ML23251A212
| ML23251A212 | |
| Person / Time | |
|---|---|
| Site: | 07000925 |
| Issue date: | 10/02/2023 |
| From: | James Smith NRC/NMSS/DDUWP/URMDB |
| To: | Halliburton B Cimarron Environmental Response Trust |
| Shared Package | |
| ML23251A211 | List: |
| References | |
| Download: ML23251A212 (13) | |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 October 2, 2023 Bill Halliburton, Administrator Cimarron Environmental Response Trust c/o: Environmental Properties Management, LLC.
9400 Ward Parkway Kansas City, MO 64114
SUBJECT:
REQUEST FOR ADDITIONAL INFORMATION FOR THE SAFETY EVALUATION OF THE DECOMMISSIONING PLAN FOR THE CIMARRON SITE NEAR CRESCENT, OKLAHOMA (DOCKET NUMBER: 70-925)
Dear Bill Halliburton:
By letter dated October 7, 2022, (Agencywide Documents Access and Management System (ADAMS) ML22284A145), Environmental Properties Management, Inc. (EPM) submitted on behalf of the Cimarron Environmental Response Trust (CERT or licensee) a request for a license amendment approving CERTs proposed revised decommissioning plan. The U.S.
Nuclear Regulatory Commission (NRC) accepted the application for detailed technical review, as stated in a letter to EPM dated March 30, 2023 (ML23074A100). CERT also provided supplemental information in the area of criticality safety in a July 23, 2023, submittal (ML23205A179).
The NRC staff has identified areas where additional information is needed to complete its safety evaluation report for review of the revised decommissioning plan. Please see the enclosed request for additional information (RAI) and provide a response within 60 days of receiving this letter. We can also schedule a clarifying call if this would be of help to you in responding to this request. Because the NRC recently received the supplemental information provided by CERT with respect to criticality safety, RAIs for that area of the review will be sent separately by November 3, 2023.
In accordance with Title 10 of the Code of Federal Regulations 2.390 of the NRCs Agency Rules of Practice and Procedure, a copy of this letter will be available electronically for public inspection in the NRC Public Document Room or from the Publicly Available Records component of NRCs ADAMS. ADAMS is accessible from the NRC website at http://www.nrc.gov/reading-rm/adams.html.
B. Halliburton If you have any questions concerning this letter, please contact me at James.Smith@NRC.GOV or 301-415-6103.
Sincerely, Signed by Smith, James on 10/02/23 James A. Smith, Senior Project Manager Uranium Recovery and Materials Decommissioning Branch Division of Decommissioning, Uranium Recovery and Waste Programs Office of Nuclear Material Safety and Safeguards Docket No.70-925
Enclosure:
- 1. Request for Additional Information
- 2. Figures and Maps referenced in Enclosure 1 cc: Cimarron Site Service List
Cimarron Decommissioning Plan, Revision 3 Request for Additional Information, Group 1 (Groundwater Remediation & Modeling)
This Request for Additional Information (RAI) pertains to Section 8.0 of the License Application (Planned Decommissioning Activities)
GWRM-1 Description of the Issue Section 8.2, Groundwater Extraction and supporting documentation in Appendix K, Basis of Design (ML22308A076) indicate that extraction trenches proposed for the Transition Zone (TZ) in Burial Area 1 (BA-1) were designed and evaluated based primarily on the results documented in the 2018 Remediation Pilot Test Report (ML18171A300) rather than the groundwater flow modeling runs included in the 2022 Groundwater Flow Model Report (Appendix L; ML22308A183). The groundwater flow and particle transport modeling indicate limited capture associated with the extraction trenches using hydraulic conductivity (K) values of 3 feet/day up to 50 feet/day in the vicinity of the trenches. These K values are significantly higher than the < 1 foot/day values which most closely reproduce the results of the 2017-2018 remediation pilot testing results which effectively dried out the trench following 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> of pumping at approximately 16 gallons/minute (GPM). Although lower pumping rates of 7 GPM are proposed for each of the two extraction trenches (GETR-BA1-01 and GETR-BA1-02; 14 GPM total for both trenches) and injection trench GWI-BA1-04, located between the two extraction trenches, is proposed at 10 GPM of water injection into the TZ, it appears that the relatively low K values within the TZ will significantly limit the recovery and injection volumes for the trench system in BA-1 resulting in a limited capture zone footprint for the extraction system. Slug test data for TZ wells provided in the 2013 Hydrogeologic Pilot Test Report (ML20213C658) indicated six of the seven tested wells exhibited K values ranging from 0.0290 to 0.615 feet/day.
