ML23248A455
| ML23248A455 | |
| Person / Time | |
|---|---|
| Site: | 05200050 |
| Issue date: | 09/11/2023 |
| From: | David Drucker NRC/NRR/DNRL/NRLB |
| To: | Matthew Mitchell NRC/NRR/DNRL/NRLB |
| References | |
| Download: ML23248A455 (6) | |
Text
September 11, 2023 MEMORANDUM TO: Matthew A. Mitchell, Acting Chief New Reactor Licensing Branch Division of New and Renewed Licenses Office of Nuclear Reactor Regulation FROM: David M. Drucker, Senior Project Manager /RA/
New Reactor Licensing Branch Division of New and Renewed Licenses Office of Nuclear Reactor Regulation
SUBJECT:
AUDIT
SUMMARY
FOR U.S. NUCLEAR REGULATORY COMMISSION REQUESTS FOR SUPPLEMENTAL INFORMATION IDENTIFICATION OF SPECIFIC INFORMATION REQUIREMENTS - NUSCALE US460 STANDARD DESIGN APPROVAL APPLICATION By memorandum dated March 22, 2023, (Agencywide Documents Access and Management System (ADAMS) Accession No. ML23067A298), the U.S. Nuclear Regulatory Commission (NRC) staff issued an audit plan to review audit material associated with the technical sufficiency issues in the US460 Standard Design Approval (SDA) application related to density wave oscillation (DWO) documented in the staff acceptance review letter dated March 17, 2023 (ML23058A160). The NRC started the audit with a teleconference entrance meeting on March 27, 2023. The audit was conducted via NuScales electronic reading room (eRR),
teleconferences and an in-person meeting held on April 18-19, 2023, at NuScales Rockville office. During the audit, the NRC staff and NuScale discussed 17 DWO related questions generated by the staff. NuScale responded to the questions in the eRR and submitted the responses on the docket by letter dated July 14, 2023 (ML23195A092 non-proprietary and ML23198A244 proprietary). An audit exit meeting was held on July 20, 2023.
CONTACT: David Drucker, NRR/DNRL Getachew Tesfaye, NRR/DNRL 301-415-6233 301-415-8013 Docket No. 05200050
Enclosure:
Audit summary cc w/encl.: NuScale Power LLC Listserv
ML23248A455 via email* NRR-106 OFFICE DNRL/NRLB: PM DNRL/NLIB: LA DRA/SNRB: TR DRA/SNRB: BC NAME DDrucker* SGreen* ABarrett RPatton DATE 09/05/2023 09/05/2023 09/06/2023 09/06/2023 OFFICE DNRL/NRLB: PM DNRL/NRLB: BC DNRL/NRLB:PM NAME GTesfaye* MMitchell* DDrucker*
DATE 09/10/2023 9/11/2023 9/11/2023 AUDIT
SUMMARY
FOR THE REGULATORY AUDIT OF REQUESTS FOR SUPPLEMENTAL INFORMATION IDENTIFICATION OF SPECIFIC INFORMATION REQUIREMENTS - NUSCALE US460 STANDARD DESIGN APPROVAL APPLICATION
1.0 BACKGROUND
AND PURPOSE By letter dated December 31, 2022 (electronically submitted on January 1, 2023), NuScale Power, LLC (NuScale) transmitted the last part of the required staged submittal of the Standard Design Approval (SDA) application. The submitted documents can be found at Agencywide Documents Access and Management System (ADAMS) Accession No. ML22339A066. The staff completed the acceptance review of the SDA application and issued the acceptance review letter on March 17, 2023 (ML23058A160).
Based on its review, the U.S. Nuclear Regulatory Commission (NRC) staff identified technical sufficiency issues in the SDA application related to density wave oscillation (DWO), with impacts on some parts of the SDA application Part 2, Final Safety Analysis Report (FSAR) Chapters 3, 5, 6, 15 and 19, and the following associated licensing topical reports (LTRs): (1) TR-0516-49422, Loss-of-Coolant Accident [LOCA] Evaluation Model, Revision 3 (ML23008A002); (2)
TR-0516-49416, Non-Loss-of-Coolant Accident Analysis Methodology, Revision 4 (ML23005A305); (3) TR-124587, Extended Passive Cooling and Reactivity Control Methodology, Revision 0 (ML23005A308); and (4) TR-131981, Methodology for the Determination of the Onset of Density Wave Oscillations (DWO), Revision 0 (ML22364A332).
As a result, the NRC staff concluded that supplemental information on this topic was required before the NRC staff could accept the SDA application for docketing and conduct a detailed technical review of all aspects of the application.
By memorandum dated March 22, 2023 (ML23067A298), the NRC staff issued an audit plan to review audit material associated with in the SDA application related to DWO. The purpose of the audit was to review audit material related to DWO so the staff can have adequate understanding of underlying information related to DWO.
