ML18302A409

LLC - Submittal of Response to Request for Additional Information (Rals) on NuScale Closure Plan for Final Safety Analysis Report, Tier 2, Sections 3.7 and 3.8

ML18302A409
Person / Time
Site:	NuScale
Issue date:	10/29/2018
From:	Rad Z NuScale
To:	Document Control Desk, Office of New Reactors
Shared Package
ML18302A408	List: ML18302A409
References
LO-1018-62277
Download: ML18302A409 (17)

Text

LO-1018-62277 October 29, 2018 Docket No.52-048 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk One White Flint North 11555 Rockville Pike Rockville, MD 20852-2738

SUBJECT:

NuScale Power, LLC Submittal of NuScale Closure Plan for Final Safety Analysis Report, Tier 2, Sections 3.7 and 3.8 Request for Additional Information (RAls)

REFERENCE:

Request for Seismic Design Issues Closure Plan for the Nu Scale Power, LLC, January 22, 2018, Gregory Cranston to Thomas Bergman (ML17348A916)

The purpose of this letter is to transmit the closure plan requested in Reference 1 for the Chapter 3 (Structural) RAI Responses. This closure plan includes the approach NuScale will take to respond to the RAI questions, the actions to be performed for closing and completing each response, and a schedule for submitting the final responses. This closure plan also includes updates from discussions held at the ongoing bi-weekly meetings between NRC and NuScale on this subject. is the proprietary version of the NuScale Closure Plan for FSAR Sections 3.7 and 3.8 RAls. 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 1) supports this request. is the nonproprietary version of the document entitled NuScale Closure Plan for FSAR Sections 3.7 and 3.8 RAls.

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

If you have any questions, please contact Marty Bryan at 541-452-7172 or at mbryan@nuscalepower.com.

Sin~ff~

Zackary W. Rad Director, Regulatory Affairs NuScale Power, LLC Distribution: Gregory Cranston, NRC, OWFN-8G9A Samuel Lee, NRC, OWFN-8G9A Mariela Vera, NRC, OWFN-8G9A : NuScale Closure Plan for FSAR Sections 3.7 and 3.8 RAls, proprietary version : NuScale Closure Plan for FSAR Sections 3.7 and 3.8 RAls, nonproprietary version : Affidavit of Zackary W. Rad, AF-1018-62347 NuScale Power, LLC 1100 NE Circle Blvd , Suite 200 Corvallis, Oregon 97330 Office 541.360-0500 Fax 541.207.3928 www.nuscalepower.com

LO-1018-62277 NuScale Closure Plan for FSAR Sections 3.7 and 3.8 RAIs - 10/30/2018 Attachment 2 With Interfacing RAI Status Page 1 of 13 eRAI Question# RAI Question Plan Schedule 1 8971 03.08.04-13 10 CFR 50, Appendix A, GDC 1, 2, and 4, provide requirements to be met by 1) Provide the magnitude rebar strains for pilasters, walls and basemat resulting from thermal 12/11/2018 SSC important to safety. In accordance with these requirements, DSRS loads To, Ta and Pa.

Section 3.8.4 provides review guidance pertaining to the design of seismic 2) Describe how load combination 10 was determined to be the controlling load comination Category I structures, other than the containment. Consistent with DSRS instead of load combination 13 Section 3.8.4, the staff reviews loads and loading combinations. The following approach will be taken to address the above information:

FSAR Section 3.8.4.4.1 indicates that an ANSYS model was created to - The rebar strains will be extracted from the finite element models for To, Ta and Pa.

evaluate the effects of thermal loads on the structure. Further, FSAR Section - Clarify whether these extracted forces and moments are used in load combinations 10 3.8.4.5 indicates that load combination 10 from Table 3.8.4-1 has been and 13, if so how.

determined to be the controlling load combination. The staff request the - The treatment of To and Ta induced rebar strains is to be substantiated with quantitative applicant to provide the following information. information justifying the treatment of such effects in the RXB design. (This comment is a) Magnitude of the bounding forces and moments profiles for walls and applicable to the entire RXB, including pilasters, walls, basemat, etc...)

basemat resulting from thermal loads, To and Ta. Clarify whether such - Review the determination of the controlling load combination, including an example of values were used in the load combinations 10 and 13 in Tables 3.8.4-1. how the loads were combined in load combinations 10 and 13 including To and Ta b) Describe how load combination 10 was determined to be the controlling and other non thermal loads.

load combination instead of load combination 13, and provide an example of - Revise FSAR Section 3.8.4 text and tables 3.8.4-1.

how the loads were combined. To clarify RAI 8967, Question 3.8.4-6, we will provide a description of how temperature induced loads were addressed in the design of the pilasters and provide a basis for the treatment of temperature induced loads. And the basis for the treatment of piping and equipment reactions (Ro).

