ML23335A200
| ML23335A200 | |
| Person / Time | |
|---|---|
| Site: | 99902078 |
| Issue date: | 12/01/2023 |
| From: | NRC |
| To: | NRC/NRR/DNRL/NRLB |
| References | |
| Download: ML23335A200 (4) | |
Text
From:
Getachew Tesfaye Sent:
Friday, December 1, 2023 5:12 PM To:
Request for Additional Information Cc:
Alina Schiller; Mahmoud Jardaneh; Griffith, Thomas; Fairbanks, Elisa; NuScale-SDA-720RAIsPEm Resource
Subject:
NuScale SDAA Section 19.5 - Request for Additional Information No. 012 (RAI-10113-R1)
Attachments:
SECTION 19.5 - RAI-10113-R1-FINAL.pdf Attached please find NRC staffs request for additional information (RAI) concerning the review of NuScale Standard Design Approval Application for its US460 standard plant design (Agencywide Documents Access and Management System (ADAMS) Accession No. ML222339A066).
Please submit your technically correct and complete response by the agreed upon date to the NRC Document Control Desk.
If you have any questions, please do not hesitate to contact me.
Thank you, Getachew Tesfaye (He/Him)
Senior Project Manager NRC/NRR/DNRL/NRLB 301-415-8013
Hearing Identifier:
NuScale_SDA720_RAI_Public Email Number:
21 Mail Envelope Properties (BY5PR09MB5682BF0A91157C546074B2F38C81A)
Subject:
NuScale SDAA Section 19.5 - Request for Additional Information No. 012 (RAI-10113-R1)
Sent Date:
12/1/2023 5:12:23 PM Received Date:
12/1/2023 5:12:27 PM From:
Getachew Tesfaye Created By:
Getachew.Tesfaye@nrc.gov Recipients:
"Alina Schiller" <Alina.Schiller@nrc.gov>
Tracking Status: None "Mahmoud Jardaneh" <Mahmoud.Jardaneh@nrc.gov>
Tracking Status: None "Griffith, Thomas" <tgriffith@nuscalepower.com>
Tracking Status: None "Fairbanks, Elisa" <EFairbanks@nuscalepower.com>
Tracking Status: None "NuScale-SDA-720RAIsPEm Resource"
<NuScale-SDA-720RAIsPEm.Resource@usnrc.onmicrosoft.com>
Tracking Status: None "Request for Additional Information" <RAI@nuscalepower.com>
Tracking Status: None Post Office:
BY5PR09MB5682.namprd09.prod.outlook.com Files Size Date & Time MESSAGE 585 12/1/2023 5:12:27 PM SECTION 19.5 - RAI-10113-R1-FINAL.pdf 143759 Options Priority:
Normal Return Notification:
No Reply Requested:
No Sensitivity:
Normal Expiration Date:
1 REQUEST FOR ADDITIONAL INFORMATION No. 012 (RAI-10113-R1)
BY THE OFFICE OF NUCLEAR REACTOR REGULATION NUSCALE STANDARD DESIGN APPROVAL APPLICATION DOCKET NO.
05200050 CHAPTER 19, PROBABILISTIC RISK ASSESSMENT AND SEVERE ACCIDENT EVALUATION SECTION 19.5, ADEQUACY OF DESIGN FEATURES AND FUNCTIONAL CAPABILITIES IDENTIFIED AND DESCRIBED FOR WITHSTANDING AIRCRAFT IMPACTS ISSUE DATE: 12/01/2023
=
Background===
By letter dated December 31, 2022, NuScale Power, LLC (NuScale or the applicant) submitted Part 2, Final Safety Analysis Report (FSAR), Chapter 19, "Probabilistic Risk Assessment and Severe Accident Evaluation," Revision 0 (Agencywide Documents Access and Management System Accession No. ML22365A010) of the NuScale Standard Design Approval Application (SDAA) for its US460 standard plant design. The applicant submitted the US460 plant SDAA in accordance with the requirements of Title 10 of the Code of Federal Regulations (10 CFR) Part 52, Licenses, Certifications, and Approvals for Nuclear Power Plants, Subpart E, Standard Design Approvals. The NRC staff has reviewed the information provided in Chapter 19 of the SDAA and determined that additional information is required to complete its review.
Question 19.5-13 Regulatory Basis 10 CFR 50.150(a)(1) requires a design-specific assessment of the effects on the facility of the impact of a large commercial aircraft, and using realistic analyses, the applicant shall identify and incorporate into the design those design features and functional capabilities to show that, with reduced use of operator actions: (i) The reactor core remains cooled, or the containment remains intact; and (ii) Spent fuel cooling or spent fuel pool integrity is maintained. In addition, 10 CFR 50.150(b) requires that the Final Safety Analysis Report (FSAR) contain a description of the design features and functional capabilities and how the design features and functional capabilities meet the assessment requirements.
Issue FSAR Section 19.5 identifies and describes the decay heat removal system (DHRS) and reactor coolant system (RCS) as key design features credited in the aircraft impact assessment (AIA) necessary for core cooling. FSAR 19.5 also states that all required operator actions occur before the aircraft impact, and there are no control or protective functions necessary after aircraft impact for 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. However, in the NuScale US460 design, after 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> following a reactor trip the emergency core cooling system (ECCS) is automatically actuated. Therefore, a realistic plant response for the NuScale US460 to an aircraft impact includes decay heat removal to satisfy core cooling functions via the RCS, DHRS, ECCS, and other support systems already identified and described in FSAR Section 19.5.
2 Information Requested In accordance with 10 CFR 50.150(a)(1) and (b), the applicant is requested to (1) identify in FSAR Section 19.5 that the ECCS is a key design feature for core cooling; and (2) include a description of the design feature and functional capabilities or a reference to where this information is already provided in the FSAR.