ML18337A404

Hanford Waste Management Area C Wir Evaluation Clarification Call Summary October 2, 2018

ML18337A404
Person / Time
Site:	PROJ0736
Issue date:	12/03/2018
From:	Lloyd Desotell Division of Decommissioning, Uranium Recovery and Waste Programs
To:
Desotell L
References
Download: ML18337A404 (4)

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Hanford Waste Management Area C WIR Evaluation 10-02-2018 DOE-NRC Teleconference Summary Department of Energy (DOE) Attendees: Sherri Ross (DOE-HQ), Jan Bovier (DOE-ORP)

Nuclear Regulatory Commission (NRC) Attendees: David Esh, Hans Arlt, Lloyd Desotell DOE Contractor Attendees: Marcel Bergeron (WRPS), Doug DeFord (WRPS), Sunil Mehta (INTERA), Matt Kozak (INTERA), Paul Rutland (WRPS), Keith Quigley (Veolia), Kent Rosenberger (SRR), David Thorn (Portage), Jim Field (WRPS), DJ Watson (WRPS)

Member of the Public Attendees: None The following topics regarding NRCs review of the Draft Waste Incidental to Reprocessing (WIR) Evaluation for Closure of Waste Management Area C (WMA C) at the Hanford Site were discussed during an October 2, 2018 teleconference. While the intent was for this teleconference be open to the public, the call in information was not posted on the following DOE Hanford webpage (https://www.hanford.gov/page.cfm/WasteManagementAreaC) prior to the call in time.

REMOVAL TO EXTENT PRACTICAL

1. The removal of key radionuclides from plugged pipelines was discussed. DOE stated that there is not a practical method to identify the locations where pipelines are plugged and are not intending to attempt to additional clear the pipelines beyond that already conducted during WMA C operations. NRC stated that additional detail regarding why no further action is practical may be needed.

2. The definition of key radionuclides when the simulated doses after closure are very low was discussed. NRC suggested DOE consider the intruder scenario when defining key radionuclides.

3. The removal of key radionuclides from tanks and ancillary equipment was discussed.

DOE stated that the focus was on the bulk waste removal rather than the use of technologies that target the removal of specific radionuclides. DOE stated that technology selection had to consider potential downstream impacts as discussed in Section 4.3 of the Draft WIR Evaluation (DOE/ORP-2018-01, Draft D). NRC stated that it may request DOE to provide additional details regarding the percent removal of key radionuclides for each unit (tank, piping, other ancillary equipment) that considers the phases (solid, liquid) that the key radionuclides are present in.

4. The apparent spike (increase) in removal efficiency at the end of the retrieval campaign for Tank 241-C-107, as shown in Figure 4-14 of the Draft WIR Evaluation, was discussed. DOE stated that the spike in the figure is simply the result of lowering the pump within the tank to remove the remaining waste.

DOE-NRC 10-02-18 WMA C 1lPage WIR Teleconference Summary

5. Waste retrieval results for tank C-108 were discussed. DOE stated that most of the waste was removed with DST AN-106 supernate. DOE stated that other supernates were not tried, as they cost millions of dollars and years of time. WIR evaluation Figure 4-17 was discussed with respect to the influence of risers on residual waste. DOE stated that installing new risers in a tank could cost up to 5 million dollars. DOE indicated that additional risers have been installed in some tanks to facilitate cleaning.

Chemical cleaning of Tank C-108 was discussed. DOE stated that the process used to terminate cleaning is presented it Section 4.3.3.8.2 of the WIR evaluation.

6. The effectiveness of chemical cleaning of Tank C-109, as presented in Figure 4-22 of the Draft WIR Evaluation, was discussed. NRC asked if the limit of technology had been reached for cleaning this tank. DOE indicated that the graphs show that the hold time (the time required to achieve sufficient chemical reaction) was sufficient. DOE stated that they relied on the experience and expertise of the engineers. NRC stated that their question about the chemical cleaning of Tank C-109 wasnt associated with hold time but with how many cycles of chemical cleaning.

7. The removal of waste from Tank C-110 was discussed. DOE stated that when the existing equipment could not mobilize waste the mobile retrieval tool (MRT) was deployed. DOE further stated that the MRT was not replaced after it developed a leak because waste retrieval was nearly complete. DOE indicated that the waste is friable and can be pushed by the MRT but is difficult to remove with the pumps.

8. NRC asked if a cumulative removal chart for Tank C-111 was available. DOE stated that a cumulative removal chart for Tank C-111 has not been developed. NRC stated that this information may be requested to demonstrate key radionuclides have been removed to the extent practical.

