ML24326A145

License Termination Plan Safety Evaluation Report

ML24326A145
Person / Time
Site:	Vallecitos Nuclear Center
Issue date:	11/27/2024
From:	Fuguet N, Harwell S, Jack Parrott Reactor Decommissioning Branch, NRC/NMSS/DREFS/FAB
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ML24348A094	List: ML24304B039 ML24305A081 ML24326A145
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Download: ML24326A145 (1)

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SAFETY EVALUATION REPORT BY THE OFFICE OF NUCLEAR MATERIAL SAFETY AND SAFEGUARDS RELATED TO APPROVAL OF THE LICENSE TERMINATION PLAN FOR THE VALLECITOS BOILING WATER REACTOR DOCKET NO.50-018 Date Contributors Nate Fuguet, NMSS Shawn Harwell, NMSS Jack D. Parrott, NMSS November 27, 2024

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1.0 INTRODUCTION AND BACKGROUND

1.1 Introduction By letter dated September 7, 2023 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML23250A267), as supplemented by letters dated September 15, 2023 (ML23261A591), October 31, 2023 (ML23304A300), and March 25, 2024 (ML24085A792)

GE Hitachi (GEH) submitted a license amendment request (LAR) to the U.S. Nuclear Regulatory Commission (NRC) to approve the License Termination Plan (LTP), under Title 10 Code of Federal Regulations (CFR) 50.82(a)(9), for GEHs Vallecitos Boiling Water Reactor (VBWR).

The NRC accepted the proposed LAR and LTP for review by e-mail dated October 31, 2023 (ML23307A089) and published a notice of consideration of the proposed LAR and a finding of no significant hazards consideration (NSHD) determination in the Federal Register on May 14, 2024 (89 FR 41996). The notice offered a 30-day comment period on the NSHD determination and a 60-day period to request a hearing or to petition for leave to intervene on the amendment request. No comments, hearing requests or petitions for leave to intervene were received.

In accordance with 10 CFR 50.82(a)(9)(iii), the NRC is required to hold a public meeting near the relevant site after the licensee submits an LTP so that NRC staff can discuss the NRC's review of the LTP. This meeting was announced with ads in the Tri-Valley Herald - Pleasanton, California, on May 15 and 16, 2024, and in the Federal Register on May 15, 2024 (89 FR 42510). The meeting was held on May 21, 2024, at the SpringHill Suites Pleasanton, Pleasanton, California. The Federal Register Notice also included a 60-day opportunity for the public to provide comments on the LTP in accordance with 10 CFR 50.82(a)(9)(iii). An NRC summary of that public meeting was issued on June 11, 2024 (ML24158A409) and includes a summary of questions from the public and the NRC staffs answers. No other public comments were received on the LTP.

1.2 Background

The VBWR is a boiling water reactor located at the Vallecitos Nuclear Center (VNC), in Sunol, California and is licensed as a power reactor under 10 CFR Part 50. The General Electric Company (GE) was issued a license by the Atomic Energy Commission (AEC) to construct and operate the VBWR on May 14, 1956. Developmental Power Reactor (DPR) license number 1 (DPR-1) was issued to GE on August 31, 1957, and full power was attained on October 19, 1957. The VBWR ceased operations on December 9, 1963, and was defueled on December 24th that same year. GE was issued a license to possess but not operate the VBWR reactor on September 9, 1965. The AEC issued GE an order to dismantle the VBWR on July 25, 1966, however, major dismantlement activities at the VBWR did not occur until the years 2007-2008 with the removal of most of the contaminated equipment and components. The reactor vessel, the last remaining component of the VBWR reactor, was removed from the VBWR reactor building and shipped offsite for disposal as described in the letter from GEH to NRC dated March 25, 2024 (ML24085A792).

The VBWR is co-located in an approximate 3.2-acre area within the larger VNC site referred to as the 300 Area along with the Empire State Atomic Development Associates Incorporated

[ESADA] Vallecitos Experimental Superheat Reactor (EVESR), license No. DR-10, which used the secondary plant and many of the support systems and structures originally built for, and licensed under, the VBWR.

2 VBWR License Condition 3a stipulates that the facility is to be possessed under the 10 CFR Part 50 portion of the license in the condition described in the Final Report on Deactivation of Vallecitos Boiling Water Reactor (Deactivation Report), dated February 5, 1965, (ML20028F477). The Deactivation Report includes details of certain equipment and facilities that were at that time transferred to the authority of the EVESR license. The VBWR license retained the following: 1) Reactor enclosure and contents; 2) Stack (since demolished); 3) Valve pit between the turbine and reactor buildings (pit located adjacent to the VBWR containment with piping and components having been removed); 4) Some wastewater and makeup water equipment and air lines (since removed for disposal); and 5) The reactor feed pumps and instrument air compressor located in the turbine building (since removed for disposal). Except for the VBWR ventilation system abutting the VBWR containment, no separate structures external to the VBWR reactor building remain under the authority of the VBWR license.

The VBWR facility, for purposes of this license amendment request, is therefore defined as the reactor enclosure, its contents, and remaining VBWR-specific plant components adjacent the reactor enclosure. In summary, the VBWR reactor enclosure, the VBWR valve pit, and the VBWR ventilation system, and associated residual radioactivity will be called the VBWR facility for purposes of this safety evaluation. All other residual radioactivity on the VBWR/EVESR 3.2 acre site area, whether from VBWR or EVESR operations, is, or will be, under the EVESR license.

Therefore, after completion of the transfer of the VBWR facility to the EVESR license, as described in the LTP, a final status survey plan (FSSP) that covers the VBWR facility, the EVESR facility and the 3.2 acre VBWR/EVESR area and addresses compliance with the radiological release criteria for license termination, will be submitted and reviewed as part of EVESR license termination request.

On October 22, 2007, license DPR-1 amendment 21 was issued, transitioning ownership of the VBWR from GE to GEH. By order dated April 25, 2024 (ML24039A011) the NRC approved the direct transfer of ownership of the VNC, including all NRC licensed facilities, from GEH to NorthStar Vallecitos, LLC (NorthStar Vallecitos). The sale of the VNC facilities from GEH to NorthStar Vallecitos is pending, and the NRC approved license transfer will not be effective until the transaction is complete.

1.3 VBWR Decommissioning Licensing Strategy As described in the VNC Decommissioning Limited Post Shutdown Decommissioning Activities Report (LPSDAR), dated September 21, 2022 (i), the VBWR licensee will request an exemption from 10 CFR 50.82(a)(11)(ii) that requires a licensed power reactor to meet the radiological criteria in 10 CFR Part 20, subpart E, in order to terminate the license. In support of that exemption request, the licensee must also transfer the remaining VBWR facility, and its in-situ residual radioactivity, to the authority of the EVESR license via license amendment. These actions for the VBWR decommissioning licensing strategy were first outlined in a GEH letter to the NRC, GEH Description of Process for Decommissioning the Vallecitos Nuclear Center Shutdown Reactors, dated November 11, 2021 (ML21315A005), and later described in the LPSDAR. Successful completion of this series of licensing actions will enable the VBWR license to be terminated and the final decommissioning of the VBWR building would then occur coincident with the final decommissioning and license termination of the EVESR facility. The termination of the EVESR license must be completed by April 15, 2030, in accordance with the

3 requirement in 10 CFR 50.82(a)(3) for power reactors to terminate their licenses within 60 years of the permanent cessation of operations.

2.0 REGULATORY EVALUTION In accordance with 10 CFR 50.82(a)(9), [a]ll power reactor licensees must submit an application for termination of license. The application for termination of license must be accompanied or preceded by a license termination plan to be submitted for NRC approval. The licensee has not applied for termination of the license at this time.

