Event with Partial Collapse

DOE-HDBK-3010-94

7.0 Application Examples; Seismic Release Example

leakpath factor for the airborne surface contamination than would be the case for

static glovebox conditions.

The worst-case condition in terms of MAR is for the two plutonium peroxide feed

tanks (tanks 13 and 14) to be full (11,650 g Pu each) and to be the tanks that fail.

The release phenomena is conservatively estimated as a free-fall spill of 3 m or less.

As previously noted, these solutions are not considered concentrated heavy metal

solutions by the simple definition assigned in this handbook. The ARF and RF values

assessed to be bounding for free-fall spill of aqueous solutions are 2E-4 and 0.5

(subsection 3.2.3.1), making the initial respirable source term from such an event:

23,300 * 1.0 * 2E-4 * 0.5 = 2.3 g

C. 0.3g Event with Partial Collapse. For this event, two to four process solution

tanks are assumed to fail. The two tanks with the next largest MAR values are the

ion exchange eluate tanks (tanks 7 and 8), each of which can hold 5800 g by

flowsheet parameters or 6500 g by procedural limit. It would be very unusual to

have these tanks and the peroxide feed tanks full at the same time. The process

would be backed up because the destination of the ion exchange eluate tank material

as it exits the next process, eluate evaporation, is the peroxide precipitation feed

tanks. However, if this condition existed, the maximum initial respirable source term

for process tank failures increases to 3.6 g of plutonium.

The partial collapse assumption, however, entails significant additional damage to the

facility. This damage will be examined by major process, starting with the vessel

vent system. Significant plutonium accumulations are not present in the vessel vent

system. The hazard identification estimates were 30 g of plutonium in liquid form,

and from 5 to 20 g of plutonium as a solid in each of the three major tanks. It would

be conservative to consider the 30 g estimated as aqueous liquid that experiences a

free-fall spill with ARF and RF of 2E-4 and 0.5 (subsection 3.2.3.1).

The solid material is unlikely to spill as it is adhering to the raschig rings at the

bottom of the tanks, but that same adherence makes it an unlikely candidate for

shock-vibration release. The ARF and RF for this circumstance will be small. Given

the limited amount of material, the shock-vibration ARF and RF of 1E-3 and 1.0

(subsection 5.2.3.2) will be used solely for the purpose of proceeding with

computation. If 20 g of solid plutonium are assumed present in each tank, the

maximum initial respirable source term is:

(90 * 1.0 * 2E-4 * 1.0) + (60 * 1.0 * 1E-3 * 1.0) = 8E-2 g

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