ML24283A137

ENC1 Redacted Evinci Final SE PDC TR

ML24283A137
Person / Time
Site:	99902079
Issue date:	10/16/2024
From:	John Segala NRC/NRR/DANU/UAL2
To:	Schoedel A Westinghouse
References
EPID L-2023-TOP-0040, EVR-LIC-RL-001-P, EVR-LIC-RL-001-NP
Download: ML24283A137 (1)

Text

OFFICIAL USE ONLY PROPRIETARY INFORMATION OFFICIAL USE ONLY - PROPRIETARY INFORMATION WESTINGHOUSE ELECTRIC COMPANY - FINAL SAFETY EVALUATION OF TOPICAL REPORT EVR-LIC-RL-001-P/NP, WESTINGHOUSE PRINCIPAL DESIGN CRITERIA TOPICAL REPORT FOR THE EVINCITM MICROREACTOR (EPID NO. L-2023-TOP-0040)

SPONSOR AND SUBMITTAL INFORMATION Sponsor:

Westinghouse Electric Company LLC (Westinghouse)

Address:

1000 Westinghouse Drive Cranberry Township, PA 16066 Project No.:

99902079 Submittal Date:

June 28, 2023 Submittal:

Agencywide Documents Access and Management System (ADAMS)

Accession No. ML23179A196 Correspondence Dates and ADAMS Accession Nos:

U.S. Nuclear Regulatory Commission (NRC) Staff Completeness Determination dated August 15, 2023, (ML23226A274).

NRC staffs requests for additional information (RAIs), dated November 16, 2023, (ML23325A028).

Westinghouse RAI responses dated December 15, 2023, (ML23352A134).

Westinghouse Topical Report (TR) Revision 1 dated May 15, 2024, (ML24137A079).

1.0 BRIEF DESCRIPTION OF THE TOPICAL REPORT AND BACKGROUND By letter dated June 28, 2023 (Reference 1), Westinghouse Electric Company LLC (Westinghouse/ WEC) submitted the EVR-LIC-RL-001-P/NP, Principal Design Criteria Topical Report, Revision 0, for the NRC staffs review. The TR contains a brief overview of the WEC eVinciTM Microreactor design, a summary of how the principal design criteria (PDC) were developed, and the PDC selected for the eVinciTM Microreactor (referred to as the eVinciTM Microreactor PDC in the TR). Westinghouse requested the NRC staffs review and approval of the eVinciTM Microreactor PDC TR so it may be referenced in the future Design Certification Application (DCA) for the eVinciTM Microreactor. Documentation that the PDCs are satisfied will be provided by Westinghouse within the DCA or future license application(s), as appropriate, and is not part of the subject TR.

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OFFICIAL USE ONLY - PROPRIETARY INFORMATION By email dated August 15, 2023 (Reference 2), the NRC staff informed Westinghouse that the TR provided sufficient information for the NRC staff to conduct a detailed technical review. On September 15, 2023 (Reference 3), and October 31, 2023 (Reference 4), the NRC staff held clarification meetings to support the review and development of the safety evaluation. By email dated November 16, 2023 (Reference 5), the NRC staff issued RAIs to Westinghouse; Westinghouse responded to the NRC staffs RAIs by letter dated December 15, 2023 (Reference 6). By letter dated May 15, 2024 (Reference 7), Westinghouse submitted Revision 1 of the eVinciTM Microreactor PDC TR which included changes made as a result of the clarifications discussed in the October 31 meeting (Reference 4) and the RAI responses.

2.0 REGULATORY EVALUATION

The regulations under Title 10 Code of Federal Regulations (10 CFR) Part 50, Domestic Licensing of Production and Utilization Facilities, Appendix A, General Design Criteria for Nuclear Power Plants, provides general design criteria (GDCs) for water-cooled nuclear power plants similar to those historically licensed by the NRC. Under the provisions of 10 CFR Part 50 and Part 52, Licenses, Certifications, and Approvals for Nuclear Power Plants, applicants for a construction permit (CP), operating license (OL), design certification (DC), combined license (COL), standard design approval (SDA), or manufacturing license (ML) must submit PDCs for the proposed facility.

