Release Estimation - h3010v10262

DOE-HDBK-3010-94

7.0 Application Examples; Feed Preparation Example

7.3.1.2

Release Estimation

The potential energetic phenomena are a powder spill, ignition of plutonium metal fines,

residue impaction, an air line rupture, and a criticality. Additionally, although there is no

clear mechanism for a significant fire in the room, one will be examined.

A. Powder Spill. The maximum allowed transfer unit (2000 g as Pu) is larger than

the individual batches prepared for dissolution in the feed preparation line (1000 g and

1322 g as Pu). This quantity could be present outside the glovebox in double

containers on a transfer cart or in the single inner container in the entry airlock to the

glovebox. The most likely place for a spill that could damage the can and discharge

its contents would be at the airlock, where the maximum potential fall height would

be ~ 1.3 m (4 ft). The DR for such an occurrence is assumed to be 1.0 (i.e., all

material spills).

If the material falls inside the can to the ground and the lid of the can is dislodged by

impact, the release is not really a free-fall spill. It is perhaps most appropriately

modelled as vibration or impact shock. For clumps of bulk powder, the bounding

ARF and RF are assessed to be 1E-3 and 0.1 (subsections 4.4.3.3.1 and 4.4.3.3.2).

The resulting initial respirable source term is:

2000 g * 1.0 * 1E-3 * 0.1 = 0.2 g

For the purposes of example, a case where the material falls freely through the air is

also considered. The ARF and RF assigned for a free-fall spill of powder of less than

3 m are 2E-3 and 0.3 (subsection 4.4.3.1.2). The initial respirable source term is:

2000 g * 1.0 * 2E-3 * 0.3 = 1.2 g

Alternatively, for free-fall spill the ARF may be determined based on the PSPILL

equation in subsection 4.4.3.1.2. Although subsection 4.4.3.1.2 only discusses

applying the PSPILL equation to fall heights greater than 3 m, it can be used for

smaller distances. The equation for bounding ARF is:

ARF = 0.2128 (Mo0.125)(H2.37)/

1.02

(7-2, 4-5)

where: ARF = airborne release fraction = 1.5E-4

Mo = Mass of powder spilled = 2 kg

H = spill height = 1.3 m, and

BP = bulk density of powder = 2,500 kg/m .

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