ML24205A211

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LLC, Response to NRC Request for Additional Information No. 022 (RAI-10157 R1) on the NuScale Standard Design Approval Application
ML24205A211
Person / Time
Site: 05200050
Issue date: 07/23/2024
From: Shaver M
NuScale
To:
Office of Nuclear Reactor Regulation, Document Control Desk
Shared Package
ML24205A210 List:
References
RAIO-172486
Download: ML24205A211 (1)
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RAIO-172486 NuScale Power, LLC 1100 NE Circle Blvd., Suite 200 Corvallis, Oregon 97330 Office 541.360.0500 Fax 541.207.3928 www.nuscalepower.com July 23, 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. 022 (RAI-10157 R1) on the NuScale Standard Design Approval Application

REFERENCE:

1. NRC Letter to NuScale, Request for Additional Information No. 022 (RAI-10157 R1), dated March 20, 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 enclosures to this letter contain NuScale's responses to the following RAI questions from NRC RAI-10157 R1:

x 9.3.4-1 x

9.3.4-2 x

9.3.4-3 is the proprietary response to Question 9.3.4-3 of the NuScale Response to NRC RAI No. 022 (RAI-10157 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 responses to Questions 9.3.4-1, 9.3.4-2 and 9.3.4-3.

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

If you have any questions, please contact Chelsea Lockwood at 541-452-7171 or at clockwood@nuscalepower.com.

I declare under penalty of perjury that the foregoing is true and correct. Executed on July 23, 2024.

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

RAIO-172486 Page 2 of 2 07/23/2024 NuScale Power, LLC 1100 NE Circle Blvd., Suite 200 Corvallis, Oregon 97330 Office 541.360.0500 Fax 541.207.3928 www.nuscalepower.com Distribution:

Mahmoud Jardaneh, Chief New Reactor Licensing Branch, NRC Getachew Tesfaye, Senior Project Manager, NRC Greg Cranston, Project Manager, NRC : NuScale Response to NRC Request for Additional Information RAI-10157 R1, proprietary : NuScale Response to NRC Request for Additional Information RAI-10157 R1, nonproprietary : Affidavit of Mark W. Shaver, AF-172488

RAIO-172486 NuScale Power, LLC 1100 NE Circle Blvd., Suite 200 Corvallis, Oregon 97330 Office 541.360.0500 Fax 541.207.3928 www.nuscalepower.com NuScale Response to NRC Request for Additional Information RAI-10157 R1, proprietary

RAIO-172486 NuScale Power, LLC 1100 NE Circle Blvd., Suite 200 Corvallis, Oregon 97330 Office 541.360.0500 Fax 541.207.3928 www.nuscalepower.com NuScale Response to NRC Request for Additional Information RAI-10157 R1, nonproprietary

Response to Request for Additional Information Docket: 052000050 RAI No.: 10157 Date of RAI Issue:03/20/2024 NRC Question No.: 9.3.4-1 Regulatory Basis 10 CFR Part 50, Appendix A, GDC 1, Quality standards and records. Structures, systems, and components important to safety shall be designed, fabricated, erected, and tested to quality standards commensurate with the importance of the safety functions to be performed. Where generally recognized codes and standards are used, they shall be identified and evaluated to determine their applicability, adequacy, and sufficiency and shall be supplemented or modified as necessary to assure a quality product in keeping with the required safety function.

Issue The demineralized water supply isolation valves perform the safety function to isolate the demineralized water system and terminate an inadvertent boron dilution event. Consistent with its importance to safety, SDAA FSAR Table 9.3.4-3, Classification of Structures, Systems, and Components, classifies the demineralized water isolation valves as safety-related, and seismic Category I. Additionally, SDAA FSAR Table 3.9-16, Active Valve List, identifies the demineralized water isolation valves as ASME Code Section III Class 3 and necessary for accident mitigation.

SDAA Table 9.3.4-3 also classifies the safety-related demineralized water isolation valves as Quality Group D. This is a change from the NuScale US600 design which classified these isolation valves as Quality Group C and the staff subsequently found this treatment acceptable and concluded it is consistent with RG 1.26, Quality Group Classifications and Standards for Water-, Steam-, and Radioactive-Waste-Containing Components of NuScale Power Plants, and GDC 1.

The quality standards applied to Quality Group D SSCs, as delineated in RG 1.26, are not commensurate with the importance to safety of SSCs that perform safety-related functions and are relied on for mitigating design-basis events. Therefore, the staff cannot reach a determination on the adequacy of the current quality group classification of the demineralized water isolation valves.

NuScale Nonproprietary NuScale Nonproprietary

Information Requested The applicant is requested to update the SDAA to classify the demineralized water isolation valves as Quality Group C consistent with RG 1.26 and GDC 1.

NuScale Response:

The chemical and volume control system demineralized water system isolation valves are reclassified as Quality Group C.

Impact on US460 SDAA:

FSAR Sections 2.2, 3.9, and 9.3 have been revised as described in the response above and as shown in the markup provided in this response.

