ML24282B012
| ML24282B012 | |
| Person / Time | |
|---|---|
| Site: | PROJ0734 |
| Issue date: | 10/29/2024 |
| From: | Office of Nuclear Material Safety and Safeguards |
| To: | |
| Shared Package | |
| ML24282B009 | List: |
| References | |
| Download: ML24282B012 (1) | |
Text
Enclosure U.S. NUCLEAR REGULATORY COMMISSION SEPTEMBER 25, 2024, ONSITE OBSERVATION VISIT REPORT FOR THE SAVANNAH RIVER SITE SALTSTONE DISPOSAL FACILITY EXECUTIVE
SUMMARY
The U.S. Nuclear Regulatory Commission (NRC) staff conducted its 24th Onsite Observation Visit (OOV) to the Saltstone Disposal Facility (SDF) at the Savannah River Site (SRS) on September 25, 2024. This is the first SDF OOV in Calendar Year (CY) 2024 (SDF OOV CY-2024-01). On every OOV to SRS the NRC is focused on assessing the U.S. Department of Energy (DOE) compliance with the Performance Objectives (POs) in Title 10 of the Code of Federal Regulations (10 CFR) Part 61, Subpart C under Section 3116(b) of the Ronald W.
Reagan Defense Authorization Act for Fiscal Year 2005 (NDAA). The five 10 CFR Part 61 Subpart C POs are: §61.40 (General Requirement); §61.41 (Protection of the General Population from Releases of Radioactivity); §61.42 (Protection of Individuals from Inadvertent Intrusion); §61.43 (Protection of Individuals during Operations); and §61.44 (Stability of the Disposal Site after Closure).
For this OOV, the NRC focused on the monitoring areas and monitoring factors in the NRC SDF Monitoring Plan, Rev. 1 dated September 2013 (available via the NRC Agencywide Documents Access and Management System [ADAMS] at Accession No. ML13100A113), as supplemented by the six NRC letters from June 5, 2017, to October 18, 2021, (ML17097A351, ML18033A071, ML18107A161, ML18219B035, ML19150A295, and ML21279A173) to the DOE. This is the tenth SDF OOV under the 2013 SDF Monitoring Plan.
On July 1, 2024, the state of South Carolina implemented a regulatory reorganization, and the South Carolina Department of Environmental Services (SCDES) took over the South Carolina NDAA-Waste Incidental to Reprocessing activities from the former South Carolina Department of Health and Environmental Control, which was eliminated in the reorganization. SCDES staff participated in this OOV. The U.S. Environmental Protection Agency (EPA) Region 4 staff also participated in this OOV because, in the future, they will be involved in the final closure of the SRS Tank Farms.
Consistent with the NRC Guidance for this OOV dated September 3, 2024, (ML24248A046), the main activities conducted during this OOV were: (1) discuss operating and disposal structure status; (2) discuss the DOE plans for groundwater monitoring well locations; (3) discuss the draft NRC Monitoring Plan based on the 2023 NRC Technical Evaluation Report (TER) for the SDF; and (4) tour specific aspects of construction of Saltstone Disposal Structure (SDS) 11 and SDS 12. As a result of this OOV, the NRC did not close any of the monitoring factors in the 2013 SDF Monitoring Plan (as supplemented). In addition, the results of the OOV were consistent with the overall conclusions from the 2023 NRC TER for the SDF (ML23024A099).
1.0 ONSITE OBSERVATION VISIT ACTIVITIES On September 3, 2024, the NRC issued the OOV Guidance (ML24248A046) for the September 2024 SDF OOV (SDF OOV CY-2024-01). An OOV Guidance is a plan for what the NRC expects to cover during an OOV, which may be changed based on what happens during the OOV.
The OOV began with introductions and a short briefing on the agenda that was attended by representatives from the DOE (including the DOE contractors), the NRC, SCDES, and the U.S. EPA. The rest of the OOV consisted of technical discussions and a tour. The technical discussions were focused on operating and disposal structure status, the DOE plans for groundwater monitoring well locations, and the new draft NRC Monitoring Plan. The tour was focused on specific aspects of the construction of SDS 11 and SDS 12.