Specifically, the following Commission regulations pertain to the PDCs:

Regulation 10 CFR 50.34(a)(3)(i), which requires, in part, that applications for a CP include PDCs for the facility. An OL would reference a CP, which would include PDCs.

Regulation 10 CFR 52.47(a)(3)(i), which requires, in part, that applications for a DC include PDCs for the facility.

Regulation 10 CFR 52.79(a)(4)(i), which requires, in part, that applications for a COL include PDCs for the facility.

Regulation 10 CFR 52.137(a)(3)(i), which requires, in part, that applications for an SDA include PDCs for the facility.

Regulation 10 CFR 52.157(a), which requires, in part, that applications for an ML include PDCs for the reactor to be manufactured.

The regulations listed above state that 10 CFR Part 50, Appendix A, establishes the minimum requirements for the PDCs for water-cooled nuclear power plants similar in design and location to plants for which CPs have previously been issued by the Commission and provides guidance to applicants in establishing PDCs for other types of nuclear power units. Since the eVinciTM Microreactor is not a water-cooled nuclear power plant, PDCs are required but it is not necessary that they directly align with the minimum requirements in the GDCs in 10 CFR Part 50, Appendix A. Recognizing that the GDCs in 10 CFR Part 50, Appendix A may not be appropriate for non-light-water reactors (non-LWRs), the NRC issued Regulatory Guide (RG) 1.232, Guidance for Developing Principal Design Criteria for Non-Light-Water Reactors, (Reference 8), which serves as guidance to develop PDCs for non-LWR designs.

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OFFICIAL USE ONLY - PROPRIETARY INFORMATION RG 1.232, Appendix C, Modular High-Temperature Gas-Cooled Reactor Design Criteria, contains design criteria intended to serve as an example set of criteria that meets the intent of the requirements of the GDCs for high temperature gas-cooled reactor designs (MHTGRs). The eVinciTM Microreactor design is similar to the design considered in the development of RG 1.232, Appendix C, but differs significantly with respect to its primary heat removal phenomena, as it uses sodium-based heat pipes rather than pumped helium. Accordingly, the eVinci Microreactor PDC TR references RG 1.232, Appendix C, extensively, but also references Appendix A, Advanced Reactor Design Criteria, where appropriate and Appendix B, Sodium-Cooled Fast Reactor Design Criteria, for PDC related to the use of sodium material, including interactions of sodium with other materials.

To further support the development of a comprehensive set of PDCs applicable to the eVinciTM Microreactor, and to align with its intended future licensing approach, Westinghouse applied additional guidance, listed below, as described in Section 3.0, PDC Development of the TR.

NEI 18-04, Revision 1, Risk-Informed Performance-Based Technology-Inclusive Guidance for Non-Light Water Reactor Licensing Basis Development, (Reference 9).

RG 1.233, Revision 0, Guidance for a Technology-Inclusive, Risk-Informed, and Performance-Based Methodology to Inform the Licensing Basis and Content of Applications for Licenses, Certifications, and Approvals for Non-Light-Water Reactors, (Reference 10).

NEI 21-07, Revision 1, Technology-Inclusive Guidance for Non-Light Water Reactors:

Safety Analysis Report Content for Applicants Using the NEI 18-04 Methodology, (Reference11).

Draft Regulatory Guide (DG) DG-1404 (Subsequently approved as RG 1.253, Revision 0), Guidance for a Technology-Inclusive Content-of-Application Methodology to Inform the Licensing Basis and Content of Applications for Licenses, Certifications, and Approvals for Non-Light-Water Reactors, (Reference 12).

SECY-18-0096, Functional Containment Performance Criteria for Non-Light-Water-Reactors, (Reference 13), and the associated staff requirements memoranda (SRM) SRM-SECY-18-0096 (Reference 14), detail the criteria that describe how advanced reactor designs such as the eVinciTM Microreactor, may justify the use of a functional containment consisting of multiple barriers to limit the release of radioactive materials, in lieu of a traditional LWR-style containment design.