NuScale Nonproprietary NuScale Nonproprietary

NuScale Final Safety Analysis Report Mechanical Systems and Components NuScale US460 SDAA 3.9-87 Draft Revision 2 RAI 9.3.4-1 Table 3.9-16: Active Valve List Valve No.

Description ASME Class Function1 ASME Class 1, 2, and 3 Chemical and Volume Control System CVC-AOV-0336 CVCS Discharge Isolation Valve 3

5 CVC-SV-0404 RPV High Point Degasification Isolation Valve 3

5 CVC-AOV-0089 Demineralized Water Supply to CVC Makeup Upstream Isolation Valve 3

3 CVC-AOV-0090 Demineralized Water Supply to CVC Makeup Downstream Isolation Valve 3

3 Containment System CVC-CKV-0323 Pressurizer Spray Check Valve 3

65 CVC-CKV-0329 CVCS Injection Check Valve 3

65 CVC-HOV-0324 Pressurizer Spray Outboard Containment Isolation Valve 1

1, 2, 3, 4 CVC-HOV-0325 Pressurizer Spray Inboard Containment Isolation Valve 1

1, 2, 3, 4 CVC-HOV-0330 CVCS Injection Outboard Containment Isolation Valve 1

1, 2, 3, 4 CVC-HOV-0331 CVCS Injection Inboard Containment Isolation Valve 1

1, 2, 3, 4 CVC-HOV-0334 CVCS Discharge Inboard Containment Isolation Valve 1

1, 2, 3, 4 CVC-HOV-0335 CVCS Discharge Outboard Containment Isolation Valve 1

1, 2, 3, 4 CVC-HOV-0401 RPV High Point Degasification Inboard Containment Isolation Valve 1

1, 2, 3, 4 CVC-HOV-0402 RPV High Point Degasification Outboard Containment Isolation Valve 1

1, 2, 3, 4 CE-HOV-0001 Containment Evacuation Inboard Containment Isolation Valve 2

2, 3, 4 CE-HOV-0002 Containment Evacuation Outboard Containment Isolation Valve 2

2, 3, 4 CFD-HOV-0021 Containment Flooding & Drain Outboard Containment Isolation Valve 2

2, 3, 4 CFD-HOV-0022 Containment Flooding & Drain Inboard Containment Isolation Valve 2

2, 3, 4 RCCW-HOV-0184 Reactor Component Cooling Water Inlet Outboard Containment Isolation Valve 2

2, 3, 4 RCCW-HOV-0185 Reactor Component Cooling Water Inlet Inboard Containment Isolation Valve 2

2, 3, 4 RCCW-HOV-0190 Reactor Component Cooling Water Outlet Inboard Containment Isolation Valve 2

2, 3, 4 RCCW-HOV-0191 Reactor Component Cooling Water Outlet Outboard Containment Isolation Valve 2

2, 3, 4 FW-HOV-0137 Feedwater Isolation Valve 2

2, 3, 4 FW-HOV-0237 Feedwater Isolation Valve 2

2, 3, 4 FW-CKV-0136 Feedwater Isolation Check Valve 2

3 FW-CKV-0236 Feedwater Isolation Check Valve 2

3 MS-HOV-0101 Main Steam Isolation Valve 2

2, 3, 4 MS-HOV-0201 Main Steam Isolation Valve 2

2, 3, 4 MS-HOV-0103 Main Steam Isolation Bypass Valve 2

2, 3, 4 MS-HOV-0203 Main Steam Isolation Bypass Valve 2

2, 3, 4 Decay Heat Removal System DHR-HOV-0111 Decay Heat Removal System Actuation Valve 2

3, 4 DHR-HOV-0121 Decay Heat Removal System Actuation Valve 2

3, 4 DHR-HOV-0211 Decay Heat Removal System Actuation Valve 2

3, 4 DHR-HOV-0221 Decay Heat Removal System Actuation Valve 2

3, 4

NuScale Final Safety Analysis Report Mechanical Systems and Components NuScale US460 SDAA 3.9-88 Draft Revision 2 Emergency Core Cooling System2 ECC-POV-0001A Reactor Vent Valve A 1

