming is used, HEPA-filtered vacuum systems are required to

keep airborne radioactive material out of the vacuum exhaust.

For some operations, periodic surface flushing with water may be adequate to maintain

acceptable contamination levels. Precautions should ensure control and collection of run-off

water so that material may be recovered and waste water analyzed before discharge.

Depending upon which isotope of plutonium is involved, geometrically safe containers may

be required for collecting and holding the liquid.

Depending upon the physical and chemical form of the plutonium and the type of surface,

plutonium may become imbedded in the surface. Removal of embedded material may

require physical abrasion, such as scabbling, grinding, sand blasting, or chipping, or it may

be accomplished using chemical etching techniques. If the surface is porous, complete

replacement could be necessary. The use of high-pressure water (hydroblasting) has been

quite successful for metal and concrete surfaces.

Ultrasonic cleaning techniques (electropolishing) or chemical baths may be useful for

decontamination of high-cost items if the chemicals used are compatible with the material to

be cleaned.

A description of different decontamination techniques is found in DOE/EV/10128-1, DOE

Decommissioning Handbook (DOE, 1980), and publications by Allen (1985) and the

Electric Power Research Institute (EPRI, 1989). The DOE Decommissioning Handbook

also includes guidance on decontamination techniques, assessment of environmental

impacts, disposition of wastes, and preparation of decommissioning cost estimates.

10.5 DECONTAMINATION AND DECOMMISSIONING EXPERIENCE

Considerable experience has been gained in D&D of commercial plutonium facilities, as discussed

in Hoovler et al. (1986), Denero et al. (1984), and Adams et al. (1982). Hoovler et al. (1986)

discuss the decommissioning programs carried out at two Babcock and Wilcox buildings in

Lynchburg, Virginia, which housed plutonium/uranium fuel development laboratories. They

include information on decommissioning and quality assurance plans, conducting D&D work,

performing radiological surveys before and after D&D work, and disposing of the waste. Denero et

al. (1984) discuss the D&D of the Westinghouse Nuclear Fuel Facility at Cheswick, Pennsylvania.

They describe the facility and its operations, nondestructive assay techniques, equipment required

for dismantling and packaging the waste, and management of the TRU waste. Adams et al. (1982)

discuss the complete D&D of the Westinghouse Advanced Reactors Division Fuel Laboratories at

the Cheswick, Pennsylvania, site. The report describes the D&D plans, the EA written for the

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