The PDCs are integral to the review of the facility design and should be considered in the development of the facility and the structures, systems, and component (SSC) design bases.

PDCs aid in the NRC staffs evaluation of other regulations and allow the NRC staff to have reasonable assurance that the design will conform to the design bases with adequate margins for safety.

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3.0 TECHNICAL EVALUATION

3.1 Scope of Review TR Section 1.4, Request for NRC requests the approval of the set of PDCs proposed in TR Section 4, eVinciTM Microreactor Principal Design Criteria, including the list of GDCs determined to not be applicable to the eVinciTM Microreactor design in TR Table 4.1-1, Criterial Not Included as PDC for the eVinciTM Microreactor. Therefore, the NRC staffs review documented in this SE, focuses on the PDCs developed by Westinghouse and the GDCs that it determined to not be applicable.

The NRC staff notes that the information provided in TR Sections 2 and 3 is informational in nature and is used to inform the review of the PDCs proposed in the TR. The NRC staff makes no determination in this safety evaluation regarding the acceptability of the specific design described or the process used to develop the PDCs.

3.2 eVinciTM Microreactor Design Features As discussed in TR Section 2, Summary of the eVinciTM Microreactor Design and Facility Description, the proposed conceptual design for the eVinciTM Microreactor is a high-temperature, heat pipe-cooled, thermal spectrum, 15 MWth reactor. The reactor core is fueled with high-assay, low-enriched uranium (HALEU) tri-structural isotropic (TRISO) fuel and consists of horizontal hexagonal graphite blocks with channels for fuel, burnable absorbers, alkali metal heat pipes, and shutdown rods. The core is surrounded by a radial reflector that houses the control drums designed to manipulate core reactivity and allow the otherwise subcritical core to achieve criticality when the drums are specifically oriented. The control drums and shutdown rods provide independent, diverse means of achieving sub-criticality (shutdown).

The reactor core and reflector are contained within a canister that makes up an element of the functional containment design, with the layers of the TRISO fuel particles representing the other physical barriers. The vessel is filled with helium gas to enhance decay heat removal, which can be accomplished through the core block, radial reflector, core containment system (vessel), and shielding. Reactor heat produced for power generation (15 MWth) will be removed through alkali metal heat pipes and a primary heat exchanger (PHX) and will be converted to electric power

(~5MWe) through an open-air Brayton cycle power conversion system (PCS).

The eVinciTM Microreactor concept is designed such that the reactor canister and core, and the support and power conversion systems, can be transported in shipping containers by truck, rail, or waterway to an approved reactor site that has been appropriately constructed and prepared.

Following installation at the site, criticality testing, and subsequent operation will commence and continue, under remote monitoring with limited on-site operations, maintenance, and security staff, until the core reaches end of life. Following a reactors operation, a replacement reactor can be shipped to and installed at the site in its place, while the spent reactor is allowed to cool until it is ultimately removed from the site for refurbishment, refueling, and/or decommissioning, as appropriate.

The NRC staff notes that the design information provided in the TR and summarized above is informational in nature and is used to inform the review of the PDCs proposed in the TR. The NRC staff makes no determination in this safety evaluation regarding the acceptability of the specific design described.

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OFFICIAL USE ONLY - PROPRIETARY INFORMATION 3.3 eVinciTM Microreactor PDCs TR Section 4.2, eVinci Microreactor PDC, provides numbered sub-sections containing each PDCs title, the PDC terminology, a statement regarding terminology changes and/or departures from RG 1.232 terminology, a basis, and sources, for each of the eVinciTM Microreactor PDCs.

The following sub-sections of this SE provide the NRC staffs assessment of the eVinciTM Microreactor PDCs. The design criteria listed in TR Table 4.1-1 are not included as eVinciTM Microreactor PDCs and, therefore, are not included in the following sub-sections. Its exclusion from the eVinciTM Microreactor PDC, supporting justifications, and associated staff assessments are discussed in SE Section 3.4.