1, 3, 4 ECC-POV-0001B Reactor Vent Valve B 1

1, 3, 4 ECC-POV-0002A Reactor Recirculation Valve A 1

1, 3, 4 ECC-POV-0002B Reactor Recirculation Valve B 1

1, 3, 4 Safety and Relief Valves RCS-PSV-0003A Reactor Safety Valve A 1

1, 3 RCS-PSV-0003B Reactor Safety Valve B 1

1, 3 SGS-RV-0102 Steam Generator System Thermal Relief Valve 2

2 SGS-RV-0202 Steam Generator System Thermal Relief Valve 2

2 Non-Code Class Valves Condensate and Feedwater System FW-AOV-0134 Feedwater Regulating Valve NC 67 FW-AOV-0234 Feedwater Regulating Valve NC 67 FW-CKV-0135 Backup Feedwater Check Valve NC 67 FW-CKV-0235 Backup Feedwater Check Valve NC 67 Main Steam System MS-AOV-0102 SecondaryBackup Main Steam Isolation Valve NC 67 MS-AOV-0202 SecondaryBackup Main Steam Isolation Valve NC 67 MS-AOV-0104 SecondaryBackup Main Steam Isolation Bypass Valve NC 67 MS-AOV-0204 SecondaryBackup Main Steam Isolation Bypass Valve NC 67 1 - Function 1 - Reactor coolant pressure boundary 2 - Containment isolation 3 - Accident mitigation 4 - Safe shutdown 5 - Nonsafety-related, but provide an augmented quality with augmented requirements function (NRC Quality Group C/D boundary) 6 - Nonsafety-related, but provide an augmented quality function (NRC Quality Group C/D boundary, backup containment isolation) 67 - Nonsafety backup to a safety-related function (Section 15.0.0.6.6) 2 - Trip and reset valves are included with each RVV and RRV.

Table 3.9-16: Active Valve List (Continued)

Valve No.

Description ASME Class Function1

NuScale Final Safety Analysis Report Mechanical Systems and Components NuScale US460 SDAA 3.9-89 Draft Revision 2 RAI 9.3.4-1 Table 3.9-17: Valve Inservice Test Requirements per ASME OM Code Valve No.

Description Valve /

Actuator1 Function Position Function(s)2 ASME Class / IST Category IST Type and Frequency3 Valve Group4 Notes Chemical and Volume Control System CVC-AOV-0089 Demineralized Water Supply to CVCS Makeup Upstream Isolation Valve BALL Remote AO Closed Active Boron Dilution Prevention 3NC Category B Position Verification Test/2 Years Exercise Full Stroke/Quarterly Failsafe Test/Quarterly Performance Assessment Test POV 1 5, 16 CVC-AOV-0090 Demineralized Water Supply to CVCS Makeup Downstream Isolation Valve BALL Remote AO Closed Active Boron Dilution Prevention 3NC Category B Position Verification Test/2 Years Exercise Full Stroke/Quarterly Failsafe Test/Quarterly Performance Assessment Test POV 1 5, 16 Condensate and Feedwater System FW-AOV-0134 Feedwater Regulating Valve A FCV Remote AO Closed Active Backup Feedwater Isolation Backup Containment Isolation Backup DHRS Boundary NC Category A Position Verification Test Exercise Full Stroke/Cold Shutdown Failsafe Test/Cold Shutdown Leak Test Performance Assessment Test POV 5 15, 17 FW-AOV-0234 Feedwater Regulating Valve B FCV Remote AO Closed Active Backup Feedwater Isolation Backup Containment Isolation Backup DHRS Boundary NC Category A Position Verification Test Exercise Full Stroke/Cold Shutdown Failsafe Test/Cold Shutdown Leak Test Performance Assessment Test POV 5 15, 17 FW-CKV-0135 Backup Feedwater Check Valve A Nozzle Check Closed Active Decay Heat Removal Boundary NC Category C Check Exercise/ Cold Shutdown CKV 1 18 FW-CKV-0235 Backup Feedwater Check Valve B Nozzle Check Closed Active Decay Heat Removal Boundary NC Category C Check Exercise/ Cold Shutdown CKV 1 18 Containment System CVC-HOV-0324 Pressurizer Spray Outboard Containment Isolation Valve BALL Remote HO Closed Active Reactor Coolant Pressure Boundary Containment Isolation Class 1 Category A Position Verification Test/2 Years Exercise Full Stroke/ Quarterly Failsafe Test/ Quarterly Containment Isolation Leak Test Performance Assessment Test POV 2 6, 16

NuScale Final Safety Analysis Report Chemical and Volume Control System NuScale US460 SDAA 9.3-32 Draft Revision 2 Tank Sampling The discharge of the boric acid transfer pump and the boric acid supply pumps include a sample port to facilitate sampling of the mixture in the BAS batch and storage tanks.

Chemical and Volume Control System Off-Normal Operations Features in the CVCS provide monitoring for system leakage. The cubicles that house the ion exchangers, filters, and resin traps have level switches to detect leakage from those components. The expansion tank has a level transmitter to provide indication of system leakage. The CVCS discharge, injection, makeup, and letdown lines have flow, temperature, and pressure indication for obtaining mass flow rates, which can be used to detect system leakage.

The containment isolation valves (CIVs) on CVCS lines close when specified setpoints for critical parameters are exceeded. Section 6.2, Containment Systems, provides information on the containment isolation function.

The CVCS has automated features that limit the amount and rate of reactivity increase due to an inadvertent boron dilution event. To limit and mitigate inadvertent dilution events, the CVCS incorporates safety-related demineralized water supply isolation valves. Section 7.1, Fundamental Design Principles, describes this safety function.

A radiation monitor on the CVCS discharge line from the RCS, upstream of the RHX, provides CVCS process monitoring and worker protection.

