Liquid Waste - doe-std-1128-98

DOE-STD-1128-98

Existing storage and packaging requirements for plutonium metal and oxide are

addressed in DOE Order 460.1A (DOE, 1996b). The DOE's existing storage

practices for plutonium and plutonium-containing materials and wastes were

evaluated at a DOE Workshop in May 1993 [see Assessment of Plutonium Storage

Safety Issues at Department of Energy Facilities (DOE, 1994a)]. The draft

recommendations from this workshop for metals and oxides that are not in

containment vessels with certified hermetic seals [per ANSI N14.5 (ANSI, 1997a)]

are given in Table 8.3. The variety of plutonium-containing materials is illustrated

by the inventory information for the Hanford Site contained in documents by

Christensen et al. (1989) and Hoyt (1993).

8.4

LIQUID WASTE

Liquid waste from plutonium facilities includes various aqueous waste streams such as

cooling water, laundry waste, and floor-drain waste, and numerous organic and inorganic

chemical wastes. The design criteria and operational controls to make these streams

treatable and disposable, and the methods to treat them are beyond the scope of this

document and are highly facility-specific. General considerations are given below.

8.4.1

Design Objectives

If a facility process requires the generation of plutonium-contaminated liquids, it is

probably best to ensure that the mother liquid is demineralized water and that

plutonium is the only contaminant added. In this case, the liquid can be filtered,

demineralized, and recycled. Any other chemicals added to the water will

complicate treatment, increase the volume of secondary waste, and diminish the

opportunity for recycle. Organic contaminants such as oils, solvents, and detergents

will likely foul the ion exchange resin, greatly increasing resin volume.

A pure organic solvent has many of the advantages of demineralized water,

especially if it does not chemically degrade or evaporate under the conditions of

use. (Solvents are not usually amenable to purification by ion exchange; however,

filtration, extraction into aqueous solutions, and distillation are possible.)

Unfortunately, most organic solvents are classified as hazardous materials and any

material that comes in contact with them is likely to be a hazardous (or mixed)

waste when it is disposed of. If the solvent is combustible and the facility includes

an approved incinerator of sufficient capacity to handle the secondary waste, then

the organic solvents are highly desirable.

While such guidance may be helpful in facility design, there will be waste streams

that do not conform to either of the situations above. Most decontamination wastes,

laundry wastes, and floor-drain wastes are examples. In decontamination, it is

important that the process is selected with provisions to manage the waste. In many

cases, the nature of the facility determines that the waste will be a mixed waste. In

these cases, minimizing the volume is most important. For example, if a plutonium-

contaminated surface has been painted with a lead-based paint, the

decontamination waste will be mixed waste unless it is further treated to ensure that

the lead is not in a leachable form. In this example, removing the paint by dry ice

blasting, high-pressure water blasting, heat, or a similar method would be

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