Soil-Contamination Considerations

DOE-STD-1136-2004

Guide of Good Practices for Occupational Radiation Protection in Uranium Facilities

10.2.4 Soil-Contamination Considerations

Depending on the activity levels found, locations where contaminated effluents have penetrated the

ground may require excavation during decommissioning. The facility design should minimize such areas.

Particular attention should be paid to storm runoff from roofs, storage areas, contaminated equipment

storage, and liquid waste treatment impoundments (including sanitary sewage systems if they may receive

some small amount of contamination during the life of the facility).

10.2.5 Other Features

Installed decontamination and materials-handling equipment that facilitates operation and

maintenance also generally facilitates decommissioning in two ways. First, it can be used for its intended

purposes of cle aning and moving equipment during the decommissioning phase. Even more important, it

usually contributes to a cleaner, better-maintained facility, where nonfunctional equipment is moved out

when it is no longer needed and work surfaces are kept free of spreadable contamination.

Other features include the following:

a. minimizing service piping, conduits, and ductwork,

b. caulking or sealing all cracks, crevices, and joints,

c. using modular, separable confinements for radioactive or other hazardous materials to preclude

contamination of fixed portions of the structure,

d. using localized liquid transfer systems that avoid long runs of buried contaminated piping,

e. using equipment that precludes the accumulation of radioactive or other hazardous materials in

relatively inaccessible areas, including curves and turns in piping and ductwork,

using designs that ease cut-up, dismantling, removal, and packaging of contaminated equipment

from the facility,

g. using modular radiation shielding, in lieu of or in addition to monolithic shielding walls,

h. using lifting lugs on large tanks and equipment, and

using fully drainable piping systems that carry contaminated or potentially contaminated liquids.

10.3 DECONTAMINATION AND DECOMMISSIONING PROGRAM REQUIREMENTS

The basic requirements for a D&D program at a DOE facility are found in Section 5 of

DOE O 435.1, Ch.1, Radioactive Waste Management. Planning for facility decommissioning shall be

initiated during the design phase for new facilities and before termination of operations for existing

operational facilities. DOE O 435.1, Ch.1, divides the discussion of requirements into several time periods:

pre-operational and operational activities, post-operational activities, D&D activities, and post-

decommissioning activities. Requirements for each of these time periods and for quality assurance are

presented in the following sections.

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