ML24240A141

LLC - Response to NRC Request for Additional Information No. 16 (RAI-10134 R1) on the NuScale Standard Design Approval Application

ML24240A141
Person / Time
Site:	05200050
Issue date:	08/27/2024
From:	Shaver M NuScale
To:	Office of Nuclear Reactor Regulation, Document Control Desk
Shared Package
ML24240A140	List: ML24240A141
References
RAIO-173492
Download: ML24240A141 (1)

Text

RAIO-173492

August 27, 2024 Docket No.52-050

U.S. Nuclear Regulatory Commission ATTN: Document Control Desk One White Flint North 11555 Rockville Pike Rockville, MD 20852-2738

SUBJECT:

NuScale Power, LLC Response to NRC Request for Additional Information No. 16 (RAI-10134 R1) on the NuScale Standard Design Approval Application

REFERENCE:

1. NRC Letter to NuScale, Request for Additional Information No. 16 (RAI-10134 R1), dated March 2, 2024

The purpose of this letter is to provide the NuScale Power, LLC (NuScale) response to the referenced NRC Request for Additional Information (RAI).

The enclosure to this letter contains NuScale's response to the following RAI question from NRC RAI-10134 R1:

x 3.6.3-1 is the proprietary version of the NuScale response to NRC RAI No. 16 (RAI-10134 R1). NuScale requests that the proprietary version be withheld from public disclosure in accordance with the requirements of 10 CFR § 2.390. The enclosed affidavit (Enclosure 3) supports this request. Enclosure 2 is the nonproprietary version of the NuScale response.

This letter makes no regulatory commitments and no revisions to any existing regulatory commitments.

If you have any questions, please contact Elisa Fairbanks at 541-452-7872 or at efairbanks@nuscalepower.com.

I declare under penalty of perjury that the foregoing is true and correct. Executed on August 27, 2024.

Sincerely,

Mark W. Shaver Director, Regulatory Affairs NuScale Power, LLC

NuScale Power, LLC 1100 NE Circle Blvd., Suite 200 Corvallis, Oregon 97330 Office 541.360.0500 Fax 541.207.3928 www.nuscalepower.com RAIO-173492 Page 2 of 2 08/27/2024

Distribution: Mahmoud Jardaneh, Chief New Reactor Licensing Branch, NRC Getachew Tesfaye, Senior Project Manager, NRC Prosanta Chowdhury, Senior Project Manager, NRC

Enclosure 1: NuScale Response to NRC Request for Additional Information RAI-10134 R1, proprietary Enclosure 2: NuScale Response to NRC Request for Additional Information RAI-10134 R1, nonproprietary Enclosure 3: Affidavit of Mark W. Shaver, AF-173493

NuScale Power, LLC 1100 NE Circle Blvd., Suite 200 Corvallis, Oregon 97330 Office 541.360.0500 Fax 541.207.3928 www.nuscalepower.com RAIO-173492

NuScale Response to NRC Request for Additional Information RAI-10134 R1, proprietary

NuScale Power, LLC 1100 NE Circle Blvd., Suite 200 Corvallis, Oregon 97330 Office 541.360.0500 Fax 541.207.3928 www.nuscalepower.com RAIO-173492

NuScale Response to NRC Request for Additional Information RAI-10134 R1, nonproprietary

NuScale Power, LLC 1100 NE Circle Blvd., Suite 200 Corvallis, Oregon 97330 Office 541.360.0500 Fax 541.207.3928 www.nuscalepower.com NuScaleNonproprietary

ResponsetoRequestforAdditionalInformation Docket:052000050

RAINo.:10134 DateofRAIIssue:03/02/2024

NRC Question No.: 3.6.3-1

Regulatory Basis 10 CFR Part 50 Appendix-A GDC 4 states that structures, systems, and components shall be appropriately protected against dynamic effects, including the effects of missiles, pipe whipping, and discharging fluids, that may result from equipment failures and from events and conditions outside the nuclear power unit. However, dynamic effects associated with postulated pipe ruptures in nuclear power units may be excluded from the design basis when analyses reviewed and approved by the Commission demonstrate that the probability of fluid system piping rupture is extremely low under conditions consistent with the design basis for the piping.