Section 11.5, Radiation Monitoring, provides additional information on this radiation monitor.

9.3.4.3 Safety Evaluation RAI 9.3.4-1 Consistent with GDC 1, CVCS structures, systems, and components (SSC) are designed, fabricated, erected, and tested to appropriate quality standards such that their failure does not impact the function of other safety-related or risk-significant systems. The CVCS is classified as Quality Group D, with the exception of the CVCS demineralized water supply isolation valves, isolation valves which are classified as Quality Group C per RG 1.26.

Consistent with GDC 2, safety-related CVCS components are not adversely affected by natural phenomena such as earthquakes or floods. The safety-related CVCS components are housed in the RXB. The demineralized water supply isolation valves are located below grade in the RXB. The RXB protects against natural phenomena such as tornadoes, seismic events and floods, including the probable maximum flood as described in Section 3.4, Flood Design. The CVCS piping and components located in the module bay are designated as Seismic Category II because of their proximity to safety-related components. The MHS

NuScale Final Safety Analysis Report Chemical and Volume Control System NuScale US460 SDAA 9.3-41 Draft Revision 2 RAI 9.3.4-1 Table 9.3.4-3: Classification of Structures, Systems, and Components SSC (Note 1)

Location SSC Classification (A1, A2, B1, B2)

Augmented Design Requirements (Note 2)

Quality Group/Safety Classification (Ref RG 1.26 or RG 1.143)

(Note 3)

Seismic Classification (Ref. RG 1.29 or RG 1.143) (Note 4)

CVCS, Chemical and Volume Control System All components (except those listed below):

RXB B2 None D

III Demineralized water supply isolation valves RXB A2 None CD I

Hydrogen bottle RXB B2 RG 1.189 D

II

  • Spool piece vent valves
  • Instrument root valves
  • CVC degasification line flexible hose
  • Instrumentation and mechanical ball joints (in module bay)

RXB B2 None D

II BAS, Boron Addition System All components RXB B2 None D

III Note 1: Acronyms used in this table are listed in Table 1.1-1 Note 2: Additional augmented design requirements, such as the application of a Quality Group, Radwaste safety, or seismic classification, to nonsafety-related SSC are reflected in the columns Quality Group / Safety Classification and Seismic Classification, where applicable. Environmental Qualifications of SSC are identified in Table 3.11-1.

Note 3: Section 3.2.2.1 through Section 3.2.2.4 provides the applicable codes and standards for each RG 1.26 Quality Group designation (A, B, C, and D). A Quality Group classification per RG 1.26 is not applicable to supports or instrumentation that do not serve a pressure boundary function. Section 3.2.1.4 provides a description of RG 1.143 classification for RW-IIa, RW-IIb, and RW-IIc.

Note 4: Where SSC (or portions thereof) as determined in the as-built plant that are identified as Seismic Category III in this table could, as the result of a seismic event, adversely affect Seismic Category I SSC or result in incapacitating injury to occupants of the control room, they are categorized as Seismic Category II consistent with Section 3.2.1.2 and analyzed as described in Section 3.7.3.8.

NuScale Final Safety Analysis Report Chemical and Volume Control System NuScale US460 SDAA 9.3-42 Draft Revision 2 RAI 9.3.4-1 Figure 9.3.4-1: Chemical and Volume Control System Diagram (Chemical and Volume Control System Module 1 with Module Heatup System Shown)

Non-Regenerative Heat Exchanger Ion Exchangers Purification Bypass Letdown to LRWS To PSS MHS Heater From CVCS Modules 2, 3, 4, 5, 6 To CVCS Modules 2, 3, 4, 5, 6 Module Heatup System CVCS Module 1 Regenerative Heat Exchanger PZR RPV CNV RCS Discharge Line RCS Injection Line PZR Spray Supply Line To Solid Rad Waste Resin Traps Filters RCCWS RCCWS Expansion Tank Recirculation Pumps

^

^

^

NRHX and Purification Bypass

^

T DP DP DP To PSS Continuous Sample

^

RT

^

T

^

T

^

T To LRWS RPV High Point Degasification Line Containment System (Not Part of CVCS)

Quality Group D Quality Group C To PSS PSS Sample Purge Return

^

T

^

T Makeup Pump A Makeup Pump B DWS LRWS Chemical Addition Tank BAS

^

T

^

T Makeup Cross-Tie NOTES:

1.) ** Safety Related Demineralized Water isolation valveV are Quality Group C.

2.) *** Quantity four ion exchangers as follows: 2 mixed bed, 1 auxiliary, 1 cation.

3.) Simplified diagram - not all equipment shown.

Makeup Line MHS Booster Pump Zinc Addition Skid Nitrogen Distribution System

License Conditions; ITAAC Module-Specific Structures, Systems, and Components Inspections, Tests, Analyses, and Acceptance Criteria (ITAAC) Design Descriptions and ITAAC NuScale US460 SDAA 31 Draft Revision 2 2.2 Chemical and Volume Control System Module 2.2.1 Inspections, Tests, Analyses, and Acceptance Criteria Design Description ITAAC System Description The scope of this section is the CVCS, which is described in FSAR Section 9.3.4.

