ML24051A181
| ML24051A181 | |
| Person / Time | |
|---|---|
| Site: | Vallecitos, Vallecitos Nuclear Center |
| Issue date: | 02/22/2024 |
| From: | Reactor Decommissioning Branch |
| To: | GE-Hitachi Nuclear Energy Americas |
| Shared Package | |
| ML24051A168 | List: |
| References | |
| EPID L-2023-LLA-0138 | |
| Download: ML24051A181 (6) | |
Text
Vallecitos Boiling Water Reactor License Termination Plan Request for Additional Information
Licensing Licensing RAI 1 - License Amendment Request
Basis:
The regulation in 10 CFR 50.82(a)(10) states that.the Commission shall approve the [license termination] plan, by license amendment, subject to such conditions and limitations as it deems appropriate and necessary and authorize implementation of the license termination plan.
Issue:
GEH did not address the evaluate whether or not a significant hazards consideration is involved with the proposed amendment as set forth in 10 CFR Part 50.92, Issuance of amendment.
Request:
Please provide your significant hazard consideration for this License Termination Plan (LTP).
Licensing RAI 2 - Submittal of Related Licensing Actions Basis:
Regulations in 10 CFR 50.82(a)(11)(ii) require that to terminate a license the Commission shall determine that -
The final radiation survey and associated documentation, including an assessment of dose contributions associated with parts released for use before approval of the license termination plan, demonstrate that the facility and site have met the criteria for decommissioning in 10 CFR part 20, subpart E.
Issue:
Section 5.0 of the LTP states that an exemption from 10 CFR 50.82(a)(11) requiring that the VBWR meet the requirements for release according to 10 CFR Part 20, subpart E, has been submitted, and that it includes a license amendment request to transfer the remaining VBWR facility and its in-situ residual radioactivity to the authority of the ESADA Vallecitos Experimental Superheat Reactor (EVESR) DR-10 license.
Request:
These additional licensing actions have not yet been submitted. As part of the license termination plan, please provide a schedule for the submittal of these additional licensing requests.
1 Technical Technical RAI 1 - Continuing Characterization
Basis:
The regulations in 10 CFR 50.82(a)(9) outline the requirements regarding the content and submittal of a license termination plan to the U.S. Nuclear Regulatory Commission (NRC) for approval, which includes a site characterization. Applicable guidance on site characterization and characterization surveys can be found NUREG-1757, NUREG-1700, Regulatory Guide 1.179, and NUREG-1575 (MARSSIM) that cover purpose, extent and methods.
Issue:
During review of Vallecitos Nuclear Center (VNC) Vallecitos Boiling Water Reactor (VBWR)
License Termination Plan (LTP), NRC will need sufficient site characterization information and data of the VBWR site to support evaluations needed for license termination and ensure a reasonable estimate of the level and amount of residual contamination that will be transferred to the ESADA Vallecitos Experimental Superheat Reactor (EVESR) license.
In the VBWR LTP, the licensee identified several areas and items remaining where characterization still should be conducted in order to support license termination evaluations, including post-vessel removal radiation surveys performed in previously inaccessible areas. At the time of this review, reactor vessel removal has been completed pursuant to 10 CFR 50.59.
Request:
a) Please confirm if post-vessel removal radiation surveys have been performed in previously inaccessible areas or describe when these are planned to be performed.
b) Provide a summary of the post-vessel removal radiation surveys or other additional characterizations to supplement the LTP.
c) Provide a list of any characterization activities still to be performed, if any.
Technical RAI 2 - Fractional Abundances
Basis:
Regulations in 10 CFR 50.82(a)(9)(ii) outline the required components of a license termination plan, which includes a site characterization. Applicable guidance on site characterization can be found in NUREG-1700 Section 2.2 and NUREG-1757 Vol.2, Section 4.
Issue:
VBWR LTP Section 2.3.2.1, Site Specific Radionuclides of Concern, states that smear/wipe samples collected during characterization surveys, described in Enclosure 3, SDR Radiological Characterization Report, TR-22-011 Revision 1, were analyzed for radionuclides and fractional abundances. Enclosure 3, Section 3.1, Radionuclides of Concern, gives additional information, stating that these samples consist of composited smear/wipe samples from both VBWR and EVESR. However, the licensees methodology for establishing fractional abundances does not appear to include a justification for how the calculated fractional abundances are representative of the VBWR site specifically.
2 In addition, in Table 3-4, Detected Radionuclides Comparison, of the Characterization Report, which in part, displays results from the samples sent to GEL analysis of ROCs and fractional abundances, includes H-3 and Cm-243/244 as detected above critical level. However, Table 2-9, VBWR Radionuclides of Concern and Fractional Abundance, of the LTP lists the fractional abundances of H-3 and Cm-243/244 as N/D.
Request:
a) Explain how the calculated fractional abundances are representative of VBWR specifically.
b) Explain the inconsistencies found in Table 3-4 as described above between the Characterization Report and LTP regarding fractional abundances.
Technical RAI 3 - Embedded Piping
Basis:
Regulations in 10 CFR 50.82(a)(9)(ii) outline the required components of a license termination plan, which includes a site characterization. Guidance on characterization and surveying of embedded piping can be found in DUWP-ISG-02 (ML23177A008) and NUREG-1757, Vol. 2, Rev. 2, Appendix G.