Basis of the Request Pursuant to Title 10 of the Code of Federal Regulations (10 CFR) Part 70.38 (g)4(ii),
the plan must include a description of planned decommissioning activities.
RAI Please provide an explanation as to why this is not a concern, or potential remedial alternatives or adjustments to the proposed system if the BA-1 trench extraction and injection system is unable to address the magnitude and extent of contamination within the TZ in a timely manner. Please summarize the types of in-process remedial data needed to evaluate potential system adjustments and the schedule for collection and review of these data during system operation. Please provide sufficient detail to allow Enclosure -1
staff to properly evaluate the proposed alternatives or adjustments to the remedial design.
GWRM-2 Description of the Issue Section 8.6.1, Groundwater Extraction Monitoring lists the in-process groundwater monitoring wells proposed for monitoring in both the BA-1 and Western Remedial Areas. Table 8-2 and Figure 8-8 list nine TZ groundwater monitoring wells in the vicinity of the two extraction trenches and injection trench GWI-BA1-04 within BA-1A remediation area. The proposed well network within the BA-1A area leaves noticeable areas of data gaps, particularly southwest of proposed extraction trench GETR-BA1-02 and extending to the southeast of existing extraction trench GETR-BA1-01 (see attached Figure 8-8). Given the complex, heterogeneous nature of the subsurface hydrogeology within the TZ, it is unclear how additional groundwater monitoring wells will not be required in order to properly evaluate the performance of the extraction/injection trench system within the TZ. It is unclear how the significant uncertainties regarding the hydraulic conductivity values within the TZ do not warrant a more robust groundwater monitoring network in the vicinity of the trenches. It is also unclear whether the additional groundwater monitoring wells in the TZ will be properly developed, gauged, and sampled for uranium and other appropriate analytes prior to system startup.
It is also unclear how the horizontal extent of the induced drawdown created by the trench system will be determined without the addition of existing monitoring wells to the east of existing extraction trench GETR-BA-1-01, particularly TMW-5, 02W10, and 02W09, to determine groundwater level elevations prior to and during the trench operations.
Basis Pursuant to Title 10 of the Code of Federal Regulations (10 CFR) Part 70.38 (g)4(ii),
the plan must include a description of planned decommissioning activities.
RAI Provide construction specifics, locational information, and the proposed monitoring schedule for any additional groundwater monitoring wells planned in light of the uncertainties outlined in the RAIs above. Consideration of the installation of nested monitoring wells with screen intervals isolated within lithologic zones of interest (sand interval(s) within permeable channel sand deposits; silt/clay deposits within saturated Upper Gully Fill/Lower Gully Fill (UGF/LGF) units) is recommended. The hydrologic responses of these isolated monitoring well screened intervals to injection and extraction in the BA-1A remediation area, as well as groundwater sampling analytical results, would provide valuable information on system capture and cleanup efficiency.
An updated Figure 8-8 and Table 8-2 would also be needed if additional wells are added.
GWRM-3 Description of the Issue The BA-1A remedial plan, included in Decommissioning Plan Version 3, primarily focuses on recovery and treatment of uranium contaminated groundwater in the shallow sandstone bedrock and the Transition Zone soils. The TMW-8 well, completed in Sandstone B and screened from approximately 10 to 24 feet below ground surface (BGS), is listed with a uranium concentration of 2,589 ug/L in the plan. Located upgradient of the Transition Zone area, this well represents the highest uranium concentration in a Sandstone B well in the BA-1 remediation area. As described in Section 8.4.1, Water Injection Trenches, of the Decommissioning Plan, Version 3, Injection Trench GWI-BA1-01 is in the southern portion of the former burial trenches, approximately 100 to 120 feet south of TMW-8, with Injection Trenches GWI-BA1-02 and 03 located to the west and northwest, respectively. Each trench is proposed for completion in the Sandstone B Unit. Based on the flow modeling results presented in Figure 4-3 of the Decommissioning Plan, only water injected from the GWI-BA1-01 trench travels through the TMW-8 hot spot area (see attached Figure 4-3). Evaluation of the groundwater flow model calibration data set and process presented in the 2022 Groundwater Flow Model Report (Appendix L; ML22308A183) indicates that overestimation of water level elevations in certain Sandstone B wells included in the calibration (1314; 02W50, and 02W52) and omission of the 02W51 well as a calibration point could have resulted in an underestimation of the easterly to east-northeasterly groundwater flow direction in the vicinity of Injection Trench GWI-BA1-01 (see attached Figure 3-2). Contoured groundwater flow maps of observed groundwater levels in the Sandstone B Wells from December 2012, March 2015, August 2016, and July 2020 (see attached Flow Maps 1 through 4) illustrate the accentuated easterly and east-northeasterly flow not captured by the flow model. This apparent discrepancy in the modeled groundwater flow and the resulting particle tracking, as well as the presence of preferential pathways north of the eastern portion of the injection trench (toward well 1409) noted in the 2018 Remediation Pilot Test Report (ML18171A300), may result in reduced effectiveness of the injection and flushing in the TMW-8 hot spot area that does not appear to have been addressed in the application.