The NRC staff notes that Westinghouse is requesting approval for a proposed set of PDCs based on a preliminary design for the eVinciTM Microreactor and that the NEI 18-04 process is intended for use in supporting licensing. Future eVinciTM Microreactor design changes and associated implementation of the NEI 18-04 process could necessitate a revision to the proposed PDCs. Therefore, the staff conditions the approvals in this SE on limitation/condition 1 in section 4.0, which requires future licensing applicants referencing the TR to confirm that the PDCs remain appropriate for the design to be licensed.

3.3.1 PDCs That Are Identical or Largely Similar to GDC or RG 1.232 Criteria Many of the eVinciTM Microreactor PDCs proposed in the TR are identical to or largely similar to the analogous 10 CFR Part 50 Appendix A GDC or the criteria contained in the appendices of RG 1.232. The staff evaluated each proposed PDC for its specific applicability to the eVinciTM Microreactor design and determined whether the underlying safety basis documented in RG 1.232 remains applicable for each. This section summarizes the groups of Microreactor PDCs that the staff found acceptable on similar bases, as described below.

The staff found eVinciTM Microreactor PDCs 10, 11, 14, 15, 23, 24, 25, 28, 29, and 60 acceptable on the basis that the proposed language is either identical to the GDC or RG 1.232 criteria, or contains changes or additions considered minor or inconsequential in nature such that the underlying application of the criteria to the eVinciTM Microreactor design is effectively identical. The NRC staff determined that the criteria listed are applicable to the eVinciTM Microreactor design and that the underlying safety basis documented in RG 1.232 remains applicable for each.

The eVinciTM Microreactor PDCs 1, 2, 3, 4, 5, 16, 20, and 22 contain proposed language that is largely similar to that in the GDC or RG 1.232, but with the terms important to safety and postulated accident replaced to reflect the NEI 18-04 and NEI 21-07 terminology of safety significant and licensing basis event, respectively. The staff finds these PDCs to be acceptable on the basis that the NRC endorsed the approach described in NEI 18-04 in RG 1.233 and NEI 21-07 in RG 1.253. Additionally, the NRC staff considers these terminologies effectively analogous to each other in the context of the RG 1.232 guidance and finds that the underlying safety intent of the design criteria listed is not meaningfully impacted as a result of these terminology changes. Additionally, the NRC staff finds that the criteria listed are applicable to the eVinciTM Microreactor design and that the underlying safety basis documented in RG 1.232 remains applicable for each.

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OFFICIAL USE ONLY - PROPRIETARY INFORMATION 3.3.2 PDCs Influenced by Considerations of Independence, Redundancy, Diversity, or Defense-in-Depth The eVinciTM Microreactor PDCs 6, 17, 26, 34, and 78 include language that modifies GDC or RG 1.232 criteria, specifically related to the topics of SSC independence, redundancy, diversity, or defense-in-depth. The NRC staff acknowledges that the changes are made to align with the methodologies described in NEI 18-04 and NEI 21-07, subsequently referred to as the licensing modernization project (LMP). Specifically, the NRC staff notes that the methodology in NEI 18-04, endorsed by the NRC in RG 1.233, addresses the considerations of independence, redundancy, diversity, and defense-in-depth for use in licensing advanced reactors such as the eVinciTM Microreactor. The NRC staff finds these eVinciTM Microreactor PDCs acceptable provided that the endorsed LMP methodology is used in the future to support licensing the eVinciTM Microreactor design. Additionally, the NRC staff finds that the listed PDCs are applicable to the eVinciTM Microreactor design and that the underlying safety bases documented in RG 1.232, remain applicable for each, with the exception that the considerations related to independence, redundancy, diversity, and defense-in-depth are to be addressed through the implementation of the LMP. However, the NRC staff notes that the listed PDCs only remain acceptable if the LMP is implemented during the licensing process. Therefore, because the details regarding the implementation of the LMP are not yet available, the NRC staff imposes limitation/condition 2 regarding the acceptability of PDCs 6, 17, 26, 34, and 78.