1.1 Technical Discussion - Operating and Disposal Structure Status 1.1.1 Observation Scope The technical discussion supported the NRC monitoring of the DOE disposal actions to assess compliance with the §61.41, §61.42 and §61.43 POs. The technical discussion was most relevant to the following monitoring areas and monitoring factors in the SDF Monitoring Plan, Rev. 1, as supplemented by the NRC letters to the DOE:
Monitoring Area (MA) 1 (Inventory) o Monitoring Factor (MF) 1.01 (Inventory in Disposal Structures) o MF 1.02 (Methods Used to Assess Inventory)
MA 8 (Environmental Monitoring) o MF 8.01 (Leak Detection)
MA 11 (Radiation Protection Program) o MF 11.01 (Dose to Individuals During Operations) 1.1.2 Observation Results The DOE presented an overview of the recent SDF operating and disposal structure status in the DOE presentation (SRMC-CWDA-2024-00060, Rev. 1) (ML24282B013). The key points from the technical discussion were:
Regarding the SDF worker doses:
o the SDF worker doses continue to meet the §61.43 PO o
reporting of SDF worker dose can now be distinguished from dose to workers in the Defense Waste Processing Facility Regarding the Saltstone Production Facility (SPF):
o in Fiscal Year (FY) 2023, the DOE processed 4,447,697 gallons of salt solution o
from January through August 2024, the DOE processed 3,287,543 gallons of salt solution o
the SPF is operating as necessary to support Salt Waste Processing Facility (SWPF) operations o
the DOE is working towards 24/7 operating capability, which is expected to occur in four shifts and to rely on direct transfers between the SWPF and SPF o
the DOE preparations for 24/7 operating capability include:
extended operating runs of up to 14 hour1.62037e-4 days <br />0.00389 hours <br />2.314815e-5 weeks <br />5.327e-6 months <br />s/day, which reduces flush water entering disposal structures maximum single day production of ~66,000 gallons of salt solution processed o
the option for direct transfers from the SWPF to the SPF has existed since March 2024 and the DOE has exercised that option approximately a dozen times Regarding the SDF right circular cylinder disposal structures:
o since the last SDF OOV, SDS 8 and SDS 9 were turned over to Operations o
see table below for status of disposal structures:
SDS Status 2A Initially received Saltstone in FY 2012 Contains ~2.8 million gallons of Saltstone Height of ~21.25 feet of Saltstone At fill limit and filled with Saltstone in FY 2014 2B Initially received Saltstone in FY 2012 Contains ~2.8 million gallons of Saltstone Height of ~21.25 feet of Saltstone At fill limit and filled with Saltstone in FY 2014 3A Initially received Saltstone in February 2017 Contains ~2.18 million gallons of Saltstone
~0.66 million gallons of Saltstone space remaining represents total capacity based on fill height of 21.25 feet fill height currently has Documented Safety Analysis fill limit of 17 feet 3B Initially received Saltstone in April 2022 Contains ~2.18 million gallons of Saltstone
~0.66 million gallons of Saltstone space remaining represents total capacity based on fill height of 21.25 feet fill height currently has Documented Safety Analysis fill limit of 17 feet 5A Initially received Saltstone in FY 2014 Contains ~2.8 million gallons of Saltstone Height of ~21.25 feet of Saltstone At fill limit and filled with Saltstone in FY 2017 5B Initially received Saltstone in FY 2014 Contains ~2.8 million gallons of Saltstone Height of ~21.25 feet of Saltstone At fill limit and filled with Saltstone in FY 2017 6
Initially received Saltstone in August 2018 Contains ~21.9 million gallons of Saltstone
~12 million gallons of Saltstone space remaining represents total capacity based on fill height of 41 feet 7
Initially received Saltstone in March 2022 Contains ~5.6 million gallons of Saltstone
~28.3 million gallons of Saltstone space remaining represents total capacity based on fill height of 41 feet 8
As of 09/15/2024:
Construction completed Turned over to Operations in April 2023 Has not received any Saltstone
~33.9 million gallons of Saltstone space remaining represents total capacity based on fill height of 41 feet 9
As of 09/15/2024:
Construction completed Turned over to Operations in January 2024 Has not received any Saltstone
~33.9 million gallons of Saltstone space remaining represents total capacity based on fill height of 41 feet 10 As of 09/15/2024:
Construction in-progress Pre-stressing and shotcrete in-progress Interior liner installations scheduled to start October 2024 11 As of 09/15/2024:
Construction in-progress High-Density Polyethylene (HDPE)/Geosynthetic Clay Liner (GCL) and Upper Mud Mat installation scheduled to begin in September 2024 12 As of 09/15/2024:
Construction in-progress Lower Mud Mat installation started in September 2024 HDPE/GCL installation scheduled to begin in October 2024 Upper Mud Mat installation scheduled to begin in November 2024 1.1.3 Conclusions and Follow-Up Action Items (FUAIs)
