ML24074A371
| ML24074A371 | |
| Person / Time | |
|---|---|
| Site: | Hermes File:Kairos Power icon.png |
| Issue date: | 03/14/2024 |
| From: | NRC |
| To: | NRC/NRR/DANU |
| References | |
| Download: ML24074A371 (48) | |
Text
From:
Cayetano Santos Sent:
Thursday, March 14, 2024 12:48 PM To:
Weidong Wang; Larry Burkhart Cc:
Michael Orenak; Matthew Hiser; Brian Bettes; William Jessup; Stephanie Devlin-Gill (She/Her)
Subject:
Preliminary Chapters of Hermes 2 SE Attachments:
Chapter 10 - Experimental Facilities and Utilization.pdf; Chapter 11 -
Radiation Protection and Waste Management.pdf; Chapter 12 - Conduct of Operations.pdf; Chapter 14 - Technical Specifications.pdf; Chapter 16 - Other License Considerations.pdf; Chapter 17 - Decommissioning and Possession-only License Amendments.pdf; Chapter 18 - Highly Enriched to Low-enriched Uranium Conversion.pdf; Chapter 06 - Engineered Safety Features.pdf; Chapter 08 - Electrical Power Systems.pdf
- Weidong, Attached are several preliminary chapters from the safety evaluation (SE) for the Hermes 2 construction permit application. These chapters have been reviewed by branch chiefs and received a preliminary review by OGC. However, these chapters are not final because they still need to be reviewed by division management and receive the final OGC review. Thus, these preliminary chapters could change between now and the approved SE that will be sent to ACRS for formal review. I am sending these chapters in advance so that members can become familiar with the safety evaluation and begin preparing for the formal review.
I expect to send the remaining preliminary chapters to you piecemeal after they receive the preliminary OGC review by April 16, as the first planned subcommittee meeting is May 16.
However, if the more complex chapters (e.g., chapters 5 and 13) are delayed beyond April 16, I will let you know ASAP.
Kairos Power submitted Revision 0 of the preliminary safety analysis report (PSAR) for Hermes 2 in July 2023. All preliminary SE chapters being sent to the ACRS refer to Revision 1 of the PSAR. Although Revision 1 of the PSAR has not been submitted, Kairos stated their intent to do so once all PSAR changes are known (i.e., the end of the technical review). The current list of docketed PSAR changes that will be incorporated into Revision 1 of the PSAR can be found in ADAMS and on the NRC public webpage at https://www.nrc.gov/reactors/non-power/new-facility-licensing/hermes2-kairos/documents.html.
The staff has taken a different approach toward the Hermes 2 SE considering that Hermes 1 and Hermes 2 CP applications have most of the same information. Due to these similarities, the staff leveraged the Hermes 1 SE to the extent possible for Hermes 2, using an incorporation by reference for many sections. The following description, taken from the
forthcoming Chapter 1 of the Hermes 2 SE, discusses how the staffs review of Hermes 1 was applied to its review of the Hermes 2:
Use of Precedent Docketed Information and Safety Evaluation The staffs review of the Hermes 2 CP application was informed by the Hermes 1 CP application review. The Hermes 2 facility includes many SSCs that are identical to those that would be used in the Hermes 1 facility. Accordingly, large portions of the Hermes 1 PSAR are identical to the Hermes 2 PSAR. In the July 14, 2023, CP application submittal (ML23195A121), Kairos highlighted the differences between the Hermes 1 and Hermes 2 PSARs in two ways. First, Kairos used blue font in the Hermes 2 PSAR to identify any modified or new text. Second, Kairos provided a summary (ML23195A132) of the information deleted from the Hermes 1 PSAR to generate the Hermes 2 PSAR.
Based on the consistencies between the Hermes 1 and Hermes 2 PSARs, the staff is leveraging the Hermes 1 SE to the greatest extent possible to support its review of the Hermes 2 CP application. Accordingly, Kairos identified the Hermes 1 docketed information and audit information that is applicable to the Hermes 2 CP application in two letters dated October 27, 2023 (ML23300A141 and ML22300A144). This information is considered docketed information for the Hermes 2 CP application and was used to inform the staffs review.
Format of Hermes 2 Safety Evaluation Sections Applicable contents of the Hermes 1 SE were incorporated by reference into this SE to the extent possible. To determine which Hermes 1 SE content could be incorporated by reference, the staff reviewed the differences between the Hermes1 and Hermes 2 PSARs. Where the Hermes 2 PSAR only contained minor (e.g., minimal or no effect on the NRC safety evaluation) or editorial changes, as compared to the Hermes1 PSAR, the staffs SE was largely limited to incorporating by reference applicable portions of the Hermes 1 SE. Similarly, where the Hermes 2 PSAR contained a limited number of significant but discrete changes, but was otherwise identical to the Hermes 1 PSAR, the staffs SE was likewise limited to an evaluation of the variances between the two PSARs.
In this case, the balance of the staffs SE also incorporated by reference applicable portions of the Hermes 1 SE. Based on this approach, many of the Hermes 2 SE sections are organized using the following structure:
Brief introduction summarizing the Hermes 2 PSAR content with a focus on any changes in comparison to the Hermes 1 PSAR.
Regulatory evaluation section that, in most cases, incorporates by reference the regulations and guidance from the corresponding section of the Hermes 1 SE due to the similarity of the Hermes 1 and Hermes 2 facility designs.
Technical evaluation that:
Identifies the consistent and modified Hermes 2 PSAR information, as compared to the Hermes 1 PSAR.
Incorporates by reference, as appropriate, content from the Hermes 1 SE for PSAR information that is consistent between Hermes 1 and Hermes 2.
Evaluates the new design information and non-editorial changes (i.e., minor and/or few significant changes), as compared to the
Hermes 1 SE. The depth of the staff review provided for each change is dependent on the significance of that change.
A full conclusion specific to the Hermes 2 review that is consistent with the Hermes 1 SE conclusion for the corresponding section or chapter.
For Hermes 2 PSAR sections that contain entirely new information and/or several significant changes when compared to the Hermes 1 PSAR, a full evaluation without incorporations by reference was performed by the staff.
If you have any questions, please contact me or Mike Orenak.
-Tanny
Hearing Identifier:
Kairos_Hermes2_CPDocs_Public Email Number:
8 Mail Envelope Properties (MW4PR09MB901047CD19A3E62120856FBCE5292)
Subject:
Preliminary Chapters of Hermes 2 SE Sent Date:
3/14/2024 12:48:11 PM Received Date:
3/14/2024 12:48:00 PM From:
Cayetano Santos Created By:
Cayetano.Santos@nrc.gov Recipients:
"Michael Orenak" <Michael.Orenak@nrc.gov>
Tracking Status: None "Matthew Hiser" <Matthew.Hiser@nrc.gov>
Tracking Status: None "Brian Bettes" <Brian.Bettes@nrc.gov>
Tracking Status: None "William Jessup" <William.Jessup@nrc.gov>
Tracking Status: None "Stephanie Devlin-Gill (She/Her)" <Stephanie.Devlin-Gill@nrc.gov>
Tracking Status: None "Weidong Wang" <Weidong.Wang@nrc.gov>
Tracking Status: None "Larry Burkhart" <Lawrence.Burkhart@nrc.gov>
Tracking Status: None Post Office:
MW4PR09MB9010.namprd09.prod.outlook.com Files Size Date & Time MESSAGE 5669 3/14/2024 12:48:00 PM Chapter 10 - Experimental Facilities and Utilization.pdf 182916 Chapter 11 - Radiation Protection and Waste Management.pdf 288359 Chapter 12 - Conduct of Operations.pdf 262928 Chapter 14 - Technical Specifications.pdf 215981 Chapter 16 - Other License Considerations.pdf 153412 Chapter 17 - Decommissioning and Possession-only License Amendments.pdf 173924 Chapter 18 - Highly Enriched to Low-enriched Uranium Conversion.pdf 154415 Chapter 06 - Engineered Safety Features.pdf 832676 Chapter 08 - Electrical Power Systems.pdf 231463 Options Priority:
Normal Return Notification:
No Reply Requested:
No Sensitivity:
Normal Expiration Date:
10 EXPERIMENTAL FACILITIES AND UTILIZATION Research and test reactors may have many experimental uses. Many such reactors have special experimental facilities, which may penetrate the core or reflector, be located near the core, or be an integral part of the reactor. Using these facilities, samples can be irradiated in the core or reflector, or neutron or other radiation beams can be extracted from the core region through the biological shield. In addition to these traditional experimental purposes, some research and test reactors may be operated primarily to gather information and data that could be useful for the purposes of licensing future prototype facilities and power reactors. Such non-power reactors may not include specific experimental facilities, but the reactor itself and/or specific structures, systems, and components (SSCs) could be considered experimental facilities to demonstrate technology for eventual prototype and commercial scale up.
Kairos Power LLCs (Kaiross) Hermes 2 preliminary safety analysis report (PSAR), Revision X, Chapter 10, Experimental Facilities and Utilization, Section 10.1, Summary Description, states that Hermes 2 will not include special facilities dedicated to the conduct of reactor experiments or experimental programs. However, as discussed in Hermes 2 PSAR Chapter 1, The Facility, Section 1.1, Introduction, Kaiross purpose for Hermes 2 is to test and demonstrate the key technologies, design features, and safety functions of Kaiross fluoride salt-cooled, high temperature reactor (KPFHR) technology and its associated SSCs for a two-unit facility including electrical power production. As part of its construction permit review, the U.S.
Nuclear Regulatory Commission (NRC) staff (the staff) evaluated information on Hermes 2 SSCs in the PSAR, paying special attention to design and operating characteristics, unusual or novel SSCs being demonstrated by Hermes 2, and principal safety considerations. The preliminary design of unusual or novel SSCs, including special safety features for these SSCs and any added instrumentation or other features to monitor the performance of these SSCs, was evaluated to ensure the sufficiency of principal design criteria; design bases; information relative to materials of construction, general arrangement, and approximate dimensions; and high-level functional descriptions, to provide reasonable assurance that the final design will conform to the design bases. The information provided by Kairos in the Hermes 2 PSAR was also evaluated to determine whether it was adequate to provide reasonable assurance that a Title 10, Code of Federal Regulations (10 CFR) Part 50 construction permit (CP) for the Hermes 2 facility could be issued in accordance with applicable regulatory requirements and guidance on the basis that the facility could be constructed without undue risk to the health and safety of the public. The staff evaluations of unusual or novel Hermes 2 SSCs are found in other chapters of this safety evaluation (SE), particularly Chapter 3, Design of Structures, Systems, and Components, Chapter 4, Reactor Description, Chapter 5, Heat Transport System, Chapter 6, Engineered Safety Features, and Chapter 9, Auxiliary Systems.
In addition, the staff reviewed Kaiross Quality Assurance Program Description (QAPD) for ensuring the quality and performance of Hermes 2 SSCs during the design, construction, and operation of the facility. The staff documented its review of Kaiross QAPD in Chapter 12, Conduct of Operations, Section 12.9, Quality Assurance, of this SE.
The staff also reviewed Kaiross identification and justification for the selection of those variables, conditions, or other items which are determined to be probable subjects of technical specifications (TSs) for the facility, with special attention given to those items which may THIS NRC STAFF DRAFT SE HAS BEEN PREPARED AND IS BEING RELEASED TO SUPPORT INTERACTIONS WITH THE ACRS. THIS DRAFT SE HAS NOT BEEN SUBJECT TO FULL NRC MANAGEMENT AND LEGAL REVIEWS AND APPROVALS, AND ITS CONTENTS SHOULD NOT BE INTERPRETED AS OFFICIAL AGENCY POSITIONS.
significantly influence the final design. The staff documented its review of Kaiross probable subjects of TSs for the facility in Chapter 14, Technical Specifications, of this SE.
Hermes 2 PSAR Sections 4.3.1.1.1, 4.3.3, and 10.1 describe a material surveillance system (MSS), which is supported by the reactor vessel top head and provides a means to insert and remove material specimens (e.g., coupons) to support testing and assessment of material performance. During the General Audit (ML23115A480) for the Hermes 1 CP application review, Kairos confirmed that, consistent with Hermes 1 PSAR Section 10.1, the Hermes 1 MSS is not an experimental facility because the purpose of the MSS is to monitor and evaluate the performance of SSCs over the Hermes 1 operating life and Kairos does not plan to use the MSS to evaluate or irradiate other novel or experimental materials, i.e., which are not representative of Hermes 1 SSCs. Kairos also confirmed that any use of the MSS would not affect analyses of Hermes 1 operation or accidents in Hermes 1 PSAR Chapters 4 and 13. By letter dated October 27, 2023 (ML23300A144), Kairos confirmed that this information from the Hermes 1 general audit is also applicable to Hermes 2.
The staff evaluated the information on the Hermes 2 facility in the Hermes 2 PSAR and found that the preliminary design of the facility does not include any facilities penetrating or located near the reactor that are specifically designated as experimental facilities. The staff notes that the Hermes 2 facility includes unusual and novel SSCs that are an integral part of the facility, including tristructural isotropic particle (TRISO) fuel, Flibe salt coolant, with others, and that the facility includes features to monitor the performance of these SSCs to demonstrate the key technologies, design features, and safety functions of Kaiross KPFHR technology. However, these SSCs and features, as well as the QAPD and probable subjects of TSs that will help ensure the quality, performance, and safe operation of SSCs, are evaluated in other chapters of this SE, as discussed above. Therefore, the staff concludes that a separate evaluation using the guidelines of NUREG1537, Guidelines for Preparing and Reviewing Applications for the Licensing of Non-Power Reactors, Part 2, Standard Review Plan and Acceptance Criteria, Chapter 10, Experimental Facilities and Utilization, is not required. The staff will confirm that the final design conforms to the design basis, including that Hermes 2 will not include special facilities dedicated to the conduct of reactor experiments or experimental programs, during its review of a Hermes 2 operating license application.
10.1 References Kairos Power LLC. Submittal of the Preliminary Safety Analysis Report for the Kairos Power Fluoride Salt-Cooled, High Temperature Non-Power Reactor (Hermes), Revision 3, May 31, 2023, Pkg. ML23151A743.
. Letter dated October 27, 2023, Kairos Power Response to Hermes 2 General Audit Question 1.5-2, ML22300A144 Nuclear Regulatory Commission (U.S.) (NRC). NUREG1537, Guidelines for Preparing and Reviewing Applications for the Licensing of Non-Power Reactors, Part 1, Format and Content, and Part 2, Standard Review Plan and Acceptance Criteria. NRC: Washington, D.C. February 1996. ADAMS Accession Nos. ML042430055 and ML042430048.
. Summary Report for the Regulatory Audit of Kairos Power LLC Hermes Construction Permit Preliminary Safety Analysis Report - General Audit, June 2023, ML23160A287.
11 RADIATION PROTECTION AND WASTE MANAGEMENT The purposes of radiation protection and waste management programs and provisions are to ensure safety of a reactor facility and to provide protection to the facility staff, members of the public, and the environment.
This chapter of the Kairos Power LLC (Kairos) Hermes 2 test reactor construction permit (CP) safety evaluation (SE) describes the U.S. Nuclear Regulatory Commission (NRC) staffs (the staffs) technical review and evaluation of the preliminary information on the radiation protection and waste management programs and design provisions at Hermes 2 as presented in Chapter 11, Radiation Protection and Waste Management, of the Hermes 2 preliminary safety analysis report (PSAR), Revision 1. The staff reviewed PSAR Chapter 11 against applicable regulatory requirements using regulatory guidance and standards to assess the sufficiency of the preliminary information Kairos provided regarding facility radiation protection and waste management for the issuance of CPs in accordance with Title 10, Code of Federal Regulations (10 CFR) Part 50, Domestic Licensing of Production and Utilization Facilities.