Under 10 CFR 50.82(a)(9)(i), the LTP must be a supplement to the final safety analysis report (FSAR), or equivalent. Since the VBWR does not have an FSAR or equivalent, this LTP was submitted as an equivalent document pursuant to 10 CFR 50.82(a)(9)(i). Therefore, once approved the LTP will serve as the license basis document for the review of any changes made to the LTP under 10 CFR 50.59.

In accordance with 10 CFR 50.82(a)(9)(ii), the LTP must include:

(A)

A site characterization; (B)

Identification of remaining dismantlement activities; (C)

Plans for site remediation; (D)

Detailed plans for the final radiation survey; (E)

A description of the end use of the site, if restricted; (F)

An updated site-specific estimate of remaining decommissioning costs; (G)

A supplement to the environmental report, pursuant to § 51.53, Postconstruction environmental reports, describing any new information or significant environmental change associated with the licensee's proposed termination activities; and (H)

Identification of parts, if any, of the facility or site that were released for use before approval of the LTP.

The LTP and associated supporting documentation state that they were developed following the guidance in NRC Regulatory Guide 1.179, Standard Format and Contents for License Termination Plans for Nuclear Power Reactors, NUREG-1700, Standard Review Plan for Evaluating Nuclear Power Reactor License Termination Plans, NUREG-1575, Multi-Agency Radiation Survey and Site Investigation Manual (MARSSIM), and NUREG-1757, Volume 2, Consolidated Decommissioning Guidance - Characterization, Survey, and Determination of Radiological Criteria.

Consistent with statements by the licensee about guidance used to develop the LTP, in conducting its review, the NRC used these guidance documents to review the VBWR LTP for approval under 10 CFR 50.82(a)(9):

Regulatory Guide (RG) 1.179, Revision 2, Standard Format and Contents for License Termination Plans for Nuclear Power Reactors (ML19128A067);

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NUREG-1700, Revision 2, Standard Review Plan for Evaluating Nuclear Power Reactor License Termination Plans (NUREG-1700) (ML18116A124);

NUREG-1575, Multi-Agency Radiation Survey and Site Investigation Manual (MARSSIM), Revision 1 (ML003761445); and, NUREG-1757, Consolidated Decommissioning Guidance, Volume 2, Revision 2 (ML22194A859).

Unless otherwise mentioned, these guidance documents provide an acceptable way for licensees to meet the requirements of 10 CFR 50.82(a)(9). Therefore, based on finding that an application is consistent with these guidance documents, the NRC is also able to conclude that the application satisfies the requirements of 10 CFR 50.82(a)(9).

The approval criteria for an LTP are given in 10 CFR 50.82(a)(10), which states:

If the LTP demonstrates that the remainder of decommissioning activities will be performed in accordance with the regulations in this chapter, will not be inimical to the common defense and security or to the health and safety of the public, and will not have a significant effect on the quality of the environment and after notice to interested persons, the Commission shall approve the plan, by license amendment, subject to such conditions and limitations as it deems appropriate and necessary and authorize implementation of the LTP.

Therefore, approval of the VBWR LTP will be by license amendment. Recognizing that there may be a need to make changes to the LTP following its approval by the NRC, the NRC staff is amending the VBWR license with this condition to allow the licensee to make certain changes to the approved VBWR LTP without prior NRC review or approval. The proposed VBWR License Condition 6 would read as follows:

6.

GE-Hitachi shall implement and maintain in effect all provisions of the approved License Termination Plan, submitted by letter dated September 15, 2023, as supplemented by letter dated March 25, 2024, as approved in License Amendment No. 22, subject to and as amended by the following stipulations.

NorthStar Vallecitos, LLC may make changes to the LTP without prior approval provided the proposed changes do not meet any of the following criteria:

(a) requires Commission approval pursuant to 10 CFR 50.59, (b) results in significant environmental impacts not previously reviewed, (c) detracts or negates the reasonable assurance that adequate funds will be available for decommissioning.

Based on its review of the VBWR LTP, as documented in this Safety Evaluation Report (SER),

the NRC has determined that it contains the required information, as described in 10 CFR 50.82(a)(9), in adequate detail to allow for LTP approval. In addition, the license condition that would be used to determine if changes to the VBWR LTP require NRC approval is appropriate for the scope of this LTP.

5 As described in 10 CFR 50.82(a)(9)(i), the LTP is approved as a supplement to the FSAR or equivalent. Since the VBWR does not have an FSAR or equivalent, the LTP was submitted as an FSAR equivalent document. Therefore, the LTP will serve as the license basis document for the review of any changes made to the LTP under 10 CFR 50.59. The NRCs approval of the LTP, as appropriate, is predicated on the site conditions as described in the LTP. If it is determined that a change is needed to the LTP, that change must be evaluated using the change criteria in the license condition approving the LTP to determine if the change needs prior approval from the NRC.

3.0 TECHNICAL EVALUATION

3.1 Introduction and Purpose The technical evaluation of an LTP assesses if the site characterization, remaining dismantlement and decontamination (D&D) activities, site remediation plans, FSSPs, and the determination of the radiological criteria for license termination are appropriate and adequate for the scope and content of the LTP. As stated in SER section 1.3, the scope of the VBWR LTP is limited because the licensee will seek a transfer of the VBWR facility to the license for the co-located EVESR facility. The LTP, in this case, essentially serves to provide sufficient information for the implementation of the transfer of the VBWR reactor building and residual contamination to the authority of the EVESR license. That transfer will then serve as the basis for the termination of the VBWR license. Therefore, certain categories of LTP information such as site characterization of the VBWR for the purpose of establishing radiological criteria for license termination and the FSSPs for the VBWR will be addressed in the EVESR LTP.

3.2 Characterization Chapter 2 of the VBWR LTP, Characterization, discusses the methodology and results of VBWR site characterization activities. Section 2.1, Site Characterization, discusses how the characterization of VBWR generally followed the MARSSIM process including a Historical Site Assessment (HSA) and scoping surveys, followed by characterization surveys.

Characterization continued during the removal of the reactor vessel with the overall goal of site characterization being to determine the nature and extent of residual contamination to support transfer of remaining residual activity to EVESR and VBWR license termination.

The LTP site characterization acceptance criteria in NUREG-1700 are:

The LTP identifies all locations, both inside and outside the facility, where radiological spills, disposals, operational activities, or other radiological accidents and or incidents occurred and could have resulted in contamination. This identification should be done on a room-by-room or area-by-area basis as necessary, including equipment, laydown areas, or soils (subfloor and outside area).

The LTP describes, in summary form, the original shutdown, and current radiological and non-radiological status of the site.

The LTP site characterization is sufficiently detailed to allow the NRC staff to determine the extent and range of radiological contamination of structures, systems (including sewer systems and waste management systems), floor drains, ventilation ducts, piping and embedded piping, rubble, ground water and surface water, components, residues, and environment, including maximum and average contamination levels and ambient

6 exposure rate measurements of all relevant areas (structures, equipment, and soils) of the site (including contamination on and beneath paved parking lots).

The LTP identifies the survey instruments and supporting quality assurance practices used in the site characterization program.

The LTP identifies the background levels used during scoping or characterization surveys.

The LTP describes in detail the areas and equipment that need further remediation to allow the reviewer to estimate the radiological conditions that will be encountered during remediation of equipment, components, structures, and outdoor areas.

3.2.1 Historical Site Assessment Section 2.1.2, Boundaries of the VBWR, defines the boundaries and components of the VBWR site in relation to the rest of the VNC site. The VBWR licensed facility is defined as the reactor enclosure and contents and all plant components outside of the reactor enclosure as discussed in Section 1.3 above. All reactor support systems inside the containment structure have been removed. The HEPA filter ventilation system and valve pit, located external to the containment, are to remain in-place and will be remediated during the EVESR license termination. The VBWR stack has been removed, accompanied by excavation and removal of associated ducting along the northeast area outside of containment. These components of the plant facility no longer exist as shown in LTP Figure 2-4, VBWR areas outside of containment.

