Transfer of waste liquid to Building 374

DOE-STD-3007-93

value, i.e., typically 10-2 g/l Pu. However, in the event that upset conditions result in gram value

concentrations of fissionable material, i.e., greater than 7 g/l fissionable solution introduced into

the clarifier columns, failure to precipitate in the clarifier columns, and failure to use the R6 filter,

equipment in glovebox 2404 has been configured with geometrically favorable equipment and

large spacings such that subcriticality is maintained. Individual equipment is discussed as follows.

6.6.3 Bag-filters FL2416-1,-2,-3 (A/B): Each bag-filter canister is nominally 4.5" ID by 18" H

and is configured as shown in figure 2. Since minimum center-to-center spacing between filters

nominally ranges from 33 to 83 centimeters, bag-filter canisters are individually evaluated as

follows. The worst case physical configuration for an individual bag-filter canister is in contact

with four 4" D bag-filters (an extra is included in consideration of a limit violation). Per section

6.5.1, each bag filter contains at most 50 grams fissionable material. Accordingly, four bag filters

next to the bag filter canister would have a maximum fissionable mass of 250 grams which is less

than the minimum subcritical mass limit of 450 grams as referenced in TID-7016. 200 ml of

samples may be taken and handled as the small volume would not significantly affect reactivity.

6.7 Glovebox 2403: GB-2403 is located in room 1103. It is constructed of stainless steel with

0.25" lead and is nominally 15'long x 2'5" wide x 4'9" high. This glovebox contains two

maximum-size 1-liter pumps (P2403 A/B), one vacuum pick-up wand with fulflo filter FL2410,

and fulflo filter FL2411 installed on the return line from pumps P2403 A/B to tanks D-2401

A/B/C/D. Process sampler, ME-2404, is used to sample tanks D-2402 A/B. Samples are

collected and removed via sample drop. Bag filter FL-2422 does not require a filter from a

criticality standpoint, since wastes transferred to Building 374 have already been repeatedly

filtered. A standard SG-508 criticality drain is installed in GB-2403, thus flooding above a two-

inch depth is precluded. The vacuum pickup wand may be used for spills both internal and

external to GB-2403. Note that external spills may only be picked up with the wand if sample

analysis shows liquids to be less than 4x10-3 g/l Pu and U-235. These requirements are in place

to support double contingency of liquids transferred to Building 374.

In Appendix M the total volume of two pumps, two filter housings, three used fulflo filters, and

200 ml of samples in GB-2403 was estimated at 8.2 liters. Increasing the sample volume to 1000

ml will result in a total volume of 9 liters. This is clearly subcritical, even in a spherical volume,

for concentrations up to at least 250 g/l, as referenced in figure 32 of LA- 10860. This is a

reasonable upper bound since the highest concentration of Pu is less than 10 g/l in tank D-55B;

process tanks operated at a limit of 150 g/l; high-level Pu solutions are no longer generated in

Building 371, liquids are sampled as less than 150 g/l fissionable material before introduced into

the CWTS process, and solutions handled in this glovebox have been filtered through an R6 filter

and three 1-micron bag filters. Note also that full water reflection is only possible in the unlikely

event that the glovebox criticality drain becomes blocked. Thus it is asserted that equipment in

GB-2403 is subcritical for any credible contingency.

6.8 Transfer of waste liquid to Building 374:

6.8.1 Waste liquids which are transferred to tanks D-811 A/B must contain less than the Building

374 waste transfer limit of 4 x 10-3 g/l Pu + U-235 since these tanks are critically unsafe. Though

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