As part of this review, the staff evaluated information on the radiation protection and waste management programs and provisions for Hermes 2, with special attention to design and operating characteristics, unusual or novel design features, and principal safety considerations.
The staff evaluated the preliminary design of the Hermes 2 facility radiation protection program and waste management provisions to ensure the design criteria, design bases, and information relative to construction are sufficient to provide reasonable assurance that the final design will conform to the design basis. In addition, the staff reviewed Kaiross identification and justification for the selection of those variables, conditions, or other items which are determined to be probable subjects of technical specifications for the facility, with special attention given to those items which may significantly influence the final design.
The staffs reviews and evaluations for areas relevant to PSAR Chapter 11, including regulations and guidance used, summaries of the application information reviewed, and evaluation findings and conclusions, are discussed in the SE sections below for each of the two major areas of review (radiation protection and waste management) covered in this SE chapter.
A summary and overall conclusion on the staffs technical evaluation of radiation protection and waste management at Hermes 2 are provided in SE Section 11.3, Summary and Conclusions on Radiation Protection and Waste Management.
11.1 Radiation Protection 11.1.1 Introduction Section 11.1, Radiation Protection, of the Hermes 2 PSAR identifies the sources of radiation at the Hermes 2 facility and describes at a high level the programs and provisions for radiation protection and maintaining exposures to radiation as low as is reasonably achievable (ALARA),
including preliminary facility design information relevant to radiation protection.
THIS NRC STAFF DRAFT SE HAS BEEN PREPARED AND IS BEING RELEASED TO SUPPORT INTERACTIONS WITH THE ACRS. THIS DRAFT SE HAS NOT BEEN SUBJECT TO FULL NRC MANAGEMENT AND LEGAL REVIEWS AND APPROVALS, AND ITS CONTENTS SHOULD NOT BE INTERPRETED AS OFFICIAL AGENCY POSITIONS.
11.1.2 Regulatory Evaluation The applicable regulatory requirements for the evaluation of radiation protection at Hermes 2 are as follows:
10 CFR 50.34, Contents of applications; technical information, including:
o 10 CFR 50.34(a)(1)(i), which requires "[a] description and safety assessment of the site on which the facility is to be located, with appropriate attention to features affecting facility design; o 10 CFR 50.34(a)(4), which requires [a] preliminary analysis and evaluation of the design and performance of structures, systems, and components [SSCs] of the facility; and o 10 CFR 50.34(a)(6), which requires [a] preliminary plan for the applicant's organization, training of personnel, and conduct of operations.
10 CFR 50.35, Issuance of construction permits.
10 CFR 50.40, Common standards.
As provided in 10 CFR 20.1002, Scope, the regulations in 10 CFR Part 20, Standards for Protection Against Radiation, apply to persons licensed by the Commission to receive, possess, use, transfer, or dispose of byproduct, source, or special nuclear material or to operate a production or utilization facility. Kairos applied for CPs and has not specifically requested approval of any design information. A CP does not provide a license to operate the facility. In its CP application, Kairos also did not apply for licenses to receive, possess, use, transfer, or dispose of byproduct, source, or special nuclear material at the facility. Therefore, the staff did not evaluate whether requirements in 10 CFR Part 20 would be met for the construction of the Hermes 2 reactor. Instead, the staff assessed whether Kairos had identified the relevant requirements for an operating facility and provided descriptions of the preliminary facility design and provisions for protecting the health and safety of the public, workers, and the environment in sufficient detail to determine whether the PSAR provides an acceptable basis for the development of the radiation protection programs and radioactive waste management, and whether there is reasonable assurance that Kairos will comply with the regulations in 10 CFR Part 20 during operation of the Hermes 2 facility. This is consistent with 10 CFR 50.40(a), which provides that in determining whether CPs may be issued, the Commission will be guided by consideration of reasonable assurance that Kairos will comply with the regulations, including the regulations in 10 CFR Part 20, and that the health and safety of the public will not be endangered.
The applicable guidance for the evaluation of Hermes 2 radiation protection is as follows:
NUREG1537, Guidelines for Preparing and Reviewing Applications for the Licensing of Non-Power Reactors, Part 1, Format and Content, and Part 2, Standard Review Plan and Acceptance Criteria, Section 11.1, Radiation Protection.
11.1.3 Technical Evaluation 11.1.3.1 Radiation Sources PSAR Section 11.1.1, Radiation Sources, identifies the radiation sources that present a potential hazard to workers and the public from operation of the Hermes 2 facility. The generation of the radiation sources is described in general terms. PSAR Table 11.11,
Radiation Sources, lists the SSCs or facility locations which contain fission products or other sources of radiation, with the specific contents identified (e.g., tritium, circulating activity in systems with liquid or gas flow, activation products in structures and components). PSAR Section 11.1.1 states that additional details of radiation sources, including activity and external radiation fields in the facility, will be provided in an operating license (OL) application.
As described in PSAR Section 11.1.5, Radiation Exposure Control and Dosimetry, under subheading Effluent Monitoring, and information from the Hermes 1 review that is applicable to and docketed for Hermes 2 (ML23300A141 and ML23300A144), Kairos performed a conservative screening analysis of gaseous tritium emissions from the Hermes 2 reactors. The screening analysis results yielded projected doses to the public from emissions of tritium from the facility which are well below the allowable limits in 10 CFR Part 20. Kairos used the XOQDOQ atmospheric dispersion model and GASPAR II gaseous effluent pathway model in the NRCDose3 computer code, with site-specific input on the release point, dose receptor locations, and 5 years of site-specific, validated meteorological data. The staff notes that NRCDose3 was developed by the NRC to implement the NRCs ALARA requirements for radioactive effluents from nuclear powerplants.
As described in PSAR Section 11.1.5, analysis assumptions for the tritium effluent release were based on a conservative tritium release rate equal to the generation rate that does not account for retention in the reactor or engineered systems, which would reduce the effective tritium effluent rate. The assumed bounding effluent release quantities for gaseous radionuclide effluents other than tritium were taken from the Clinch River Early Site Permit (ESP)
Environmental Report and were based on light-water small modular reactor preliminary design information. Kairos modeled the release as emanating from a single stack with a high-energy
(>0.4 megawatts) plume at a 100-foot release height, which would bound the release height from the Hermes 2 reactors radionuclide release pathways including the heat energy of the releases from each reactor. The calculated total effective dose equivalent (TEDE) gaseous effluent dose results for each Hermes 2 unit were added together to develop a Hermes 2 facility total, and also further combined with the gaseous effluent dose results for the Hermes 1 reactor to give the site total. The gaseous effluent doses were estimated at two locations: the maximally exposed individual in an unrestricted area and an analytical nearest resident. The estimated combined site total doses from gaseous effluent at these locations are well below the 10 CFR Part 20 public dose limits. The staff confirmed that Kaiross analysis assumptions and methods were consistent with the regulatory guidance identified by Kairos in PSAR Section 11.1.5.
The staff evaluated the sufficiency of the preliminary information on Hermes 2 radiation sources, as described in PSAR Sections 11.1.1 and 11.1.5, using the guidance and acceptance criteria from Section 11.1.1 of NUREG1537, Parts 1 and 2. The staffs review included a comparison of the bases for identifying potential radiation safety hazards with the process and facility descriptions to verify that such hazards were accurately and comprehensively identified.
Based on its review of the information in the PSAR and the information from Hermes 1 that is applicable to and docketed for Hermes 2, the staff finds that the high-level description of radiation sources and their bases, including the effluent screening analysis, is consistent with generation, transport, and cleanup of radionuclides, activation of materials, and radioactive waste production that would occur at the Hermes 2 facility. The staff finds that the results of the effluent screening analysis provide reasonable assurance that 10 CFR Part 20 limits will be met during Hermes 2 operation, including consideration of both the Hermes 1 and Hermes 2 facilities for site total effluent releases. The staff finds use of the Clinch River ESP effluent
information for radionuclides other than tritium to be a reasonable assumption for a preliminary scoping analysis, considering the relative power levels and design differences. The staff will review the effluent analysis corresponding to the detailed design in the application for an OL.
Based on its review, the staff finds the PSAR information on Hermes 2 radiation sources is adequate because it identifies the potential radiation safety hazards associated with the Hermes 2 reactors and provides an acceptable preliminary basis for the development of the radiation protection program. Further, the PSAR information meets the applicable acceptance criteria of NUREG1537, Part 2, Section 11.1.1.
11.1.3.2 Radiation Protection Program and ALARA Program The staff reviewed Sections 11.1.2, Radiation Protection Program, and 11.1.3, ALARA Program, of the Hermes 2 PSAR and compared them to the equivalent sections in the Hermes 1 PSAR (Section 11.1.2, Radiation Protection Program, and Section 11.1.3, ALARA Program). The staff found that Sections 11.1.2 and 11.1.3 of the Hermes 2 PSAR contain information consistent with that in the Hermes 1 PSAR. The staff also verified that the proposed Hermes 2 Radiation Protection Program and ALARA Program remain identical to Hermes 1.
Based on these consistencies, this section incorporates by reference Section 11.1.3.2 of the Hermes 1 SE.
On the basis of its review, the staff finds that the level of detail provided regarding the proposed Hermes 2 radiation protection and ALARA programs demonstrates an adequate basis for a preliminary design and construction permit and satisfies the applicable acceptance criteria of NUREG1537, Part 2, Sections 11.1.2 and 11.1.3, because it identifies applicable requirements and appropriate guidance and general features for implementation of the radiation protection and ALARA programs for the Hermes 2 facility.
11.1.3.3 Radiation Monitoring and Surveying The staff reviewed Section 11.1.4, Radiation Monitoring and Surveying, of the Hermes 2 PSAR and compared it to the equivalent section in the Hermes 1 PSAR (Section 11.1.4, Radiation Monitoring and Surveying). The staff found that Section 11.1.4 of the Hermes 2 PSAR contains information consistent with that in the Hermes 1 PSAR. The staff also verified that the proposed Hermes 2 radiation monitoring and surveying programs remain identical to Hermes 1. Based on these consistencies, this section incorporates by reference Section 11.1.3.3 of the Hermes 1 SE.
On the basis of its review, the staff finds that the level of detail provided regarding the proposed Hermes 2 radiation monitoring and surveying programs demonstrates an adequate basis for a preliminary design and construction permit and satisfies the applicable acceptance criteria of NUREG1537, Part 2, Section 11.1.4, because it identifies applicable requirements for radiation monitoring and surveying, and includes appropriate preliminary information on guidance, practices, and design features to help ensure that Hermes 2 radiation fields and effluents are monitored and sampled as necessary for the Hermes 2 facility.
11.1.3.4 Radiation Exposure Control and Dosimetry The staff reviewed Section 11.1.5 of the Hermes 2 PSAR and compared it to the equivalent section in the Hermes 1 PSAR (Section 11.1.5, Radiation Exposure Control and Dosimetry).
The staff found that Section 11.1.5 of the Hermes 2 PSAR contains information consistent with that in the Hermes 1 PSAR, except for the description of the gaseous effluent analysis, which is
evaluated above in SE Section 11.1.3.1, and minor changes that are evaluated below. The staff also verified that the Hermes 2 radiation exposure control and dosimetry remain similar to Hermes 1. Based on these consistencies, this section incorporates by reference Section 11.1.3.4 of the Hermes 1 SE.
11.1.3.4.1 Minor Changes Compared to the Hermes 1 PSAR The minor changes in Hermes 2 PSAR Section 11.1.5, as compared to the information in Hermes 1 PSAR Section 11.1.5, include the following:
Kairos identified potential gaseous effluent release points for the Hermes 2 reactors that did not exist in the Hermes 1 design.
In Hermes 2 PSAR Section 11.1.5, Kairos states that potential gaseous release points include the power generation system (PGS) evaporator, flash vessel, deaerator, and condenser vent pipe, with a reference to Hermes 2 PSAR Section 9.9, Power Generation System. Hermes 2 PSAR Section 9.9 provides preliminary design information, including sufficient information to confirm the additional potential effluent release points for the Hermes 2 facility which were not a part of the Hermes 1 design. The staffs evaluation of the preliminary design information for the PGS is discussed in Section 9.9 of this SE. Based on the above, the staff finds that the identification of potential gaseous effluent release points is acceptable.
On the basis of its review, the staff finds that the level of detail provided regarding the Hermes 2 radiation exposure control and dosimetry demonstrates an adequate basis for a preliminary design and satisfies the applicable acceptance criteria of NUREG-1537, Part 2, Section 11.1.5.
This finding is based on the fact that the PSAR identifies applicable requirements for radiation exposure control and includes appropriate preliminary information on access controls, shielding, and design features to help ensure that uncontrolled radiation releases and unauthorized entry into high radiation areas will be prevented and radiation doses will be maintained ALARA and within regulatory limits.
11.1.3.5 Contamination Control The staff reviewed Section 11.1.6 of the Hermes 2 PSAR and compared it to the equivalent section in the Hermes 1 PSAR (Section 11.1.6, Contamination Control). The staff found that Section 11.1.6 of the Hermes 2 PSAR contains information consistent with that in the Hermes 1 PSAR. The staff also verified that the Hermes 2 approach to contamination control remains identical to that proposed for Hermes 1. Based on these consistencies, this section incorporates by reference Section 11.1.3.5 of the Hermes 1 SE.
On the basis of its review, the staff finds that the level of detail provided regarding the Hermes 2 approach to contamination control demonstrates an adequate basis for a preliminary design and satisfies the applicable acceptance criteria of NUREG-1537, Part 2, Section 11.1.6, to help ensure that the spread of contamination at Hermes 2 will be minimized.
11.1.3.6 Environmental Monitoring The staff reviewed Section 11.1.7 of the Hermes 2 PSAR and compared it to the equivalent section in the Hermes 1 PSAR (Section 11.1.7, Environmental Monitoring). The staff found that Section 11.1.7 of the Hermes 2 PSAR contains information consistent with that in the Hermes 1 PSAR. The staff also verified that the Hermes 2 approach to environmental
monitoring control remains identical to that proposed for Hermes 1. Based on these consistencies, this section incorporates by reference Section 11.1.3.6 of the Hermes 1 SE.
On the basis of its review, the staff finds that the level of detail provided regarding the Hermes 2 approach to environmental monitoring demonstrates an adequate basis for a preliminary design and satisfies the applicable acceptance criteria of NUREG1537, Part 2, Section 11.1.7, to help ensure any environmental impacts from Hermes 2 operation will be appropriately assessed.
11.1.4 Conclusion Based on its findings above, the staff concludes the information in Hermes 2 PSAR Section 11.1 is sufficient and meets the applicable guidance and regulatory requirements identified in this section for the issuance of CPs in accordance with 10 CFR 50.35 and 10 CFR 50.40. Further information as may be required to complete the review of Hermes 2 radiation protection can reasonably be left for later consideration in the OL application since this information is not necessary for the review of a CP application.
11.2 Radioactive Waste Management 11.2.1 Introduction Section 11.2, Radioactive Waste Management, of the Hermes 2 PSAR describes at a high level the Hermes radioactive waste management program and preliminary facility design information for radioactive waste handling.
11.2.2 Regulatory Evaluation The staff reviewed Section 11.2.2, Regulatory Evaluation, of the Hermes 1 SE for applicability to the Hermes 2 SE. Based on the similarity of the Hermes 1 and Hermes 2 facilities and the consistency of the radioactive waste management approach between Hermes 1 and Hermes 2, the staff finds that the regulations and guidance listed in Section 11.2.2 of the Hermes 1 SE are applicable to Hermes 2. Therefore, this section incorporates by reference Section 11.2.2 of the Hermes 1 SE.