Section 2.2 of the VBWR LTP, Historical Site Assessment, and its subsections provide a summary of the HSA (Enclosure 4 to the submittal dated September 15, 2024 (ML23261A596)),

done for the entire VNC site, including the VBWR. According to the HSA, the methodology used for the GEH VNC HSA is found in NUREG-1575 (MARSSIM). This includes the general criteria used to classify the survey areas as impacted or non-impacted. GEH considered all VBWR structures associated with the site as impacted.

The HSA reviewed available historical documents for events and circumstances that occurred during operating history of the facility that could have contributed to the contamination of the site environs above background level. VBWR LTP Table 2-6, HSA Identified Events Causing Contamination at VBWR, summarizes these documented events and circumstances. The HSA did not identify any new areas of potential residual contamination, not previously considered, within the boundaries of the VBWR.

In addition, the HSA documents interviews with current and former site personnel. VBWR LTP Section 2.2.1, Personnel Interviews, states that GEH selected these personnel based on their employment history at the site and included positions in maintenance, qualified reactor operators, and radiation protection. The licensee did not discover any undocumented events during this process.

3.2.2 2022 Site Characterization VBWR LTP Section 2.3.2, Radiological Characterization, and the following subsections specifically discuss the 2022 Radiological Characterization Report, Enclosure 3 to the submittal dated September 15, 2024 (ML23261A595), including the scope, methodology, survey instrumentation, and reference material used. The Site Characterization Plan guided

7 characterization activities, which used the MARSSIM Data Quality Objective (DQO) process to establish the necessary requirements and methods for obtaining characterization data. The licensee states that the scope of the Characterization Survey includes:

Identifying and quantifying the nature and extent of radiological materials Determining the distribution of radioactive material contamination in each area that contained radioactive materials contamination Obtaining data to provide guidance for waste management planning Providing information to support the development of site-specific Derived Concentration Guideline Levels (DCGLs)

Providing a decision-making basis for transfer of residual contamination to the EVESR license.

The NRC staff notes that this report describes the current radiological status of the entire VNC and includes areas outside of the VBWR license. Consequently, because the end goal of the VBWR LTP is to transfer residual radioactivity to the EVESR license for eventual license termination, development of DCGLs, and characterization in support of that, are outside the scope of VBWR LTP.

3.2.2.1 Methodology Section 2.3.2.3, Methodology, of the VBWR LTP describes survey development. GEH generated Design Package and Checklists (DPCs), packages for each survey unit utilizing Visual Sample Plan (VSP) Software (https://www.pnnl.gov/projects/visual-sample-plan). These are maintained at VNC and are available for review/inspection as needed. The licensee states that each survey package contains the following seven sections of information: (1) detailed description of the survey area, (2) photographs, drawing, or drawings of the survey area, (3) summary data from operational surveys or previous surveys, (4) characterization survey instructions-types and number of survey measurements and/or samples prescribed for the survey, (5) survey instrument requirements and any special tools, (6) health and safety requirements; and, (7) Radiation Work Permit (RWP) requirements. Section 3.4, Survey Design, of the Characterization Report discusses this methodology in greater depth. GEH developed these DPCs for each survey unit in accordance with MARSSIM guidelines and conducted survey unit assessments using the Data Quality Assessment process described in MARSSIM Chapter 8. The licensee collected duplicate samples/measurements at a minimum of 10% of total samples per survey unit. Duplicate sample results are used to assess the precision of the methods being employed, if necessary.

3.2.2.2 Radionuclides of Concern VBWR LTP Section 2.3.2.1, Site Specific Radionuclides of Concern, discusses the licensees anticipated radionuclides of concern (ROC) and fractional abundances. These are captured in Table 2-9, VBWR Radionuclides of Concern and Fractional Abundances. The section states that GEH analyzed select smear samples collected during the characterization survey and documented in the characterization report for important radionuclides, including hard-to-detect radionuclides (HTDs), to determine site ROCs and fractional abundances. In total, the LTP

8 states that GEH sent seven composite smear samples from VBWR and EVESR to GEL Laboratories, LLC for analysis.

In response to Technical RAI 2, GEH clarifies that they based calculated fractional abundances on smear samples collected from the VBWR during a 2019 characterization campaign in representative locations that exhibited higher levels of radioactivity. GEH states that smear data, as well as the method used for derivation of the distribution, will be included in an update to the LTP. The NRC staff notes that the response to Technical RAI 2 is adequate for the purpose and scope of the VBWR LTP review, but if the additional data and methodology listed above is not submitted as an update to the VBWR LTP, it should be included in a future EVESR LTP submittal to ensure a complete characterization determines the range and extent of radioactive contamination present on the site. (ML23261A595), SDR Radiological Characterization Report, TR-22-011 Rev 1, discusses the ROC and fractional abundance development process in more detail. ROCs identified from guidance documents NUREG/CR-3474, Long-Lived Activation Products in Reactor Materials, and NUREG/CR-4289, Residual Radionuclide Contamination Within and Around Commercial Nuclear Power Plants, were compared to those detected during characterization. These radionuclides were then narrowed down further considering half-lives and radioactive decay, and consideration of the 2019 source term reports to obtain an initial suite of ROCs. The ROCs, which the licensee provided in LTP Table 2-9, VBWR Radionuclides of Concern and Fractional Abundances, are shown in Table 1 below.

Table 1 - VBWR Radionuclides of Concern Radionuclide H-3 C-14 Ni-59 Co-60 Ni-63 Sr-90 Nb-94 Tc-99 Cs-137 Eu-152 Eu-154 Eu-155 Pu-238 Pu-239/240 Pu-241 Am-241 Cm-243/244

0 3.2.2.3 Instrumentation VBWR LTP Section 2.3.2.4, Survey Instrumentation, discusses survey instruments. The licensee selected instruments to provide detection capability for the suite of radionuclides expected to be present, including gross alpha and beta/gamma detection for surface measurements and gamma detection for personnel dose estimates, outside surveys, and building area dose rate measurements. Table 2-10, Characteristics of Selected Radiation Detection Instruments, displays a summary of survey instrumentation, radiations detected, detector type, calibration source, and use as employed during the scoping and characterization surveys. The section also discusses the methods for obtaining weighted instrument efficiencies by using guidance from NUREG-1507, Rev. 1 (ML20233A507), the radionuclide fractional abundance is multiplied by the detection efficiency for the radionuclide emissions and then by a surface efficiency. GEH derived alpha and beta efficiencies for the ROCs using data from NUREG-1507, Rev. 1, calibration curves for the Ludlum 43-93 detector. LTP Figure 2-7 and Figure 2-8 present the beta and alpha detection curves with energies required by VBWR ROCs.

GEH added four beta/gamma emitting radionuclides, Co-60, Nb-94, Cs-137, and Eu-152, to the curve developed in NUREG-1507, illustrating the VBWR ROCs. For these radionuclides, quantifying the beta activity is an appropriate means of quantifying total activity as the gamma emission accompanies beta decay.

The site-specific weighted total efficiencies for beta/gamma emitters and alpha emitters are presented in LTP Table 2-11, Site-Specific Ludlum 43-93 Total Efficiency for Beta Emitters, and Table 2-12, Site-Specific Ludlum 43-93 Total Efficiency for Alpha Emitters. For the VBWR alpha-emitting ROC, the alpha energy for Pu-238 did not fall within the original curve. GEH extrapolated its efficiency at the apparent asymptote at the same level as for Am-241.