Each NPM has its own module-specific CVCS.

The CVCS performs the following safety-related system function that is verified by ITAAC.

The CVCS supports the RCS by isolating dilution sources.

Design Commitments The CVCS demineralized water supply isolation valves listed in Table 2.2-3 change position under design-basis temperature, differential pressure, and flow conditions.

The CVCS demineralized water supply isolation valves listed in Table 2.2-3 perform their function to fail to (or maintain) the closed position on loss of motive power under design-basis temperature, differential pressure, and flow conditions.

RAI 9.3.4-1 The CVCS demineralized water supply isolation valves listed in Table 2.2-3 comply with ASME Code Section III requirements for Code Class 3 components.

2.2.2 Inspections, Tests, Analyses, and Acceptance Criteria Table 2.2-1 contains the ITAAC for the CVCS.

License Conditions; ITAAC Module-Specific Structures, Systems, and Components Inspections, Tests, Analyses, and Acceptance Criteria (ITAAC) Design Descriptions and ITAAC NuScale US460 SDAA 32 Draft Revision 2 RAI 9.3.4-1 Table 2.2-1: Chemical and Volume Control System Inspections, Tests, Analyses, and Acceptance Criteria (ITAAC 02.02.xx)

No.

Design Commitment Inspections, Tests, Analyses Acceptance Criteria

01. The CVCS demineralized water supply isolation valves listed in Table 2.2-3 change position under design-basis temperature, differential pressure, and flow conditions.

A test will be performed of the CVCS demineralized water supply isolation valves listed in Table 2.2-3 under preoperational temperature, differential pressure, and flow conditions.

Each CVCS demineralized water supply isolation valve listed in Table 2.2-3 strokes fully open and fully closed by remote operation under preoperational temperature, differential pressure, and flow conditions.

02. The CVCS demineralized water supply isolation valves listed in Table 2.2-3 perform their function to fail to (or maintain) the closed position on loss of motive power under design-basis temperature, differential pressure, and flow conditions.

A test will be performed of the CVCS demineralized water supply isolation valves listed in Table 2.2-3 under preoperational temperature, differential pressure and flow conditions.

Each CVCS demineralized water supply isolation valve listed in Table 2.2-3 performs its function to fail to (or maintain) the closed position on loss of motive power under preoperational temperature, differential pressure, and flow conditions.

03. The CVCS demineralized water supply isolation valves listed in Table 2.2-3 comply with ASME Code Section III requirements for Code Class 3 components.
i. An inspection will be performed of the ASME Code Class 3 as-built component Design Reports required by ASME Code Section III for the CVCS demineralized water supply isolation valves listed in Table 2.2-3.

ii. An inspection will be performed of the ASME Code Class 3 as-built component Data Reports required by ASME Code Section III for the CVCS demineralized water supply isolation valves listed in Table 2.2-3.

i. The ASME Code Section III Design Reports (NCA-3550) exist and conclude that the as-built CVCS demineralized water supply isolation valves listed in Table 2.2-3 meet the ASME Code Section III requirements for Code Class 3 components.

ii. The ASME Code Section III Data Reports exist and conclude that the as-built CVCS demineralized water supply isolation valves listed in Table 2.2-3 meet the ASME Code Section III requirements for Code Class 3 components.

License Conditions; ITAAC Module-Specific Structures, Systems, and Components Inspections, Tests, Analyses, and Acceptance Criteria (ITAAC) Design Descriptions and ITAAC NuScale US460 SDAA 33 Draft Revision 2 RAI 9.3.4-1 Table 2.2-2: Chemical and Volume Control System Inspections, Tests, Analyses, and Acceptance Criteria Additional Information(1)

ITAAC No.

Discussion 02.02.01 The safety-related chemical and volume control demineralized water supply isolation valves are tested by remote operation to demonstrate the capability to perform their function to transfer open and transfer closed under preoperational temperature, differential pressure, and flow conditions.

In accordance with the information provided in FSAR Table 14.2-33, a preoperational test demonstrates that the safety-related chemical and volume control demineralized water supply isolation valves stroke fully open and fully closed by remote operation under preoperational test conditions.

Preoperational test conditions are established that approximate design basis temperature, differential pressure, and flow conditions to the extent practicable, consistent with preoperational test limitations.

02.02.02 The safety-related chemical and volume control demineralized water supply isolation valves are tested to demonstrate the capability to perform their function to fail to the closed position on loss of motive power under preoperational temperature, differential pressure, and flow conditions.

In accordance with FSAR Table 14.2-33, a preoperational test demonstrates that each safety-related chemical and volume control demineralized water supply isolation valve fails closed on loss of motive power (electric power to the valve actuating solenoid(s) is lost, or pneumatic pressure to the valve(s) is lost).

