Release Estimation cont'd

DOE-HDBK-3010-94

7.0 Application Examples; Solid Waste Example

Even noncombustible waste will generally be mingled with combustibles, such as plastic bags

or tape, to some degree. The plastic pails can obviously burn along with whatever

combustible waste is inside them if an external heat source is provided. Internal heat sources

can generate fires as well. Procedure does not allow free-flowing liquid in the solid waste,

but liquids can be present in damp paper or other absorbents. Nitric acid-contaminated

cellulosic materials can spontaneously ignite, and if any trace moisture was present with

other trace waste such as calcium, an exothermic reaction could lead to ignition of

combustible material.

Generation of significant combustion inside sealed drums is much less likely due to close

packing and a limited oxygen supply. External fires will, however, result in pyrolization of

combustible material inside the drum. In normal room fire conditions, this will cause a slow

buildup of pressure that eventually fails seal joints resulting in emission of a torch flame

around the lid of the drum. If the drum contains highly volatile material and/or if the flames

are unusually intense with a high heat generation rate, the pressure buildup may be so rapid

that the drum lid pops off and some fraction of the waste is ejected from the drum.

7.3.9.2

Release Estimation

The potential energetic phenomena considered in this example are shock and impact to waste

containers and involvement of waste containers in fires.

A. Shock and Impact. For waste contained in taped plastic bags, very little release is

expected from any event that does not significantly deform or puncture the bag. For

waste in drums, the same expectation exists. In either case, if significant exposure of

the waste internals does not occur, whatever material might momentarily be jarred

airborne will be contained and filtered within the waste matrix. Estimating release

would be intrinsically related to the matrix leakpath factor, which is not large.

The maximum plutonium quantity allowed in a waste pail is 100 g, as initially

determined by a frisk reading at the point of generation and confirmed by subsequent

assay. The historical average for waste pails in general is 2 g. The maximum

amount of plutonium allowed in a waste drum is 200 g, with an historical average of

30 g.

Simply dropping a waste pail to the ground would not be expected to generate a

significant release for reasons already discussed. However, if the pail spills its

contents and the plastic bag deforms upon impact with a surface, some small release

is possible. For impact on contaminated solids that are unpackaged or lightly

packaged, the bounding ARF and RF are assessed to be 1E-3 and 1.0 (subsection

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