ML25105A044
| ML25105A044 | |
| Person / Time | |
|---|---|
| Site: | 99902069 |
| Issue date: | 05/14/2025 |
| From: | Cayetano Santos NRC/NRR/DANU/UAL1 |
| To: | Joshua Borromeo NRC/NRR/DANU/UAL1 |
| References | |
| Download: ML25105A044 (1) | |
Text
May 14, 2025 MEMORANDUM TO:
Josh Borromeo, Chief Advanced Reactor Licensing Branch 1 Division of Advanced Reactors and Non-Power Production and Utilization Facilities Office of Nuclear Reactor Regulation FROM:
Cayetano Santos Jr., Senior Project Manager Advanced Reactor Licensing Branch 1 Division of Advanced Reactors and Non-Power Production and Utilization Facilities Office of Nuclear Reactor Regulation
SUBJECT:
SUMMARY
OF APRIL 28, 2025, MEETING WITH KAIROS ON THE PROPOSED TOPICAL REPORT, OPERATOR TRAINING AND TESTING PROGRAM FOR THE KAIROS POWER FLUORIDE SALT-COOLED HIGH-TEMPERATURE TEST REACTORS, AND THE ASSOCIATED EXEMPTION Meeting Information:
Applicant: Kairos Power, LLC (Kairos)
Project No.: 99902069 Meeting Type: Virtual Observation Meeting Public Meeting Notice: Agencywide Documents Access and Management System (ADAMS)
Accession No.: ML25059A252 Applicant Presentation Slides: ML25108A137
Contact:
Cayetano Santos, NRR/DANU (301) 415-7270 CAYETA NO SANTOS Digitally signed by CAYETANO SANTOS Date:
2025.05.14 16:14:20 -04'00'
J. Borromeo 2
Meeting Summary:
On September 27, and December 4, 2024, observation public meetings were held between the U.S. Nuclear Regulatory Commission (NRC) staff and representatives of Kairos Power, LLC (Kairos) to discuss NRC staff feedback on the forthcoming topical report (TR), Operator Training and Testing Program for the Kairos Power Fluoride Salt-Cooled High-Temperature Test Reactors, and the exemption that will be necessary to implement the approach detailed in the TR. The summaries for the September 27 and December 4, 2024, meetings can be found at ML24282A673 and ML25006A023, respectively.
These discussions continued during another observation public meeting on April 28, 2025.
Below is a summary of the comments and discussions:
Kairos staff clarified that the TR is not requesting approval of a simulation facility. The TR would be used as the basis for a future request for approval of a simulation facility.
The NRC staff noted that Slide 9 of the presentation says, Performance testing descriptions provided in accordance with 10 CFR 55.46(b)(ii), except for the final testing results that would be provided at the time of the simulation facility inspection. Title 10 of the Code of Federal Regulations (10 CFR) 55.46(b)(ii) states the request for Commission approval of a simulation facility must include not only the description of performance tests for the simulation facility, but also the results of these tests. Before accepting the TR for formal review, the NRC staff would want to understand when the results of the final performance tests would be submitted (i.e., docketed), and that the information would be provided in time for the NRC staff to complete the review of a future request for a Commission approved simulator on the established schedule. The NRC staff also explained that an inspection is not required as part of the review of a request for Commission approval of a simulation facility. Rather, information would need to be docketed to address the results of the performance tests, and the NRC staff may perform an audit, if necessary. Kairos staff will consider updating to the TR to discuss when the results of performance tests could be available.
The NRC staff noted that linked licensing actions in which approval of one licensing action is contingent upon approval of another licensing action could add complexity to the formal acceptance of the licensing action that is contingent upon the other.
The NRC staff stated that if Kairos plans to use the plant for the operating test, it appears that a request for Commission approval per 10 CFR 55.46(b) is needed. Kairos staff stated that it does not intend to use the main control room for operating tests.
The NRC staff noted that in the draft topical report, Kairos states that the reactivity control manipulations that operator applicants must perform to receive a license will either use an approved simulation facility (i.e., part-task simulator) or the reactor facility (i.e., the plant). For the part-task simulator to be used for the reactivity manipulations required for the initial license applications prior to initial fuel load, Kairos would need to also request an exemption from the requirement in 10 CFR 55.31(a)(5), which states, in part, Provide evidence that the applicant, as a trainee, has successfully manipulated the controls of either the facility for which a license is sought or a plant-referenced simulator that meets the requirements of § 55.46(c). The request would be to use the Kairos
J. Borromeo 3
Commission-approved simulator instead of the plant or a plant-referenced simulator for the reactivity control manipulations.