11.2.3 Technical Evaluation The staff reviewed Section 11.2 of the Hermes 2 PSAR and compared it to the equivalent section in the Hermes 1 PSAR (Section 11.2, Radioactive Waste Management). The staff found that Section 11.2 of the Hermes 2 PSAR contains information consistent with that in the Hermes 1 PSAR. The staff also verified that the Hermes 2 radioactive waste management program, radioactive waste handling systems and controls, and release of radioactive waste design and functionality remain identical to Hermes 1. Based on these consistencies, this section incorporates by reference Section 11.2.3 of the Hermes 1 SE.
On the basis of its review, the staff finds that the level of detail provided regarding radioactive waste management for the Hermes 2 facility demonstrates an adequate basis for a preliminary design and satisfies the applicable acceptance criteria of NUREG-1537, Part 2, Section 11.2.
The staff finds that the PSAR provides adequate preliminary information on the radioactive waste management program, radioactive waste handling systems and controls, and release of radioactive waste to help ensure radioactive waste from Hermes 2 will be dispositioned appropriately and in accordance with applicable regulations.
11.2.4 Conclusion Based on the staff findings above, and as incorporated by reference from the Hermes 1 SE, the staff concludes the information in Hermes PSAR Section 11.2 is sufficient and meets the applicable guidance and regulatory requirements identified in this section for the issuance of CPs in accordance with 10 CFR 50.35 and 10 CFR 50.40. Further information as may be required to complete the review of radioactive waste management for the Hermes 2 facility can reasonably be left for later consideration in the OL application since this information is not necessary for the review of a CP application.
11.3 Summary and Conclusions on Radiation Protection and Waste Management The staff evaluated the information on radiation protection and waste management at Hermes 2, as described in PSAR Chapter 11, and finds that the preliminary information and design criteria for the radiation protection and waste management programs and provisions, including the principal design criteria, design bases, and information relating to materials of construction, general arrangement, and approximate dimensions: (1) provide reasonable assurance that the final design will conform to the design bases, (2) meet all applicable regulatory requirements, and (3) meet the applicable acceptance criteria in NUREG1537, Part 2. Based on these findings, the staff makes the following conclusions regarding issuance of CPs in accordance with 10 CFR 50.35 and 10 CFR 50.40:
Kairos has described the proposed facility design for radiation protection and waste management, including, but not limited to, the principal architectural and engineering criteria for the design, and has identified the major features or components incorporated therein for the protection of the health and safety of the public.
Such further technical or design information as may be required to complete the safety analysis of radiation protection and waste management, and which can reasonably be left for later consideration, will be provided in the OL application.
There is reasonable assurance: (i) that the construction of the Hermes 2 facility will not endanger the health and safety of the public, and (ii) that construction activities can be conducted in compliance with the Commissions regulations.
The issuance of permits for the construction of the Hermes 2 facility would not be inimical to the common defense and security or to the health and safety of the public.
11.4 References Kairos Power LLC. KPTR003NPA, "Principal Design Criteria for the Kairos Power Fluoride Salt-Cooled, High Temperature Reactor," Revision 1, June 2020, ML20167A174.
. Submittal of the Environmental Report for the Kairos Power Fluoride Salt-Cooled, High Temperature Non-Power Reactor (Hermes). October 31, 2021. ADAMS Pkg. Accession No. ML21306A131.
. Transmittal of Responses to NRC Requests for Confirmation of Information for the Review of the Hermes Environmental Report. April 22, 2022. ADAMS Pkg. Accession No. ML22115A204.
. Submittal of the Preliminary Safety Analysis Report for the Kairos Power Fluoride Salt-Cooled, High Temperature Non-Power Reactor (Hermes), Revision 3, May 31, 2023, Pkg.
. Transmittal of Response to Hermes 2 General Audit Question 1.5-1, October 27, 2023.
. Kairos Power Response to Hermes 2 General Audit Question 1.5-2, October 27, 2023.
ML23300A144 Nuclear Regulatory Commission (U.S.) (NRC). NUREG1537, Guidelines for Preparing and Reviewing Applications for the Licensing of Non-Power Reactors, Part 1, Format and Content, and Part 2, Standard Review Plan and Acceptance Criteria. NRC: Washington, D.C. February 1996. ADAMS Accession Nos. ML042430055 and ML042430048.
. Regulatory Guide 4.21, Minimization of Contamination and Radioactive Waste Generation: Life-Cycle Planning, Revision 0. NRC: Washington, D.C. June 2008.
. Summary Report for the Regulatory Audit of Kairos Power LLC Hermes Construction Permit Preliminary Safety Analysis Report - General Audit, June 2023, ML23160A287.
, Safety Evaluation Related to the Kairo Power LLC Construction Permit Application for the Hermes Test Reactor, Docket 50-7513, June 13, 2023. ML23158A265.
Tennessee Valley Authority. Clinch River Nuclear Site Early Site Permit Application, Part 3, Environmental Report, Revision 2. January 2019. ADAMS Pkg. Accession No. ML19030A478.
12 CONDUCT OF OPERATIONS The conduct of operations involves the administrative aspects of facility operation (i.e., the facility organizational structure, review and audit activities, facility procedures, required actions for technical specification violations, reporting requirements, and recordkeeping), emergency planning, quality assurance, security, operator training and requalification, and startup and material control and accounting (MC&A) plans.
This chapter of the Kairos Power LLC (Kairos) Hermes 2 construction permit (CP) safety evaluation (SE) describes the U.S. Nuclear Regulatory Commission (NRC) staffs (the staffs) technical review and evaluation of the preliminary information provided in Chapter 12, Conduct of Operations, of the Hermes 2 preliminary safety analysis report (PSAR), Revision 1. The staff reviewed Hermes 2 PSAR Chapter 12 against applicable regulatory requirements using regulatory guidance and standards to assess the sufficiency of the preliminary information on the Hermes 2 conduct of operations for the issuance of CPs in accordance with Title 10, Code of Federal Regulations (10 CFR) Part 50, Domestic Licensing of Production and Utilization Facilities. The staffs reviews and evaluations for areas relevant to PSAR Chapter 12, including regulations and guidance used, a summary of the application information reviewed, and evaluation findings and conclusions, are discussed in the SE sections below for each specific area of review. A summary and overall conclusion on the staffs technical evaluation of the Hermes 2 conduct of operations are provided in SE Section 12.14, Summary and Conclusions on Conduct of Operations.
12.1 Organization 12.1.1 Introduction Section 12.1, Organization, of the Hermes 2 PSAR describes the organizational structure, functional responsibilities, levels of authority, and interfaces for establishing, executing, and verifying the organizational structure concerning facility operation. The organizational structure includes internal and external functions including interface responsibilities for multiple organizations. PSAR Section 12.1 also discusses the organizational aspects of the radiation protection (RP) program, staffing, and selection and training of personnel.
12.1.2 Regulatory Evaluation The staff reviewed Section 12.1.2, Regulatory Evaluation, of the Hermes 1 SE for applicability to the Hermes 2 SE. Based on the similarities between the Hermes 1 and Hermes 2 facilities designs and the consistency of the preliminary organization between Hermes 1 and Hermes 2, the staff finds that the regulations and guidance listed in Section 12.1.2 of the Hermes 1 SE are applicable to Hermes 2. Therefore, this section incorporates by reference Section 12.1.2 of the Hermes 1 SE.
12.1.3 Technical Evaluation The staff reviewed Section 12.1 of the Hermes 2 PSAR and compared it to the equivalent section in the Hermes 1 PSAR (Section 12.1 Organization). The staff found that Section 12.1 of the Hermes 2 PSAR contains information consistent with that in the Hermes 1 PSAR, except for minor changes which are evaluated below. Based on the similarities between the Hermes 1 and Hermes 2 facility designs, the staff finds that the organizational structures, functional THIS NRC STAFF DRAFT SE HAS BEEN PREPARED AND IS BEING RELEASED TO SUPPORT INTERACTIONS WITH THE ACRS. THIS DRAFT SE HAS NOT BEEN SUBJECT TO FULL NRC MANAGEMENT AND LEGAL REVIEWS AND APPROVALS, AND ITS CONTENTS SHOULD NOT BE INTERPRETED AS OFFICIAL AGENCY POSITIONS.
responsibilities, levels of authority, and interfaces for the Hermes 1 facility can be applied to the Hermes 2 facility. Based on these consistencies, this section incorporates by reference Section 12.1.3 of the Hermes 1 SE.
12.1.3.1 Minor Changes Compared to the Hermes 1 PSAR The minor changes in Hermes 2 PSAR Section 12.1, as compared to the information in Hermes 1 PSAR Section 12.1, include the following:
Staffing may be shared to support each of the licensed reactors on the site.
In Hermes 2 PSAR Section 12.1, Kairos states that its staff may be used to perform tasks that support the Hermes 1 and Hermes 2 facilities. Based on its review of the Hermes 2 PSAR, the staff found that the Hermes 2 facility is sufficiently similar to the Hermes 1 facility such that use of the same staff across both facilities would be appropriate for certain functions. The staff anticipates similar staff training and competencies to apply to Hermes 1; Hermes 2, Unit 1; and Hermes 2, Unit 2. Additionally, currently operating power reactor sites that contain multiple units, including those with different plant designs, have had staff that perform certain activities for all units for many decades, demonstrating the validity of this approach. Based on the above, the staff finds that shared staffing between Hermes 1 and Hermes 2 facilities is acceptable.
On the basis of its review, the staff finds that the level of detail provided regarding the Hermes 2 organization demonstrates an adequate basis for a preliminary design and satisfies the applicable acceptance criteria of NUREG1537, Part 2, Section 12.1, Organization.
12.1.4 Conclusion Based on the staff findings above, and as incorporated by reference from the Hermes 1 SE, the staff concludes the information in Hermes 2 PSAR Section 12.1 is sufficient and meets the applicable guidance and regulatory requirements identified in this section for the issuance of CPs in accordance with 10 CFR 50.35, Issuance of construction permits, and 10 CFR 50.40, Common standards. Further information as may be required to complete the review of the Hermes 2 organization (e.g., detailed information on staffing, including control room staffing, and training) can reasonably be left for later consideration in the operating license (OL) application since this information is not necessary to be provided as part of a CP application.
12.2 Review and Audit Activities 12.2.1 Introduction Section 12.2, Review and Audit Activities, of the Hermes 2 PSAR describes review and audit activities during facility operation at Hermes 2.
12.2.2 Regulatory Evaluation The staff reviewed Section 12.2.2, Regulatory Evaluation, of the Hermes 1 SE for applicability to the Hermes 2 SE. Based on the similarities between the Hermes 1 and Hermes 2 facility designs and the consistency of the preliminary information on review and audit activities between Hermes 1 and Hermes 2, the staff finds that the regulations and guidance listed in Section 12.2.2 of the Hermes 1 SE are applicable to Hermes 2. Therefore, this section incorporates by reference Section 12.2.2 of the Hermes 1 SE.
12.2.3 Technical Evaluation The staff reviewed Section 12.2 of the Hermes 2 PSAR and compared it to the equivalent section in the Hermes 1 PSAR (Section 12.2, Review and Audit Activities). The staff found that Section 12.2 of the Hermes 2 PSAR contains information consistent with that in the Hermes 1 PSAR. Based on the similarities between the Hermes 1 and Hermes 2 facilities, the staff found that an identical approach for review and audit activities will be appropriate for Hermes 1 and Hermes 2. Based on these consistencies, this section incorporates by reference Section 12.2.3 of the Hermes 1 SE.
On the basis of its review, the staff finds that the level of detail provided regarding the Hermes 2 review and audit activities demonstrates an adequate basis for a preliminary design and satisfies the applicable acceptance criteria of NUREG1537, Part 2, Section 12.2, Review and Audit Activities.
12.2.4 Conclusion Based on the staff findings above, and as incorporated by reference from the Hermes 1 SE, the staff concludes the information in Hermes 2 PSAR Section 12.2 is sufficient and meets the applicable guidance and regulatory requirements identified in this section for the issuance of CPs in accordance with 10 CFR 50.35 and 10 CFR 50.40. Further information as may be required to complete the review of Hermes 2 review and audit activities (e.g., detailed information on review and audit committee composition, qualifications, charter and rules, and review and audit committee functions including review, approval, audit, and reporting functions) can reasonably be left for later consideration in the OL application since this information is not necessary for the review of a CP application.
12.3 Procedures 12.3.1 Introduction Section 12.3, Procedures, of the Hermes 2 PSAR describes the use of operating procedures during Hermes 2 facility operation.
12.3.2 Regulatory Evaluation The staff reviewed Section 12.3.2, Regulatory Evaluation, of the Hermes 1 SE for applicability to the Hermes 2 SE. Based on the similarities between the Hermes 1 and Hermes 2 facility designs and the consistency of the preliminary information on the proposed approach for procedures between Hermes 1 and Hermes 2, the staff finds that the regulations and guidance listed in Section 12.3.2 of the Hermes 1 SE are applicable to Hermes 2. Therefore, this section incorporates by reference Section 12.3.2 of the Hermes 1 SE.
12.3.3 Technical Evaluation The staff reviewed Section 12.3 of the Hermes 2 PSAR and compared it to the equivalent section in the Hermes 1 PSAR (Section 12.3, Procedures). The staff found that Section 12.3 of the Hermes 2 PSAR contains information consistent with that in the Hermes 1 PSAR. Based on the similarities between Hermes 1 and Hermes 2, the staff found that an identical approach for
procedures will be appropriate for Hermes 1 and Hermes 2. Based on these consistencies, this section incorporates by reference Section 12.3.3 of the Hermes 1 SE.
On the basis of its review, the staff finds that the level of detail provided regarding the Hermes 2 procedures demonstrates an adequate basis for a preliminary design and satisfies the applicable acceptance criteria of NUREG1537, Part 2, Section 12.3.
12.3.4 Conclusion Based on the staff findings above, and as incorporated by reference from the Hermes 1 SE, the staff concludes the information in Hermes 2 PSAR Section 12.3 is sufficient and meets the applicable guidance and regulatory requirements identified in this section for the issuance of CPs in accordance with 10 CFR 50.35 and 10 CFR 50.40. Further information as may be required to complete the review of Hermes 2 procedures (e.g., detailed information on review, approval, and change processes for procedures) can reasonably be left for later consideration in the OL application since this information is not necessary for the review of a CP application.
12.4 Required Actions 12.4.1 Introduction Section 12.4, Required Actions, of the Hermes 2 PSAR describes actions that will be taken when a safety limit is exceeded or a limiting condition for operation or surveillance requirement is not met.
12.4.2 Regulatory Evaluation The staff reviewed Section 12.4.2, Regulatory Evaluation, of the Hermes 1 SE for applicability to the Hermes 2 SE. Based on the similarities between the Hermes 1 and Hermes 2 facility designs and the consistency of the preliminary information regarding required actions between Hermes 1 and Hermes 2, the staff finds that the regulations and guidance listed in Section 12.4.2 of the Hermes 1 SE are applicable to Hermes 2. Therefore, this section incorporates by reference Section 12.4.2 of the Hermes 1 SE.
12.4.3 Technical Evaluation The staff reviewed Section 12.4 of the Hermes 2 PSAR and compared it to the equivalent section in the Hermes 1 PSAR (Section 12.4, Required Actions). The staff found that Section 12.4 of the Hermes 2 PSAR contains information consistent with that in the Hermes 1 PSAR.