The Site Characterization Report states in Section 3.3, Instrumentation, that the survey methods did not necessarily meet the MARSSIM recommended MDC of 50% of the screening criteria for statis surface measurements, due to both ambient and material background. NRC staff notes that this is acceptable for site characterization surveys with the goal of assisting in decommissioning planning, but that instrument and measurement techniques with adequate detection sensitivities should be used during FSS.

3.2.2.4 Reference Materials According to VBWR LTP Section 2.3.2.5, Reference Material, GEH obtained typical background disintegrations per minute (dpm)/100cm2 values for concrete and metal surface material from locations and representative materials considered to be unimpacted. GEH measured ten locations for both concrete and steel and displays values in Table 2-13, Reference Material Background Determinations, with application of the efficiencies discussed in SER section 3.2.2.3 to establish the counts per minute (cpm) values.

3.2.3 General Radiological Characterization Section 2.1, Site Characterization and its subsections discuss the general approach and methods of site characterization at VBWR. VBWR LTP section 2.1.3, Area 300 Surface Soil and Groundwater Samples, discusses soil samples and groundwater monitoring and sampling around the VNC 300 area. However, as discussed in the LTP, all outside environs for the 300 area, except for the VBWR sump and HVAC system and ducting, are included under the EVESR license. Therefore, surface soil and groundwater sampling fall under the boundary of the EVESR license and will be reviewed during EVESR license termination.

1 Section 2.1.4, VBWR Containment Concrete Core Samples, provides a description of 14 concrete core samples that GEH took from VBWR containment basement locations and on the basement level, as listed in LTP Table 2-4, Concrete Core Sampling Locations within Containment. The licensee collected the samples to a nominal 8-inch depth. GEH analyzed these core samples for gamma emitters at the VNC on-site radiochemistry laboratory. GEH identified Cs-137 in all the samples, and smaller quantities of Co-60 in many of the core samples. GEH analyzed three of the samples with highest results for full 10 CFR Part 61 radionuclide analysis and reported the results in LTP Table 2-5, Radiochemical Analysis of Selected Cores.

The VBWR LTP states that these results show [n]o radionuclides other than Co-60 and Cs-137 were identified. All hard-to-detect (Ni-63, alpha emitters or transuranic radionuclides) were identified. In response to RAI 4 (ML24085A792), the licensee clarified this statement and says, No hard to detects (Ni-63, alpha emitters, or transuranic radionuclides were identified.

3.2.3.1 Remaining Characterization VBWR LTP Table 2-8, Designation of Survey Areas for Characterizing VBWR, identifies areas and items remaining at the time of LTP submittal where characterization should be conducted to support the evaluations needed for the license termination. In addition, the licensee discusses performing characterization after reactor vessel removal in previously inaccessible areas to be used for final radiological characterization prior to VBWR license termination. In response to Technical RAI 1 (ML24085A792), GEH states that post reactor vessel removal surveys have been completed. GEH measured direct radiation levels. The dose rate inside the bioshield was less than 1 mRem/hr. GEH also collected smear samples and analyzed for gross alpha/beta activity levels, analysis for this loose contamination showed no detectable alpha activity and beta/gamma levels below 1,000 dpm/cm2. GEH also collected core samples of the bioshield at six locations that would have received the higher levels of neutron flux and resulting levels of neutron activation products, this is discussed further in Section 3.2.5 below. No additional samples or surveys are planned for characterizing the radioactivity inventory. Review of analytical results is on-going. The licensee states in response to Technical RAI-1 that the LTP will be updated to include the additional information on radiological conditions and updating the inventory for transfer to EVESR.

The NRC staff note that this RAI-1 response is adequate for the purpose and scope of the VBWR LTP review. However, if the additional data and methodology listed above is not submitted as an update to the VBWR LTP, it should be included in a future EVESR LTP submittal to ensure a complete characterization determines the range and extent of radioactive contamination present on the site.

3.2.4 Estimate of VBWR Radiological Inventory for Transfer to EVESR VBWR LTP Section 2.4, Estimate of VBWR Radiological Inventory for Transfer to EVESR, details the method used to estimate the types and quantities of radioactive material associated with VBWR that are to be transferred to the EVESR DR-10 License.

According to the LTP, data from the scoping and characterization surveys, along with subsequent follow up surveys in 2023, were used to estimate the types and quantities of radioactive material remaining for transfer to EVESR. Specifically, data from work packages documenting individual survey unit measurements were used. These Work Packages

2 summarize the radiological condition of the facilities prior to removal of the pressure vessel and are available at the site for inspection as part of the decommissioning records.

The LTP states that the Work Packages document the surface activity measured for the various survey areas. Measured values were used to determine the total surface activity for both alpha and beta/gamma activities (average values and percentages of total). The work packages included sketches that document the size of the areas measured. Table 2-14 provides a summary of the calculated total beta/gamma and alpha surface activity determined by multiplying the average activity (dpm/100 cm2) times the area of the object/area.

The licensee also considered penetrations and embedded piping. GEH assigned each of these a contamination level based on best estimates using relevant survey data from associated surfaces/areas. Some assumptions the licensee made include:

There are 10 embedded pipes from the containment building to the exterior Valve Pit: all sealed but with an assumed average diameter of 5 in and approximate length of 4 ft from the inside of containment to the inside of the Valve Pit. The total pipe area is 56 ft2.

GEH assumed the contamination level in the pipes to be the same as in the valve pit.

There are 10 penetrations near grade of the containment building ranging from 6 to 18 in diameter; there are 135 individual pipes (electrical conduit, air lines, etc.). GEH assumed each to be 0.5 ft long for a total area of 52 ft2 and assumed the contamination level on the main floor to be the same as within these pipes.

In response to technical RAI 3 (ML24085A792), GEH expanded upon their discussion of characterization of penetrations and embedded piping and stated that all of these pipes are to be remediated during the decommissioning of EVESR and additional radiological characterization will be performed at that time. NRC staff finds the licensees assumption adequate that the inside contamination based on source and endpoint measurements is reasonable for the purpose of quantifying total activity for transfer to EVESR but notes that proper characterization and remediation of the pipes should occur during EVESR license termination.

For surfaces, as discussed above, the total beta/gamma or alpha activity is measured by average surface contact readings using a Ludlum 43-93 radiation detector corrected for the weighted detection efficiency. To provide a conservative estimate, the licensee made several assumptions regarding the entries in Table 2-14:

Surface contamination penetration is generally limited to the top 0.1 cm. Scan and static measurements will primarily reflect surface (or near surface) activity levels due to the limiting transmission/penetration for betas and alphas. This surface effect is reflected in the source geometry factor included in the instrument efficiency determination. The measurements of surface contamination in dpm/100cm2 have been converted to an estimated total volume activity level, considering the assumed depth (0.1 cm) and instrument efficiency for the ROCs.

Bioshield concrete radioactivity can be attributable to neutron activation. Neutron activation levels of BWR bioshield concrete are given in Table 5.5 of NUREG/CR-3474 for several depths up to 60 cm in the bioshield for 30 Effective Full Power Years (EFPY).

GEH adjusted these levels to reflect the VBWR operating history of 1.1 EFPY. The

3 resulting estimate of activation activity for the VBWR bioshield is 3.55E-11 Ci/g, accounting for decay since shutdown. For an assumed depth of 60 cm for activation products and given the bioshield dimensions and density, the calculated activation activity is 1.8 mCi, with an alpha component of 0.0014 mCi (based on the ratio of alpha to beta/gamma component in NUREG/CR-3474).

The Work Packages identified several auxiliary structures, such as grating and stairs, inside the containment building. In general, the contamination levels of such surfaces are considered lower than the surrounding building surfaces. The total area associated with such structures is a small fraction of the total surface area associated with the buildings. As a bounding estimate, the radioactivity associated with the main and basement floor areas have been increased by a factor of 1.1 to address the potential additional radioactive materials for these auxiliary structures.