The NRC staff observed that, based on the information presented in the draft topical report, it was not clear why the Kairos simulator would not meet the definition in 10 CFR 55.4 for a plant-referenced simulator. The NRC staff and Kairos staff discussed that at some point, the simulator would model the systems of the reference plant with which the operators would interface in the plants control room. The Kairos simulator also appears to potentially meet requirements in 10 CFR 55.46(c)(1)(i). However, the Kairos simulator does not appear to meet 10 CFR 55.46(c)(1)(ii), which states, in part, The plant-referenced simulator must be designed and implemented so that it: (ii) Allows for the completion of control manipulations for operator license applicants, because, per 10 CFR 55.46(c)(2), Facility licensees that propose to use a plant-referenced simulator to meet the control manipulation requirements in § 55.31(a)(5) must ensure that: (i) The plant-referenced simulator utilizes models relating to nuclear and thermal-hydraulic characteristics that replicate the most recent core load in the nuclear power reference plant for which a license is being sought If the Kairos simulator meets all the criteria to be considered a plant-referenced simulator with the exception of 55.46(c)(2)(i), Kairos could request an exemption from 10 CFR 55.46(c)(2)(i) since it is not possible to replicate the most recent core load until after the core has been loaded. If an exemption to 10 CFR 55.46(c)(2)(i) were granted, then the criterion in 10 CFR 55.46(c)(1)(ii) would be met. Establishing a plant-referenced simulator could be an alternative to requesting Commission approval of the simulation facility.
The NRC staff noted that it is possible to have a plant-referenced simulator before construction of a plant is complete.
The NRC staff stated that the use of a Commission approved simulator requires a licensee to submit a formal request to the NRC. However, the use of a plant-referenced simulator does not require Commission approval. The licensee notifies the NRC when a plant-referenced simulator has been established, and the NRC staff would perform an inspection per NRC inspection procedure 41502, Nuclear Power Plant Simulation Facilities (ML12233A564).
The NRC staff asked how the simulator can model the core as an effective training tool given an online refueling approach, which appears to change the core configuration during operation. Kairos staff described the types of core configurations and noted that the KP-FHR transition core response to transients are benign compared to light-water reactors. Kairos staff will consider updating the TR to discuss this issue.
A member of the public made the following comments:
A member of the public noted that hearing the feedback provided was useful for other applicants and licensees.
A member of the public stated he had been a previously licensed operator at a power reactor facility, and he had performed his required control manipulations in the 1980s as a trainee at a test reactor.
J. Borromeo 4
Enclosure:
List of Attendees cc: Kairos Power Hermes via GovDelivery
J. Borromeo 5
SUBJECT:
SUMMARY
OF APRIL 28, 2025, MEETING WITH KAIROS ON THE PROPOSED TOPICAL REPORT, OPERATOR TRAINING AND TESTING PROGRAM FOR THE KAIROS POWER FLUORIDE SALT-COOLED HIGH-TEMPERATURE TEST REACTORS, AND THE ASSOCIATED EXEMPTION DATED: MAY 14, 2025 DISTRIBUTION:
PUBLIC RidsACRS_MailCTR Resource RidsNrrDanuUal1 Resource RidsNrrDanu Resource JBorromeo, NRR CSantos, NRR DGreene, NRR MOrenak, NRR ABeasten, NRR MDeSouza, NRR TBrown, NRR LNist, NRR TBuchanan, NRR JAnderson, NRR MBalazik, NRR ADAMS Accession Number: ML25105A044 NRR-109 OFFICE NRR/DANU/UAL1:PM NRR/DANU/UAL1:LA NRR/DANU/UAL1:BC NRR/DANU/UAL1:PM NAME CSantos DGreene JBorromeo CSantos DATE 4/30/2025 5/7/2025 5/14/2025 5/14/2025 OFFICIAL RECORD COPY
Enclosure List Of Attendees Summary of Meeting with Kairos April 28, 2025 Name Organization Cayetano Santos U.S. Nuclear Regulatory Commission (NRC)
Michael Orenak NRC Amy Beasten NRC Jim Anderson NRC Lauren Nist NRC Theresa Buchanan NRC Tony Brown NRC Michael Balazik NRC Rachel Lynch Kairos Power, LLC (Kairos)
Drew Peebles Kairos Michael Ellett Kairos Delaney Simmons Kairos Hope Palmer Kairos Anthonie Cilliers Kairos Shane Gallagher Kairos Clara Alivisatos Kairos Sala Tiemann Kairos Nader Satvat Kairos Anna Downing Kairos Mark Chitty Member of the Public Mark Verbeck Member of the Public Jana Bergman Member of the Public Kevin Myers Member of the Public Michael Lazar Member of the Public Michael Protesto Member of the Public Robert White Member of the Public PJ Seel Member of the Public Steven Pope Member of the Public Jon Facemire Member of the Public Mary Miller Member of the Public