2.0 REGULATORY AUDIT BASIS This regulatory audit is based on the submittal of the FSAR documents for its SDA application of the NuScale design (ML22339A066). The bases for the submittal follow the regulations in Title 10 of the Code of Federal Regulations (10 CFR) Part 52, Licenses, Certifications, and Approvals for Nuclear Power Plants, as outlined below:
- 10 CFR Part 52, Subpart E - Standard Design Approvals
- § 52.131 Scope of subpart.
- § 52.133 Relationship to other subparts.
- § 52.135 Filing of applications.
- § 52.136 Contents of applications; general information.
- § 52.137 Contents of applications; technical information.
- § 52.139 Standards for review of applications.
Enclosure
- § 52.141 Referral to the Advisory Committee on Reactor Safeguards.
- § 52.143 Staff approval of design.
- § 52.145 Finality of standard design approvals; information requests.
- § 52.147 Duration of design approval.
3.0 AUDIT LOCATION AND DATES The audit was conducted remotely via NuScales eRR, and Teams meetings. In addition, there was one in-person meeting held on April 18-19, 2023, at NuScales Rockville office.
Dates: March 27, 2023-July 20, 2023 Location: NuScale eRR 4.0 AUDIT TEAM MEMBERS Rebecca Patton, NRR/DSS/SNRB Antonio Barret, NRR/DSS/SNRB Shanlai Wu, NRR/DSS/SNRB Rosie Sugrue, NRR/DSS/SNRB Ron Harrington, NRR/DSS/SNRB Ryan Nolan, NRR/DSS/SNRB Stew Bailey, NRR/DEX/EMIB Yuken Wong, NRR/DEX/EMIB Steve Hambric, NRC contractor Pete Yarsky, RES/DSA/CRAB II Pete Lien, RES/DSA/CRAB II Getachew Tesfaye, NRR/DNRL/NRLB Stacy Joseph, NRR/DNRL/NRLB David Drucker, NRR/DNRL/NRLB 5.0 APPLICANT PARTICIPANTS Thomas Griffith Wren Fowler Erin Blumsack Hiral Kadakia Kevin Fischer 6.0 AUDIT DOCUMENTS The staff did not audit hardcopy documents. NuScale submitted and the NRC staff received a transmittal letter (ML23145A058) with a data disk containing proprietary NuScale DWO data.
7.0 DESCRIPTION
OF AUDIT ACTIVITIES AND
SUMMARY
OF OBSERVATIONS The audit scope covered the following topics related to DWO for the NuScale SDA application and applicable LTRs:
2
- Scope of the methodology for calculating DWO and the full applicability range, conditions, and figures of merit;
- Testing that was performed including test results and test data;
- Comparisons of test data to the analysis models and justification for the applicability of the models for evaluation of the SDA application design; and
- Evaluations for the effect of DWO or other flow instability phenomena on steam generator and decay heat removal system performance SDA application Section 5.4.3 and 6.3) during all operating conditions including normal operation, LOCAs, Non-LOCAs, and extended passive cooling.
During the audit, the NRC staff and NuScale discussed 17 DWO related questions generated by the staff. NuScale responded to the questions in the eRR and submitted the responses by letter dated July 14, 2023 (ML23195A092 non-proprietary and ML23198A244 proprietary).
8.0 EXIT BRIEFING The NRC staff conducted an audit exit meeting via a teleconference on July 20, 2023. The NRC staff summarized their observations.
9.0 OPEN ITEMS AND PROPOSED CLOSURE PATHS Not applicable.
10.0 DEVIATIONS FROM THE AUDIT PLAN Not applicable.
3
11.0 REFERENCES
- 1. NuScale Power, LLC, US460 Standard Design Approval application, December 31, 2022, (ADAMS Accession No. ML22339A066)
- 2. TR-0516-49422, Loss-of-Coolant Accident [LOCA] Evaluation Model, Revision 3 (ADAMS Accession No. ML23008A002)
- 3. TR-0516-49416, Non-Loss-of-Coolant Accident Analysis Methodology, Revision 4 (ADAMS Accession No. ML23005A305)
- 4. TR-124587, Extended Passive Cooling and Reactivity Control Methodology, Revision 0 (ADAMS Accession No. ML23005A308)
- 5. TR-131981, Methodology for the Determination of the Onset of Density Wave Oscillations (DWO), Revision 0 (ADAMS Accession No. ML22364A332)
- 6. Audit Plan for U.S. Nuclear Regulatory Commission Requests for Supplemental Information Identification of Specific Information Requirements - NuScale Standard Design Approval Application, Revision 0 (ADAMS Accession No. ML23067A298) 4