Basis Pursuant to Title 10 of the Code of Federal Regulations (10 CFR) Part 70.38 (g)4(ii),
the plan must include a description of planned decommissioning activities.
RAI Please evaluate the potential implications of the flow model calibration and the preferential pathway issue on the design and operation of Injection Trench GWI-BA1-01 and the adjacent system components. Explain why, at a minimum, additional in-process monitoring points, including, but not limited to, Sandstone B wells 1409, TMW-20, 02W25, 02W51, TMW-2, and 02W50, are not necessary in the proposed groundwater monitoring locations in the Decommissioning Plan (see attached Figure 8-8 for the listed monitoring well locations). Monitoring for potential groundwater seeps during trench operation, particularly on the topographic slope east of the 1409 well, may be warranted based on the potential preferential pathway noted in area in the previous pilot test report. Also explain why Sandstone B Monitoring well TMW-18, located at the northern end of Injection Trench GWI-BA1-03 should not be included in the in-process groundwater monitoring locations.
GWRM-4 Description of the Issue The Decommissioning Plan, Version 3, does not include water level elevation or historical groundwater analytical data for vertical extent well TMW-17, screened within Sandstone C in the Transition Zone area (located close to Transition Zone1315R on the submitted site maps; see attached Geologic Cross Section in Figure 2-5). This monitoring point is well positioned in the BA-1A remediation area to provide confirmation that the injection activities in the Sandstone B injection trenches are not facilitating vertical migration of uranium contamination into the deeper water-bearing unit.
Basis Pursuant to Title 10 of the Code of Federal Regulations (10 CFR) Part 70.38 (g)4(ii),
the plan must include a description of planned decommissioning activities.
RAI Please provide the requested water level elevation and groundwater laboratory analytical data for the TMW-17 monitoring well. Please add the TMW-17 well to the in-process groundwater monitoring locations in the Decommissioning Plan or explain why doing so is not necessary. Less frequent monitoring of the vertical extent well may be appropriate if no significant impacts to the water-bearing zone are observed following an appropriate monitoring period of the injection operations.
GWRM-5 Description of the Issue Section 8.8, Post-Remediation Groundwater Monitoring, of the Decommissioning Plan, Version 3, does not include Sandstone B monitoring well TMW-8 or BA-1B alluvial monitoring well TMW-13 (see attached Figure 8-10 for well locations). The response of groundwater in the vicinity of both source area monitoring wells to the remediation activities is critical to an evaluation of the efficiency of the system. For this reason, TMW-8 and TMW-13 appear necessary for the in-process groundwater monitoring program. Likewise, confirmation of groundwater uranium levels remaining below NRC-license requirements in the post-remediation period is of equal importance.
Basis Pursuant to Title 10 of the Code of Federal Regulations (10 CFR) Part 70.38 (g)4(ii),
the plan must include a description of planned decommissioning activities.
RAI Please include the TMW-8 and TMW-13 wells in the post-remediation monitoring program for the BA-1 remediation area or explain why the inclusion of these wells is unnecessary.
GWRM-6 Description of the Issue The Decommissioning Plan Version 3 does not specify any reporting of remedial system construction, start up, operations & maintenance, or sampling/monitoring results to the NRC during site remediation. Periodic reporting to NRC of remedial progress, including reports summarizing remedial system operational parameters (system run time, individual well and trench flow rates, influent and effluent concentrations, total treatment volumes, resin status etc.) with tables and figures, including static and dynamic groundwater flow maps and uranium groundwater plume maps for each remediation area, are generally included as part of the decommissioning plan and requested at 6 months and one year following startup with annual reports requested thereafter. The first report generally includes a summary of the system startup activities and any pertinent information related to system functionality.
Basis Pursuant to Title 10 of the Code of Federal Regulations (10 CFR) Part 70.38 (g)4(ii),
the plan must include a description of planned decommissioning activities.
