ML22039A226

Audit Plan for the Kairos Hermes Preliminary Safety Analysis Report (PSAR) Section 6.3 Decay Heat Removal System - February 2022

ML22039A226
Person / Time
Site:	Hermes File:Kairos Power icon.png
Issue date:	02/17/2022
From:	William Kennedy NRC/NRR/DANU/UARL
To:	Kairos Power
Beasley B; 301-415-2062
References
CAC 000955, EPID L-2021-NEW-0011
Download: ML22039A226 (4)

Text

KAIROS POWER LLC - HERMES CONSTRUCTION PERMIT PRELIMINARY SAFETY ANALYSIS REPORT CHAPTER 6, SECTION 6.3 AUDIT PLAN (CAC/EPID NO. 000955/05007513/L-2021-NEW-0011)

APPLICANT INFORMATION Applicant:

Kairos Power LLC Applicant Address:

707 W. Tower Ave, Alameda, CA 94501 Plant Name(s) and Unit(s):

Kairos - Hermes Test Reactor Docket No(s):

50-7513

Background:

On September 29, 2021, Kairos submitted a preliminary safety analysis report (PSAR)

(Agencywide Documents Access and Management System (ADAMS) Accession No. ML21272A375) 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 its construction permit (CP) application for the proposed Hermes test reactor. The U.S. Nuclear Regulatory Commission (NRC) staff is conducting a detailed review of the CP application. PSAR Chapter 6, Engineered Safety Features, Section 6.3, Decay Heat Removal System (DHRS),

describes the DHRS and its safety function of removing decay heat when the normal heat rejection system is unavailable. This function is credited in the safety analyses of PSAR Chapter 13, Accident Analysis, to maintain acceptable reactor vessel and fuel temperatures.

Purpose:

The purpose of this audit is for the NRC staff to gain a better understanding of Section 6.3, with an emphasis on the DHRS components and how they function together to fulfill the systems safety function. Examining underlying documentation and engaging in audit discussions about the DHRS will facilitate the staffs understanding of the DHRS and its heat removal capability. If the NRC staff identifies information that is needed to support a finding, Kairos will need to submit that information on the application docket.

Regulatory Audit Basis:

The bases for the audit are the regulations of 10 CFR, 50.34(a)(1)(i), 50.34(a)(3), and 50.34(a)(4).

2 Regulatory Audit Scope This audit will focus on information provided by Kairos on the online reference portal.

Information and Other Material Necessary for the Regulatory Audit The NRC staff request more detailed drawing(s)/diagram(s) of the DHRS and its components, in particular, the steam separator and its relationship to the thimbles and float valve as well as an illustration of fluid flow throughout the components/system. In addition, the NRC staff request documentation and/or discussion related to the following topics:

Float valve purpose, fail-open performance, and redundancy.

Parameters to be monitored to ensure availability of DHRS when demanded.

Water supply to the storage tanks and any associated chemistry control.

Potential performance issues (e.g., fouling and instability in the thimbles).

Water tank isolation valve failure mode.

Team Assignments Alex Siwy Nuclear Engineer, Audit Lead responsible for audit summary report preparation Jeff Schmidt Sr. Reactor Systems Engineer Ben Adams General Engineer Alexander Chereskin Materials Engineer, (as needed)

Ben Beasley Senior Project Manager, responsible for audit logistics Ed Helvenston Project Manager Additional audit team members may be added as needed.

Logistics Entrance Meeting February 22, 2022, 1:00 p.m.

Exit Meeting Early April 2022, precise date and time are to be determined Audit meetings will take place in a virtual format, using Microsoft Teams or another similar platform. Audit meetings will be scheduled on an as-needed basis after the entrance meeting and once the NRC staff has had the opportunity to read any documents placed in the online reference portal. The audit duration is anticipated to be approximately six weeks with activities occurring intermittently during that period. The audit period may be reduced or extended, dependent on the NRC staff and Kairos progress in addressing audit questions.

Special Requests None.

Deliverables At the completion of the audit, the audit team will issue an audit summary within 90 days after the exit meeting but will strive for a shorter duration. The audit summary will be declared and entered as an official agency record in ADAMS and be made available for public viewing through the publicly available records component of ADAMS.

3 References Title 10 of the Code of Federal Regulations.

Please contact Ben Beasley at 301-415-2062 or by email at benjamin.beasley@nrc.gov with any questions related to the conduct of the audit.

Date: February 17, 2022 William Kennedy, Acting Chief Advanced Reactor Licensing Branch Division of Advanced Reactors and Non-Power Production and Utilization Facilities Office of Nuclear Reactor Regulation cc: peebles@kairospower.com bryan@kairospower.com gardner@kairospower.com Signed by Kennedy, William on 02/17/22

4

SUBJECT:

KAIROS POWER LLC - HERMES CONSTRUCTION PERMIT PRELIMINARY SAFETY ANALYSIS REPORT CHAPTER 6, SECTION 6.3 AUDIT PLAN (CAC/EPID NO. 000955/05007513/L-2021-NEW-0011)

DATED: FEBRUARY 17, 2022 DISTRIBUTION:

PUBLIC UARL R/F RidsNrrDanu Resource RidsNrrDanuUarl Resource RidsNrrDanuUtb2 Resource RidsNmssRefs Resource RidsOgcMailCenter Resource RidsACRS_MailCTR Resource ADAMS Accession Number: ML22039A226 OFFICE NRR/DANU/UTB2:SRS NRR/DANU/UARL:PM NRR/DANU/UTB2:BC NAME JSchmidt BBeasley SPhilpott DATE 02/14/2022 02/16/2022 02/16/2022 OFFICE NRR/DANU/UARL:BC NAME WKennedy DATE 02/17/2022 OFFICIAL RECORD COPY