ML23199A317
| ML23199A317 | |
| Person / Time | |
|---|---|
| Site: | 99902100 |
| Issue date: | 08/11/2023 |
| From: | Mallecia Sutton NRC/NRR/DANU/UAL1 |
| To: | George Wilson TerraPower |
| Sutton M | |
| Shared Package | |
| ML23199A318 | List: |
| References | |
| L-2023-TOP-0024, CAC 00431 | |
| Download: ML23199A317 (1) | |
Text
TERRAPOWER, LLC - AUDIT PLAN FOR TOPICAL REPORT NAT-3056, PLUME EXPOSURE PATHWAY EMERGENCY PLANNING ZONE SIZING METHODOLOGY, REVISION 0 (CAC/EPID NO. 00431 / L-2023-TOP-0024)
Applicant:
TerraPower, LLC Applicant Address:
15800 Northup Way, Bellevue, WA 98008 Plant Name:
Natrium Project No.:
99902100
Background:
By letter dated March 20, 2023, TerraPower, LLC (TerraPower) submitted topical report (TR)
NAT-3056, Plume Exposure Pathway Emergency Planning Zone Sizing Methodology, Revision 0 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML23080A045) to the U.S. Nuclear Regulatory Commission (NRC) staff. The TR describes TerraPowers proposed methodology for determining the plume exposure pathway (PEP) emergency planning zone (EPZ) for the Natrium sodium-cooled fast reactor design. On June 12, 2023, the NRC staff found that the TR contained technical information in sufficient detail such that the NRC staff could begin its detailed technical review of the TR (ML23158A198).
TerraPower has requested the NRC staffs review and approval of the PEP EPZ methodology presented in this TR for potential use by applicants using TerraPowers Natrium reactor design as part of future licensing submittals. TerraPowers overall licensing methodology for the Natrium reactor design follows the technology-inclusive, risk-informed, and performance-based approach outlined in Regulatory Guide (RG) 1.233, Guidance for a Technology-Inclusive, Risk-Informed, and Performance-Based Methodology to Inform the Licensing Basis and Content of Applications for Licenses, Certifications, and Approvals for Non-Light Water Reactors, Revision 0 (ML20091L698).
Purpose:
The purpose of the audit is for the NRC staff to gain a detailed understanding of TerraPowers PEP EPZ sizing methodology for the Natrium reactor and how the resulting PEP EPZ will demonstrate compliance with NRC regulations on emergency planning and preparedness, as discussed below. A secondary purpose of the audit is to identify any information that will require docketing to support the NRC staffs safety evaluation for the TR. Therefore, the NRC staff is requesting access to TerraPower documents associated with the development of the PEP EPZ sizing methodology and its use as discussed in the TR. The NRC staff will summarize its observations in an audit report to be provided to TerraPower, as discussed below.
August 11, 2023 Regulatory Audit Basis:
The basis for the audit includes:
Requirements for nuclear power reactor emergency planning, including the requirement for a PEP EPZ, in Title 10 of the Code of Federal Regulations (10 CFR) Section 50.47, Emergency plans, and 10 CFR 50, Appendix E, Emergency Planning and Preparedness for Production and Utilization Facilities.
Requirements for nuclear power reactor EPZ sizing to be described in the emergency plan in 10 CFR 50.33(g) and the following requirements from 10 CFR 50.47(c)(2):
Generally, the plume exposure pathway EPZ for nuclear power reactors shall consist of an area with about 10 miles (16 km) in radius and the ingestion pathway EPZ shall consist of an area with about 50 miles (80 km) in radius. The exact size and configuration of the EPZs surrounding a particular nuclear power reactor shall be determined in relation to the local emergency response needs and capabilities as they are affected by such conditions as demography, topography, land characteristics, access routes, and jurisdictional boundaries. The size of the EPZs also may be determined on a case-by-case basis for gas-cooled reactors and for reactors with an authorized power level less than 250 [megawatts]
thermal. The plans for the ingestion pathway shall focus on such actions as are appropriate to protect the food ingestion pathway.
Although not in the current regulations, the NRC staff also considered relevant information from the ongoing rulemaking on Emergency Preparedness Requirements for Small Modular Reactors (SMRs) and Other New Technologies (ONTs) (Docket NRC-2015-225, rulemaking (Docket NRC-2015-225, https://www.regulations.gov/docket/NRC-2015-0225) (also referred to as the EP for SMRs and ONTs rule). If approved, the rule would amend the NRC's regulations to add alternative EP requirements for SMRs and ONTs such as non-light-water reactors and non-power production or utilization facilities. The rule would adopt a scalable PEP EPZ approach that is performance-based, consequence-oriented, and technology-inclusive. The proposed requirement for the size of the PEP EPZ is based on the determination of the area in which the dose may exceed the Environmental Protection Agency early phase protective action guide levels for a spectrum of events with radioactive material released to the environment.
Regulatory Audit Scope:
The regulatory audit will follow the guidance in NRR Office Instruction LIC-111, Regulatory Audits, (ML19226A274) and focus on information provided by TerraPower in an online reference portal.
Information and Other Material Necessary for the Regulatory Audit:
The NRC staff requests that TerraPower make available the information and/or experts necessary to respond to the audit questions included in the enclosure. The audit questions fall into the following categories:
Introduction and Regulatory Basis
Accident Screening Methodology
Radiological Consequence Considerations
General Team Assignments Michelle Hart Senior Reactor Engineer, Audit Lead Mallecia Sutton Senior Project Manager, Lead Natrium Project Manager Roel Brusselmans Project Manager, Lead Audit Project Manager Hanh Phan Senior Reliability and Risk Analyst Prosanta Chowdhury Senior Emergency Preparedness Specialist Logistics Entrance Meeting August 17, 2023, 3:30 p.m.
Exit Meeting September 15, 2023, 2:00 p.m.
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 review any documents placed in the online reference portal. The audit will begin on August 17, 2023, and continue as necessary, with activities occurring intermittently during the audit period. The audit period may be reduced or extended, depending on the progress made by the NRC staff and TerraPower in addressing audit questions.
Special Requests The NRC staff requests that TerraPower ensure that their technical staff are available to answer questions during the audit. The NRC staff also requests that TerraPower provide access to supporting documents via the TerraPower online reference portal.
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.
If you have questions about this audit, please contact me at 301-415-0673 or via email at Mallecia.Sutton@nrc.gov, or Roel Brusselmans via email at Roel.Brusselmans@nrc.gov.
Sincerely, Mallecia Sutton, Senior Project Manager Advanced Reactors Licensing Branch 1 Division of Advanced Reactors and Non-Power Production and Utilization Facilities Office of Nuclear Reactor Regulation Project No.: 99902100
Enclosure:
As stated cc: TerraPower Natrium via GovDelivery Signed by Sutton, Mallecia on 08/11/23
Package: ML23199A318 Audit Plan: ML23199A317 Audit Questions: ML23199A316 NRR-106 OFFICE NRR/DANU/UAL1/PM NRR/DANU/UAL1/LA NRR/DANU/UTB2 NAME RBrusselmans DGreene MHart DATE 7/19/2023 7/26/2023 7/26/2023 OFFICE NRR/DANU/UART2/BC NRR/DANU/UAL1/BC NRR/DANU/UAL1/PM NAME CdeMessieres WJessup MSutton DATE 8/4/2023 8/10/2023 8/11/2023