Preoperational test conditions are established that approximate design-basis temperature, differential pressure, and flow conditions to the extent practicable, consistent with preoperational test limitations.

02.02.03 As required by ASME Code Section III NCA-1210, each ASME Code Class 3 component of a nuclear power plant requires a Design Report in accordance with NCA-3550. NCA-3551.1 requires that the drawings used for construction be in agreement with the Design Report before it is certified and be identified and described in the Design Report. It is the responsibility of the N certificate holder to furnish a Design Report for each component and support, except as provided in NCA-3551.2 and NCA-3551.3.

NCA-3551.1 also requires that the Design Report be certified by a registered professional engineer when it is for Class 3 components designed to service loadings greater than design loadings. NCA-3554 requires that any modification of any document used for construction, from the corresponding document used for design analysis, shall be reconciled with the Design Report.

An ITAAC inspection is performed of the ASME Code Class 3 as-built Design Reports for the CVCS demineralized water supply isolation valves listed in Table 2.2-3 to verify that the requirements of ASME Code Section III are met.

The ASME Code Section III requires that documentary evidence be available at the construction or installation site before use or installation to ensure that ASME Code Class 3 components conform to the requirements of the Code. As defined in NCA-9000, a component can be a vessel, pump, pressure relief valve, line valve, storage tank, piping system, or core support structure that is designed, constructed, and stamped in accordance with the rules of Section III. The ASME Code Class 3 CVCS demineralized water supply isolation valves listed in Table 2.2-3 require a Data Report as specified by NCA-1210. The Data Report is prepared by the certificate holder or owner and signed by the certificate holder or owner and the inspector as specified by NCA-8410. The type of individual Data Report forms necessary to record the required code data is specified in Table NCA-8100-1.

An ITAAC inspection is performed of the ASME Code Class 3 as-built Data Reports for the CVCS demineralized water supply isolation valves listed in Table 2.2-3 to (1) ensure that the appropriate Data Reports have been provided as specified in Table NCA-8100-1, (2) ensure that the certificate holder or owner and the authorized nuclear inspector have signed the Data Reports, and (3) verify that the requirements of ASME Code Section III are met.

Note:

1) References to Tables and Figures refer to ITAAC unless the reference specifically states FSAR Tables or Figures.

License Conditions; ITAAC Module-Specific Structures, Systems, and Components Inspections, Tests, Analyses, and Acceptance Criteria (ITAAC) Design Descriptions and ITAAC NuScale US460 SDAA 34 Draft Revision 2 RAI 9.3.4-1 Table 2.2-3: Chemical and Volume Control System Mechanical Equipment Equipment Name Equipment Identifier ASME Section III Code Class Loss of Motive Power Position Demineralized water system supply (DWS) isolation valves CVC-AOV-0089 CVC-AOV-0090 3

Closed

License Conditions; ITAAC Module-Specific Structures, Systems, and Components Inspections, Tests, Analyses, and Acceptance Criteria (ITAAC) Design Descriptions and ITAAC NuScale US460 SDAA 35 Draft Revision 2 RAI 9.3.4-1 Table 2.2-4: Chemical and Volume Control System Inspections, Tests, Analyses, and Acceptance Criteria Top-Level Design Feature Categories ITAAC No.

Design Basis Accident Internal /

External Hazard Radiological PRA & Severe Accident Fire Protection Physical Security 02.02.01 X

02.02.02 X

02.02.03 X

Response to Request for Additional Information Docket: 052000050 RAI No.: 10157 Date of RAI Issue:03/20/2024 NRC Question No.: 9.3.4-2 Regulatory Basis

  • GDC 14, Reactor coolant pressure boundary. The reactor coolant pressure boundary shall be designed, fabricated, erected, and tested so as to have an extremely low probability of abnormal leakage, of rapidly propagating failure, and of gross rupture.
  • GDC 26, Reactivity control system redundancy and capability. Two independent reactivity control systems of different design principles shall be provided. One of the systems shall use control rods, preferably including a positive means for inserting the rods, and shall be capable of reliably controlling reactivity changes to assure that under conditions of normal operation, including anticipated operational occurrences, and with appropriate margin for malfunctions such as stuck rods, specified acceptable fuel design limits are not exceeded. The second reactivity control system shall be capable of reliably controlling the rate of reactivity changes resulting from planned, normal power changes (including xenon burnout) to assure acceptable fuel design limits are not exceeded. One of the systems shall be capable of holding the reactor core subcritical under cold conditions.

Issue SDAA FSAR Table 9.3.4-2, Boron Addition System Major Equipment with Design Data and Parameters, provides a minimum boron concentration for the boron addition system (BAS).

Additionally, SDAA FSAR Section 9.3.4.2.1 states, [t]he BAS stores and transports borated water mixtures with a boron concentration of approximately 4370 ppm However, the SDAA does not prescribe that maximum boron concentration. This value (5600 ppm) was prescribed in the US600 design certification but appears to be removed in the US460 SDAA.