RAI Provide the plan for reporting of remedial progress, including the details summarized above, to NRC.
Health Physics/Radiation Safety Requests for Additional Information HP1- Clarification of what will remain onsite and require final status survey (FSS).
Description of the Issue Section 8.9 of the DP states that the WATF will remain onsite following the completion of groundwater remediation activities. The WATF Building will be subject to a final status survey after all equipment and material used for uranium treatment and spent resin processing, and all packaged LLRW have been removed. But Section 15.4 of the DP states that Within the licensed area, only the WATF building and the concrete slabs outside of the WATF building and in the BARF will remain on the Site. The WATF building is an asset to be transferred to a subsequent owner upon disposition of the property by the Trust. A final status survey plan providing a detailed description of the final status survey will be submitted to the NRC NRC staff needs to understand the rationale used by the licensee in the determination of what remains onsite after the completion of groundwater remediation activities and what will be subject to final status surveys to support license termination.
Basis This information is needed to determine compliance with the following requirements:
10 CFR 70.38(g)(1) procedures and activities necessary to carry out decommissioning not previously approved by the Commission.
10 CFR 70.38(g)(3)(vi) description of the planned final radiation survey.
RAI Please provide clarification as to what will remain onsite following the completion of groundwater remediation and license termination, and for those structures and slabs left behind, what will be subject to a final status survey.
HP2 -Clarify surveys associated with surface and subsurface soils.
Description of the Issue Section 12.5.2, Soil Disturbances, of the RPP (Appendix M to the DP) states that walkover gamma surveys will be performed to verify the net concentrations are at 30pCi/gm U or less for all disturbed soils and specifies that this applies to shallow excavations, foreign or suspect materials, soils removed from deep excavations, area graded for construction, well cores and 1206 Sediment. However, Section 13.1.3, Volumetrically Contaminated Materials, is the only part of the DP that mirrors this language and list, implying that the surveys will only be done as part of the process for identifying waste for shipment offsite. Surveys associated with disturbed soils are not mentioned at all in Section 15 of the DP and many sections of the DP talk about how the surface soils and subsurface soils either were released or are releasable.
Additionally, commitments for surveys of subsurface soils were made in previous versions of the DP (ML20094L181) and RPP (ML19154A597) that do not appear to be in the current DP.
NRC Staff needs to understand the circumstances under which soil and subsurface soil surveys will or will not be performed.
Basis NRC staff needs this information to be able to adequately assess the proposed program against the criteria of NUREG-1757 Volume 1 Revision 2 Section 16.4.3, Soils -
Radiological Status of the Site, 16.4.4 Subsurface Soils - Radiological Status of the Site and 17.1.3 Soils - Planned Decommissioning Activities.
RAI Please clarify survey methods to be used in radiological surveys of surface and subsurface soils that are disturbed during construction and decommissioning of the groundwater treatment equipment and facilities.
HP 3 -Justification for use of Class Y Uranium for internal dose assessment from inhalation.
Description of the Issue:
Discussion in Appendix A to the Radiation Protection Plan, Revision 5 states in Section 5.1 ALI for inhalation that all soluble uranium salts, like those present in the groundwater at the Cimarron site, are Type F which is equivalent to Class D used in NRC regulations but the comparison of ALI for inhalation is based on Class Y material.
There is no justification provided for this, even though Section 5.2. ALI for Oral Ingestion indicates that Class D Uranium for dose to bone surfaces is the limiting factor for internal dose. There also does not appear to be consideration for the fact that, due to the low enrichment, (modelled at 2.9% and 5% in Appendix A) for Class D uranium enrichments 10% or greater, the radiological dose is the limiting factor and below 10% enrichment, the chemical toxicity is considered the limiting factor for personnel exposure since an acute inhalation of 40 mg of Class D uranium can result in permanent renal damage.
Section 6.6 of the RPP, Internal Exposure Monitoring stated that internal monitoring is not warranted but later states if internal monitoring is needed, they will establish actions levels for intake based on chemical toxicity if soluble U is present, indicating that the licensee is aware of the chemical toxicity of the lower enrichment. This statement seems to conflict with the statement in Section 5.1 NRC needs to better understand the basis behind using Class Y for modeling inhalation dose at the low enrichment values. NRC needs to understand why the licensee would not establish uranium intake action levels based on chemical toxicity levels and performed internal dose estimates to support the decision to not conduct internal monitoring using Class Y while acknowledging Class D is present in the groundwater.