The design check for the reactor building (RXB) in FSAR was performed for the load combinations involving static loads, dynamic loads (Ess) and equivalent static loads from hydrodynamic pressure inside the pool (Referred to as SDH in the following load combinations).

These loads are parts of Load Combinations 9-6 and 9-9 as defined in Section 9.2.1 of ACI 349-

06. However, the design criteria for the RXB include load combinations that contain operating temperature (T0), accident temperature (Ta), and accidental pressure (Pa) effects. The third bullet in Section 1.3 of ACI 349.1R-07 (Reference 6) states the following:

"In nuclear power structures, the controlling load combinations are generally those that include Eo and Ess. These load cases provide sufficient reinforcement to control cracking. It would be counterproductive to add reinforcement to mitigate thermal effects because the additional reinforcement would stiffen the structure, thus increasing the stresses due to thermal effects.

This is unnecessary because thermal effects typically self-relieve without the need for additional reinforcement."

In order to provide response to to the RAI, the thermal loads T0 and Ta, and the pressure load Pa are now defined and hence the design check evaluation is enhanced for the load combinations of equations 9-6 and 9-9 of the ACI 349-06 code. The two load combinations that involve T0, Ta, and Pa are shown below:

• LC 9-6: COMB-Static (1GZ+H+F+0.8L) + Ess + 0.28GZ + T0 = SDH + T0

• LC 9-9: COMB-Static (1GZ+H+F+0.8L) + Ess + 0.28GZ + Ta + Pa = SDH + Ta + Pa For the design check with thermal and accidental pressure load, the total strain in the reinforcing steel calculated and determined to be less than 1.2y, the section is considered acceptable based on the 4th bullet in Section 1.3 of ACI 349.1R-07, which states the following about the reinforcing steel strain with thermal gradient, 1.2y: "Such an exceedance is inconsequential, and will not reduce the capacity of the concrete section for mechanical loads." Therefore, our effort has focused on using a detailed ANSYS 3D FEA model that explicitly include the section rebars (roof, walls, slabs, pilasters, buttresses, and foundation) to determine the new design demands that are additive the SDH loads.

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LO-1018-62277 NuScale Closure Plan for FSAR Sections 3.7 and 3.8 RAIs - 10/30/2018 Attachment 2 With Interfacing RAI Status Page 2 of 13 eRAI Question# RAI Question Plan Schedule 2 8911 03.09.02-18 10 CFR 52.47 requires the design certification applicant to include a Service Level D Evaluation of Internals 10/25/2018 description and analysis of the structures, systems, and components (SSCs) sufficient to permit understanding of the system designs. TR-0916-51502-P, NuScale is currently working on the RVI and SG Level D stress analysis and expects to provide 11/21/2018 Rev. 0, NuScale Power Module Seismic Analysis describes the the RAI responses by the specified due date.

methodologies and structural models that are used to analyze the dynamic The responses will be based on two stress analysis documents:

structural response due to seismic loads acting on the NuScale Power (1) The SG stress analysis uses the latest SSE ISRS and all other applicable loadings for Level Module (NPM). The description is insufficient for staff to reach a safety D, to qualify steam generator tubes and tube supports; finding. Specifically, the report does not provide the seismic and LOCA stress (2) The RVI stress analysis uses the latest SSE ISRS and all other applicable loadings for Level results. Please provide the seismic analysis details and stress results under D, to qualify all the internal components except for SG tubes and tube supports; Service Level D condition for the following reactor internals components.

Include the requested information in the NPM Seismic Report or in separate The stress analysis results are not intended to be included as part of the seismic technical report.

reports.