DSRS 9.3.4, Chemical and Volume Control System, provides guidance acceptable to the staff and states, the CVCS design and arrangement should be that all components and piping that NuScale Nonproprietary NuScale Nonproprietary

can contain boric acid will either be heat-traced, located within heated rooms, or maintained at a low enough concentration to prevent precipitation of boric acid.

Absent a specification for the maximum boron concentration in the SDAA, the staff cannot confirm that the CVCS and BAS will prevent the precipitation of boric acid such that the CVCS can continue perform its functions associated with applicable regulations.

Information Requested The applicant is requested to update the SDAA to provide a specification for the maximum boron concentration in the CVCS and BAS.

NuScale Response:

The maximum boron concentration limit for the Boron Addition System or the Chemical and Volume Control System (CVCS) is 6000 ppm based on the minimum system temperature of 50 degrees Fahrenheit. However, the nominal boron concentration in the systems is 4,370 ppm.

Impact on US460 SDAA:

FSAR Section 9.3 has been revised as described in the response above and as shown in the markup provided in this response.

NuScale Nonproprietary NuScale Nonproprietary

NuScale Final Safety Analysis Report Chemical and Volume Control System NuScale US460 SDAA 9.3-25 Draft Revision 2 listed in Table 9.3.4-2, support shutdown of the NPMs within the described limitations.

RAI 9.3.4-2 The BAS stores and transports borated water mixtures with a nominal boron concentration of approximately 4370 ppm, which is soluble in water down to 32 degrees F. The minimum ambient temperature of the RXB, where the BAS equipment is located, is 50 degrees F, so the BAS does not require additional heating to prevent precipitation. The maximum boron concentration for the BAS is 6000 ppm.

9.3.4.2.2 Component Descriptions Chemical and Volume Control System Makeup Pumps Each CVCS includes two makeup pumps that supply the RCS with makeup coolant and control RCS boron concentration by injecting borated water or demineralized water. Check valves and relief valves on the discharge of each pump prevent reverse flow and protect against over-pressurization. Pulsation dampeners on the discharge of each makeup pump reduce pressure pulsation effects of the positive displacement pumps.

Chemical and Volume Control System Recirculation Pumps Each CVCS includes two recirculation pumps that circulate reactor coolant through the purification equipment, and to the MHS heater during startup. The pumps operate at full RCS pressure and normally at lower temperatures than the RCS due to NRHX cooling. During normal recirculation, a single pump provides recirculation flow with the other pump in standby. The standby recirculation pump starts automatically if the running pump trips on high discharge pressure. Check valves at the pump outlets prevent coolant back flow to the purification equipment. The pumps drain to the radioactive waste drain system (RWDS).

Chemical and Volume Control System Regenerative Heat Exchanger Each CVCS includes an RHX assembly. The RHX is sized to maximize thermal efficiency of the CVCS during normal purification conditions. The RHX has vent and drain connections to the RWDS.

Chemical and Volume Control System Non-Regenerative Heat Exchanger Each CVCS includes an NRHX that provides the second stage of cooling by decreasing the temperature of coolant entering the purification equipment to a level compatible with the ion exchange resin. The reactor component cooling water system (RCCWS) provides cooling for the NRHX. To minimize reactor coolant heat loss, a control valve adjusts RCCWS supply to the NRHX based on the outlet temperature of the CVCS. A pressure relief valve on the cooling

NuScale Final Safety Analysis Report Chemical and Volume Control System NuScale US460 SDAA 9.3-40 Draft Revision 2 RAI 9.3.4-2 Table 9.3.4-2: Boron Addition System Major Equipment with Design Data and Parameters Component Description Design Parameter Value Boric Acid Batch Tank Design pressure Atmospheric Design temperature 155 °F Capacity 6000 gallons Minimum bBoron concentration 4000 ppm - 6000 ppm Boric Acid Transfer Pump Design pressure 230 psig Design temperature 155 °F Capacity 145 gpm Variable speed No Boric Acid Storage Tank Design pressure Atmospheric Design temperature 155 °F Capacity 19,000 gallons Minimum bBoron concentration 4000 ppm - 6000 ppm Boric Acid Supply Pumps Design pressure 230 psig Design temperature 155 °F Capacity 66 gpm Variable speed Yes

Response to Request for Additional Information Docket: 052000050 RAI No.: 10157 Date of RAI Issue:03/18/2024 NRC Question No.: 9.3.4-3 Regulatory Basis

  • 10 CFR 52.137(a)(2) requires, A description and analysis of the SSCs of the facility, with emphasis upon performance requirements, the bases, with technical justification, upon which the requirements have been established, and the evaluations required to show that safety functions will be accomplished The description shall be sufficient to permit understanding of the system designs and their relationship to the safety evaluations. Items such asreactor coolant system other engineered safety features shall be discussedThe following power reactor design characteristics will be taken into consideration by the Commission:
  • GDC 1, Quality standards and records. Structures, systems, and components important to safety shall be designed, fabricated, erected, and tested to quality standards commensurate with the importance of the safety functions to be performed. Where generally recognized codes and standards are used, they shall be identified and evaluated to determine their applicability, adequacy, and sufficiency and shall be supplemented or modified as necessary to assure a quality product in keeping with the required safety function.