According to GEH, each of the above-assumed factors is reasonably conservative based on knowledge of the facilities. The identification of the survey units and the correlation of average contamination levels to radioactivity inventory are presented in LTP Table 2-14, VBWR Radioactivity Inventory to be Transferred, which is replicated in its entirety below.

Table 2 - Estimate of VBWR Radioactivity Inventory to be Transferred In response to Technical RAI 6 (ML24085A792), GEH expands upon the discussion of the estimation of neutron activation in the bioshield. In addition to an initial estimate using values of activation levels in VBWR bioshield concrete from NUREG/CR-3474, adjusted to reflect VBWR operating history of 1.1 effective full power years (EFPY), GEH collected core samples of the bioshield at six locations for the purpose of evaluating the neutron activation component and sampled twelve locations reflecting the upper, middle, and lower core region. The samples represented a 4.5-inch depth core; GEH extracted the inner 1-inch and outer 1-inch segments to allow evaluation of depth of activation. The licensee then counted these segments on-site by gamma spectroscopy. From these twelve (12) segments, GEH analyzed five (5) for 10 CFR 61 identified transuranics and other HTD radionuclides. GEH detected low levels of Ni-63, Co-60,

4 Sr-90, Cs-137, Eu-152, and Eu-154 in the 10-6 to 10-4 Ci/g range but did not detect any transuranics. GEH states in response to Technical RAI-6 that the VBWR LTP will be updated to include the additional information on radiological conditions, describe the methodology for calculating the bioshield inventory, and an updated radioactive material inventory for transfer to EVESR.

NRC staff notes that this RAI 6 response is adequate for the purposes and scope of this review but notes that if an update to the VBWR LTP is not submitted, the EVESR LTP should contain a complete characterization of the residual radioactivity in the VBWR building, including the information listed to be submitted above, to determine the extent and range of radiological contamination at the EVESR facility. The total residual radioactivity associated with the VBWR proposed to be transferred to the EVESR DR-10 license, at the time of this LTP submittal, is estimated to be 10.8 millicuries. The VBWR LTP states that complete radiation surveys in remediated areas, updated characterization data, and additional information, will be used to update estimates of residual radioactivity remaining as needed for supporting the transfer of residual radioactivity to the EVESR license and the request for an exemption from 50.82(a)(11)(ii).

3.2.5 NRC Evaluation of VBWR Site Characterization The NRC staff reviewed the information in the VBWR LTP for the VBWR site, Enclosure 3, SDR Radiological Characterization Report, and Enclosure 4, VNC Historical Site Assessment, in accordance with NUREG-1700, Section 2.2, Site Characterization. As described in NUREG-1700, the purposes of the NRC staffs review are: (1) to ensure that the site characterization presented in the LTP is complete; and, (2) to verify that the licensee obtained the data using sufficiently sensitive instruments and proper quality assurance procedures to obtain reliable data that are relevant to determining whether the site will meet the decommissioning limits if characterization data is used as final survey data. The areas of review for NUREG-1700 Section 2.2 states that the LTP should: (1) identify all locations where activities (including spills) could have resulted in contamination; (2) summarize the status of the site; (3) be sufficiently detailed to allow a reader to determine the contamination levels; (4) identify survey instruments and practices; (5) identify background radiation levels; and, (6) describe areas and equipment that need further remediation.

The licensee has sufficiently detailed the status of the VBWR facility to preliminarily determine the extent and range of radiological contamination in the structures. NRC staff notes that while soil and groundwater characterization is included in the LTP and Site Characterization Report, it is not within the scope of this review and license termination. Soil and groundwater will be discussed and remediated, as appropriate, as part of the EVESR license termination.

The NRC staff evaluated the licensees radiation detection and measurement instrumentation used to perform site characterization in accordance with the regulatory guidance and areas of review contained in NUREG-1757, Volume 2, Revision 1, Section 4.2, and NUREG-1700 Section 2.2. The NRC staff attempted to verify the static and scan MDCs for the Ludlum 43-93 in the table using the data in subsections of 2.3.2.4 of the LTP and section 3.3 of the characterization report. The licensee did not include the equations and methods used to calculate MDCs, along with a detectability index, d, for the scan MDC. NRC staff found the static MDCs for the Ludlum 43-93 to be reproducible, and the scan MDCs, while not reproducible based from given values, were close to, and more conservative than, NRC staff calculated values. The NRC staff finds that the proposed radiation detection and measurement instrumentation for performing characterization was consistent with the NRCs guidance and

5 requirements. As such, the NRC staff finds that the licensees characterization instrumentation was adequate to demonstrate compliance with 10 CFR 50.82(a)(9)(ii)(A) and 10 CFR 20.1501(a) and (b).

NRC staff reviewed the VBWR LTP for the identification of major radiological contaminants (radionuclides of concern) and methods for addressing HTDs in accordance with areas of review contained in Section 2.5 of NUREG-1700. The licensee established fractional abundances for all ROCs, including HTDs, through full suite analysis of representative samples.

Methods for addressing HTDs, such as surrogate ratios, are not required because VBWR will be requesting exemptions from 10 CFR 50.82(a)(11)(ii), requiring that the VBWR meet the requirements for release according to 10 CFR Part 20, subpart E. Because VBWR residual activity is proposed to be transferred to the EVESR license and the licensee intends to request an exemption from 10 CFR 50.82(a)(11)(ii), which requires that the VBWR meet the license termination criteria of 10 CFR Part 20, subpart E, there is no discussion of insignificant contributors as they will be addressed during EVESR license termination. The NRC staff reviewed the licensees estimate of VBWR radiological inventory for transfer to EVESR, along with the associated RAI responses, and finds that because the licensees instrumentation, identification of major radiological contaminants and characterization methods for total residual activity estimation were adequate, the licensees estimate is reasonable for the purpose of this LTP as it provides information for quantifying total activity for transfer to EVESR license.

GEH gave reasonable justification for areas not currently characterized at the time of LTP submittal and, in response to Technical RAI 1 (ML24085A792), GEH included an update detailing completion of additional characterization activities. The licensee stated that the VBWR LTP will be updated to include additional information on radiological conditions and the inventory of residual radioactivity for transfer to the EVESR license based on this characterization. The NRC staff finds it acceptable not to include a complete description of radiological conditions at VBWR because this information will be evaluated in the EVESR LTP submittal. The NRC staff reviewed the information in figures, tables, and text in Chapter 2 of the LTP as well as the evaluations documented in Enclosure 3 and found that there were reasonable efforts made to characterize and evaluate the residual contamination levels in accessible portions of the facility for the purpose of quantifying total activity for transfer to the EVESR license. Therefore, the VBWR LTP meets the areas of review as described in NUREG-1700, Section 2.2. Based on this review, the NRC staff determined that the licensee has provided an adequate site characterization given the scope of the approval of the VBWR LTP as required by 10 CFR 50.82(a)(9)(ii)(A).

3.3 Remaining D&D Activities Chapter 3, Remaining D&D Activities, supplemented by Chapter 4.0 Site Remediation Plan, describes the remaining D&D activities at the VBWR site following the guidance of NUREG-1700 and RG 1.179. The licensee states that activities will be undertaken pursuant to the current 10 CFR Part 50 license for VBWR, congruent with the VNC VBWR/EVESR LPSDAR, Change Authorization Program, Radiation Protection Program, QA Program, written work plans, and the requirements of 10 CFR 50.82(a)(6).

As discussed in Section 3.0 of the LTP, VNCs primary goals are to decommission VBWR safely and terminate the VBWR license. The final state of the VBWR will be subject to future final release plans under the EVESR license as part of the overall VBWR/EVESR reactor facility area.