Based on the similarities between Hermes 1 and Hermes 2, the staff found that an identical approach to required actions will be appropriate for Hermes 1 and Hermes 2. Based on these consistencies, this section incorporates by reference Section 12.4.3 of the Hermes 1 SE.
Based on its review, the staff determined that the level of detail provided regarding Hermes 2 required actions is adequate and meets the applicable acceptance criteria of NUREG1537, Part 2, Section 12.4, Required Actions.
12.4.4 Conclusion Based on the staff findings above, and as incorporated by reference from the Hermes 1 SE, the staff concludes the information in Hermes 2 PSAR Section 12.4 is sufficient and meets the
applicable guidance and regulatory requirements identified in this section for the issuance of CPs in accordance with 10 CFR 50.35 and 10 CFR 50.40. Further information as may be required to complete the review of Kaiross required actions can reasonably be left for later consideration in the OL application since this information is not necessary for the review of a CP application.
12.5 Reports 12.5.1 Introduction Section 12.5, Reports, of the Hermes 2 PSAR describes required routine operating reports and reporting requirements for changes to the Hermes 2 facility or facility organization to be provided to the NRC.
12.5.2 Regulatory Evaluation The staff reviewed Section 12.5.2, Regulatory Evaluation, of the Hermes 1 SE for applicability to the Hermes 2 SE. Based on the similarities between the Hermes 1 and Hermes 2 facility designs and the consistency of the preliminary information regarding reports between Hermes 1 and Hermes 2, the staff finds that the regulations and guidance listed in Section 12.5.2 of the Hermes 1 SE are applicable to Hermes 2. Therefore, this section incorporates by reference Section 12.5.2 of the Hermes 1 SE.
12.5.3 Technical Evaluation The staff reviewed Section 12.5 of the Hermes 2 PSAR and compared it to the equivalent section in the Hermes 1 PSAR (Section 12.5, Reports). The staff found that Section 12.5 of the Hermes 2 PSAR contains information consistent with that in the Hermes 1 PSAR. Based on the similarities between Hermes 1 and Hermes 2, the staff also finds that an identical approach to reports will be appropriate for Hermes 1 and Hermes 2. Based on these consistencies, this section incorporates by reference Section 12.5.3 of the Hermes 1 SE.
Based on its review, the staff determined that the level of detail provided regarding Hermes 2 reports is adequate and meets the applicable acceptance criteria of NUREG1537, Part 2, Section 12.5, Reports.
12.5.4 Conclusion Based on the staff findings above, and as incorporated by reference from the Hermes 1 SE, the staff concludes the information in Hermes 2 PSAR Section 12.5 is sufficient and meets the applicable guidance and regulatory requirements identified in this section for the issuance of CPs in accordance with 10 CFR 50.35 and 10 CFR 50.40. Further information as may be required to complete the review of Hermes 2 reports can reasonably be left for later consideration in the OL application since this information is not necessary for the review of a CP application.
12.6 Records 12.6.1 Introduction Section 12.6, Records, of the Hermes 2 PSAR describes the process for managing test reactor facility records.
12.6.2 Regulatory Evaluation The staff reviewed Section 12.6.2, Regulatory Evaluation, of the Hermes 1 SE for applicability to the Hermes 2 SE. Based on the similarities between the Hermes 1 and Hermes 2 facility designs and the consistency of the preliminary information on records management between Hermes 1 and Hermes 2, the staff finds that the regulations and guidance listed in Section 12.6.2 of the Hermes 1 SE are applicable to Hermes 2. Therefore, this section incorporates by reference Section 12.6.2 of the Hermes 1 SE.
12.6.3 Technical Evaluation The staff reviewed Section 12.6 of the Hermes 2 PSAR and compared it to the equivalent section in the Hermes 1 PSAR (Section 12.6, Records). The staff found that Section 12.6 of the Hermes 2 PSAR contains information consistent with that in the Hermes 1 PSAR. Based on the similarities between Hermes 1 and Hermes 2 facilities, the staff finds that an identical approach to records management will be appropriate for Hermes 1 and Hermes 2. Based on these consistencies, this section incorporates by reference Section 12.6.3 of the Hermes 1 SE.
Based on its review, the staff determined that the level of detail provided regarding Hermes 2 records is adequate and meets the applicable acceptance criteria of NUREG1537, Part 2, Section 12.6, Records.
12.6.4 Conclusion Based on the staff findings above, and as incorporated by reference from the Hermes 1 SE, the staff concludes the information in Hermes 2 PSAR Section 12.6 is sufficient and meets the applicable guidance and regulatory requirements identified in this section for the issuance of CPs in accordance with 10 CFR 50.35 and 10 CFR 50.40. Further information as may be required to complete the review of Hermes 2 records can reasonably be left for later consideration in the OL application since this information is not necessary for the review of a CP application.
12.7 Emergency Planning 12.7.1 Introduction Section 12.7, Emergency Planning, of the Hermes 2 PSAR discusses emergency planning.
Specifically, the Hermes 2 PSAR provides a description of the preliminary plans for addressing emergencies in PSAR Chapter 12, Appendix A, Description of the Emergency Plan, (i.e.,
PSAR Appendix 12A) which is referenced in PSAR Section 12.7.
12.7.2 Regulatory Evaluation The staff reviewed Section 12.7.2, Regulatory Evaluation, of the Hermes 1 SE for applicability to the Hermes 2 SE. Based on the similarities between the Hermes 1 and Hermes 2 facility designs and consistency of the preliminary information related to the emergency planning approach between Hermes 1 and Hermes 2, the staff finds that the regulations and guidance listed in Section 12.7.2 of the Hermes 1 SE are applicable to Hermes 2. Therefore, this section incorporates by reference Section 12.7.2 of the Hermes 1 SE.
12.7.3 Technical Evaluation The staff reviewed Section 12.7 and Appendix 12A of the Hermes 2 PSAR and compared it to the equivalent sections in the Hermes 1 PSAR (Section 12.7, Emergency Planning and Appendix A, Description of the Emergency Plan). The staff found that Section 12.7 and Appendix 12A of the Hermes 2 PSAR contain information consistent with that in the Hermes 1 PSAR, except for a minor change which is evaluated below. The staff also verified that the Hermes 2 preliminary plans for addressing emergencies remain identical to Hermes 1. Based on these consistencies, this section incorporates by reference Section 12.7.3 of the Hermes 1 SE.
12.7.3.1 Minor Change Compared to the Hermes 1 PSAR The minor change in Hermes 2 PSAR, Appendix 12A, Section G, Evacuation, as compared to the information in Hermes 1 PSAR, Appendix 12A, Section G, Evacuation, includes the following:
Language clarifying that Hermes 2 is a test reactor facility.
In Hermes 2 PSAR, Appendix 12A, Section G, Kairos states that the facility is licensed as a test reactor. While this text differs slightly from the equivalent section in the Hermes 1 PSAR, the intent remains the same (i.e., to reinforce that certain regulatory requirements do not apply to test facilities). This minor change has no impact on the Hermes 2 preliminary plans for addressing facility emergencies. Based on the above, the staff finds that the clarifying language is acceptable.
On the basis of its review, the staff finds that the level of detail provided regarding the Hermes 2 preliminary plans for addressing emergencies satisfies the applicable acceptance criteria of NUREG-1537, Part 2, Section 12.7, the applicable guidance in American Nuclear Standards Institute/American Nuclear Society-15.16-2015, Emergency Planning for Research Reactors, the applicable guidance evaluation items contained in NUREG-0849, Standard Review Plan for the review and Evaluation of Emergency Plans for Research and Test Reactors, and are also consistent with the guidance in Regulatory Guide 2.6, Emergency Planning for Research and Test Reactors and Other Non-Power Production and Utilization Facilities, Revision 2, as applicable.
12.7.4 Conclusion Based on the staff findings above, and as incorporated by reference from the Hermes 1 SE, the staff concludes that Kaiross preliminary plans for coping with emergencies are sufficient and comply with the applicable requirements of 10 CFR 50.34(a), including 10 CFR 50.34(a)(10),
which requires that the PSAR include [a] discussion of the applicants preliminary plans for
coping with emergencies, 10 CFR 50.35, 10 CFR 50.40, and 10 CFR Part 50, Appendix E, Emergency Planning and Preparedness for Production and Utilization Facilities,Section I, Introduction, and Section II, The Preliminary Safety Analysis Report. Further information as may be required to complete the review of Hermes 2 emergency planning can reasonably be left for later consideration in the OL application since this information is not necessary for the review of a CP application.
12.8 Security 12.8.1 Introduction Section 12.8, Security, of the Hermes 2 PSAR provides preliminary information regarding security planning for the Hermes 2 facility.
12.8.2 Regulatory Evaluation The staff reviewed Section 12.8.2, Regulatory Evaluation, of the Hermes 1 SE for applicability to the Hermes 2 SE. Based on the similarities between the Hermes 1 and Hermes 2 facility designs and consistency of the preliminary information related to the security approach between Hermes 1 and Hermes 2, the staff finds that the regulations and guidance listed in Section 12.8.2 of the Hermes 1 SE are applicable to Hermes 2. Therefore, this section incorporates by reference Section 12.8.2 of the Hermes 1 SE.
12.8.3 Technical Evaluation The staff reviewed Section 12.8 of the Hermes 2 PSAR and compared it to the equivalent section in the Hermes 1 PSAR (Section 12.8, Security). The staff found that Section 12.8 of the Hermes 2 PSAR contains information consistent with that in the Hermes 1 PSAR. The staff also verified that the Hermes 2 security planning approach remains identical to that proposed for Hermes 1. Based on these consistencies, this section incorporates by reference Section 12.8.3 of the Hermes 1 SE.
On the basis of its review, the staff finds that the level of detail provided regarding security planning for the Hermes 2 facility is adequate and satisfies the applicable acceptance criteria of NUREG1537, Part 2, Section 12.8, Security Planning.
12.8.4 Conclusion Based on the staff findings above, and as incorporated by reference from the Hermes 1 SE, the staff concludes the information in Hermes 2 PSAR Section 12.8 is sufficient and meets the applicable guidance and regulatory requirements identified in this section for the issuance of CPs in accordance with 10 CFR 50.35 and 10 CFR 50.40. Further information as may be required to complete the review of Hermes 2 security planning can reasonably be left for later consideration in the OL application since this information is not necessary for the review of a CP application.
12.9 Quality Assurance 12.9.1 Introduction Section 12.9, Quality Assurance, of the Hermes 2 PSAR describes quality assurance (QA) for the Hermes 2 facility, and states that the description of Kaiross QA program for the design, construction, and operation of Hermes 2 is based on ANSI/ANS 15.81995 (R2005), Quality Assurance Program Requirements for Research Reactors, and the guidance in RG 2.5, Quality Assurance Program Requirements for Research and Test Reactors, Revision 1. Kairos provided its Quality Assurance Program Description (QAPD) as Appendix B to PSAR Section 12 (i.e., PSAR Appendix 12B).
12.9.2 Regulatory Evaluation The staff reviewed Section 12.9.2, Regulatory Evaluation, of the Hermes 1 SE for applicability to the Hermes 2 SE. Based on the similarities between the Hermes 1 and Hermes 2 facility designs and the consistency of the QA program between Hermes 1 and Hermes 2, the staff finds that the regulations and guidance listed in Section 12.9.2 of the Hermes 1 SE are applicable to Hermes 2. Therefore, this section incorporates by reference Section 12.9.2 of the Hermes 1 SE.
12.9.3 Technical Evaluation The staff reviewed Section 12.9, Quality Assurance and Appendix 12B, Quality Assurance Program, of the Hermes 2 PSAR and compared them to the equivalent sections in the Hermes 1 PSAR (Section 12.9, Quality Assurance and Appendix 12B, Quality Assurance Program). The staff found that Section 12.9 and Appendix 12B of the Hermes 2 PSAR contain information consistent with that in the Hermes 1 PSAR, except for a minor change which is evaluated below. The staff also verified that the approach to QA remains identical to Hermes 1.
Based on these consistencies, this section incorporates by reference Section 12.9.3 of the Hermes 1 PSAR.
12.9.3.1 Minor Change Compared to the Hermes 1 PSAR The minor change in Hermes 2 PSAR Section 12.9, as compared to the information in Hermes 1 PSAR Section 12.9, includes the following:
An additional sentence noting that the QAPD provided in Appendix 12B was written for Hermes 1 but is also applicable to Hermes 2.
The QAPD provided in the Hermes 2 PSAR, Appendix 12B, is identical to the QAPD provided in the Hermes 1 PSAR, Appendix 12B, and is also titled the same. The information contained in the QAPD is independent of the facility differences between Hermes 1 and Hermes 2.
Therefore, the same QAPD is applicable to both Hermes 1 and Hermes 2. Based on the above, the staff finds that use of the Hermes 1 QAPD for Hermes 2 is acceptable.
On the basis of its review, the staff finds that the QAPD discussed in PSAR Section 12.9 and provided in PSAR Appendix 12B demonstrates an adequate basis for a preliminary design and satisfies the guidance relevant to design, fabrication, construction, and testing in Sections 1 and 2 of ANSI/ANS 15.81995, which the NRC endorsed in RG 2.5, Revision 1, and that the
QAPD is also consistent with the guidance contained within NUREG1537, Part 2, Section 12.9, Quality Assurance.
12.9.4 Conclusion Based on the staff findings above, and as incorporated by reference from the Hermes 1 SE, the staff concludes that the Hermes 2 QAPD is sufficient and complies with the requirements of 10 CFR 50.34(a)(7), which requires, in part, that an applicant for a CP provide a description of the QA program to be applied to the design, fabrication, construction, and testing of the SSCs of the facility. Accordingly, the staff concludes that the information in PSAR Section 12.9 and PSAR Appendix 12B is sufficient and meets the applicable guidance and regulatory requirements identified in this section for the issuance of CPs in accordance with 10 CFR 50.35 and 10 CFR 50.40, and, as such, the Hermes 2 QAPD is acceptable for implementation during the design and construction of the Hermes 2 facility. Further information as may be required to complete the review of Kaiross QA program for the conduct of operations and decommissioning can reasonably be left for later consideration in the OL application (or a proposed decommissioning plan, as appropriate) since this information is not necessary for the review of a CP application.
Paragraph 50.55(f) of 10 CFR requires, in part, that a nuclear power plant or fuel reprocessing plant CP holder implement the QA program described in its safety analysis report. Because the Hermes 2 facility is neither a nuclear power plant nor a fuel reprocessing plant, the requirements of 10 CFR 50.55(f) would not apply to Hermes 2. Therefore, the staff recommends that the CPs include the permit condition provided below to: (1) ensure consistency in expectations for Kaiross implementation of its QA program developed pursuant to 10 CFR 50.34(a)(7); (2) establish criteria for changes to the QA program and for the notifications Kairos must make to the NRC regarding such changes; and (3) facilitate the correction of any identified deficiencies in the implementation of the QA program through the NRCs enforcement process during construction inspection. The permit condition is as follows:
Kairos shall implement the QA program described, pursuant to 10 CFR 50.34(a)(7), in Chapter 12, Appendix B, of Revision 1 of the Hermes 2 PSAR, including revisions to the QA program in accordance with the provisions below.
Kairos may make changes to its previously accepted QA program description without prior Commission approval, provided the changes do not reduce the commitments in the QA program description as accepted by the Commission. Changes to the QA program description that do not reduce the commitments must be submitted to the Commission within 90 days.
Changes to the QA program description that do reduce the commitments must be submitted to the Commission and receive Commission approval prior to implementation, as follows:
Changes must be submitted as specified in 10 CFR 50.4.