The NRC staff will continue to monitor the DOE SDF activities. The following FUAIs resulted from the technical discussion:
The DOE to provide to the NRC an update on any available SDS 6 and SDS 7 sump pump data (e.g., volumes removed, sample results) 1.2 Technical Discussion - DOE Plans for Groundwater Monitoring Well Locations 1.2.1 Observation Scope The technical discussion supported the NRC monitoring of the DOE disposal actions to assess compliance with the §61.41, §61.42 and §61.43 POs. The technical discussion was most relevant to the following monitoring areas and monitoring factors in the SDF Monitoring Plan, Rev. 1, as supplemented by the NRC letters to the DOE:
MA 8 (Environmental Monitoring) o MF 8.02 (Groundwater Monitoring) o MF 8.03 (Identification and Monitoring of Groundwater Plumes in the Z-Area) 1.2.2 Observation Results The NRC and the DOE discussed new information from the DOE about potential future groundwater monitoring well locations. The key points from the technical discussion were:
The information is not final because SDF well placement requires approval from SCDES and the DOE discussions with SCDES are ongoing In general, the DOE was amenable to installing wells in both the Lower Aquifer Zone (LAZ) and the Upper Aquifer Zone (UAZ) of the Upper Three Runs Aquifer (UTRA), as long as no wells provide a potential fast pathway through the Tan Clay Confining Zone (TCCZ)
The NRC and the DOE discussed differences between reported heights of the top of the TCCZ and resulting saturation of the UTRA-UAZ in different DOE reports:
o both Figure 3 and Figure 9 from the DOE document SRR-CWDA-2021-00065 (ML21217A082) that supported the SDF Performance Assessment (PA)
(ML20190A056), indicated that the water table is typically above the TCCZ (i.e., in the UAZ), near SDS 2B, SDS 3A, SDS 3B, SDS 5A, SDS 5B, SDS 6, SDS 7, SDS 8, SDS 9, SDS 11, & SDS 12; o
in contrast, during the OOV, the DOE provided a diagram that showed that wells near SDS 2B, SDS 3A, SDS 3B, SDS 5A, SDS 5B, SDS 6, SDS 7, SDS 8, SDS 9, SDS 11, & SDS 12 were unlikely to encounter water in the UAZ; o
during the OOV, the DOE indicated that potential future well ZGB-029D would be the most likely well to encounter water in the UAZ; o
the DOE attributed the difference to which well would be the most likely to encounter water in the UAZ to new information about the depth of the top of the TCCZ; o
the DOE indicated it would consider whether there would be implications for the DOE General Separations Area groundwater flow model and the SDF PA projections; o
in response to an NRC question, the DOE indicated it expected the zone of water table fluctuation to cover 3 meters (10 feet) (i.e., +/- 1.5 meters [5 feet] range in the depth to the water table); and o
the NRC indicated that it is important to be able to detect radionuclide transport in the UAZ, even if wells in the UAZ are dry in most years, because significant radionuclide transport can occur during wet years (e.g., as occurred with the historical release from SDS 4)
In response to an NRC question, the DOE indicated that water from hydrotesting is diverted to the Z-Area stormwater basins using both hoses and the existing drainage ditches The DOE indicated that all well locations are approximate and will be adjusted based on any surface and subsurface interferences The DOE indicated that it may not be possible to install well ZBG-029D downgradient of SDS 11, and may need to look at alternative locations near SDS 7 1.2.3 Conclusions and FUAIs The NRC staff will continue to monitor the DOE SDF activities. The following FUAIs resulted from the technical discussion:
The DOE to update the well numbers on Slides #53, #54, and #56 for DOE Presentation, Rev. 1 The DOE to provide to the NRC document K-ESR-Z-00014 (for SDS 10, SDS 11, and SDS 12) and equivalent documents for other disposal structures if not previously provided as part of the SDF PA references (e.g., K-ESR-Z-00009 (for SDS 8) and K-ESR-Z-00011 (for SDS 9))
The DOE to provide to the NRC photos of well cores from new SDF wells when installed as well as any additional descriptions of materials if recorded 1.3 Technical Discussion -Draft NRC Monitoring Plan 1.3.1 Observation Scope The technical discussion supported the NRC monitoring of the DOE disposal actions to assess compliance with the §61.41, §61.42, §61.43, and §61.44 POs. The technical discussion was relevant to all the monitoring areas and monitoring factors in the SDF Monitoring Plan, Rev. 1, as supplemented by the NRC letters to the DOE.
1.3.2 Observation Results The NRC thanked both SCDES and the DOE for their administrative and technical comments on the Draft NRC Monitoring Plan for the SDF, Rev. 2. Except for one DOE comment about the monitoring factors in Monitoring Area 9 changing since the 2024 NRC TER Appendix, the NRC made changes to the monitoring plan based on the comments provided by SCDES and DOE.