6 3.3.1 Completed and Future Decommissioning Activities VBWR LTP Section 3.2 includes a discussion of all completed decommissioning activities and tasks at the time of LTP submittal, including a description of: the offsite transfer of spent nuclear fuel; liability reduction activities in 2007 that consisted of dismantlement and disposal of most remaining major components under the VBWR license; asbestos and lead abatement along with disposal of removeable bioshield in 2022; reactor vessel water removal in 2022; and, reactor vessel pipe removal and closure of openings in 2023.

VBWR LTP 3.3, as originally submitted, discussed the sequence of remaining activities to be completed to support license termination at the time of LTP submittal, including the removal of the reactor vessel and its internals with its packaging and transport for disposal at a commercial site. The licensee described the plan for these activities to involve cutting an opening in the containment building and lifting the whole reactor vessel vertically out with an external crane, then transporting the vessel to a licensed disposal facility. Concurrently, packaging decommissioning generated material for transport and disposal as radioactive waste was to occur along with complete radiation surveys for remediated areas and updates to estimates of residual radioactivity remaining as needed for supporting the transfer of VBWR residual radioactivity to the EVESR license and supporting the requested exemption from 50.82(a)(11)(ii). LTP Table 3-1 contains a projected schedule for major remaining activities.

NRC staff notes that, during the review of this amendment request, all activities leading up to and including the reactor vessel removal have been completed pursuant to 10 CFR 50.59 as described in NRC inspection report 050-00018/2023-002 dated January 9, 2024 (ML23362A083).

In response to Technical RAI 5 (ML24085A792), GEH amended Section 3.3 and clarified that very little, if any remediation would occur prior to complete transfer of residual radioactivity to the EVESR license.

3.3.2 Estimate of Quantity of Radioactive Material to be Shipped for Disposal VBWR LTP Section 3.4 Estimate of Quantity of Radioactive Material to be Shipped for Disposal states that waste consists broadly of the VBWR Reactor Vessel with internals and miscellaneous waste generated during decommissioning activities, specifically concrete from the bioshield and piping associated with the reactor vessel. LTP Table 3-2 contains information on estimated solid waste activity and volume. The total estimated volume is 9,240 ft3.

No liquid waste is anticipated to be generated during the performance of the remaining activities other than minor quantities as may be needed to support dismantling and activities will be performed in a manner that reduces/eliminates generation of airborne radioactive materials.

The LTP states radioactive material will be disposed of as radioactive waste in accordance with 10 CFR 20.2001. VNC has access to radioactive waste disposal facilities in Utah and Texas for the disposal of radioactive waste for this license termination.

On August 7, 2024, the licensee submitted Update to the License Termination Plan for Vallecitos Boiling Water Reactor - Environmental Report (ML24220A200) and clarified that demobilization has been completed. The licensee defines demobilization as including remediation of the sump, decontaminating and removing, if feasible, all project equipment and materials brought on site, disposal of project-generated waste such as concrete from expansion

7 joint areas, reactor pit, etc., and returning the work area to a clean, safe condition. As such, no further waste disposal is anticipated as part of the license termination of the VBWR.

3.3.3 Proposed Control Mechanisms The VBWR LTP describes proposed methods to implement during decommissioning and decontamination activities to control radioactive release and re-contamination of remediated areas. Section 3.4.2, Liquid Radioactive Waste, of the LTP states that no liquid waste is anticipated to be generated during the performance of the remaining activities other than minor quantities as may be needed to support dismantling activities. These waste waters will either be stabilized (e.g., solidified) and disposed of as radioactive waste or processed on-site at the waste evaporator plan with remaining residue stabilized and disposed of as radioactive waste.

VBWR LTP Section 3.4.3, Airborne Radioactive Waste, states that airborne radioactive materials will be reduced/eliminated by the following processes:

Enclosures will be used during major cutting and demolition activities to prevent spread of airborne radioactive materials.

Portable ventilation systems with HEPA filters will be used for minimizing work area airborne contamination and limiting releases to the environment.

Fixatives and/or protective covering will be used for preventing generation of airborne activity during movement of highly contaminated components. Dry surfaces will be wetted to minimize resuspension during demolition activities.

The LTP describes additional decontamination controls that will be implemented according to the remediation method being used. For example, with scabbling and needle guns, exhaust air passes through HEPA filtration devices. For mechanical/thermal cutting techniques, water applied to cool and lubricate the cable also aids in control of airborne dust. For diamond wire cutting, a slurry collection system can be installed to collect contaminated cutting slurry, decant the slurry and recycle the water.

3.3.4 Occupational Exposure Estimates The VBWR LTP contains a list of VBWR facilities, planned decommissioning and decontamination activities and estimated worker exposure (person-rem) presented in LTP Table 4-1, ALARA Dose Estimate for Reactor Vessel Removal. The only major dismantling/decommissioning activity is the reactor vessel removal and packaging, which has already been completed at the time of this review pursuant to 10 CFR 50.59. LTP Table 4-1 estimates the total occupational exposure for reactor vessel removal to be 5.75 person-rem.

There are no other major work activities that are anticipated to represent potentially significant radiological work. However, all work processes will be conducted under the Radiation Protection (RP) Program, including pre-job dose estimates and establishing RP controls.

3.3.5 NRC Evaluation of Remaining D&D Activities The NRC staff reviewed the information in the VBWR LTP for the identification of remaining site dismantlement activities, as described in NUREG-1700 Section 2.3, Identification of Remaining Site Dismantlement Activities.

8 The VBWR LTP summarizes the remaining site dismantlement activities and associated occupational dose. NRC staff notes that the only remaining site dismantlement activity discussed, reactor vessel removal and packaging, has already been completed at the time of this review pursuant to 10 CFR 50.59. However, the licensee commits to conducting all work processes under the VNC RP program which includes a pre-job dose estimate and establishes HP controls. The LTP also provides additional information related to the remaining D&D tasks.

This information included an estimate of the quantity and types of radioactive material to be released in accordance with the licensed material disposal requirement of 10 CFR 20.2001(a)(1), a description of proposed control mechanisms to ensure areas are not re-contaminated, and a characterization of radiological conditions to be encountered.

Because there are no further VBWR decommissioning activities after reactor vessel removal and packaging, the licensee does not need to provide sufficient data for use in planning further decommissioning activities such as projected schedules, waste volume costs, dose assessments, and health and safety considerations; or lists of the remaining activities that do not require any additional licensing action as described in NUREG-1700, Section 2.3.

Therefore, the VBWR LTP meets the areas of review described in NUREG-1700, Section 2.3.

Based on this review, the NRC staff determined that the licensee has identified, in sufficient detail, the remaining dismantlement activities necessary to complete decommissioning of the facility, as required by 10 CFR 50.82(a)(9)(ii)(B).

3.4 Site Remediation Plan 3.4.1 Site Remediation Objectives Chapter 4 of the VBWR LTP, along with updates in response to Technical RAI 5, discuss the VBWR site remediation plan. As stated in Section 4.1, Decommissioning Objectives, the primary objective is to remove the reactor vessel which contains the majority of the remaining radioactive material. Based on current known radiological conditions of the external ventilation system, spent fuel pool and the external sump, no remediation will be performed on these items.

Soil remediation is not within the scope of the VBWR LTP as land areas outside of the VBWR reactor building will come under the authority of the EVESR license. The licensee states that residual radioactive materials will be controlled to prevent spread and contamination of the environment.

In response to Technical RAI 5 (ML24085A792), the licensee clarified that very little, if any, VBWR remediation will be performed prior to transfer of the remaining residual radioactivity to the EVESR license.