The submittal of changes to the QA program description must include all pages affected by the changes and must be accompanied by a forwarding letter identifying the changes, the reason for the changes, and the basis for concluding that the revised program incorporating the changes continues to satisfy the PSAR Revision 1 QA program description commitments previously accepted by
the NRC (the letter need not provide the basis for changes that correct spelling, punctuation, or editorial items).
A copy of the forwarding letter identifying the changes must be maintained as a record by Kairos for three years.
Changes to the QA program description shall be regarded as accepted by the Commission upon Kaiross receipt of a letter to this effect from the appropriate reviewing office of the Commission or 60 days after Kaiross submittal to the Commission, whichever occurs first.
12.10 Operator Training and Requalification 12.10.1 Introduction Section 12.10, Reactor Operating Training and Requalification, of the Hermes 2 PSAR provides preliminary information on Hermes 2 operator training and requalification.
12.10.2 Regulatory Evaluation The staff reviewed Section 12.10.2, Regulatory Evaluation, of the Hermes 1 SE for applicability to the Hermes 2 SE. Based on the similarities between the Hermes 1 and Hermes 2 facility designs and the consistency of the preliminary information related to the operator training and requalification approaches between Hermes 1 and Hermes 2, the staff finds that the regulations and guidance listed in Section 12.10.2 of the Hermes 1 SE are applicable to Hermes
- 2. Therefore, this section incorporates by reference Section 12.10.2 of the Hermes 1 SE.
12.10.3 Technical Evaluation The staff reviewed Section 12.10 of the Hermes 2 PSAR and compared it to the equivalent section in the Hermes 1 PSAR (Section 12.10, Reactor Operator Training and Requalification).
The staff found that Section 12.10 of the Hermes 2 PSAR contains information consistent with that in the Hermes 1 PSAR. The staff also verified that the Hermes 2 approaches to reactor operator training and requalification for the CP application remain identical to Hermes 1. Based on these consistencies, this section incorporates by reference Section 12.10.3 of the Hermes 1 SE.
Based on its review, the staff determined that the level of detail provided regarding Hermes 2 operator training and requalification is adequate and meets the applicable acceptance criteria of NUREG1537, Part 2, Section 12.10, Operator Training and Requalification.
12.10.4 Conclusion Based on the staff findings above, and as incorporated by reference from the Hermes 1 SE, the staff concludes the information in Hermes 2 PSAR Section 12.10 is sufficient and meets the applicable guidance and regulatory requirements identified in this section for the issuance of CPs in accordance with 10 CFR 50.35 and 10 CFR 50.40. Further information as may be required to complete the review of Hermes 2 operator training and requalification can reasonably be left for later consideration in the OL application since this information is not necessary for the review of a CP application.
12.11 Startup Plan 12.11.1 Introduction Section 12.11, Startup Plan, of the Hermes 2 PSAR discusses the Hermes 2 startup plan.
12.11.2 Regulatory Evaluation The staff reviewed Section 12.11.2, Regulatory Evaluation, of the Hermes 1 SE for applicability to the Hermes 2 SE. Based on the similarities between the Hermes 1 and Hermes 2 facility designs and the consistency of the preliminary information related to a startup plan between Hermes 1 and Hermes 2, the staff finds that the regulations and guidance listed in Section 12.11.2 of the Hermes 1 SE are applicable to Hermes 2. Therefore, this section incorporates by reference Section 12.11.2 of the Hermes 1 SE.
12.11.3 Technical Evaluation The staff reviewed Section 12.11 of the Hermes 2 PSAR and compared it to the equivalent section in the Hermes 1 PSAR (Section 12.11, Startup Plan). The staff found that Section 12.11 of the Hermes 2 PSAR contains information consistent with that in the Hermes 1 PSAR.
Based on the similarities between Hermes 1 and Hermes 2, the staff found that a generally similar approach for the startup plan will be appropriate for Hermes 1 and Hermes 2 (i.e., that the startup plan for both facilities would be provided as part of an OL application). Based on these consistencies, this section incorporates by reference Section 12.11.3 of the Hermes 1 SE.
Based on its review, the staff determined that the level of detail provided regarding a Hermes 2 startup plan is adequate and meets the applicable acceptance criteria of NUREG1537, Part 2, Section 12.11, Startup Plan.
12.11.4 Conclusion Based on the staff findings above, and as incorporated by reference from the Hermes 1 SE, the staff concludes the information in Hermes 2 PSAR Section 12.11 is sufficient and meets the applicable guidance and regulatory requirements identified in this section for the issuance of CPs in accordance with 10 CFR 50.35 and 10 CFR 50.40. Further information as may be required to complete the review of a Hermes 2 startup plan can reasonably be left for later consideration in the OL application since this information is not necessary for the review of a CP application.
12.12 Environmental Report Kairos did not provide, and the staff did not review, environmental information in the PSAR as described in Section 12.12, Environmental Reports, of NUREG1537, Parts 1 and 2. In lieu of providing environmental information in the PSAR, Kairos provided environmental information in an Environmental Report submitted as part of the CP application on July 14, 2023. The staffs evaluation of Kaiross environmental information will be documented in a Draft Environmental Assessment.
12.13 Material Control and Accounting Plan NUREG1537, Parts 1 and 2, do not include guidance or acceptance criteria for MC&A plans.
Furthermore, Kairos did not provide, and the staff did not review, a MC&A plan in the PSAR.
While MC&A is not discussed in the PSAR, PSAR Section 9.6, Possession and Use of Byproduct, Source, and Special Nuclear Material, states that Kairos plans to request authorization to possess special nuclear material (SNM) pursuant to 10 CFR Part 70, Domestic Licensing of Special Nuclear Material in the future. The staff notes that licensees possessing SNM must comply with the applicable requirements of 10 CFR Part 74, Material Control and Accounting of Special Nuclear Material.
During the Hermes 2 General Audit, Kairos confirmed via its answer to audit question 1.5-2 (ML23300A144) that it will take the same approach as for Hermes 1 and provide an MC&A plan with a Hermes 2 OL application or other licensing submittal (e.g., a CP amendment) requesting authorization to possess SNM, as appropriate.
Because the CP application does not request authorization to possess SNM, and because information on MC&A is not required for an applicant that does not request authorization to possess SNM, the staff finds that it is acceptable that the Hermes 2 PSAR does not include information on MC&A. Information on MC&A at the facility can reasonably be left for later consideration in a Hermes 2 OL application or other licensing submittal requesting authorization to possess SNM, as appropriate.
12.14 Summary and Conclusions on the Conduct of Operations The staff evaluated the information on the Hermes 2 conduct of operations as described in PSAR Chapter 12 and finds that the preliminary plans and information on the Hermes 2 conduct of operations: (1) meet all applicable regulatory requirements and (2) meet the applicable acceptance criteria in NUREG1537, Part 2, allowing the staff to make findings that:
Kaiross preliminary information and commitments to develop the Hermes 2 organization, review and audit programs, procedures, required actions, reporting and recordkeeping requirements, security plan, and operator training and requalification plans are sufficient and meet the applicable regulatory requirements and guidance for the issuance of CPs. Further information on these items can reasonably be left for later consideration in the OL application.
Information on the Hermes 2 startup plan and MC&A plan can reasonably be left for later consideration in the OL application.
The preliminary information on emergency planning is sufficient and meets the applicable regulatory requirements and guidance for the issuance of CPs. Further information can reasonably be left for later consideration in the final safety analysis report (FSAR) and updated emergency plan submitted with an OL application.
The Hermes 2 QAPD is sufficient and meets the applicable regulatory requirements and guidance for the issuance of CPs. Further information related to QA during operations and decommissioning can reasonably be left for later consideration during future reviews of a Hermes 2 OL application and proposed decommissioning plan, respectively.
Based on these findings and subject to the condition referenced above, the staff concludes the following regarding the issuance of CPs in accordance with 10 CFR 50.35 and 10 CFR 50.40:
Such further technical or design information as may be required to complete the safety analysis, and which can reasonably be left for later consideration, will be supplied in the FSAR.
There is reasonable assurance: (i) that the construction of the Hermes 2 facility will not endanger the health and safety of the public, and (ii) that construction activities can be conducted in compliance with the Commissions regulations.
Kairos is technically qualified to engage in the construction of its proposed Hermes 2 facility in accordance with the Commissions regulations.
The issuance of permits for the construction of the Hermes 2 facility would not be inimical to the common defense and security or to the health and safety of the public.
12.15 References American Nuclear Society. American National Standards Institute/American Nuclear Society (ANSI/ANS)-15.81995, Quality Assurance Programs Requirements for Research Reactors, American Nuclear Society, La Grange Park, Illinois.
. ANSI/ANS-15.12007, The Development of Technical Specifications for Research Reactors, American Nuclear Society, La Grange Park, Illinois.
. ANSI/ANS-15.162015, Emergency Planning for Research Reactors, American Nuclear Society, La Grange Park, Illinois.
. ANSI/ANS-15.42016, Selection and Training of Personnel for Research Reactors, American Nuclear Society, La Grange Park, Illinois.
Kairos Power LLC. Submittal of the Environmental Report for the Kairos Power Fluoride Salt-Cooled, High Temperature Non-Power Reactor (Hermes). October 31, 2021. ADAMS Pkg.
. Submittal of the Preliminary Safety Analysis Report for the Kairos Power Fluoride Salt-Cooled, High Temperature Non-Power Reactor (Hermes), Revision 3, May 31, 2023, Pkg.
. Kairos Power Response to Hermes 2 General Audit Question 1.5-2, October 27, 2023.
. Submittal of the Construction Permit Application for the Hermes 2 Kairos Power Fluoride Salt-Cooled, High Temperature Non-Power Reactor, Revision 1, [month] xx, 2024, Pkg.
MLxxxxxxxxx.
Nuclear Regulatory Commission (U.S.) (NRC). Regulatory Guide 5.59, Standard Format and Content for a Licensee Physical Security Plan for the Protection of Special Nuclear Material, Revision 1. NRC: Washington, D.C. February 1983. ML100341301.
. NUREG-0849, Standard Review Plan for the Review and Evaluation of Emergency Plans for Research and Test Reactors, NRC: Washington, D.C. October 1983. ML062190191.
. NUREG1537, Guidelines for Preparing and Reviewing Applications for the Licensing of Non-Power Reactors, Part 1, Format and Content, and Part 2, Standard Review Plan and Acceptance Criteria. NRC: Washington, D.C. February 1996. ADAMS Accession Nos.
ML042430055 and ML042430048.
. Regulatory Guide 2.5, Quality Assurance Program Requirements for Research and Test Reactors, Revision 1. NRC: Washington, D.C. June 2010. ML093520099.
. Regulatory Guide 2.6, Emergency Planning for Research and Test Reactors and Other Non-Power Production and Utilization Facilities. Revision 2. NRC: Washington, D.C. 2017.
. Draft Environmental Impact Statement for Construction Permit for the Kairos Hermes Testing Reactor. NRC: Washington, D.C. September 2022. ML22259A126.
. Summary Report for the Regulatory Audit of Kairos Power LLC Hermes Construction Permit Preliminary Safety Analysis Report - General Audit, June 2023, ML23160A287.
. Safety Evaluation Related to the Kairo Power LLC Construction Permit Application for the Hermes Test Reactor, Docket 50-7513, June 13, 2023. ML23158A265.
. Draft Environmental Assessment for Construction Permit for the Kairos Hermes 2 Testing Reactor. NRC: Washington, D.C. [month] xx 2024, MLxxxxxxxxx.
14 TECHNICAL SPECIFICATIONS The principal purpose of technical specifications (TSs) is to maintain system performance and ensure safe reactor operation. This is accomplished by including in the TSs limiting or enveloping conditions of design and operation, ensuring that emphasis is placed on the safety of the public, the facility staff, and the environment. TSs are typically derived from the facility descriptions and safety considerations contained in the facility safety analysis report.
This chapter of the Kairos Power LLC (Kairos) Hermes 2 construction permit (CP) safety evaluation describes the U.S. Nuclear Regulatory Commission (NRC) staffs (the staffs) technical review and evaluation of the probable subjects of TSs for the Hermes 2 facility as presented in preliminary safety analysis report (PSAR), Revision 1, Chapter 14, Technical Specifications.
14.1 Introduction Hermes 2 PSAR Chapter 14 provides preliminary information on Hermes 2 facility TSs that will be applicable for various operating modes during Hermes 2 operation. In PSAR Section 14.1, Introduction, Kairos discusses the general format and content of the TSs as well as variables and conditions that are expected to be the subjects of TSs. Kairos also discusses some probable subjects of TSs in other PSAR chapters. Kairos does not provide actual TSs in the PSAR; PSAR Section 14.1 states that the Hermes 2 TSs will be provided in an operating license (OL) application. In PSAR Section 14.2, Operating Modes, Kairos summarizes the five different Hermes 2 operating modes for the Hermes 2 TSs.
14.2 Regulatory Evaluation The staff reviewed Section 14.2, Regulatory Evaluation, of the Hermes 1 SE for applicability to the Hermes 2 SE. Based on the similarities between the Hermes 1 and Hermes 2 facilities and the consistency of the proposed subjects of TSs between Hermes 1 and Hermes 2, the staff finds that the regulations and guidance listed in Section 14.2 of the Hermes 1 SE are applicable to Hermes 2. Therefore, this section incorporates by reference Section 14.2 of the Hermes 1 SE.
14.3 Technical Evaluation The staff reviewed Chapter 14 of the Hermes 2 PSAR and compared it to the equivalent material in the Hermes 1 PSAR (Chapter 14, Technical Specifications). The staff found that the Hermes 2 PSAR contains information consistent with that in the Hermes 1 PSAR, except for a few minor changes and a few significant changes, which are evaluated below in Sections 14.3.1 and 14.3.2, respectively. The staff found that the following portions of Chapter 14 in the Hermes 2 PSAR contain information consistent with the Hermes 1 PSAR (e.g., minor or editorial changes only):
Sections 14.1, Introduction, through 14.3, References Table 14.1-1, Proposed Variables and Conditions for Technical Specifications, Sections 2.0 through 3.2, and Sections 3.4 through 6.0 Table 14.2-1, Operating MODES for Technical Specifications THIS NRC STAFF DRAFT SE HAS BEEN PREPARED AND IS BEING RELEASED TO SUPPORT INTERACTIONS WITH THE ACRS. THIS DRAFT SE HAS NOT BEEN SUBJECT TO FULL NRC MANAGEMENT AND LEGAL REVIEWS AND APPROVALS, AND ITS CONTENTS SHOULD NOT BE INTERPRETED AS OFFICIAL AGENCY POSITIONS.
Since the Hermes 2 system design and functionality largely remain identical, excepting the differences evaluated below, there are few changes to the proposed TSs in Chapter 14 of the Hermes 2 PSAR when compared to Chapter 14 of the Hermes 1 PSAR. Based on these consistencies, this section incorporates by reference Section 14.3 of the Hermes 1 SE.
14.3.1 Minor Changes Compared to the Hermes 1 PSAR The minor changes in Hermes 2 PSAR Sections 14.1 and 14.2, Operating Modes, as compared to the information in Hermes 1 PSAR Sections 14.1 and 14.2, include the following:
Clarification that the TS variables and conditions apply to both Hermes 2 units Clarification that the operating modes apply to both Hermes 2 units In Hermes 2 PSAR Section 14.1, Kairos clarifies that the proposed TS variables and conditions listed in Hermes 2 PSAR Table 14.1-1 apply to both Unit 1 and Unit 2. In Section 14.2 of the Hermes 2 PSAR, Kairos clarifies that the operating modes listed in Table 14.2-1 are applicable to both Unit 1 and Unit 2. The staff finds that these clarifications are appropriate for the two-unit Hermes 2 facility because all reactors must have TSs and the two units are proposed to be identical.