Issue FSAR Section 3.6.3 states that Leak-Before-Break (LBB) is not used for SDAA. This is a change from the DCA approach where LBB methodology was used. Specifically, for DCA, Pipe Rupture Hazards Analysis Technical Report, TR-0818-61384-P, Revision 2, utilized LBB methodology while the SDAA Pipe Rupture Hazards Analysis TR-121507-P, Revision 0, does not.

In the DCA, LBB methodology was credited to justify exclusion of high energy line breaks in large-diameter secondary piping, namely main steam system (MSS) and feedwater system (FWS) piping. This was noted in section 2.2.2.1.1 of the DCA Technical Report TR-0818-61384-P, Revision 2. NuScale analyzed MSS and FWS piping for LBB and showed them to meet the criteria in the Section 2.2.5 discussion related to SRP 3.6.3. This was also reflected in Section 3.6.3.2 of the DCA Safety Evaluation. However, in the SDAA NuScale does not use LBB methodology for MSS and FWS piping inside containment. This is a significant change in NuScales approach.

Information Requested Provide the basis for break exclusion for the high energy piping (and particularly the MSS and FWS piping) inside containment that account for the change in methodology from DCA to

NuScaleNonproprietary NuScaleNonproprietary

SDAA.Discusschangesindesignparameterssuchaspressure,temperature,andflowrateas aresultofthepowerincreasefromDCAtoSDAA,andwhetherthereareanychangesinMSS andFWSpipingroutinginsidecontainment,andhowtheaboveareconsideredinthe justificationforbreakexclusion.ProvideasummaryofmaximumstressanditslocationforMSS andFWSsystemsforBTP3-4stresscombinationaswellasforASMEservicelevelsA,B,C, andD.DiscusswhethertheleakdetectionsystembasedonpreviousLBBapproachfromDCA remainsduetoachangeinmethodologyinSDAA.

NuScaleResponse:

ExecutiveSummary

Leakbeforebreak(LBB)methodologywasappliedtothemainsteamsystem(MSS)and feedwatersystem(FWS)intheUS600designcertification(DCA).TheUS460standarddesign approvalapplication(SDAA)implementsanalternateapproachunderBranchTechnical Position(BTP)3-4,andextendsthebreakexclusionzoneincertaininstancesaslongasthe additionaldesigncriteriaofBTP3-4B.1.(ii)aresatisfied.CriteriaforbreakexclusionunderBTP 3-4B.1.(ii)includethefollowing:

applicationofmoreconservativestressandfatiguelimitsthanthoserequiredbyASME Code 100percentvolumetricinserviceexaminationofallpipeweldsduringeachinspection interval

BTP3-4B.1.(ii)imposesconservativestresslimitsandinspectionrequirementstoreducethe probabilityofflawinitiationandgrowth.Incontrast,LBBreliesondetectingleakagefromacrack thathasalreadypropagatedthroughthepressureboundary,allowshigheroperatingstresses, andrequiresnoadditionalinspections.

Basisforbreakexclusionforhighenergypipinginsidecontainment

ThebasisandmethodologiesforbreakexclusionaredescribedinPipeRuptureHazards Analysis,TR-121507,Revision0,AppendixA.

Insidecontainment,BTP3-4B.1.(ii)isappliedtothefollowing:

thesteamgeneratorsystem(SGS),mainsteam(MS),andfeedwater(FW)piping theterminalendweldsbetweenthedecayheatremovalsystem(DHRS)pipingandthe containmentvessel(CNV)safeends theboltedconnectionsbetweentheemergencycorecoolingsystem(ECCS)valvesand thereactorpressurevessel(RPV)

NuScaleNonproprietary NuScaleNonproprietary

ChangesindesignparametersasaresultofthepowerincreasefromDCAtoSDAA

TR-121507Table3-3definesthecharacteristicsofthehighenergypiping(including temperatureandpressure)insidetheReactorBuildingfortheSDAA,andiscomparabletothe piperupturehazardsanalysisTR-0818-61384Table3-3fortheDCA.Acomparisonbetween thesevaluesisshownbelowinTable1.