Both the DOE and SCDES did not have any questions on the technical discussion.
1.3.3 Conclusions and FUAIs The NRC staff will continue to monitor the DOE SDF activities. There were no FUAIs that resulted from the technical discussion.
1.4 Tour - Construction of SDS 11 and SDS 12 1.4.1 Observation Scope The tour supported the NRC monitoring of the DOE disposal actions to assess compliance with the §61.41 and §61.42 POs. The tour was most relevant to the following monitoring areas and monitoring factors in the SDF Monitoring Plan, Rev. 1, as supplemented by the NRC letters to the DOE:
MA 6 (Disposal Structure Performance) o MF 6.04 (Disposal Structure Concrete Fracturing) o MF 6.05 (Integrity of Non-Cementitious Materials)
MA 8 (Environmental Monitoring) o MF 8.01 (Leak Detection) 1.4.2 Observation Results The tour consisted of observing specific aspects of the construction of SDS 11 and SDS 12. The key points from the tour were:
Before the tour, brief instructions related to safety were provided The NRC staff observed specific features of the construction at SDS 11 and SDS 12, and, as requested by the NRC staff, the DOE took pictures of key features of construction of both disposal structures The NRC staff observed:
o the cross-section of the Lower Mud Mat for SDS 12, including wire mesh forms o
HDPE placed on the Lower Mud Mat of SDS 11; o
the GCL under the HDPE on the Lower Mud Mat of SDS 11; and o
preparations that the construction DOE had made to protect the edges of the GCL from the forecast rainfall (e.g., Hurricane Helene)
The DOE discussed with the NRC staff various construction techniques, including the management of HDPE (e.g., undulations), that the DOE faces when pouring the Upper Mud Mat The NRC planned to observe the DOE pouring of the Upper Mud Mat the next morning during the OOV; but, due to Hurricane Helene, the DOE decided to postpone the pouring until after the OOV.
During the tour, a DOE construction manager and others provided information on the phases of construction and construction features, including answering NRC staff questions 1.4.3 Conclusions and FUAIs The NRC staff will continue to monitor the DOE SDF activities. The NRC staff is interested in the HDPE/GCL composite barrier installations at future disposal structures. The following FUAIs resulted from the tour:
The DOE to provide to the NRC the photos from the Tour on 09/25/2024 The DOE to evaluate options to provide to the NRC the photos of HDPE management during placement of Upper Mud Mat placement at SDS 11 or SDS 12. (e.g., working out undulations, sweeping/clearing of HDPE, placement of outriggers) 2.0 OVERALL CONCLUSIONS 2.1 Overall Conclusions The information gathered during SDF OOV CY 2024-01 will be used for multiple NRC Technical Review Reports and future OOVs, based on the topics discussed. There is no change to the overall conclusions from the 2023 NRC SDF TER regarding compliance of DOE disposal actions with the 10 CFR Part 61 POs.
Background information can be found in the most recent NRC-issued Waste Incidental to Reprocessing (WIR) Periodic Monitoring Report (ML19058A272) dated October 21, 2019.
Please go to the NRC Public Website DOE WIR Location webpage for the SDF (https://www.nrc.gov/waste/incidental-waste/wir-process/wirlocations/saltstone.html) to see the current status of the NRC Monitoring of the SDF.
The NRC expects that the DOE will take into consideration the NRC staff information that was provided during the OOV.
2.1 Status of OPEN FUAIs from either Previous SDF OOVs or Calls All FUAIs from previous calls were closed prior to SDF OOV CY 2024-01. All but four of the FUAIs from previous SDF OOVs were closed prior to SDF OOV CY 2024-01:
SDF-CY21-01-001 - The DOE did provide the documents to the NRC; but the DOE needs to provide follow-up pictures and videos that were requested by the NRC. During SDF OOV CY 2024-01, the DOE indicated that the rest of the information was expected to be provided to the NRC in October 2024 with the issuance of the DOE document, SRMC-CWDA-2024-00004.
SDF-CY21-01-007 - The DOE will continue to provide the NRC with schedule updates on timing of HDPE/GCL installation and upper mud mat placement for future disposal structures. This FUAI will remain open until the DOE completes those activities. During SDF OOV CY 2024-01, both the NRC and the DOE agreed that this FUAI is still ongoing.
SDF-CY23-01-004 - During SDF OOV CY 2024-01, the DOE indicated that the information was expected to be provided to the NRC in October 2024 with the issuance of the DOE document, SRMC-CWDA-2024-00004.