- core support assembly (core barrel, lower core plate, reflector, upper core plate, - upper core support)

- lower riser assembly

- upper riser assembly (upper riser, upper riser hanger support)

- control rod assembly guide tube, control rod assembly guide tube support, control rod assembly card, control rod drive shaft, and control rod drive shaft support - steam generator tubes and tube supports

- control rod assembly guide tubes The component analysis should include a brief description of the component structure modelling, input motion (time history or in-structure response spectrum), major assumptions, acceptance criteria under Service Level D condition including stress and deflection limits, fluid modelling, mass distribution, damping values, gap considerations, dominant modes and frequencies, and seismic and LOCA stress results and ASME B&PV Code Section III stress evaluation under Service Level D condition.

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LO-1018-62277 NuScale Closure Plan for FSAR Sections 3.7 and 3.8 RAIs - 10/30/2018 Attachment 2 With Interfacing RAI Status Page 3 of 13 eRAI Question# RAI Question Plan Schedule 3 8933 03.07.02-16 In FSAR Section 3.7.2.1.2.1, the staff noted that the dry dock is assumed to NuScale will provide, in a RAI response, further clarification of the operating band level for the 10/31/2018 be full of water and part of the UHS in the seismic analysis. The nominal RXB pool water. In addition, a description of the dry dock gate analysis and design criteria to water level is at EL. 94 ft. In FSAR Section 9.1.3, the staff also noted that the ensure that no adverse seismic interaction occurs between the dry dock gate and adjacent dry dock can be drained partially or completely to support plant operations. In SSCs. The maximum design loads for the dry dock gate occur when the pool is full. Technical FSAR Section 9.1.3.3.5, the staff further noted that a failure of the dry dock justification will be provided through a parametric study comparing design forces with an empty gate while the dry dock is empty could result in a decrease in water level at dry dock for confirmation to show that the dry dock gate has been designed to the bounding load the UHS pool by about 12 ft. Since the dry dock contains a large body of case and will not fail under a safe shutdown earthquake (SSE). With this, NuScale does not water, draining of a large mass of water could affect the dynamic believe it is necessary to account for a 12 foot drop in the UHS pool water level in the dynamic characteristics of the SASSI and ANSYS models thereby potentially affecting analyses. To support the response:

the seismic demand based on full dry dock assumption. Provide a technical basis for not considering different water level conditions for the dry dock in 1. A sensitivity study will be performed which assesses the global response of the structure the seismic analysis. In addition, the applicant should address the effect of when the dry dock is empty. The study will look at the empty dry dock effects within the structure potential variation in water level of the UHS on the seismic analysis of the at key locations to ensure that adequate margin is maintained in this scenario. This will be done RXB and NPM including the analyses conducted in FSAR 3.7.2.9.1 to by comparing ISRS and transfer functions at locations in the structure such as the module address the effect of operation with less than the full complements of NPMs. support, pool floor, and roof.

• Description of the SSI analysis with the empty dry dock including the parameters; e.g., cracked and/or uncracked model, structural damping values, and the soil properties, as well as the input spectra (CSDRS, CSDRS-HF) selected for the study and their basis.

• Markup of appropriate FSAR Sections (e.g., 3.7, 3.8, 9.1.3, etc.)

2. Clarify that we only have a 1 foot operating band of water level, and make revisions to FSAR Sections in chapter 9 as necessary , and thus there really is no effect of the variation of water level 4 9309 03.08.04-37 In its response to RAI 8971, Question 03.08.04-12, the applicant indicated 1) Provide the technical basis that demonstrates the adequacy of the RXB to withstand the 12/11/2018 that the jet impingement, pipe break reaction, and missile impact loads are to demands from Load Combinations 13 and 17 be addressed by the COL applicant as per COL items 3.6- 2 and COL item 2) Provide clarification regarding the locations in the RXB where respective loads are expected 3.6-3. Based on the applicants response, it is not clear to the staff what to occur and address the comparison of the site-specific loadings with the standard design provisions have been incorporated in the current design to accommodate the loadings as in the existing COL item 3.8-2.

aforementioned loads that will be established by the COL applicant and are to be combined with other loads as per Load Combinations 13 and 17 in The following approach will be taken to address the above information:

FSAR Tables 3.8.4-1 and 3.8.4-2, respectively. Therefore, the staff request the applicant to provide the technical basis that demonstrate the adequacy of - Describe preliminary locations of high energy pipe locations in the RXB.

the RXB to withstand the demands from Load Combinations 13 and 17. - Provide the magnitude of the resulting or assumed loads for jet impingement, pipe break and Additionally, the staff requests the applicant to clarify the locations in the missile impact with description of technical basis or assumption RXB where these loads are expected to occur and address the comparison - Evaluate pipe break and describe mass and energy ventilation strategy of the site-specific loadings (as per load combinations 13 and 17) with the - Show that for representative areas that the structural elements are adequate. If these locations standard design loadings in the existing COL item 3.8-2 or a new COL item. are not previously addressed in FSAR, add new design details.

Further, the staff request the applicant to update the FSAR markups

• D/C ratios for areas subject to jet impingement, pipe break reaction, and missile impact loads.

proposed in its response to RAI 8971, Question 03.08.04-12, as applicable.

• Additional FSAR Sections to be updated including Section 3.6, 3.8.4.8 (and other 3.8.4 subsections as applicable), Appendix 3B, and other chapter 3 section as applicable.

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LO-1018-62277 NuScale Closure Plan for FSAR Sections 3.7 and 3.8 RAIs - 10/30/2018 Attachment 2 With Interfacing RAI Status Page 4 of 13 eRAI Question# RAI Question Plan Schedule 5 9447 03.11-19 This is a follow-up RAI to eRAI 9160. NRC concern: FSAR Chapter 3 safety analysis currently assumes a vented bioshield and the 11/20/2018 NuScale's FSAR Chapter 3 describes that the environmental conditions of bioshield vents (relief panels) are nonsafety-related, FSAR Chapter 3 safety analysis (e.g., under design basis accidents under the bioshield are established assuming a the bioshield HELB environmental conditions for pressure and temperature) should be revised vented bioshield (Appendix 3C and Figure 3C-3). In a response to RAI 9160, assuming bioshield venting is not achieved by the relief panels. Otherwise, NuScale will need to the applicant describes that the bioshield relieves (i.e., vents) the high provide additional information to justify reliance on the bioshield relief panels (vents) in its safety pressure and temperature environment under the bioshield by opening relief analysis.

panels. The panels are required to change position from normally closed to open in order to vent the atmosphere under the bioshield into the reactor NuScale position:

building. The panels are hinged and provide one-way relief (venting) in response to a HELB under the bioshield. NuScale is working to redesign the bioshield with the goal of eliminating the blow-out panels. This work is related to the HELB work and there are monthly meetings between NRC and NuScale to NuScale's response to RAI 9160 describes in part that all the bioshield update the status of development. A meeting was held 8/16/2018.

functions, including the venting function, are nonsafety-related. If the function of a component or part is nonsafety- related, the staff expects that its failure to function could not prevent the satisfactory performance of a safety-related function. As discussed above, NuScale's FSAR Chapter 3 safety analysis, which establishes the environmental conditions under the bioshield for items related to safety, currently assumes a vented bioshield (e.g., opening nonsafety-related relief panels discussed in response to RAI 9160).

Therefore, the staff requests NuScale to assess the failure of the venting function (i.e., nonsafety-related bioshield relief panels do not open) and its impact on the performance of equipment important to safety (e.g., safety-related).

As part of the response, because the FSAR Chapter 3 safety analysis currently assumes a vented bioshield and the bioshield vents (relief panels) are nonsafety-related, FSAR Chapter 3 safety analysis (e.g., under the bioshield HELB environmental conditions for pressure and temperature) should be revised assuming bioshield venting is not achieved by the relief panels. Otherwise, NuScale will need to provide additional information to justify reliance on the bioshield relief panels (vents) in its safety analysis.