Similar to the Hermes 1 PSAR, other Hermes 2 PSAR chapters discuss additional probable subjects of TSs including shutdown margin, moderator pebble to fuel pebble ratio, and fuel enrichment (Hermes 1 PSAR Section 4.5.4.2, Testing and Monitoring, and Hermes 2 PSAR Section 4.5.4.2, Testing and Monitoring), and pebble burnup limits (Hermes 1 PSAR Section 9.3.4, Testing and Inspection, and Hermes 2 PSAR Section 9.3.4, Testing and Inspection).
The staff assumes that other proposed TSs discussed in the Hermes 2 PSAR would also apply to both Unit 1 and Unit 2 because the units are identical. Based on the above, the staff finds that the clarifications are acceptable.
14.3.2 Significant Changes Compared to the Hermes 1 PSAR Significant changes contained in Chapter 14 of the Hermes 2 PSAR, as compared to Chapter 14 of the Hermes 1 PSAR, include information regarding additional proposed limiting conditions for operation (LCOs) for the following structures, systems, and components that are added in Hermes 2 and were not included in the design of Hermes 1:
Intermediate heat transport system (IHTS), and Power generation system (PGS).
These changes are identified in Section 3.3, Coolant Systems, of Hermes 2 PSAR Table 14.1-1. The additional proposed LCOs for the IHTS address a limit on the quantities of radioactive material at risk (MAR) in the IHTS, operability of IHTS rupture disks, and limits on the quantities of Flibe and water in the IHTS salt coolant. The additional proposed LCO for the PGS addresses a limit on the quantities of MAR in the PGS. During the General Audit, Kairos confirmed that all the MAR in the IHTS (i.e., in both the IHTS cover gas and coolant) and all the MAR in the PGS (i.e., in both steam and water) will be addressed by the proposed TSs.
The staff evaluated the sufficiency of this additional preliminary information in Hermes 2 PSAR Chapter 14 on the Hermes 2 TS using the guidance and acceptance criteria from Chapter 14,
Technical Specifications, of NUREG1537, Guidelines for Preparing and Reviewing Applications for the Licensing of Non-Power Reactors, Parts 1 and 2. In its evaluation, the staff also considered the preliminary safety analysis information in other Hermes 2 PSAR Chapters.
The staff finds Kaiross addition of the IHTS and PGS parameters discussed above as probable subjects of TS LCOs to be acceptable. This acceptance is based on the staffs conclusion that Kairos has adequately identified probable subjects of TSs that are consistent with important parameters determined as a result of the preliminary safety analyses in the PSAR. Additionally, the staff concluded that Kairos gave special attention to items (e.g., safety limits, limiting safety system settings, and LCOs) that may significantly influence the final design, and that the probable subjects of TSs are supported by appropriate bases. The staff expects that additional subjects of TSs will likely be needed, but finds that other probable subjects of TSs beyond those specifically listed in PSAR Chapter 14 are, in general, less likely to significantly influence the final design.
Therefore, based on the information in Hermes 2 PSAR Chapter 14 and other PSAR chapters, the staff finds that Kaiross identification and justification of the probable subjects of TSs meets the applicable acceptance criteria in Chapter 14 of NUREG1537. The staff will perform a detailed evaluation of the complete and finalized TSs for Hermes 2, including safety limits, limiting safety system settings, LCOs, surveillance requirements, design features, and administrative controls, during its review of a Hermes 2 OL application.
14.4 Conclusion Based on the staff findings above, and as incorporated by reference from the Hermes 1 SE, the staff concludes the information in Chapter 14 of the Hermes 2 PSAR is sufficient and meets the applicable guidance and regulatory requirements identified in this section for the issuance of CPs in accordance with 10 CFR 50.35 and 10 CFR 50.40. Further information, including a complete set of Hermes 2 TSs and associated bases, as may be required to complete the review of a Hermes 2 OL application can reasonably be left for later consideration in a final safety analysis report since this information is not necessary for the review of a CP application.
14.5 Summary and Conclusions on Technical Specifications The staff evaluated the information on the Hermes 2 TSs as described in PSAR Chapter 14 and finds that the preliminary TS methodology: (1) meets all applicable regulatory requirements, and (2) meets the applicable acceptance criteria in Chapter 14 of NUREG1537, Part 2. Based on these findings, the staff makes the following conclusions regarding issuance of CPs in accordance with 10 CFR 50.35 and 10 CFR 50.40:
Kairos has described the proposed design of the facility, including, but not limited to, the principal engineering criteria for the design, and has identified the major features or components incorporated therein for the protection of the health and safety of the public.
Such further technical or design information as may be required to complete the safety evaluation of the Hermes 2 TSs, and which can reasonably be left for later consideration, will be provided in the final safety analysis report.
There is reasonable assurance: (i) that the construction of the facility will not endanger the health and safety of the public, and (ii) that construction activities will be conducted in compliance with the Commissions regulations.
The issuance of permits for the construction of the Hermes 2 facility would not be inimical to the common defense and security or to the health and safety of the public.
14.6 References American National Standards Institute/American Nuclear Society (ANSI/ANS)-15.12007, The Development of Technical Specifications for Research Reactors, American Nuclear Society, La Grange Park, Illinois.
Kairos Power LLC, Fuel Qualification Methodology for the Kairos Power Fluoride Salt-Cooled High Temperature Reactor (KP-FHR), KPTR011NP-A, Revision 2, June 2022, ML23089A398 (redacted version).
. Submittal of the Preliminary Safety Analysis Report for the Kairos Power Fluoride Salt-Cooled, High Temperature Non-Power Reactor (Hermes), Revision 3, May 31, 2023, Pkg.
Nuclear Regulatory Commission (U.S.) (NRC). NUREG1537, Guidelines for Preparing and Reviewing Applications for the Licensing of Non-Power Reactors, Part 1, Format and Content, and Part 2, Standard Review Plan and Acceptance Criteria. NRC: Washington, D.C. February 1996. ADAMS Accession Nos. ML042430055 and ML042430048.
. Summary Report for the Regulatory Audit of Kairos Power LLC Hermes Construction Permit Preliminary Safety Analysis Report - General Audit, June 2023, ML23160A287.
. Safety Evaluation Related to the Kairo Power LLC Construction Permit Application for the Hermes Test Reactor, Docket 50-7513, June 13, 2023. ML23158A265.
. Summary Report for the Regulatory Audit of Kairos Power LLC Hermes 2 Construction Permit Preliminary Safety Analysis Report - General Audit, [month] xx, 2024, MLXXXXXXXXX
16 OTHER LICENSE CONSIDERATIONS The Kairos Power LLC (Kairos) Hermes 2 preliminary safety analysis report (PSAR), Revision 1 Chapter 16, Other License Considerations, Section 16.1, Prior Use of Facility Components, states that the Hermes 2 facility will be constructed of new and appropriately qualified structures, systems, and components to conduct operations. Discussions regarding used systems and components are not applicable to the facility. Additionally, in PSAR Section 16.2, Medical Use of Non-Power Reactors, Kairos states that the Hermes 2 facility will not contain equipment or facilities associated with direct medical administration of radioisotopes or other radiation-based therapies and [Kairos] has no plans at this time to support medical uses.
Therefore, discussions involving medical use of the facility are not applicable. PSAR Chapter 16 does not identify any other special license considerations that are not discussed elsewhere in the PSAR.
The U.S. Nuclear Regulatory Commission (NRC) staff (the staff) evaluated the information on the Hermes 2 facility in the PSAR and finds that the preliminary design of the Hermes 2 facility does not include prior use components and that the Hermes 2 facility will not be used for direct medical therapy. Furthermore, the staff did not identify any other special license considerations relevant to Hermes 2 that are not addressed elsewhere in the PSAR and considered in other chapters of this safety evaluation (SE), as appropriate. The staff concludes that an evaluation using the guidelines of NUREG1537, Guidelines for Preparing and Reviewing Applications for the Licensing of Non-Power Reactors, Part 2, Standard Review Plan and Acceptance Criteria, Chapter 16, Other License Considerations, is not necessary because:
- 1. All equipment to be installed in the Hermes 2 facility will be new and purpose-built. No prior use components will be used in the construction of the reactor or support systems.
- 2. The Hermes 2 facility will not contain equipment or facilities associated with the direct medical administration of radioisotopes or other radiation-based therapies.
- 3. There are no identified license considerations relevant to Hermes 2 that are not considered elsewhere in this SE.
16.1 References Kairos Power LLC. Submittal of the Construction Permit Application for the Hermes 2 Kairos Power Fluoride Salt-Cooled, High Temperature Non-Power Reactor, July 14, 2023, Pkg.
The U. S. Nuclear Regulatory Commission (NRC). NUREG-1537, Guidelines for Preparing and Reviewing Applications for the Licensing of Non-Power Reactors, Part 2, Standard Review Plan and Acceptance Criteria. NRC: Washington, D.C. February 1996. ML042430048.
THIS NRC STAFF DRAFT SE HAS BEEN PREPARED AND IS BEING RELEASED TO SUPPORT INTERACTIONS WITH THE ACRS. THIS DRAFT SE HAS NOT BEEN SUBJECT TO FULL NRC MANAGEMENT AND LEGAL REVIEWS AND APPROVALS, AND ITS CONTENTS SHOULD NOT BE INTERPRETED AS OFFICIAL AGENCY POSITIONS.
17 DECOMMISSIONING AND POSSESSION-ONLY LICENSE AMENDMENTS The Kairos Power LLC (Kairos) preliminary safety analysis report (PSAR), Revision 1, Chapter 17, Decommissioning and Possession Only License Amendments, Section 17.1, Decommissioning, states that a decommissioning report for the Hermes 2 facility will be provided with an operating license application, as required by Title 10 of the Code of Federal Regulations (10 CFR) Section 50.33, Contents of applications; general information, paragraph (k). Furthermore, Section 17.2, Possession-Only License Amendments, of the Hermes 2 PSAR states that possession-only licenses are not applicable to the construction and operation phases of the Hermes 2 facility. Kaiross construction permit application did not include a decommissioning report or plan, or a possession-only license amendment request.
The U.S. Nuclear Regulatory Commission (NRC) staff (the staff) notes that 10 CFR 50.33(k) requires an applicant for an operating license for a utilization facility to submit a decommissioning report but does not require an applicant for a construction permit for a utilization facility to submit a decommissioning report or plan. The guidance of NUREG1537, Guidelines for Preparing and Reviewing Applications for the Licensing of Non-Power Reactors, Part 2, Standard Review Plan and Acceptance Criteria, Chapter 17, Decommissioning and Possession-Only License Amendments, indicates that decommissioning plans and applications for possession-only licenses are submitted by nonpower reactor licensees who wish to terminate operations and decommission their facilities. The staff evaluated PSAR Chapter 17 considering these requirements and guidance. Because Kaiross application seeks a construction permit for a utilization facility, and because Kairos is not seeking a possession-only license, the staff concludes that no decommissioning information or possession-only license amendment request needs to be provided in the PSAR or evaluated by staff for the issuance of a construction permit for a utilization facility under 10 CFR Part 50, Domestic Licensing of Production and Utilization Facilities.
17.1 References Kairos Power LLC. Submittal of the Construction Permit Application for the Hermes 2 Kairos Power Fluoride Salt-Cooled, High Temperature Non-Power Reactor, July 14, 2023, Pkg.
The U. S. Nuclear Regulatory Commission (NRC). NUREG-1537, Guidelines for Preparing and Reviewing Applications for the Licensing of Non-Power Reactors, Part 2, Standard Review Plan and Acceptance Criteria. NRC: Washington, D.C. February 1996. ML042430048.
THIS NRC STAFF DRAFT SE HAS BEEN PREPARED AND IS BEING RELEASED TO SUPPORT INTERACTIONS WITH THE ACRS. THIS DRAFT SE HAS NOT BEEN SUBJECT TO FULL NRC MANAGEMENT AND LEGAL REVIEWS AND APPROVALS, AND ITS CONTENTS SHOULD NOT BE INTERPRETED AS OFFICIAL AGENCY POSITIONS.
18 HIGHLY ENRICHED TO LOW-ENRICHED URANIUM CONVERSION The Kairos Power LLC (Kairos) preliminary safety analysis report (PSAR), Revision 1, Chapter 18, Highly Enriched to Low Enriched Uranium Conversion, states that the Hermes 2 reactor fuel will be high-temperature graphite-matrix coated tristructural isotropic (TRISO) particles using high-assay, and low-enriched uranium (LEU). The Hermes 2 facility will not utilize highly enriched uranium (HEU), i.e., uranium that is enriched to 20 percent or more in uranium-235.
The U.S. Nuclear Regulatory Commission (NRC) staff (the staff) evaluated the information on the Hermes 2 facility in the PSAR and finds that the preliminary design of the Hermes facility does not utilize HEU. Therefore, the staff concludes that an evaluation of HEU to LEU conversion using the guidelines of NUREG1537, Guidelines for Preparing and Reviewing Applications for the Licensing of Non-Power Reactors, Part 2, Standard Review Plan and Acceptance Criteria, Chapter 18, Highly Enriched to Low-Enriched Uranium Conversions, is not necessary.
18.1 References Kairos Power LLC. Submittal of the Construction Permit Application for the Hermes 2 Kairos Power Fluoride Salt-Cooled, High Temperature Non-Power Reactor, July 14, 2023, Pkg.
The U. S. Nuclear Regulatory Commission (NRC). NUREG-1537, Guidelines for Preparing and Reviewing Applications for the Licensing of Non-Power Reactors, Part 2, Standard Review Plan and Acceptance Criteria. NRC: Washington, D.C. February 1996. ML042430048.
THIS NRC STAFF DRAFT SE HAS BEEN PREPARED AND IS BEING RELEASED TO SUPPORT INTERACTIONS WITH THE ACRS. THIS DRAFT SE HAS NOT BEEN SUBJECT TO FULL NRC MANAGEMENT AND LEGAL REVIEWS AND APPROVALS, AND ITS CONTENTS SHOULD NOT BE INTERPRETED AS OFFICIAL AGENCY POSITIONS.
6 ENGINEERED SAFETY FEATURES Engineered safety features (ESFs) are features designed to mitigate the consequences of accidents and to keep radiological exposures within acceptable values. For this reason, ESFs must be designed to function during a full range of conditions, from normal operation to accident conditions. The need for ESFs in a test reactor is design-specific and determined through an applicants accident analyses.
This chapter of the Kairos Power LLC (Kairos) Hermes 2 construction permit (CP) safety evaluation (SE) describes the U.S. Nuclear Regulatory Commission (NRC) staffs (the staffs) technical review and evaluation of the preliminary information provided in Chapter 6, Engineered Safety Features, of the Hermes 2 preliminary safety analysis report (PSAR),
Revision 1. The staff reviewed Chapter 6 of the Hermes 2 PSAR against applicable regulatory requirements using regulatory guidance and standards to assess the sufficiency of the preliminary information on the Hermes 2 ESFs for the issuance of CPs in accordance with Title 10 of the Code of Federal Regulations (10 CFR) Part 50, Domestic Licensing of Production and Utilization Facilities. As part of this review, the staff evaluated information on the Hermes 2 ESFs, with special attention given to design and operating characteristics, unusual or novel design features, and principal safety considerations. The staff evaluated the preliminary design of the Hermes 2 ESFs to ensure the design criteria, design bases, and information relative to construction is sufficient to provide reasonable assurance that the final design will conform to the design basis. In addition, the staff reviewed Kaiross identification and justification for the selection of those variables, conditions, or other items which are determined to be probable subjects of technical specifications (TS) for the facility, with special attention given to those items which may significantly influence the final design.
