Operational Controls - STD-1128-98master0239

DOE-STD-1128-98

Guide of Good Practices for Occupational Radiological Protection in Plutonium Facilities

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 preferable to

sand blasting in which the sand would be added to form an additional mixed waste that

could require storage for many years.

Laundry wastes are a special problem because radioactive contamination, body oils, and

odors must be removed from protective clothing. For a time, dry cleaning was extremely

popular, because the solvents were easily redistilled and recycled. However, because the

solvents were usually chloroflorocarbons and because the small volume of waste generated

was mixed waste, this method is now rarely used. Incineration of disposable protective

clothing is an outstanding choice if an incinerator of sufficient capacity is available, but this

is rarely the case. Water washing is often the method of choice. In a few cases, plutonium

in the waste stream is removed adequately by filtration and the effluent can be disposed to a

sanitary sewer or to the environment under a National Pollutant Discharge Elimination

System (NPDES) permit. It is important to select a detergent for water washing that does

not foul or plug the filter and that has a minimal impact on ion exchange resins if they must

be used. Many household laundry detergents have fillers such as wood fiber to give them

greater bulk. These should never be used because the fiber has no beneficial use and will

end up as solid waste. As a general rule, extensive testing on clean material should be done

to optimize disposal of laundry waste.

Floor-drain wastes are much more of a problem in some facilities than in others. In some

facilities, there is a culture that says, "if you don't know what to do with it, pour it down the

floor drain." Such practices can lead to a mixture of water, detergent, oil, antifreeze, and

other substances that clog filters and foul ion exchange resins. In the worst cases,

solidification with Portland cement is the only alternative, and this increases an already large

volume. The use of catch basins under chemical and lubricating systems and extensive

training of personnel minimize the probability of such occurrences. Oil skimmers on floor-

drain collection tanks are sometimes advisable, as well.

8.4.2 Operational Controls

Once the facility is properly designed, training of personnel is the primary operational

control against generating excessive volumes of waste or against generating waste with

contaminants that interfere with treatment or change the classification.

Some facilities have used color codes to prevent materials from entering an area where they

will adversely affect waste management. For example, certain electronic contact cleaners

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