Issue A standard design approval applicant is required to perform a design-specific probabilistic risk assessment (PRA) and document its description and results in the application. The capability of the CVCS to provide makeup inventory to the RCS is relied on in several sequences in the PRA. FSAR Table 19.1-3 identifies the CVCS check valve locations and CVCS flow area restrictions as key design features resulting from the PRA analyses for minimizing the likelihood of a break outside containment and reducing large release frequency and the conditional NuScale Nonproprietary NuScale Nonproprietary

containment failure probability, respectively. The staff notes that the use of a CVCS flow area restriction would also play a significant role in any design-basis loss of reactor coolant inventory outside of containment. However, the staff could not find any information detailing the CVCS flow restriction feature in the FSAR.

Information Requested The applicant is requested to update the SDAA to provide necessary information in the design sections of the FSAR (e.g., Chapters 5, 6, 9, etc.) for the CVCS flow restriction design features.

This information should include, but is not limited to, a description of the design feature, component specifications and classification information, and drawings or figures detailing its location(s) and orientation.

NuScale Response:

Final Safety Analysis Report Section 6.2.1 is revised to include the requested design information for the chemical volume and control system venturi flow restrictors. This update includes a description of the design features, purpose, and function as well as the details on the location and orientation of the venturi flow restrictors. The flow restricting venturis are installed into the containment vessel nozzle safe ends of the chemical and volume control system injection and discharge line penetrations. The flow restricting venturis are nonstructural attachments with a non-pressure-retaining function as defined by the ASME Code,Section III, Article NE-1132. The ASME Class boundaries are shown in Figure 1 below.

NuScale Nonproprietary NuScale Nonproprietary

Figure 1: Flow Restricting Venturi ASME Class Boundary ((2(a),(c), ECI Impact on US460 SDAA: FSAR Section 6.2 has been revised as described in the response above and as shown in the markup provided in this response. NuScale Nonproprietary NuScale Nonproprietary

NuScale Final Safety Analysis Report Containment Systems NuScale US460 SDAA 6.2-5 Draft Revision 2 penetration assemblies or appurtenances attached to the CNV, piping, and valves attached to the CNV or to penetration assemblies out to and including the pressure boundary materials of valves required to isolate the system and provide a pressure boundary for the containment function. The CNV components and penetrations (piping, electrical and instrumentation and controls (I&C)) are designed and tested to harsh environment conditions (temperature, pressure, radiation, and submergence). Chapter 3 contains additional component design detail. The CNV inspection and testing of its appurtenances ensure maintenance of leak tightness and functional capability under calculated design-basis conditions. The CNV supports the leakage testing requirements of 10 CFR 50 Appendix J, with the exception of Type A testing as discussed in Section 3.1.5, Section 6.2.6, and Technical Report TR-123952. Access allows for inspections, testing and maintenance of components contained within the CNTS that are within the scope of the inservice inspection (ISI) program and the inservice testing (IST) program during the life of the plant. The CNV design allows for the inspection, testing, and maintenance of equipment and structural features inside containment (control rod drives, ECCS valves (including their venturis), RSVs, pressurizer heaters, instruments, electrical connections, welds, supports, and piping inside containment). RAI 9.3.4-3 The NPM contains two vertically oriented flow-restricting venturis in the containment vessel penetrations (i.e., within the containment system boundary), one for the CVCS injection line flow path and one for the CVCS discharge line flow path, that connects to the RCS via containment. The venturis are designed as inserts installed into the containment vessel nozzle safe-ends inside containment. Due to the venturis being internal inserts, they are not part of the ASME Code pressure boundary and quality group assignment is not applicable. The inserts are classified as nonstructural attachments and designed as Seismic Category I per RG 1.29. The venturis provide passive mitigation of design-basis CVCS breaks outside containment by limiting break flow until CVCS isolation has occurred. The venturis also provide passive mitigation of beyond design-basis unisolated CVCS breaks outside containment as identified in Table 19.1-3. The diameter of the CVCS flow-restriction venturi is 0.844 inches or less. The CNTS components, and their associated supports, facilitate the ASME BPVC, Section XI (Reference 6.2-5) inspection requirements for Class 1, Class 2, and Class MC, including the preservice inspection requirements. Section 3.8.2 provides the CNV design information addressing structural loads and loading combinations.

RAIO-172486 NuScale Power, LLC 1100 NE Circle Blvd., Suite 200 Corvallis, Oregon 97330 Office 541.360.0500 Fax 541.207.3928 www.nuscalepower.com Affidavit of Mark W. Shaver, AF-172488

AF-172488 Page 1 of 2 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 No. 10157, Question 9.3.4-3) 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 10157 Question 9.3.4-3. 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-172488 Page 2 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 July 23, 2024. Mark W. Shaver M k W Sh}}

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