In its review of areas relevant to PSAR Chapter 6, the staff considered the information in technical report KP-TR-017, KP-FHR Core Design and Analysis Methodology, Revision 1, dated September 29, 2022, and technical report KP-TR-022, Hermes 2 Postulated Event Analysis Methodology, Revision 0, dated June 30, 2023. These technical reports were submitted as part of the Hermes 2 CP application and are referenced in the Hermes 2 PSAR.
The staffs reviews and evaluations for areas relevant to PSAR Chapter 6, including regulations and guidance used, a summary of the application information reviewed, and evaluation findings and conclusions, are discussed in the SE sections below for each specific review area. A summary and overall conclusions on the staffs technical evaluation of the Hermes 2 ESFs are provided in SE Section 6.4, Summary and Conclusions on Engineered Safety Features.
6.1 Summary Description PSAR Section 6.1, Summary Description, provides a high-level overview of the Hermes 2 ESFs. The ESFs for each of the Hermes 2 non-power test reactor units consist of the functional containment and the decay heat removal system (DHRS), both of which are credited in PSAR Chapter 13, Accident Analysis. The functional containment includes the tristructural isotropic (TRISO) fuel particles and the Flibe coolant. The fuel design is the primary means of containing radionuclides for the Hermes 2 reactor units. Each units DHRS removes heat from the reactor vessel (RV) to ensure RV and fuel integrity when the normal heat rejection system is not available.
THIS NRC STAFF DRAFT SE HAS BEEN PREPARED AND IS BEING RELEASED TO SUPPORT INTERACTIONS WITH THE ACRS. THIS DRAFT SE HAS NOT BEEN SUBJECT TO FULL NRC MANAGEMENT AND LEGAL REVIEWS AND APPROVALS, AND ITS CONTENTS SHOULD NOT BE INTERPRETED AS OFFICIAL AGENCY POSITIONS.
NUREG1537, Guidelines for Preparing and Reviewing Applications for the Licensing of Non-Power Reactors, Part 1, Format and Content, and Part 2, Standard Review Plan and Acceptance Criteria, Section 6.1, Summary Description, do not stipulate any specific review findings for this section; therefore, the staff did not make any findings relative to Hermes 2 PSAR Section 6.1. PSAR Sections 6.2, Functional Containment, and 6.3, Decay Heat Removal System, provide detailed descriptions of the functional containment and DHRS, respectively. The corresponding sections of this SE document the staffs review findings on these ESFs.
6.1.1 Common Regulatory Evaluation for Engineered Safety Features The staff reviewed Section 6.1.1, Common Regulatory Evaluation for Engineered Safety Features, of the Hermes 1 SE for applicability to the Hermes 2 SE. Based on the similarities between the Hermes 1 and Hermes 2 facility designs and the consistency of the ESF designs between Hermes 1 and Hermes 2, the staff finds that the regulations and guidance listed in Section 6.1.1 of the Hermes 1 SE are applicable to Hermes 2. Therefore, this section incorporates by reference Section 6.1.1 of the Hermes 1 SE.
6.2 Functional Containment 6.2.1 Introduction Section 6.2, Functional Containment, of the Hermes 2 PSAR describes the approach of using a functional containment consisting of physical barriers, operating conditions, coolant design, and fuel form to limit the potential release of radioactive material instead of a traditional containment. The TRISO fuel particles retain most of the radioactive material at risk for release and the Flibe coolant in which the fuel pebbles are submerged is also credited for retaining radionuclides that are not aerosolized or evaporated during an event. In addition, the near-atmospheric primary system pressure precludes the type of high-energy releases associated with highly pressurized primary systems.
The individual components of the functional containment are described in PSAR Chapter 4, Reactor Description, and PSAR Chapter 5, Heat Transport System. PSAR Chapter 13 describes accident analyses using the integral functional containment approach. In addition, PSAR Chapter 14, Technical Specifications, discusses variables and conditions that are probable subjects of TSs associated with the fuel, coolant, and reactor.
6.2.2 Regulatory Evaluation The staff reviewed Section 6.2.2, Regulatory Evaluation, of the Hermes 1 SE for applicability to the Hermes 2 SE. Based on the similarities between the Hermes 1 and Hermes 2 facility designs and the consistency of the functional containment approach between Hermes 1 and Hermes 2, the staff finds that the regulations and guidance listed in Section 6.2.2 of the Hermes 1 SE are applicable to Hermes 2. Therefore, this section incorporates by reference Section 6.2.2 of the Hermes 1 SE.
6.2.3 Technical Evaluation The staff reviewed Section 6.2 of the Hermes 2 PSAR and compared it to the equivalent section in the Hermes 1 PSAR (Section 6.2, Functional Containment). The staff found that Section 6.2 of the Hermes 2 PSAR contains information consistent with that in the Hermes 1 PSAR. The
staff also verified that the Hermes 2 functional containment approach remains identical to Hermes 1. Based on these consistencies, this section incorporates by reference Section 6.2.3 of the Hermes 1 SE.
On the basis of its review, the staff finds that the level of detail provided regarding the design of the Hermes 2 functional containment demonstrates an adequate basis for a preliminary design and satisfies the applicable acceptance criteria of NUREG-1537, Part 2, Sections 6.2.1 and 6.2.2, to limit the potential release of radioactive material to the environment.
6.2.4 Conclusion Based on the staff findings above, and as incorporated by reference from the Hermes 1 SE, the staff concludes the information in Hermes 2 PSAR Section 6.2 is sufficient, is consistent with the applicable guidance, and meets the regulatory requirements identified in this section for the issuance of CPs in accordance with 10 CFR 50.35 and 10 CFR 50.40. In addition, the staff concludes that the preliminary information on the functional containment approach is consistent with the approach described in SECY-18-0096, Functional Containment Performance Criteria for Non-Light-Water Reactors, and the Staff Requirements Memorandum for SECY180096.
Further information as may be required to complete the review of the Hermes 2 functional containment (e.g., final safety analyses) can reasonably be left for later consideration at the OL stage since this information is not necessary to be provided as part of a CP application.
6.3 Decay Heat Removal System 6.3.1 Introduction Section 6.3, Decay Heat Removal System, of the Hermes 2 PSAR describes the DHRS, which is an exvessel system that removes decay heat from each reactor core during normal and off-normal conditions. Its safety function is to remove decay heat during and after postulated events, including the maximum hypothetical accident, that assume unavailability of the normal heat rejection system. There is one DHRS per unit and the DHRS does not share SSCs between the units. The DHRS includes four independent trains comprised of annular thermosyphon thimbles, steam separators, and water storage tanks. Heat is transferred from the reactor vessel to the water-based thermosyphons through thermal radiation and convection.
Water in the thermosyphons, supplied by the water storage tanks, boils off and vents to the atmosphere.
6.3.2 Regulatory Evaluation The staff reviewed Section 6.3.2, Regulatory Evaluation, of the Hermes 1 SE for applicability to the Hermes 2 SE. Based on the similarities between the Hermes 1 and Hermes 2 facility designs and the consistency of the DHRS design between Hermes 1 and Hermes 2, the staff finds that the regulations and guidance listed in Section 6.3.2 of the Hermes 1 SE are applicable to Hermes 2. Therefore, this section incorporates by reference Section 6.3.2 of the Hermes 1 SE.
6.3.3 Technical Evaluation The staff reviewed Section 6.3 of the Hermes 2 PSAR and compared it to the equivalent section in the Hermes 1 PSAR (Section 6.3, Decay Heat Removal System). The staff found that Section 6.3 of the Hermes 2 PSAR contains information consistent with that in the Hermes 1
PSAR, except for a minor change, which is evaluated below. The staff also verified that the Hermes 2 DHRS design and functionality remain identical to Hermes 1. Based on these consistencies, this section incorporates by reference Section 6.3.3 of the Hermes 1 SE.
6.3.3.1 Minor Change Compared to the Hermes 1 PSAR The minor change in Hermes 2 PSAR Section 6.3, as compared to the information in Hermes 1 PSAR Section 6.3, includes the following:
PSAR Section 6.1, Summary Description, clarifies that for the Hermes 2 design, there is one DHRS per unit, and the DHRS does not share components between units. The design information in PSAR Section 6.3 applies to both units.
The staff determined that the Hermes 2 DHRS design did not change relative to the Hermes 1 DHRS design. The only difference related to the DHRS is that the Hermes 2 facility includes two reactor units instead of one and each unit has its own DHRS. Because there is no impact to DHRS design or functionality, the staff finds that having a separate DHRS for each unit is acceptable.
On the basis of its review, the staff finds that the level of detail provided regarding the Hermes 2 DHRS designs demonstrates an adequate basis for a preliminary design and satisfies the applicable acceptance criteria of NUREG-1537, Part 2, Sections 5.3 and 6.2.3, and applicable principal design criteria (PDC) discussed in Section 6.3.3 of the Hermes 1 SE to support the DHRS safety function of passive residual heat removal, in accordance with 10 CFR 50.34(a)(3).
6.3.4 Conclusion Based on the staff findings above, and as incorporated by reference from the Hermes 1 SE, the staff concludes the information in Hermes 2 PSAR Section 6.3 is sufficient and meets the applicable guidance and regulatory requirements identified in this section for the issuance of CPs in accordance with 10 CFR 50.35 and 10 CFR 50.40. Further information as may be required to complete the review of the Hermes 2 DHRSs can reasonably be left for later consideration at the OL stage since this information is not necessary for the review of a CP application.
6.4 Summary and Conclusions on the Engineered Safety Features The staff evaluated the information on the Hermes 2 ESFs as described in PSAR Chapter 6 and finds that the preliminary information on, and design criteria of, the ESFs, including the PDC, design bases, and information relating to materials of construction, general arrangement, and approximate dimensions: (1) provide reasonable assurance that the final design will conform to the design bases, (2) meet all applicable regulatory requirements, and (3) meet the applicable acceptance criteria in NUREG1537, Part 2. Based on these findings, the staff makes the following conclusions regarding issuance of CPs in accordance with 10 CFR 50.35 and 10 CFR 50.40:
Kairos has described the proposed design of the ESFs, including, but not limited to, the principal engineering criteria for the design, and has identified the major features or components incorporated therein for the protection of the health and safety of the public.
Such further technical or design information as may be required to complete the safety analysis of the ESFs, and which can reasonably be left for later consideration, will be provided in the final safety analysis report as part of the OL application.
There is reasonable assurance: (i) that the construction of the Hermes 2 facility will not endanger the health and safety of the public, and (ii) that construction activities can be conducted in compliance with the Commissions regulations.
The issuance of permits for the construction of the Hermes 2 facility would not be inimical to the common defense and security or to the health and safety of the public.
6.5 References American Concrete Institute (ACI). ACI 34913. Code Requirements for Nuclear Safety-Related Concrete Structures and Commentary. 2014.
American Society of Mechanical Engineers (ASME). Boiler and Pressure Vessel Code,Section III, Division 5. High Temperature Reactors. ASME: New York, NY. 2017.
American Society of Civil Engineers (ASCE). ASCE 4-16. Seismic Analysis of Safety-Related Nuclear Structures. ASCE: Reston, VA. 2017.
American Society of Civil Engineers/Structural Engineering Institute (ASCE/SEI). ASCE/SEI 43-
- 19. Seismic Design Criteria for Structures, Systems, and Components in Nuclear Facilities.
Electric Power Research Institute (EPRI). Uranium Oxycarbide (UCO) Tristructural (TRISO)-
Coated Particle Fuel Performance. Topical Report EPRI-AR-1(NP)-A. EPRI Report
- 3002019978. 2020. ML20336A052.
Kairos Power LLC. KPTR003NPA, "Principal Design Criteria for the Kairos Power Fluoride Salt-Cooled, High Temperature Reactor," Revision 1, June 2020, ML20167A174.
. KP-FHR Fuel Performance Methodology. KP-TR-010-NP-A, Revision 3. May 2022.
ML22125A278 (redacted version).
. Fuel Qualification Methodology for the Kairos Power Fluoride Salt-Cooled High Temperature Reactor (KP-FHR). KP-TR-011-NP, Revision 2. June 2022. ML22186A215 (redacted version).
. Submittal of the Preliminary Safety Analysis Report for the Kairos Power Fluoride Salt-Cooled, High Temperature Non-Power Reactor (Hermes), Revision 1, September 29, 2022, Pkg. ML22272A593. (Includes KP-TR-017, KP-FRN Core Design and Analysis Methodology, Revision 1 (redacted version), as Enclosure 4.)
. Metallic Materials Qualification for the Kairos Power Fluoride SaltCooled High Temperature Reactor. KPTR013NP, Revision 4. September 2022. ML22263A456. (redacted version).
. Graphite Material Qualification for the Kairos Power Fluoride SaltCooled High Temperature Reactor. KPTR014NP, Revision 4. September 2022. ML22259A142 (redacted version).
. Transmittal of Response to NRC Question on DHRS Testing from PSAR Section 6.3 Audit on Hermes Preliminary Safety Analysis Report. KP-NRC-2209-003. September 2022.
ML22244A235 (redacted version).
. Transmittal of Changes to Preliminary Safety Analysis Report Chapter 6 and Response to NRC Question on DHRS Testing. KP-NRC-2212-003. December 2022. ML22353A625.
. Submittal of the Preliminary Safety Analysis Report for the Kairos Power Fluoride Salt-Cooled, High Temperature Non-Power Reactor (Hermes), Revision 2, February 24, 2023, Pkg.
ML23055A672. (Includes KP-TR-018, Postulated Event Analysis Methodology, Revision 2 (redacted version), as Enclosure 3.)
. Submittal of the Preliminary Safety Analysis Report for the Kairos Power Fluoride Salt-Cooled, High Temperature Non-Power Reactor (Hermes), Revision 3, May 31, 2023, Pkg.
. Submittal of the Construction Permit Application for the Hermes 2 Kairos Power Fluoride Salt-Cooled, High Temperature Non-Power Reactor, Revision 1, [month] xx, 2024, Pkg.
MLxxxxxxxxx.
Nuclear Regulatory Commission (U.S.) (NRC). NUREG1537, Guidelines for Preparing and Reviewing Applications for the Licensing of Non-Power Reactors, Part 1, Format and Content, and Part 2, Standard Review Plan and Acceptance Criteria. NRC: Washington, D.C. February 1996. ADAMS Accession Nos. ML042430055 and ML042430048.
. SECY-18-0096, Functional Containment Performance Criteria for Non-Light-Water-Reactors. NRC: Washington, D.C. September 2018. ML18114A546.
. SRM-SECY-18-0096, Staff Requirements - SECY-18-0096 - Functional Containment Performance Criteria for Non-Light-Water-Reactors. NRC: Washington, D.C. December 2018.
. Regulatory Guide (RG) 1.87, Revision 2, Acceptability of ASME Code Section III, Division 5, High Temperature Reactors. NRC: Washington, D.C. January 2023. ML22101A263.
. Summary Report for the Regulatory Audit of Kairos Power LLC Hermes Construction Permit Preliminary Safety Analysis Report Decay Heat Removal System (Chapter 6, Section 6.3), April 2023, ML23115A480.
. Safety Evaluation Related to the Kairo Power LLC Construction Permit Application for the Hermes Test Reactor, Docket 50-7513, June 13, 2023. ML23158A265.
