This evaluation has been performed for the Caustic Waste Treatment System (CWTS) in Building
371 and is intended for any liquid wastes which currently exist or could be generated within the
facility. These wastes include liquids in bottles and tanks or from spills, maintenance, etc.
Activities within the scope of this evaluation include direct draining of tanks into the CWTS,
operation of the CWTS, and subsequent shipment of effluents to Building 374. The vacuum
source for the CWTS is the PROVE Vacuum System which was evaluated in NMSL-940110 and
thus will not be further addressed in this evaluation. Tasks such as material handling, drum
loading, spill response, etc., are conducted per building general comments and miscellaneous
limits. This evaluation was originally performed in accordance with procedure 3-B69-NSPM-5B-
01 and revised in accord with SSOC-NCSI-040.
In this revision, controls were added to allow caustic liquids to be received and filtered in the
The CWTS is a RCRA permitted treatment process which is designed to reduce fissionable
content of waste liquids to within discard limit for transfer to Building 374 liquid waste treatment
processes. Reference Appendix F for a flow diagram and room layouts of the CWTS. Waste
streams are fed into a manifold in glovebox 2401 via hardpiping, tygon tubing, or from other
sources, such as a "portable fill station" or four-liter bottle, and vacuum transferred to shielded
annular tanks D-2401 A/B/C/D where they are mixed, sampled, adjusted to 25 g Pu/l or less, and
transferred to clarifier columns T2411 A/B in glovebox 18 by use of pumps P2401 A/B in
glovebox 2402. A caustic in powder form, such as Magnesium Hydroxide, is added to the liquids
in these columns to neutralize the acidity and precipitate Pu out of the solutions. The contents of
the clarifier columns are then filtered through R6 filter FL2431 in glovebox 18 and the supernate
solution is collected in decant columns T2411 C/D, also in glovebox 18.
Plutonium Hydroxide precipitate from FL2431 is placed into nominal 2" high pans and passed to
glovebox 23 for drying on hotplate W-2. Dried material is placed into 8801 type cans, bagged
out, and managed in accordance with the appropriate limits, i.e. approved shipping container, cart,
etc. Used R6 filter media (pad) from FL2431 is dried in glovebox 18 and/or glovebox 23. The
dry filter media is then bagged out and managed in accordance with appropriate limits.
Supernate liquids in decant columns T2411 C/D are pumped by pump P2411 in glovebox 18
across either of two banks of 1 micron bag filters, i.e., FL2416-1,2,3 A/B in glovebox 2404, into
shielded annular tanks D-2402 A/B. Contents of these tanks are sampled and vacuum transferred
into shielded annular tank D-2403 if less than the Building 374 waste transfer limit of 4x10-3 g/l
fissionable material. If solutions do not meet the waste transfer limit, they are vacuum transferred
to tanks D-2401 A/B/C/D and reprocessed in the CWTS.