Event with Partial Collapse cont'd

DOE-HDBK-3010-94

7.0 Application Examples; Seismic Release Example

Contamination in piping can also generate airborne releases due to shock-vibration,

but these releases are also small for the process as it exists and are ignored in this

example.

The north half of the feed preparation glovebox contains the weighing and batching

and furnace stations. As previously noted in the examination of the 0.13g event,

these stations can hold up to 4000 g of plutonium as loose bulk powder. The

impactor station is in the north half of the glovebox as well, and it could be

processing as much as 1000 g of plutonium as residue contamination. In addition,

59 g of plutonium as loose surface contamination are also assumed in the glovebox.

The glovebox and residue surface contamination are assumed to release material due

to shock-vibration impact with an associated ARF and RF of 1E-3 and 1.0 (subsection

5.2.3.2). This is a very conservative assumption for the residue material, much of

which may not be amenable to release, and was not considered as available surface

contamination for the 0.13 g event. For example, plutonium metal in crucible

residues may be embedded in the pores of the crucible. Air current effects are

neglected because the material is routinely subject to forced draft ventilation.

The loose bulk powder experiences three release effects. The first is shock-vibration

of bulk-powder, for which the ARF and RF are 1E-3 and 0.1 (subsection 4.4.3.3.1).

The second is free-fall spill as the glovebox structure in the free-fall zone collapses.

The ARF and RF for this phenomena are 2E-3 and 0.6 (subsection 4.4.3.1). The

final release phenomena is air turbulence generated by the impact of debris. The

bounding ARF and RF for this phenomena are 1E-2 and 0.2 (subsection 4.4.3.3.2).

The initial respirable source term estimated is:

(1059 g * 1.0 * 1E-3 * 1.0) + [4000 g * 1.0 * (1E-4 + 6E-4 + 2E-3)] = 11.9 g

An additional release assumption that does not occur for the facility is specifically

examined for the feed preparation glovebox to demonstrate use of another release

fraction consideration. Suppose the plutonium charge can storage compartment and

one charge can outside the compartment awaiting transfer were located in the north

half of the glovebox as well. If each can contained a charge for the oxide dissolver,

8000 g of plutonium as oxide could be in the 6 cans in the holding compartment. An

additional 1320 g of plutonium as oxide could be in the can outside the holding

compartment.

This material is not loose bulk powder. It is contained, and thus will not experience

the full vibration and shock-impact effects that loose material experiences. It will not

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