Additional considerations related to PDCs 6 and 34 are further discussed in SE Section 3.4.1 and Section 3.4.3, respectively, as these PDCs encompass the requirements of, and replace, multiple RG 1.232 criteria. Furthermore, discussion regarding PDCs 17 and 78 are included in SE Section 3.3.6 and Section 3.3.12, respectively.

3.3.3 PDCs Pertaining to Microreactor Storage The eVinciTM Microreactor PDCs 61, 62, and 63 each include language that modifies RG 1.232 criteria wording regarding the handling and storage of reactor fuel. Specifically, the NRC staff acknowledge that the changes support a Microreactor deployment approach that involves handling and storage of fueled Microreactor units rather than individual fuel elements and will, therefore, not have a fuel handling system. The NRC staff notes that, while WEC intends to implement this deployment strategy and has developed these PDCs from that perspective, many technical and regulatory aspects involved in the implementation of this deployment approach are under consideration by the Commission at the time of this review, as detailed in SECY 24-0008 (Reference 15).

The NRC staff finds the proposed PDCs 61, 62, and 63 to be acceptable on the basis that they meet the intent of the criteria and support the rationale for the underlying safety bases documented in RG 1.232, in the context of the microreactor deployment approach planned, assuming that the storage of fueled microreactor units is ultimately determined to comply with NRC regulations and be acceptable in a future licensing action. Therefore, the NRC staff imposes limitation/condition 3 on the approval of eVinciTM Microreactor PDCs 61, 62, and 63.

Further, the NRC staff notes that the topics regarding the transportation of microreactor units with new fuel and/or spent fuel, and ultimate spent fuel disposal are outside the scope of this TR and SE. Therefore, the transportation and spent fuel topics will be evaluated under future licensing submittals.

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OFFICIAL USE ONLY - PROPRIETARY INFORMATION 3.3.8 Monitoring Radioactive Releases - PDC 64 PDC 64 is adapted from RG 1.232, Appendix A, Criterion 64. The adaptation addresses the fact that the eVinciTM Microreactor will leverage a functional containment design approach, as opposed to a traditional LWR-style containment structure. Additionally, the terminology changes align with the planned implementation of NEI 18-04, as previously discussed in SE Section 3.3.1. Revision 0 of the TR included terminology on which the NRC staff sought further clarification to ensure that the PDC would not be ambiguous or undefined. Specifically, phrases such as radiological significance, and barrier breach were proposed, but not well defined. In response to NRC staff questions raised during a closed meeting with WEC on October 31, 2023 (Reference 4), WEC revised the proposed PDC language. The language in TR Revision 1 better aligns with the RG 1.232 language and removes the potentially ambiguous terminology. The NRC staff finds that the intent of the criterion and the rationale for the underlying safety basis documented in RG 1.232 remains applicable. Therefore, the NRC staff finds eVinciTM Microreactor PDC 64 to be acceptable.

3.3.9 Cover Gas Purity Control - PDC 71 PDC 71 is adapted from RG 1.232, Appendix B, Criterion 71. The adaptations ensure the applicability to the eVinciTM Microreactor designs cover gas system and reflect that the design does not use sodium as a primary coolant. In a closed meeting on October 31, 2023, (Reference 4) the NRC staff and WEC discussed the structure and specific terminology of the PDC proposed in TR Revision 0. As a result of topics discussed in that meeting, WEC incorporated slight revisions in TR Revision 1. The NRC staff finds that the intent of the criterion and the rationale for the underlying safety basis documented in RG 1.232 remains applicable.

Therefore, the NRC staff finds eVinciTM Microreactor PDC 71 to be acceptable.