3.4.2 Site Remediation Activities VBWR LTP Section 4.2 Decommissioning Activities discusses appropriate remediation techniques, equipment, and material that will be used, as needed, to support remediation activities. These include scabbling methods, sponge and abrasive blasting, and mechanical and/or thermal techniques which may be used to cut metal structures. Additional remediation techniques that may be used for structural surfaces may include general washing, wiping, pressure washing, and vacuuming.

The licensee states that remediation will be performed only if determined to be As Low as Reasonably Achievable (ALARA) for worker protection and that all work will be performed

9 under the VNC Work Control Process, which incorporates the VNC QA Program, Radiation Protection Program and Health and Safety Program. Selection of decommissioning methods is heavily influenced by worker and public ALARA considerations. According to LTP Section 4.4, Remediation Actions, remediation actions are performed throughout the decommissioning process. The remediation action taken is dependent on the material contaminated and extent of contamination. The principal materials that may be subjected to remediation are hardened structural surfaces and residual dry activated waste and sludges. In response to Technical RAI 5 (ML24085A792), GEH updated LTP Section 4.4 to reflect that very little, if any, remediation will occur prior to transfer of residual radioactivity to the EVESR license.

Section 4.5 Decommissioning Work Controls states that all radiological decommissioning work activities will be performed under the VNC RP Program, using current VNC work processes, RWPs, and ALARA reviews and approvals. The VNC RP Program supports all radiological operations at VNC; this program fully implements the radiation protection requirements of 10 CFR Part 20 and has undergone NRC inspections since its implementation. Throughout the various VNC operations, GEH decontaminated structures, systems, and components as a consequence of performing maintenance or repair actions. The techniques used during such operations are the same as, or similar to, the techniques used during decommissioning to reduce personnel exposure to radiation and contamination and to prevent the spread of contamination from contaminated areas.

The licensee also states that the performance of the dismantling and remediation activities will be evaluated, planned and controlled under the VNC Work Control Process. This process integrates a detailed examination of the hazards, risks and safety measures necessary for worker protection. The RP RWP process is an integral element of this work planning and control. ALARA evaluations are an integral part of the RWP process. ALARA goals will be established for major dismantling activities, such as the reactor vessel removal; pre-job briefs will be conducted; doses will be tracked using electronic personal (radiation) dosimeters (EPDs), appropriate radiation safety measures, such as personal protective equipment (PPE),

including respiratory protection, will be evaluated. RP job coverage is provided where needed for monitoring RP practices, controlling exposures, and minimizing dose.

As stated in the previous section of this document, the only major dismantling/decommissioning activity is the reactor vessel removal which has been completed as of the time of this review.

There are no other major work activities that are anticipated that involve significant radiological materials. However, all work processes will be conducted under the established RP Program, including pre-job dose estimates and determination of RP controls.

3.4.3 NRC Evaluation of Site Remediation Plan The NRC staff reviewed the information in the VBWR LTP in accordance with Section 2.4, Remediation Plans, of the NUREG-1700. As described therein, the purposes of the NRC staffs review are to ensure the LTP (1) addresses any changes in the radiological controls to be implemented to control radiological contamination associated with the remaining decommissioning and remediation activities; (2) discusses in detail how facility and site areas will be remediated to meet the proposed residual radioactivity levels for license termination; and (3) includes a schedule that demonstrates how and in what time frame the licensee will complete the interrelated decommissioning activities.

The NRC staff notes that, because termination of the VBWR license is contingent on the transferal of the remaining facility and its in-situ residual radioactivity to the authority of the

10 EVESR license, the VBWR license may be terminated without demonstrating that the facility has met the license termination criteria in 10 CFR 20, Subpart E. As such, a discussion of the license termination criteria is not applicable to this review. Similarly, the NRC staff notes that because residual radioactivity will be transferred to the EVESR license and the licensee will request an exemption from the 10 CFR 50.82(a)(11)(ii) requirement that the VBWR meet 10 CFR Part 20, Subpart E license termination criteria, an ALARA evaluation is not required. In response to Technical RAI 5, the licensee states that very little, if any, remediation will occur prior to transfer of residual radioactivity to the EVESR license. The VBWR LTP discussed in detail how the licensee intends to remediate the VBWR facility to residual radioactivity levels that allow for license termination by transfer to EVESR license, including a summary of the removal and remediation techniques and potential tasks planned for the site. The LTP also included a summary of the VNC radiation protection program and decommissioning work controls that will be employed during the remaining decommissioning activities. The licensee references existing procedures such as the Quality Assurance Program and Change Authorization Process and commits to conducting decommissioning activities in accordance with VBWR procedures and approved work packages. LTP Table 3-1, Major Remaining Activities and Completion Dates, provides a schedule that demonstrates how and in what time frame the licensee will complete the interrelated decommissioning activities. The licensee does not indicate plans for any onsite disposal of decommissioning waste.

Therefore, the VBWR LTP meets the applicable areas of review described in NUREG-1700, Section 2.4. Based on this review, the NRC staff finds the licensee has provided an adequate discussion of its radiological site remediation plans for the remaining decommissioning activities, as required by 10 CFR 50.82(a)(9)(ii)(C).

3.5 Final Status Survey 3.5.1 Final Status Survey Approach As described in the LTP, a request for an exemption from 10 CFR 50.82(a)(11)(ii) requiring the VBWR meet the requirements for release according to 10 CFR Part 20, Subpart E, is proposed to be submitted by GEH (ML24085A792). In support of that exemption request, the transmittal will also include a license amendment request to transfer the remaining VBWR facility and its in-situ residual radioactivity to the authority of the EVESR license. These actions are according to the decommissioning licensing strategy first outlined in the GEH Letter to the NRC, GEH Description of Process for Decommissioning the Vallecitos Nuclear Center Shutdown Reactors (ML21315A005), dated November 11, 2021, and later developed into the VNC LPSDAR. This series of actions will enable the VBWR license to be terminated and the final decommissioning of the VBWR facility to be accomplished coincident with the license termination of the EVESR, which is co-located with the VBWR at the VNC site. The decommissioning will be accomplished consistent with the EVESRs license termination date of April 15, 2030.

Because the EVESR and the VBWR are co-located on the 300 Area site, and because the remaining VBWR facility components are to be transferred to the EVESR license, a FSSP is to be addressed as part of the final decommissioning activities for EVESR. This plan, addressing the demonstration of meeting the license termination criteria for EVESR and release of the 300 Area, in accordance with the requirements of 10 CFR 50.82(a)(11)(ii), will then cover both the EVESR and VBWR facilities. This FSSP will be submitted as a component of the EVESR LTP prior to April 15, 2028.

11 3.5.2 NRC Final Status Survey Evaluation The NRC staff reviewed the LTP regarding the licensees FSSP. Because the plan in the LTP is for the VBWR facility to be transferred to the license for the co-located EVESR facility, the plan also includes a future request on behalf of the VBWR license to seek an exemption from the 10 CFR 50.82(a)(11)(ii) requirement for the licensee to include a final radiation survey to support termination of the license. Instead, an FSSP which includes the VBWR facility, will be submitted as part of the decommissioning activities for EVESR. Therefore, the NRC finds that the omission of more detailed information regarding the plans for the final radiation survey from the VBWR LTP is acceptable for this situation, since both facilities are co-located on the 300 Area site, and the survey associated with the VBWR facility will be addressed by the EVESR FSSP.

3.6 License Termination Radiological Criteria Compliance 3.6.1 License Termination Radiological Criteria Compliance Approach VBWR LTP Section 6.0 Compliance with Radiological Criteria for License Termination, as supplemented by the RAI response dated March 25, 2024 (ML24085A792), identifies that a request for an exemption from 10 CFR 50.82(a)(11)(ii), which requires the VBWR to meet the requirements of 10 CFR Part 20, Subpart E, for license termination, will be submitted by the licensee after the completion of the license transfer from GEH to NorthStar Vallecitos.