Issue:
VBWR LTP Section 2.4, Estimate of VBWR Radiological Inventory for Transfer to EVESR, contains information on penetrations and embedded piping as part of the discussion regarding the estimate of VBWR radiological inventory for transfer to EVESR. In each case, the LTP assumes that contamination levels inside the pipe are the same as the external contamination levels around it. For example, the LTP states that the contamination levels in 10 embedded pipes running from the containment building to the exterior Valve Pit is assumed to be the same as the contamination levels in the Valve Pit.
Request:
Provide justification of assumptions for embedded piping and penetrations contamination such that the valve pit contamination levels are representative of those inside the pipe, or how this aligns with current guidance on embedded piping.
Technical RAI 4 - Concrete Core Samples
Basis:
Regulations in 10 CFR 50.82(a)(9)(ii) outline the required components of a license termination plan, which includes a site characterization. NUREG-1700 Section 2.2 and NUREG-1757 Vol. 2, Rev. 2, Section 4.2.2 give additional guidance on what should be discussed in the site characterization portion of an LTP.
Issue:
3 VBWR LTP Section 2.1.4, VBWR Containment Concrete Core Samples makes the statement that No radionuclides other than Co-60 and Cs-137 were identified. All hard to detect (Ni-63, alpha emitters or transuranic radionuclides were identified. This statement is unclear and seems inconsistent.
Request:
Clarify this statement and explain if hard-to-detect radionuclides such as Ni-63, H-3, C-14, Sr-90, etc., were identified.
Technical RAI 5 - Remediation
Basis:
Regulations in 10 CFR 50.82(a)(9)(ii) outline the required components of a license termination plan, which includes plans for site remediation. Both NUREG-1757 Vol. 2, Rev. 2, Appendix N and Regulatory Guide 8.8, Rev. 3 (ML003739549) give specific guidance regarding ALARA principles.
Issue:
The VBWR LTP appears to contain inconsistent statements in several sections regarding site remediation activities. VBWR LTP Section 3.3 states that key areas will be evaluated and decontaminated as needed including the bioshield and external pump. Then, in Section 4.1, the VBWR LTP states that the bioshield will be remediated and the external ventilation system, spent fuel pool, and external pump will not be remediated based on current radiological readings and from an ALARA standpoint. Further on in Section 4.4, the VBWR LTP states that very little, if any remediation will occur.
More generally, the LTP states that areas will not be remediated from an ALARA standpoint, as noted in the paragraph above, but does not contain a discussion of the methods or ALARA analysis used to determine that these areas will not be remediated.
Request:
a) Clarify the inconsistent statements above and describe what areas have planned remediation, will not be remediated, or will be evaluated for remediation.
b) Provide the method used to determine if areas will be remediated or not from an ALARA standpoint.
Technical RAI 6 - Neutron Activation
Basis:
Regulations in 10 CFR 50.82(a)(9)(ii) outline the required components of a license termination plan, which includes a site characterization. Applicable guidance on site characterization can be found in NUREG-1700 Section 2.2 and NUREG-1757 Vol. 2, Rev. 2, Section 4.
Issue:
4 VBWR LTP Section 2.4, Estimate of VBWR Radiological Inventory for Transfer to EVESR, discusses the method used to estimate the types and quantities of radioactive material associated with VNC VBWR to be transferred to the EVESR license. In part, this includes an estimate of the neutron activation in the bioshield concrete using NUREG/CR-3474, Table 5.5 and reference [7] (D. W. James Consulting, "Vallecitos Nuclear Center VBWR Reactor Vessel and Internals Characterization and Classification - 2022," March 2022). However, there are no sample calculations and minimal discussion included on how the final estimates of 3.55E-11 Ci/g or 1.8 mCi were obtained.
Request:
Expand upon the methods used to estimate how the radioactivity in the bioshield associated with neutron activation was calculated. Include calculations or tables as necessary.
Environmental Environmental RAI 1 -
Basis:
In accordance with the requirements of 10 CFR 51.45(b)(1), information is needed in the Environmental Report (ML23261A593) to determine the scope of the review and provide a basis for staffs evaluation.
Issue:
In Section 1.1, Introduction, the Environmental Report (ER) states, It is the intent of GEH to decommission the Vallecitos Boiling Water Reactor (VBWR) at the VNC and terminate its Nuclear Regulatory Commission (NRC) license Developmental Power Reactor (DPR) -1.
Later in that same section, the ER states that For the VBWR license termination, the residual radioactive materials will remain under the Empire State Atomic Development Associates Incorporate Vallecitos Experimental Superheat Reactor license until it is terminated. In Section 1.3, Purpose, the ER states The purpose of this ER is to present a current evaluation of the actual or potential environmental impacts resulting from the preparation, removal, and disposal of the VBWR vessel. The vessel removal is the remaining component that is inseparable from the DPR-1 license.
Request:
Revise the scope of the proposed action and the resulting environmental impacts based on the request for supplemental information (RSI) response dated October 31, 2023 (ML23304A300). The ER should be updated to describe the proposed action, affected environment and environmental impacts for all resource areas. Based on RSI response, the reactor vessel removal has been completed under 10 CFR 50.59. Confirm that is no longer within the scope of the LTP review and update the ER accordingly.
5 This information is needed to determine the scope of the review and provide a basis for staffs evaluation. This information is required for compliance with 10 CFR 51.45(b)(1).
6