3.3.10 Sodium Leakage Detection and Reaction Prevention and Mitigation - PDC 73 PDC 73 adapts RG 1.232, Appendix B, Criterion 73, language to the eVinciTM Microreactor design, which uses sodium-based heat pipes in a thermal spectrum reactor. PDC 73 lists, by number, the requirements related to sodium and includes an additional numbered requirement to ensure passive heat removal system availability. The additional requirement stems from the fact that the source of sodium in the eVinciTM Microreactor design is contained in heat pipes, which are intended to provide core cooling. The NRC staff notes that the additional requirement is consistent with the general intent of the criteria, which is focused on the detection of potential sodium leakage and measures to address any potential adverse effects of sodium leakage.

Additionally, the proposed language eliminates any considerations of potential sodium-concrete reactions. The justification for this change was discussed between WEC and the NRC staff, and was further clarified by WEC in Revision 1 to the TR. Specifically, the NRC staff finds the change acceptable on the basis that the eVinciTM Microreactor design provides multiple barriers between the small quantity of sodium contained in the heat pipes and any other concrete SSCs, such that sodium-concrete interaction would be precluded by the conformance with the PDCs other requirements for the detection of sodium leakage and/or mitigation of the effects of potential leakage. Therefore, the NRC staff finds eVinciTM Microreactor PDC 73 to be acceptable on the basis that the intent of the criterion and the rationale for the underlying safety basis documented in RG 1.232, remains applicable.

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OFFICIAL USE ONLY - PROPRIETARY INFORMATION 3.3.11 Sodium/Water Reaction Prevention/Mitigation - PDC 74 PDC 74 terminology is largely consistent with that of RG 1.232, Appendix B, Criterion 74, with language pertaining to steam-water energy conversion systems removed because the eVinciTM Microreactor will use sodium heat pipes and an open-air Brayton cycle conversion system. The NRC staff determined that the intent of the criterion and the rationale for the underlying safety basis documented in RG 1.232, remains applicable to the eVinciTM Microreactor design.

Therefore, the NRC staff finds eVinciTM Microreactor PDC 74 to be acceptable.

3.3.12 Sodium Heat Pipe Interfaces - PDC 78 PDC 78 is developed from RG 1.232, Appendix B, Criterion 78, with changes to reflect that the eVinciTM Microreactor design contains sodium only in the heat pipes, and not in a primary coolant loop. Additionally, language regarding redundant barriers associated with sodium is removed. See the previous discussion in SE Section 3.3.2 regarding SSC independence, redundancy, diversity, and defense-in-depth and the associated limitation / condition regarding PDC 78. The NRC staff finds that the intent of the criterion and the rationale for the underlying safety basis documented in RG 1.232, remains applicable to the eVinciTM Microreactor design.

Therefore, the NRC staff finds eVinciTM Microreactor PDC 78, to be acceptable.

3.4 Criteria Not Included as PDCs for the eVinciTM Microreactor Table 4.1-1 of the TR lists the design criteria determined to not be applicable to the eVinciTM Microreactor and provides justification for its exclusion from the set of eVinciTM Microreactor PDCs. The NRC staff considered these criteria and whether exclusion was appropriate for each.

3.4.1 Monitoring, Inspection, and Testing - Criteria 18, 21, 32, 36, 37, 39, 40, 45, and 46 Westinghouse proposed in the TR that the PDCs associated with RG 1.232 criteria 18, 21, 32, 36, 37, 39, 40, 45, and 46, were not necessary because they are all related to monitoring, inspection, and testing of various SSCs and PDC 6 broadly encompasses these criteria. The NRC staff notes that the listed criteria contain significant portions of overlapping language that is effectively mirrored in PDC 6, with the applicability extended to a broad range of SSCs. Some of the listed RG 1.232 criteria include concepts of independence, redundancy, diversity, or defense-in-depth, or include terminology that does not directly align with the implementation of the NEI 18-04 methodology. In evaluating the replacement of these criteria with PDC 6, the NRC staff applied considerations analogous to those previously discussed in SE Section 3.3.1 and Section 3.3.2.