9. NRC asked if data were available that shows the initial and final solids volumes of each tank. DOE stated that, similar to the response to item 3 above, they focused on bulk waste removal and referenced Section 4.3.1 of the Draft WIR Evaluation. DOE stated that the information could be generated but it has not at this point.

10. NRC asked DOE to provide the rationale for the selection of particular technologies for removal. DOE stated the rational was presented in Section 4.3.1.1 of the Draft WIR Evaluation and RPP-PLAN-4015. Also, DOE will send NRC additional tank specific technology selection information.

11. NRC asked about the total annual operating budget for WMA-C. DOE stated that approximately 765 million dollars have been spent on operations at WMA-C over the course of 20 years, or on average $38 million/year.

WASTE CLASSIFICATION

12. The waste classification calculations presented in Section 6 of the Draft WIR Evaluation were discussed. NRC indicated that the waste classification concentrations provided in DOE-NRC 10-02-18 WMA C 2lPage WIR Teleconference Summary

10 CFR Part 61 included the assumption that not all waste would be disposed of at the waste classification limits. Therefore, if intruder doses were used to scale concentrations for a draft WIR evaluation the assumption shouldnt be included. DOE indicated that they based their approach on what was done for the Savannah River Site and that was formulated based on Appendix B of NUREG-1854. NRC stated that they (NRC) needed to review the consistency of approaches presented in NUREG-1854 (e.g., Appendix B) and that this topic should be revisited on a future call.

13. The grout formula DOE intends to use in the tanks and ancillary equipment was briefly discussed. NRC asked how DOE intends to incorporate the residual waste into a solid physical form if some of the waste is liquid. DOE stated that the grout design is not complete but that it will likely be similar to that used at other sites (e.g., SRS or INL) and that there may be a contingency to include additional dry cement if liquids are present in tanks. DOE indicated that free liquids are adsorbed during cement hydration reactions.

14. NRC stated that, for completeness purposes, the classification of all ancillary structures included within the scope of the Draft WIR Evaluation, including pits, diversion boxes, and plugged pipelines should be provided. DOE agreed.

15. NRC will review the information related to waste removal provided in this teleconference and determine whether additional follow-up is needed regarding 2009 NRC RAI comment #24 (Accession Number ML090090030).

Action Items Item Date Action Status Number 9-6.3a 9-6-18 NRC to provide GoldSim run log to DOE Completed 9-25-18 9-6.3b 9-6-18 DOE to provide NRC with GoldSim model for 400,000 Completed year simulation 9-27-18 9-6.5 9-6-18 DOE to provide additional details regarding the scaling pending for other uranium isotopes 9-6.6 9-6-18 DOE to provide the aqueous relative permeability pending parameters assigned in STOMP model 9-6.8 9-6-18 DOE to provide map showing the location of node 69 in pending relation to the tank footprint 9-6.9 9-6-18 DOE to provide a water budget table with inflow at the pending surface and inflow/outflow at the four aquifer boundaries 9-6.12 9-6-18 DOE to provide the simulated hydraulic heads from the pending STOMP model for the monitoring wells as seen in PA Fig. C-11, page C-22 9-6.14 9-6-18 Future presentation on Leapfrog geological model pending 9-6.15 9-6-18 DOE to check the discrepancy between 580 m3/d on PA pending

p. C-8 and 730 m3/d on p. C-12.

9.6.16 9-6-18 DOE to provide the simulated hydraulic heads from the pending CPGW model for the monitoring wells as seen in PA Fig. C-11, page C-22 DOE-NRC 10-02-18 WMA C 3lPage WIR Teleconference Summary

10-2.10 10-2-18 DOE to send information on tank specific retrieval pending technology selection information 10-2.12 10-2-18 NRC to check information in NUREG 1854 #12 pending 10-2.a 10-2-18 DOE to check public call in information posted on pending website.

Acronyms and Abbreviations DST double-shell tank DOE U.S. Department of Energy DOE-ORP U.S. Department of Energy Office of River Protection DOE-HQ U.S. Department of Energy Headquarters INL Idaho National Laboratory MRT mobile retrieval tool NRC US Nuclear Regulatory Commission PA performance assessment PNNL Pacific Northwest National Laboratory SRR Savannah River Remediation SRS Savannah River Site SST single-shell tank WIR waste incidental to reprocessing WMA waste management area WMA C Waste Management Area C WRPS Washington River Protection Solutions, LLC DOE-NRC 10-02-18 WMA C 4lPage WIR Teleconference Summary