Table1:SGSMSandFWParameterComparison

System Parameter US600DCA US460SDAA OperatingTemperature 585 F 575 F SGSMS DesignTemperature 650 F 650 F OperatingPressure 500psia 700psia DesignPressure 2100psia 2200psia FullPowerSteamFlow 5.321E5lbm/hr 8.14E5lbm/hr OperatingTemperature 300 F 250 F

-F-Ax DesignTemperature 650 F 650 F OperatingPressure 550psia 701psia DesignPressure 2100psia 2200psia

The increase in secondary side operating pressures between the DCA and SDAA is due to operating conditions throughout an operating range of 20 percent to 102 percent power.

Changes to the SGS MS and FW pipe routing are addressed in the current SDAA design. TR-121507 Section A.1.1 describes the application of BTP 3-4 B.1.(ii) and includes considerations for pipe routing.

Summary of maximum stress for MSS and FWS systems

Preliminary stress analyses are performed for the Class 1, 2, & 3 high-energy piping larger than nominal pipe size (NPS) 1 both inside and outside containment in order to confirm the adequacy of the piping layout and support locations, and to support high energy line break evaluations as described in SDAA Section 3.12. Current stress analysis results for the portions of SGS MS and FW lines inside containment are summarized in Table 2 and Table 3 below. High stress locations are shown in Figure 1 and Figure 2.

NuScaleNonproprietary NuScaleNonproprietary

Table2:SteamGeneratorSystemFeedwater&DecayHeatRemovalPipingStress AnalysisResults

((2(a),(c)

NuScaleNonproprietary NuScaleNonproprietary

Figure1:SteamGeneratorSystemFeedwater&DecayHeatRemovalPipingStress AnalysisResultLocations ((

}}2(a),(c)

NuScaleNonproprietary NuScaleNonproprietary

Table3:SteamGeneratorSystemMainSteamPipingStressAnalysisResults ((

}}2(a),(c)

NuScaleNonproprietary NuScaleNonproprietary

Figure2:SteamGeneratorSystemMainSteamPipingStressAnalysisResultLocations ((

}}2(a),(c)

NuScaleNonproprietary NuScaleNonproprietary

LeakagedetectionsystemchangesbetweenDCAandSDAA

TheDCAleakagedetectionsystemsensitivityrequirementis0.001gpmfortheapplicationof theLBBmethodology.TheSDAAleakagedetectionsystemsensitivityrequirementis0.05gpm tomeettheLeakage-Monitoring-RelatedPositionsspecifiedinRG1.45.Theserequirement changesarediscussedfurtherintheresponsetoRAIQuestion3.6.2.7-2.

Conclusion

TheSDAAreflectstheupdateddesignandanalysisoftheUS460standardplantandapplies thebreakexclusionmethodologiesdescribedinPipeRuptureHazardsAnalysis,TR-121507, Revision0,AppendixA,ensuring10CFRPart50Appendix-AGDC4ismet.

ImpactonUS460SDAA:

TherearenoimpactstoUS460SDAAasaresultofthisresponse.

NuScaleNonproprietary RAIO-173492

Affidavit of Mark W. Shaver, AF-173493

NuScale Power, LLC 1100 NE Circle Blvd., Suite 200 Corvallis, Oregon 97330 Office 541.360.0500 Fax 541.207.3928 www.nuscalepower.com NuScale Power, LLC

AFFIDAVIT of Mark W. Shaver

I, Mark W. Shaver, state as follows:

(1) I am the Director of Regulatory Affairs of NuScale Power, LLC (NuScale), and as such, I have been specifically delegated the function of reviewing the information described in this Affidavit that NuScale seeks to have withheld from public disclosure, and am authorized to apply for its withholding on behalf of NuScale.

