ML23117A030
| ML23117A030 | |
| Person / Time | |
|---|---|
| Site: | 99902069, Hermes |
| Issue date: | 04/27/2023 |
| From: | Jose March-Leuba Advisory Committee on Reactor Safeguards |
| To: | David Petti Advisory Committee on Reactor Safeguards |
| References | |
| Download: ML23117A030 (1) | |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION ADVISORY COMMITTEE ON REACTOR SAFEGUARDS WASHINGTON, DC 20555 - 0001 April 27, 2023 MEMORANDUM TO: David Petti, Lead Kairos Power Licensing Subcommittee Advisory Committee on Reactor Safeguards FROM: Jose March-Leuba, Member Advisory Committee on Reactor Safeguards
SUBJECT:
INPUT FOR ACRS REVIEW OF KAIROS NON-POWER REACTOR HERMES CONSTRUCTION PERMIT APPLICATION
- DRAFT SAFETY EVALUATION FOR CHAPTER 11, RADIATION PROTECTION AND WASTE MANAGEMENT In response to the Subcommittees request, I have reviewed the NRC staffs draft safety evaluation (SE) with no open items, and the associated section of the applicants Preliminary Safety Analysis Report (PSAR), for Chapter 11, Radiation Protection and Waste Management.
The following is my recommended course of action concerning further review of this chapter and the staffs associated safety evaluation.
Background
Chapter 11 of the SE report documents the staffs review of the Hermes radiation protection and waste management programs and design provisions as presented in Chapter 11, Radiation Protection and Waste Management, of the Hermes PSAR. The PSAR identifies the sources of radiation at the 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).
It also describes, at a high-level, the Hermes radioactive waste management program and preliminary facility design information for radioactive waste handling.
SE Summary The staff SE report assesses whether Kairos has identified, in sufficient detail, the relevant requirements for an operating facility and has provided descriptions of the preliminary facility design and provisions for protecting the health and safety of the public, workers, and the environment. The goal is 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 applicable regulations. The staff evaluation is based on guidance in NUREG-1537.
The SE report documents the staffs evaluation of the applicants design for compliance with applicable regulations and standards as they apply to a construction permit (CP) application. A more complete evaluation will be performed by the staff once all the details are finalized at the
D. Petti operating license (OL) stage. The NRC staff evaluated the descriptions and discussions of Kaiross and found that they are sufficient and meet the applicable regulatory requirements, guidance, and acceptance criteria for the issuance of a construction permit.
Discussion The sources of radiation that present a potential hazard to workers and the public in the facility result from fission in the fuel (fission products and decay products) and neutron activation products, including tritium, generated as a result of exposure to neutrons. Fission products generated in the TRISO fuel may leak into the Flibe coolant as a result of manufacturing defects in the TRISO layers. The PSAR assumes that TRISO in-service failures and manufacturing defects do not exceed the assumed <0.23%. This assumption is based on experimental data, and it is verified continuously during operation by enforcing a limiting condition for operation (LCO), which is imposed in technical specifications by monitoring Flibe coolant activity. Fission products also may be generated from potential uranium impurities in the reactor coolant. The PSAR also assumes that activation products may be located in the coolant, cover gas, and structures, as a result of neutron activation of various isotopes, corrosion, and wear products.
PSAR Table 11.11, Radiation Sources, lists the potential radiation sources that will be evaluated in detail at the OL stage to ensure compliance with applicable acceptance criteria.
The staff concludes that the information is sufficient and meets the applicable guidance and regulatory requirements for the issuance of a CP. I concur that the information is sufficient at the CP stage, and note that a detailed review, including quantitative analyses, will be performed at the OL stage.
We note that, during normal operation, the primary radiation release is small but related to the generation of tritium in the Flibe coolant by neutron absorption. At the OL stage, the staff should ensure that calculations of tritium generation and leakage are conservative. Special attention should be paid to technical specifications and procedures that minimize tritium production, including control of lithium isotopic concentration and components to scrub and sequester tritium.
I did not identify any specific deficiencies in my review. I would observe that the application was well documented, and the staffs evaluation thorough.
Recommendation As lead reviewer for Hermes SE Chapter 11, I recommend no further action for the PSAR.
D. Petti References
- 1. USNRC, Draft Safety Evaluation for Hermes NonPower Reactor Preliminary Safety Analysis Report Chapter 11, January 2023 (ML23017A120)
- 2. Kairos Power LLC, Submittal of the Preliminary Safety Analysis Report for the Kairos Power Fluoride Salt-Cooled, High Temperature Non-Power Reactor (Hermes), Revision 2, February 2023 (ML23055A672)
- 3. USNRC, NUREG-1537, Part 1, Guidelines for Preparing and Reviewing Applications for the Licensing of Non-Power Reactors, Format and Content, issued February 1996 (ML042430055)
- 4. USNRC, NUREG-1537, Part 2, Guidelines for Preparing and Reviewing Applications for the Licensing of Non-Power Reactors, Standard Review Plan and Acceptance Criteria, issued February 1996 (ML042430048)
D. Petti April 27, 2023
SUBJECT:
INPUT FOR ACRS REVIEW OF KAIROS NON-POWER REACTOR HERMES CONSTRUCTION PERMIT APPLICATION
- DRAFT SAFETY EVALUATION FOR CHAPTER 11, RADIATION PROTECTION AND WASTE MANAGEMENT Package No: ML23117A000 Memo Accession No: ML23117A030 Publicly Available Y Sensitive N Viewing Rights: NRC Users or ACRS Only or See Restricted distribution *via e-mail OFFICE ACRS/TSB* SUNSI Review* ACRS/TSB* ACRS*
NAME WWang WWang LBurkhart JMarch-Leuba DATE 4/27/2023 4/27/2023 4/27/2023 4/27/2023 OFFICIAL RECORD COPY