Release Estimation - h3010v10323

DOE-HDBK-3010-94

7.0 Application Examples; Seismic Release Example

glovebox, the metal dissolving glovebox, the north half of the residue dissolving glovebox,

and the liquid sampling glovebox.

7.3.10.2

Release Estimation

The use of release fraction information for estimating seismic releases will be examined in

general. Possible release mechanisms will be considered for the 0.13g event, the 0.26g

event, and the 0.3g event assuming partial collapse of the facility.

A. 0.13g Event. As described in the hazard summary, this event will have little

substantial impact on process equipment or glovebox lines, even though it will do

some damage to structure internals. The majority of plutonium driven airborne will

come from vibration of uncontained plutonium powder or surface contamination. The

latter topic has been largely ignored in examples to this point because of the large

amount of process material involvement in the accidents examined.

The only process material that may be expected to release non-trivial amounts of

airborne plutonium are loose bulk powders exposed to the glovebox atmosphere

during the seismic vibration. In the feed preparation glovebox, a maximum of 2000 g

of loose bulk powder can be exposed in both the weighing and batching and furnace

stations. Another 1320 g of plutonium as oxide might feasibly be in a charge can in

the conveyor or on the glovebox floor. The can holding this oxide could tip over, but

the spring-hinged lid will not dislodge. To be very conservative, this phenomena

could be accounted for as well. It is more properly shock-vibration than free-fall spill

because no real spill in air or falling distance is involved.

Up to 2300 g of plutonium in peroxide cake can be exposed outside containers in the

precipitation line. This material is damp, but can be included if more conservatism is

desired. The containers in the calcining and hydrofluorination gloveboxes have

screw-on lids and are unlikely to be affected. Up to 2300 g of predominantly

plutonium oxide in the calciner may be sitting in the first-cycle dryer pan. The same

material may be being loaded into the calciner hopper at the precise moment the event

occurs and may spill. A maximum of 2000 g of plutonium as plutonium fluoride may

be sitting in a reduction crucible awaiting loading into the reduction furnace.

For all of the above to be happening requires considerable synchronicity between

operations and the seismic event. Even if it does, however, the resulting source term

is not large. The bounding ARF and RF values assessed for vibration-shock impact

of bulk powder on an unyielding surface are 1E-3 and 0.1 (subsection 4.4.3.3.1).

The bounding ARF and RF for free-fall spill of powder less than 3 m are 2E-3 and

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