Liquid Waste - STD-1128-98master0238

DOE-STD-1128-98

Guide of Good Practices for Occupational Radiological Protection in Plutonium Facilities

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

8-14