The NRC staff finds that PDC 6 is sufficient to encompass the intent of each of the listed criteria and that the rationale for the underlying safety bases in RG 1.232, remains applicable.

Additionally, the NRC staff finds that the PDC 6 language is broad enough to encompass the various SSCs that are specified in the replaced RG 1.232 criteria. Therefore, the NRC staff finds the exclusion of the listed criteria acceptable.

3.4.2 Reactivity Control - Criterion 27 Westinghouse determined that PDC 27 is not necessary because the objective of the PDC is satisfied by PDC 26. The omission of PDC 27, which is consistent with RG 1.232, is acceptable because eVinciTM Microreactor PDC 26 provides all four reactivity control provisions that are

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2. Email from the NRC to A. Schoedel, Westinghouse - Completeness Determination for the eVinci Microreactor Principal Design Criteria Topical Report dated August 15, 2023 (ML23226A275).

3. NRC, Westinghouse Electric Company - September 15, 2023, Meeting Summary of Closed Meeting regarding the Principal Design Criteria Topical Report dated October 11, 2023 (ML23271A068).

4. NRC, Summary of the October 31, 2023, Closed Meeting with Westinghouse Electric Company Regarding the Principal Design Criteria Topical Report for the eVinci MicroReactor Design dated December 18, 2023 (ML23331A266).

5. Email from the NRC to A. Schoedel, Westinghouse Electric Company: Transmittal of Request for Additional Information in support of NRC staff review of the Principal Design Criteria Topical Report for the eVinci Microreactor dated November 16, 2023 (ML23325A036).

6. Letter from A. Schoedel to the NRC, Submittal of Westinghouse response to the NRC Request for Additional Information on the Principal Design Criteria Topical Report for the eVinci Microreactor dated December 15, 2023 (ML23352A135)

7. Letter from A. Schoedel to the NRC, Submittal of the Westinghouse Principal Design Criteria Topical Report Revision 1 for the eVinciTM Microreactor (EVR-LIC-RL-001-P/NP) dated May 15, 2024 (ML24137A080).

8. NRC, Regulatory Guide, RG 1.232, Guidance for Developing Principal Design Criteria for Advanced (Non-Light Water) Reactors, dated April 30, 2018 (ML17325A611).

9. Nuclear Energy Institute, NEI 18-04, Revision 1, Risk-Informed Performance-Based Technology Inclusive Guidance for Non-Light Water Reactor Licensing Basis Development, dated August29,2019 (ML19241A472).

10. NRC, Regulatory Guide, RG 1.233, Guidance for a Technology-Inclusive, Risk-Informed, and Performance-Based Methodology to Inform the Licensing Basis and Content of Applications for Licenses, Certifications, and Approvals for Non-Light Water Reactors, dated June 30, 2020 (ML20091L698).

11. Nuclear Energy Institute, NEI 21-07, Revision 1, Technology Inclusive Guidance for Non-Light Water Reactor Safety Analysis Report: Content for Applicants Using the NEI 18-04 Methodology, dated March 1, 2022 (ML22060A190).

12. NRC, Regulatory Guide, RG 1.253, Revision 0, Guidance for a Technology-Inclusive Content-of-Application Methodology to Inform the Licensing Basis and Content of Applications for Licenses, Certifications, and Approvals for Non-Light-Water Reactors, dated March 22, 2024 (ML23269A222).

13. NRC, SECY-18-0096, Functional Containment Performance Criteria for Non-Light-Water-Reactors, dated September 28, 2018 (ML18114A546).

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14. NRC, SRM-SECY-18-0096, Staff Requirements - SECY-18-0096 - Functional Containment Performance Criteria for Non-Light-Water-Reactors, dated December 4, 2018 (ML18338A502).

15. NRC, SECY-24-0008, Micro-Reactor Licensing and Deployment Considerations: Fuel Loading and Operational Testing at a Factory, dated January 24, 2024 (ML23207A250).

Principal Contributor: D. Beacon, NRR Date: July 26, 2024