As discussed in the previous section, a FSSP is to be addressed as part of the decommissioning activities for the EVESR. This plan, to address the EVESR license termination and release of the 300 Area will demonstrate compliance with the requirements of 10 CFR 50.82(a)(11)(ii) for EVESR and the remaining, transferred VBWR facilities.

3.6.2 NRC License Termination Radiological Criteria Compliance Evaluation The NRC staff reviewed the VBWR LTP regarding the licensees radiological criteria for license termination. Based on a plan to request an exemption from 10 CFR 50.82(a)(11)(ii) for the VBWR and a commitment to submit a FSSP as part of the decommissioning activities for EVESR that will meet the requirements of 10 CFR 50.82(a)(11)(ii), the NRC finds this explanation acceptable, as both facilities are co-located on the 300 Area site.

4.0 FINANCIAL EVALUATION 4.1 Updated Site-Specific Remaining Decommissioning Cost Estimate Evaluation As required by 10 CFR 50.82(a)(9), GEH estimated the remaining decommissioning costs associated with the termination of the VBWR license, which was an updated figure from the estimated costs provided in GEH Vallecitos Nuclear Center LPSDAR, Revision 121. The estimate update incorporates the site specific and special tasks that have been prescribed or implemented as a result of the ongoing decommissioning planning. The basis of the estimate and the sources of information, methodology, site-specific considerations, assumptions, and total costs were presented in the revision to the LPSDAR.

1 ADAMS Accession No. ML22264A327

12 Prior to starting the detailed review of the cost estimate, the NRC staff reviewed the estimate to confirm the supporting systems/structures necessary to support the safe operation had been identified in the estimate. The validity of the cost estimate is based on a reasonable estimate of the cost to decommission the remaining supporting systems and structures as well as confirming that all of the major equipment necessary to support operation was included.

In Revision 12 to the LPSDAR, the licensee has divided the estimated remaining decommissioning costs into the following Cost Categories: Planning and Preparation; Decontamination and Dismantlement; Release Survey; Waste Packing and Shipping; Waste Disposal; Equipment/Supplies; Laboratory Costs; Utilities/Shared Services; and NRC Inspection. Staff noted that the Decontamination and Dismantlement and the Release Survey values are $0 in the cost estimate due to the GEH strategy of transferring these liabilities from the VBWR license to the EVESR license (both co-located at the VNC). Additionally, this estimate includes a contingency of 25 percent across the major activities. The staff reviewed the contingency factor and the cost categories used in the GEH cost estimate and found the cost estimate to be reasonable.

4.2 Decommissioning Funding Plan Evaluation In addition to the requirement to provide an updated site-specific estimate of remaining decommissioning costs for the evaluation of the LTP, GEH is also required to provide annual decommissioning funding status reports for the VBWR. Pursuant to 10 CFR 50.82(a)(8)(v), the licensee is required to provide specific information related to decommissioning costs, expenditures, and funds. Accordingly, on March 28, 2023, GEH submitted the security bond riders for all VNC licenses, including the VBWR2. The surety bond amount correlates to the remaining radiological decommissioning cost estimate for the VBWR. According to 10 CFR 50.75(e)(1)(iii)(A), a licensee may rely on surety methods, including surety bonds, to provide financial assurance for decommissioning. Therefore, the staff determined that both the decommissioning funding assurance amount and methodology are reasonable and in compliance with NRC regulations.

4.3 Conclusion The NRC staff finds the site-specific cost estimate for remaining radiological decommissioning cost for the VBWR is reasonable, and that the amount covered by the surety bond designated for the VBWR will be sufficient to fund the remaining radiological decommissioning expenses.

5.0 ENVIRONMENTAL EVALUATION In accordance with 10 CFR 50.82(a)(9)(ii)(G), requiring a supplement to the environmental report (ER) describing any new information or significant environmental change associated with the licensee's proposed termination activities, GEH submitted an ER as Enclosure 1 to the LTP submittal of September 15, 2023 (ML23261A591) that was supplemented by letter dated August 7, 2024 (ML24220A200). Pursuant to 10 CFR 51.21 (stating criteria for, and identification of, licensing and regulatory actions requiring environmental assessments), 10 CFR 51.32 (addressing a finding of no significant impact), and 10 CFR 51.35 (providing the requirement to publish a finding of no significant impact, and limiting Commission actions pre-publication of the finding of no significant impact), a notice of the issuance of the NRCs environmental assessment and finding of no significant impact were published in the Federal Register on 2 ADAMS Accession No. ML23104A417

13 October 16, 2024 (89 FR 83521). Accordingly, based upon the environmental assessment, the Commission has determined that issuance of this amendment will not have a significant effect on the quality of the human environment.

6.0 PARTIAL SITE RELEASE CONSIDERATIONS By letter dated April 24, 2015 (ML15114A437 and ML15114A438), GEH requested to release, for unrestricted use, the unused northern section (approximately 610 acres) of the approximately 1,600 acres of the VNC site. By letter dated December 14, 2018 (ML18348A425), as supplemented by letter dated February 28, 2019 (ML19057A466), GEH requested to release, for unrestricted use, approximately seven acres of the VNC property within a construction easement along Vallecitos Road (California State Route 84) to be made available to Alameda County Transportation Commission to support road development and widening.

Both of these areas were determined to be non-impacted by the licensee based on four sources of information: visual inspection; historical records review; process knowledge; and the results of sentinel measurements. The licensee conducted environmental assessments of these areas prior to requesting the release. The results of the assessments were that no adverse or recognized environmental conditions were identified on the sites other than the recognized environmental condition of the VNC operational area being within one-half mile of the sites to be released. No historical recognized environmental conditions were found on the sites based on the review of aerial photographs, site records and interviews with site personnel. The NRC verified this information for the 610-acre parcel during a site visit between July 20-23, 2015 (ML15303A361) by conducting a confirmatory radiological survey of the area. Likewise, the NRC staff verified the information for the seven-acre area during a site visit between February 5-6, 2019 (ML19239A118), by conducting a confirmatory radiological survey of the area. For both areas the results of gamma radiation surveys combined with laboratory analytical results from soil samples supported the conclusion that the areas were not radiologically impacted by licensed site activities. The 610-area was released from the VBWR and EVESR licenses by letter dated May 3, 2016 (ML16007A348). The seven-acre area was released from the VBWR and EVESR licenses by letter dated September 30, 2019 (ML19249C554).

7.0 ENVIRONMENTAL PROTECTION AGENCY MEMORANDUM OF UNDERSTANDING The Memorandum of Understanding on Consultation and Finality on Decommissioning and Decontamination of Contaminated Sites dated October 9, 2002 (ML022830208) between NRC and U.S. Environmental Protection Agency contains criteria related to the DCGL soil concentrations proposed by licensees if those proposed concentrations in an LTP exceeds any of three trigger criteria contained in the Memorandum of Understanding. Since this LTP does not propose any DCGL soil concentrations, NRC did not engage with Environmental Protection Agency on the Memorandum of Understanding.

8.0 STATE CONSULTATION

In accordance with the Commissions regulations in 10 CFR 50.91(b)(4), the California State official, Justin Cochran, Senior Nuclear Advisor - California Energy Commission, was notified of the proposed issuance of the amendment on November 4, 2024 (ML24326A168). The State official responded by e-mail dated November 22, 2024 (ML24330A032) and did not have any comments or objections to issuing the amendment.

14

9.0 CONCLUSION

S The NRC has concluded, based on the considerations discussed above, that there is reasonable assurance that the remainder of the decommissioning activities at the VBWR, as described in the LTP will: (1) be performed in accordance with the regulations in 10 CFR Part 50; (2) will not be inimical to the common defense and security or to the health and safety of the public; and (3) will not have a significant effect on the quality of the environment.