SDF-CY-23-01-0006 - During SDF OOV CY 2024-01, the DOE indicated that the information was expected to be provided to the NRC in October 2024 with the issuance of the DOE document, SRMC-CWDA-2024-00004.
2.2 Summary of FUAIs Opened During this Onsite Observation Visit After the OOV, the NRC received the updated DOE OOV presentation (SRMC-CWDA-2024-00060, Rev. 1) (ML24282B013) pertaining to the activities during this OOV. The table below contains the FUAIs that were opened during SDF OOV CY 2024-01, including a unique NRC identifier for each FUAI:
Unique Identifier FUAI SDF-CY24-01-001 DOE to provide to NRC update on any available SDS 6 and SDS 7 sump pump data (e.g., volumes removed, sample results)
SDF-CY24-01-002 DOE to update the well numbers on Slides #53, #54, and #56 for DOE Presentation, Rev. 1 SDF-CY24-01-003 DOE to provide to NRC document K-ESR-Z-00014 (for SDS 10, SDS 11, and SDS 12) and equivalent documents for other disposal structures if not previously provided as part of the SDF Performance Assessment references (e.g., K-ESR-Z-00009 (for SDS 8) and K-ESR-Z-00011 (for SDS 9)
SDF-CY24-01-004 DOE to provide to NRC photos of well cores from new SDF wells when installed as well as any additional descriptions of materials if recorded SDF-CY24-01-005 DOE to provide to NRC the photos from Tour on 09/25/2024 SDF-CY24-01-006 DOE to evaluate options to provide to NRC the photos of HDPE management during placement of Upper Mud Mat placement at SDS 11 or SDS 12. (e.g., working out undulations, sweeping/clearing of HDPE, placement of outriggers) 3.0 PARTICIPANTS U.S. NRC U.S. DOE /
Contractors SCDES EPAR4 George Alexander Hawa Barry John Abernathy Jana Dawson Hans Arlt Greg Flach Hannah Herlong Jon Richards Harry Felsher Steve Hommel Justin Koon A. Christiane Ridge Terry Killeen Gregg O'Quinn Keith Liner Sheila Watts Joel Maul Rosemary Murphy Larry Romanowski Malcom Smith David Watkins Adam Willey
4.0 REFERENCES
U.S. Congress, Public Law 108-375, Ronald W. Reagan National Defense Authorization Act for Fiscal Year 2005, Section 3116, Defense Site Acceleration Completion, October 2004 U.S. Department of Energy (DOE), DOE-WD-2005-001, Rev. 0, DOE Draft Basis for Section 3116 Determination Salt Waste Disposal at the Savannah River Site, February 2005.
___, DOE-WD-2005-001, Rev. 1, DOE Basis for Section 3116 Determination Salt Waste Disposal at the Savannah River Site, January 2006. ML102850319
___, SRR-CWDA-2019-00001, Rev. 0, 2020 Performance Assessment for the Savannah River Site Saltstone Disposal Facility July 2020. ML20190A056
___, DOE Manual 435.1-1, Change 3, Radioactive Waste Management Manual, January 2021. ML21035A232
___, DOE Order 435.1, Change 2, Radioactive Waste Management, January 2021.
___, SRR-CWDA-2021-00065, Rev. 0, Response to NRC Request for Supplemental Information #8: Upper Three Runs Aquifer - Upper Aquifer Zone Lateral Flow Analysis, August 2021. ML21217A082
___, SRMC-CWDA-2024-00060, Rev. 1, Presentation for the NRC SDF Onsite Observation Visit on September 25, 2024, September 2024. ML24282B013 U.S. Nuclear Regulatory Commission (NRC), Technical Evaluation Report for Draft Waste Determination for Salt Waste Disposal, December 2005. ML053010225
___, NDAA-Waste Incidental to Reprocessing Monitoring Plan for the Savannah River Site Saltstone Disposal Facility, Rev. 1, September 2013. ML13100A113
___, Supplement to the 2013 NRC SDF Monitoring Plan, June 2017. ML17097A351
___, Supplement to the 2013 NRC SDF Monitoring Plan, March 2018. ML18033A071
___, Supplement to the 2013 NRC SDF Monitoring Plan, June 2018. ML18107A161
___, Supplement to the 2013 NRC SDF Monitoring Plan, October 2018. ML18219B035
___, Supplement to the 2013 NRC SDF Monitoring Plan, August 2019. ML19150A295
___, Technical Evaluation Report for the 2020 Performance Assessment for the Saltstone Disposal Facility at the Savannah River Site, April 2023. ML23024A099
___, Guidance for the September 2024 SDF Onsite Observation Visit, September 2024.