Basis NRC needs this clarification/justification to determine if the licensee has adequately addressed NUREG-1757 Volume 1 Revision 2 Criteria for Section 17.3.1.3 Internal Exposure Evaluation.
RAI Please provide a justification for the use of Class Y uranium for determining the dose from inhalation as modelled in Appendix A to the Radiation Protection Plan, Rev 5 that was provided as Appendix M to the Decommissioning Plan.
HP-4 Justify use of NUREG-1556 Volume 7 for RPP audit Description of the Issue The U.S. Nuclear Regulatory Commission (NRC) staff reviewed the Radiation Protection Plan included as Appendix M to the Decommissioning Plan Revision 3 submitted for approval on November 7, 20221 The purpose of the review was to ensure that the radiation protection program submitted to support decommissioning was compliant with the requirements for a special nuclear material licensee undergoing decommissioning and proposing the treatment of groundwater by collecting uranium-235 in resin beds.
NUREG-1556 Volume 72 is specific to limited scope academic or research and development licensees and does not seem appropriate for development of a radiation safety program for a facility that is proposing remediation of groundwater using resin beds and planning for the collection of uranium-235 (U-235). It should also be noted that Appendix H in NUREG-1556 Volume 7 is Considerations for Laboratory Animal and 1 NRC Agencywide Document Access and Management System (ADAMS) Accession No. ML22284A145 2 ADAMS Accession No. ML010370258 Veterinary Medicine Uses. It is much more likely that the reference was meant to be Appendix H to NUREG-1556 Volume 7 Revision 13 which is Sample Audit Program.
Volume 7 of NUREG-1556 suggests that a decommissioning plan includes the establishment of a radiation safety program that meets the requirements of 10 CFR 19, Notices, Instructions and Reports to Workers; Inspections and Investigations 10 CFR 20, Standards for Radiation Protection, 10 CFR 70, Domestic Licensing of Special Nuclear Material and 10 CFR 71, Packaging and Transportation of Radioactive Material as recommended in NUREG-1520, Revision 2, Standard Review Plan for Fuel Cycle License Applications.
Whereas NUREG-1556 Volume 17, Program-Specific Guidance About Special Nuclear Material of Less than Critical Mass Licenses - Final Report and NUREG-2212 (DRAFT) - Standard Review Plan for Applications for 10 CFR Part 70 Licenses for Possession and Use of Special Nuclear Materials of Critical Mass but Not Subject to the Requirements in 10 CFR part 70, Subpart H, also suggests a radiation safety program that meets the requirements of Parts 19, 20, 70 and 71, NUREG-1556 Volume 17 also includes the requirements of 10 CFR Part 37 as well as financial assurance, environmental monitoring, waste management and effluent monitoring requirements, and NUREG-2212 (Draft) also added 10 CFR 73.67 (in-transit requirements for SNM) and 10 CFR 21.21 (Notification of failure to comply or existence of a defect).
NRC staff needs to understand the rationale used by the licensee to limit the radiation safety program audit and to support the use of an audit checklist that was not specific to a license for possession of special nuclear material when special nuclear material audit guidance is available.
Basis:
This information is needed to determine compliance with the following requirements of Title 10 of the Code of Federal Regulations (10 CFR) Part 20.1101(a) which requires Each licensee shall develop, document, and implement a radiation protection program commensurate with the scope and extent of licensed activities and sufficient to ensure compliance and 10 CFR 20.1101(c) requires the licensee to periodically (at least annually) review the radiation protection program content and implementation.
RAI Provide justification for use of the Appendix H of NUREG-1556 Volume 7, Program-Specific Guidance About Academic, Research and Development, and Other Licenses of Limited Scope, Including Electron Capture Devices and X-Ray Fluorescence Analyzers 3 ADAMS Accession No. ML18065A006 as the guide for audit of the radiation protection program for this special nuclear material license to satisfy the requirements of 10 CFR 20.1101(c) as stated in Section 5.2 of Appendix M to the Decommissioning Plan, Revision 3.
- via email NMSS/DUWP NMSS/DUWP NMSS/REFS OFFICE R-IV/DNMS/MLDB
/URMDB /URMDB /ERLRB NAME JSmith JS MPoston-Brown MP KHayes KH LGuo LG DATE Sep 11, 2023 Sep 11, 2023 Sep 12, 2023 Sep 12, 2023 OGC/GCRPS NMSS/DUWP NMSS/DUWP OFFICE
/HLWFCNS/NLO* /URMDB /URMDB NAME ACoggins AC RVon RV JSmith JS DATE Sep 20, 2023 Oct 2, 2023 Oct 2, 2023