8 ELECTRICAL POWER SYSTEMS This chapter of the Hermes 2 construction permit safety evaluation (SE) describes the technical review and evaluation by the U.S. Nuclear Regulatory Commission (NRC) staff (the staff) of the preliminary design of the Kairos Power LLC (Kairos) Hermes 2 Test Reactor facility as presented in Chapter 8, Electric Power Systems, of the Hermes 2 preliminary safety analysis report (PSAR), Revision 1. The staff reviewed Hermes 2 PSAR Chapter 8 against applicable regulatory requirements using regulatory guidance and standards to assess the sufficiency of the preliminary design of the Hermes 2 facility. The following sections of the SE describe the areas reviewed as specified in NUREG1537, Guidelines for Preparing and Reviewing Applications for the Licensing of Non-Power Reactors, Part 2, Standard Review Plan and Acceptance Criteria.
8.1 Electrical Systems Hermes 2 PSAR Section 8.1, Summary Description, states that the purpose of the electrical system is to provide power to plant equipment for operation and that the electrical system consists of the non-Class 1E normal power system and the backup power system (BPS).
Further, Kairos states that, due to the passive design of Hermes 2, safety related structures, systems, and components (SSCs) do not require electric power to perform safety related functions following a design basis event. The design has no emergency electrical power systems, as described in NUREG1537, Part 2, Section 8.2, Emergency Electrical Power Systems. In addition, Kairos states that alternating current (AC) and direct current (DC) power from offsite or backup power sources is not required to mitigate a design basis event.
8.2 Normal Power System 8.2.1 Introduction Hermes 2 PSAR Section 8.2, Normal Power System, states that the normal power system is supplied by an offsite power source from the local utility, which provides a medium voltage feeder, or by the onsite turbine generator system via a 13.8 kilovolt (kV) feeder and associated 13.8 kV / 4.16 kV step down transformer. Voltage is stepped down further with 4.16 kV / 480 volt (V) transformers to support power distribution to plant loads at both units with 480 V and 120 V buses. A loss of voltage or a degraded voltage condition on the normal power system does not adversely affect the performance of safety related functions.
8.2.2 Regulatory Evaluation The applicable regulatory requirements for the evaluation of Hermes 2 normal power systems are as follows:
Title 10 of the Code of Federal Regulations (10 CFR) Section 50.34, Contents of applications; technical information, including:
o 10 CFR 50.34(a)(3)(ii) which requires The design bases and the relation of the design bases to the principal design criteria.
o 10 CFR 50.34(a)(3)(iii) which requires Information relative to materials of construction, general arrangement, and approximate dimensions, sufficient to provide reasonable assurance that the final design will conform to the design bases with adequate margin for safety.
THIS NRC STAFF DRAFT SE HAS BEEN PREPARED AND IS BEING RELEASED TO SUPPORT INTERACTIONS WITH THE ACRS. THIS DRAFT SE HAS NOT BEEN SUBJECT TO FULL NRC MANAGEMENT AND LEGAL REVIEWS AND APPROVALS, AND ITS CONTENTS SHOULD NOT BE INTERPRETED AS OFFICIAL AGENCY POSITIONS.
o 10 CFR 50.34(a)(4), which requires [a] preliminary analysis and evaluation of the design and performance of structures, systems, and components [SSCs] of the facility; and 10 CFR 50.35, Issuance of construction permits.
10 CFR 50.40, Common standards.
The applicable guidance for the evaluation of the Hermes 2 normal power systems is as follows:
NUREG1537, Guidelines for Preparing and Reviewing Applications for the Licensing of Non-Power Reactors, Part 1, Format and Content, and Part 2, Standard Review Plan and Acceptance Criteria, Section 8.1, Normal Electrical Power Systems.
8.2.3 Technical Evaluation The Principal Design Criteria (PDC) for the facility SSCs are described in Hermes 2 PSAR Section 3.1 and are based on those specified in the NRC-approved Kairos Power Topical Report, KPTR003NP-A, Principal Design Criteria for the Kairos Power Fluoride Salt-Cooled, High Temperature Reactor. Hermes 2 PSAR, Section 3.1, Table 3.13, Principal Design Criteria, identifies PDCs 2, 17, and 18 as applicable to Chapter 8.
The normal power system is designed in accordance with National Fire Protection Association (NFPA) 70, National Electrical Code 2020, and Institute of Electrical and Electronics Engineers (IEEE), IEEE-C2, National Electrical Safety Code (NESC) 2023, as stated in PSAR Section 8.2.3, System Evaluation.
In Hermes 2 PSAR Section 8.2.1.1, AC Electrical Power, Kairos states that AC electrical power components include the following:
A 4.16 kV / 480 V step down transformer connected to a single 4.16 kV offsite electrical power supply from the local utility, Incoming 13.8 kV feeder from the turbine generator system and associated 13.8 kV /
4.16 kV step down transformer, The low voltage AC electrical power distribution with nominal bus voltages of 480 V and 120 V, and A 13.8 kV / 161kV transformer from the turbine generator system to the onsite electrical switchyard.
Further, Kairos stated that selected loads are supplied with continual AC power via uninterruptible power supplies (UPS), which provide power during normal operations and backup power during a loss of normal electrical power.
In PSAR Section 8.2.1.2, DC Electrical Power, Kairos states that 125 volts direct current (VDC) is provided to switchgear control power and 24 VDC is provided to instrumentation and control (I&C) functions during normal operations and for a specified maximum duty cycle following a loss of AC power. Kairos further states that DC electrical power is not shared between Unit 1 and Unit 2.
In PSAR Section 8.2.2, Design Bases, Kairos states that the normal power system does not perform any safety related functions, is not credited for the mitigation of postulated events, and
is not credited with performing safe shutdown functions. Further, Kairos states in PSAR Section 8.2.3, System Evaluation, states that malfunction of the normal power system will not cause reactor damage or prevent safe reactor shutdown. Section 8.2.3 also states that adequate independence is maintained between the non-safety normal power system and Class 1E I&C system. Therefore, Section 8.2 discusses the design bases and provides a function description of the normal power systems consistent with the guidance in NUREG-1537, Part 2, Section 8.1. The Hermes 2 I&C systems are evaluated in Chapter 7 of this SE. In the staffs review of PSAR Chapter 8 and, particularly, Figure 8.11, Electrical Configuration Diagram, the staff identified a dedicated connection from the local utility to the normal power system.
The staff reviewed the PDCs listed in PSAR Chapter 8 against the Hermes 2 design. PDC 17, Electric power systems, states that electric power systems shall be provided when required to permit functioning of SSCs. PDC 18, Inspection and testing of electric power systems, states that electric power systems which are safety related shall be designed to permit appropriate inspection and testing. The staffs review found that there are no Class 1E electric power systems based on the PSAR statements that the normal power system is not credited for accident mitigation or safe shutdown; that the normal power system is classified as non-Class 1E or non-safety; and that no technical specifications for the normal power system are required.
Based on these aspects of the design, the staff finds that PDCs 17 and 18 are not applicable to the Hermes 2 facility.
Additionally, PSAR Section 8.2.3, System Evaluation states that grounding and lightning protection will be implemented, and the switchyard protection scheme follows the design approach for protective devices, feeders, branch circuits, and transformers in accordance with IEEE Standard 242-2001, IEEE Recommended Practice for Protection and Coordination of Industrial and Commercial Power Systems (IEEE Buff Book). Kairos further states that these features demonstrate conformance with PDC 2, Design bases for protection against natural phenomena. The staff views grounding and lightning protection and switchyard protection to be a good engineering practice; however, PDC 2, as discussed in the TR KP-TR-003-NP-A, Principal Design Criteria for the Kairos Power Fluoride Salt-Cooled, High Temperature Reactor, applies to SSCs which are safety significant. Hermes 2 PSAR Section 3.1.1, Design Criteria, clarifies that the term safety significant is replaced with safety-related for PDC 2 and other PDCs. For the Hermes 2 design, the normal power system is not safety-related; therefore, the staff finds that PDC 2 is not applicable to the Hermes 2 normal power systems design.
The staff finds that the level of detail provided in the PSAR for the normal power system meets the applicable criteria of NUREG1537, Part 2, Section 8.1, and demonstrates an adequate design basis for a preliminary design, irrespective of the applicability of PDCs 2, 17, and 18 to the normal power systems. Because AC power from offsite sources will not be required to perform safe shutdown functions, the reactor can be safely shut down in the event of a loss or interruption of the normal electrical power system.
8.2.4 Conclusion Based on its review, the staff finds that the design of the Hermes 2 normal power system, as described in Hermes 2 PSAR Section 8.2, is sufficient and meets the applicable regulatory requirements and guidance identified in this section for the issuance of construction permits in accordance with 10 CFR 50.35 and 10 CFR 50.40. The staff also finds that PDCs 2, 17, and 18 are not applicable since there are no safety-related electrical power systems. A more detailed evaluation of the normal power system will occur during the review of the Hermes 2 operating
license (OL) application, at which time the staff will confirm that the final design conforms to this design basis.
8.3 Backup Power System 8.3.1 Introduction While there are no emergency electrical power systems in the Hermes 2 facility, Hermes 2 PSAR Section 8.3, Backup Power System, states that the BPSs design function is to provide AC electrical power to the essential facility loads when the normal AC power supply is not available. The BPS includes two backup generators, which are shared between the two units; three UPS per unit; two shared UPS; as well as electrical equipment and circuits used to interconnect the backup generators to the low voltage AC electrical power distribution systems.
The PSAR further states that the facility is equipped with a plug-in connection for use with a portable 480 V generator to provide power to essential loads in the event the backup generators are unavailable.
8.3.2 Regulatory Evaluation The applicable regulatory requirements for the evaluation of Hermes 2 BPSs are as follows:
10 CFR 50.34, including:
o 10 CFR 50.34(a)(3)(ii) which requires The design bases and the relation of the design bases to the principal design criteria.
o 10 CFR 50.34(a)(3)(iii) which requires Information relative to materials of construction, general arrangement, and approximate dimensions, sufficient to provide reasonable assurance that the final design will conform to the design bases with adequate margin for safety.
o 10 CFR 50.34(a)(4), which requires [a] preliminary analysis and evaluation of the design and performance of structures, systems, and components [SSCs] of the facility; and 10 CFR 50.35, Issuance of construction permits.
10 CFR 50.40, Common standards.
The applicable guidance for the evaluation of the Hermes 2 BPSs is as follows:
NUREG1537, Guidelines for Preparing and Reviewing Applications for the Licensing of Non-Power Reactors, Part 1, Format and Content, and Part 2, Standard Review Plan and Acceptance Criteria, Section 8.1, Normal Electrical Power Systems.
The staff notes that NUREG-1537 contains guidance for emergency electrical power systems in Parts 1 and 2, Section 8.2, Emergency Electrical Power Systems. However, because Kaiross BPSs are not emergency power systems and do not perform any safety related functions, but rather provides a backup to normal electric power for selected loads, as discussed below, the staff determined that NUREG-1537, Parts 1 and 2, Section 8.1, Normal Electrical Power Systems, is the applicable guidance for the staffs review of Hermes 2 BPSs.
8.3.3 Technical Evaluation The PDC for the facility SSCs are described in PSAR Section 3.1 and are based on those specified in the NRC-approved Kairos Power Topical Report, KPTR003NP-A. Hermes 2 PSAR Table 3.12, Principal Design Criteria, identifies the PDCs 2, 17, and 18 as applicable to electrical power systems.
PSAR Section 8.3.1.1, Backup generators, states that the backup generators are shared between the two units and automatically start in the event of a loss of offsite power to provide power to essential facility loads. Further, Kairos states that the backup generators are sized to simultaneously supply essential loads on both units. In addition, PSAR Section 8.3.1.2, Uninterruptible Power Supplies, states that selected unit-specific loads are supplied with AC power via UPS and the UPS provides backup power during a loss of normal electrical power.
Kairos further stated that the UPS are generally not shared between Unit 1 and Unit 2 unless the essential load is common to both units. Figure 8.1-1 indicates there are three UPS per unit and two additional that are shared between the units for emergency lighting and communications and for main control room power supplies.
Kairos stated in PSAR Section 8.3.2, Design Bases, that the BPS does not perform any safety related functions, is not credited for the mitigation of postulated events, and is not credited with performing safe shutdown functions. The BPS, as stated in PSAR Section 8.3.3, System Evaluation, is designed according to NFPA 70, National Electric Code 2020, so that postulated failures of SSCs in the system do not preclude a safety related SSC from performing its safety function. In the PSAR, Kairos addressed the classification and design attributes of the BPS, and the staff finds that PDCs 2, 17, and 18 are not applicable to the BPS since there are no safety-related electric power systems. Therefore, the PSAR discusses the design bases and provides a function description of the BPS consistent with the guidance in NUREG-1537, Part 2, Section 8.1.
The staff finds that the level of detail provided in the PSAR for the BPS satisfies the applicable acceptance criteria of NUREG1537, Part 2, Section 8.1, and demonstrates an adequate design basis for a preliminary design.
8.3.4 Conclusion Based on the staff findings above, the staff concludes that the description of the Hermes 2 BPS, as described in Hermes 2 PSAR Section 8.3, is sufficient and meets the applicable regulatory requirements and guidance identified in this section for the issuance of construction permits in accordance with 10 CFR 50.35 and 10 CFR 50.40. The staff also finds that PDCs 2, 17, and 18 are not applicable since there are no safety-related electrical power systems. A more detailed evaluation of the BPS will occur during the review of the Hermes 2 OL application, at which time the staff will confirm that the final design conforms to this design basis.
8.4 Summary and Conclusions on Electrical Power Systems The staff evaluated the information on the Hermes 2 electrical power systems as described in PSAR Chapter 8 and finds that the preliminary information on, and design criteria of, the electrical power systems, including the PDC, design bases, and other design information: (1) provide reasonable assurance that the final design will conform to the design bases, (2) meet all applicable regulatory requirements, and (3) meet the applicable acceptance criteria in
NUREG1537, Part 2. Based on these findings, the staff concludes the following regarding issuance of construction permits in accordance with 10 CFR 50.35 and 10 CFR 50.40:
Kairos has described the proposed design for the electrical power systems, including, but not limited to, the principal engineering criteria for the design, and has identified the major features or components incorporated therein for the protection of the health and safety of the public.
Such further technical or design information as may be required to complete the safety analysis of the electrical power systems, and which can reasonably be left for later consideration, will be provided in the operating license application.
There is reasonable assurance: (i) that the construction of the facility will not endanger the health and safety of the public, and (ii) that construction activities will be conducted in compliance with the Commissions regulations.
The issuance of permits for the construction of the Hermes 2 facility would not be inimical to the common defense and security or to the health and safety of the public.
8.5 References Kairos Power LLC. KPTR003NPA, "Principal Design Criteria for the Kairos Power Fluoride Salt-Cooled, High Temperature Reactor," Revision 1, June 2020, ML20167A174.
. Submittal of the Preliminary Safety Analysis Report for the Kairos Power Fluoride Salt-Cooled, High Temperature Non-Power Reactor (Hermes), Revision 1, Pkg. MLxxxxxxxxx.
National Fire Protection Association (NFPA) 70, National Electrical Code 2020.
Nuclear Regulatory Commission (U.S.) (NRC). NUREG-1537, Part 2, "Guidelines for Preparing and Reviewing Applications for the Licensing of Non-Power Reactors Standard Review Plan and Acceptance Criteria." NRC: Washington, D.C. February 1996. ML042430048.
Institute of Electrical and Electronics Engineers, IEEE-C2, National Electrical Safety Code (NESC) 2023.
IEEE Standard 242-2001, IEEE Recommended Practice for Protection and Coordination of Industrial and Commercial Power Systems (IEEE Buff Book).