(2) I am knowledgeable of the criteria and procedures used by NuScale in designating information as a trade secret, privileged, or as confidential commercial or financial information. This request to withhold information from public disclosure is driven by one or more of the following:

(a) The information requested to be withheld reveals distinguishing aspects of a process (or component, structure, tool, method, etc.) whose use by NuScale competitors, without a license from NuScale, would constitute a competitive economic disadvantage to NuScale. (b) The information requested to be withheld consists of supporting data, including test data, relative to a process (or component, structure, tool, method, etc.), and the application of the data secures a competitive economic advantage, as described more fully in paragraph 3 of this Affidavit. (c) Use by a competitor of the information requested to be withheld would reduce the competitors expenditure of resources, or improve its competitive position, in the design, manufacture, shipment, installation, assurance of quality, or licensing of a similar product. (d) The information requested to be withheld reveals cost or price information, production capabilities, budget levels, or commercial strategies of NuScale. (e) The information requested to be withheld consists of patentable ideas.

(3) Public disclosure of the information sought to be withheld is likely to cause substantial harm to NuScales competitive position and foreclose or reduce the availability of profit-making opportunities. The accompanying Request for Additional Information response reveals distinguishing aspects about the response by which NuScale develops its NuScale Power, LLC Response to NRC Request for Additional Information (RAI-10134 R1) on the NuScale Standard Design Approval Application.

NuScale has performed significant research and evaluation to develop a basis for this response and has invested significant resources, including the expenditure of a considerable sum of money.

The precise financial value of the information is difficult to quantify, but it is a key element of the design basis for a NuScale plant and, therefore, has substantial value to NuScale.

If the information were disclosed to the public, NuScales competitors would have access to the information without purchasing the right to use it or having been required to undertake a similar expenditure of resources. Such disclosure would constitute a misappropriation of NuScales intellectual property, and would deprive NuScale of the opportunity to exercise its competitive advantage to seek an adequate return on its investment.

(4) The information sought to be withheld is in the enclosed response to NRC Request for Additional Information RAI-10134 R1 Chapter 3.6.3-1. The enclosure contains the designation Proprietary at the top of each page containing proprietary information. The information considered by NuScale to be proprietary is identified within double braces, (( }} in the document.

AF-173493 Page 1 of 2 (5) The basis for proposing that the information be withheld is that NuScale treats the information as a trade secret, privileged, or as confidential commercial or financial information. NuScale relies upon the exemption from disclosure set forth in the Freedom of Information Act (FOIA), 5 USC § 552(b)(4), as well as exemptions applicable to the NRC under 10 CFR §§ 2.390(a)(4) and 9.17(a)(4).

(6) Pursuant to the provisions set forth in 10 CFR § 2.390(b)(4), the following is provided for consideration by the Commission in determining whether the information sought to be withheld from public disclosure should be withheld:

(a) The information sought to be withheld is owned and has been held in confidence by NuScale.

(b) The information is of a sort customarily held in confidence by NuScale and, to the best of my knowledge and belief, consistently has been held in confidence by NuScale. The procedure for approval of external release of such information typically requires review by the staff manager, project manager, chief technology officer or other equivalent authority, or the manager of the cognizant marketing function (or his delegate), for technical content, competitive effect, and determination of the accuracy of the proprietary designation. Disclosures outside NuScale are limited to regulatory bodies, customers and potential customers and their agents, suppliers, licensees, and others with a legitimate need for the information, and then only in accordance with appropriate regulatory provisions or contractual agreements to maintain confidentiality.

(c) The information is being transmitted to and received by the NRC in confidence.

(d) No public disclosure of the information has been made, and it is not available in public sources. All disclosures to third parties, including any required transmittals to NRC, have been made, or must be made, pursuant to regulatory provisions or contractual agreements that provide for maintenance of the information in confidence.

(e) Public disclosure of the information is likely to cause substantial harm to the competitive position of NuScale, taking into account the value of the information to NuScale, the amount of effort and money expended by NuScale in developing the information, and the difficulty others would have in acquiring or duplicating the information. The information sought to be withheld is part of NuScales technology that provides NuScale with a competitive advantage over other firms in the industry. NuScale has invested significant human and financial capital in developing this technology and NuScale believes it would be difficult for others to duplicate the technology without access to the information sought to be withheld.

I declare under penalty of perjury that the foregoing is true and correct. Executed on August 27, 2024.

Mark W. Shaver MkWSh

AF-173493 Page 2 of 2}}