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LO-1018-62277 NuScale Closure Plan for FSAR Sections 3.7 and 3.8 RAIs - 10/30/2018 Attachment 2 With Interfacing RAI Status Page 5 of 13 eRAI Question# RAI Question Plan Schedule 6 8932 03.07.02-5 10 CFR 50 Appendix S requires that the safety functions of structures, NuScale will provide, through the RAI response, additional transfer function plots at key nodes in 11/29/2018 systems, and components (SSCs) must be assured during and after the critical sections within the RXB and CRB. The plots will be supplemented with a discussion of vibratory ground motion associated with the Safe Shutdown Earthquake potential effects of spurious spikes where applicable. The transfer functions will be extracted (SSE) through design, testing, or qualification methods. On Page 3.7-22 of from a sampling of the SSI analyses that have been used for design of the plant:

the FSAR, in the fourth paragraph, the applicant states, However due to the size and complexity of these models it is not practical to review transfer 1. Revise CRB and RXB SSI ISRS calculations to include additional transfer function data at functions at all the nodes in the models. The staff views that the applicant critical node locations.

may not need to review transfer functions (TFs) at all nodes; however, the 2. TFs at those key locations will be reviewed to ensure the adequacy of the SSI models and staff views that TFs at key locations should be reviewed to ensure the methodologies implemented in the seismic analyses.

adequacy of the SSI models and methodologies implemented in the seismic 3. The new plots will be inspected whether spurious spikes in the TFs are present within the analyses. Therefore, the applicant is requested to provide information on TFs frequency range of interest to the SSI analysis; and, if spikes are present, their potential effects (in plots) at selected nodes of the critical sections and other important on computed seismic demands will be investigated to assess whether further refinement or locations in the RXB and CRB. The plots should be inspected whether interpolation steps are necessary.

spurious spikes in the TFs are present within the frequency range of interest to the SSI analysis; and, if spikes are present, the applicant should discuss Tier 2 Section 3.7.2.1.1.3 of the FSAR will be updated to include additional descriptions of the their potential effects on computed seismic demands. transfer functions at critical locations and provide TF plots are critical locations. Any spikes observed in the frequency range of interest will be further explained.

7 8935 03.07.02-26 a. In FSAR Subsection 3.7.2.5.2, the applicant indicates that the ISRS from 1) The ISRS from the triple building model for the design of SSCs in the CRB will be provided. 11/29/2018 the triple building model were considered for the design of SSCs in the RXB ISRS will be developed in accordance with RG. 1.122 "Development of Floor Design Response but not for the CRB. It is expected that the structure-soil-structure interaction Spectra for Seismic Design of Floor-Supported Equipment or Components" and the NuScale (SSSI) effect would be more pronounced on a lighter building (CRB) than a Seismic Design Criteria. FSAR Section 3.7.2 will be updated to include details on the ISRS.

neighboring heavier building (RXB). The applicant is requested to provide justification for not considering the ISRS from the triple building model for the 2) The approach to be used is the same process used for the RXB.

design of SSCs in the CRB.

3) A discussion of the factors contributing to the difference in the RXB ISRS will be provided.

b. Figures 3.7.2-106 and 107 in the FSAR present the Reactor Building ISRS for floor at EL 24 and EL 25, respectively, which indicates noticeable difference in ISRS (both in shape and amplitude) for an elevation difference of only 1 foot. The applicant is requested to discuss the factors contributing to this observed difference.

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LO-1018-62277 NuScale Closure Plan for FSAR Sections 3.7 and 3.8 RAIs - 10/30/2018 Attachment 2 With Interfacing RAI Status Page 6 of 13 eRAI Question# RAI Question Plan Schedule 8 8933 03.07-02-17 10 CFR 50 Appendix S requires that the safety functions of structures, a) Clarification will be provided regarding the foundation differences, and the implication of such 12/20/2018 systems, and components (SSCs) must be assured during and after the on the analytical modeling. FSAR Section 3.7.2 will be updated to state the justification for the vibratory ground motion associated with the Safe Shutdown Earthquake basemat modeling.

(SSE) through design, testing, or qualification methods.

'b) NuScale will provide, through the RAI response, a sensitivity study with summarized results

a. Figure 3.7.2-13 in the FSAR indicates that the refueling area foundation is to support the selection of the large 10e10 lbs/inch stiffness value used for the rigid springs. An lower than the neighboring reactor pool and spent fuel pool area (which is alternate sensitivity study will be presented to justify the use of the rigid springs in the analyses.

also mentioned in the bottom paragraph on Page 3.7-24, indicating a six feet The goal of these rigid springs is to connect the soil nodes to the structural element nodes elevation difference). However, Figure 3.7.2-20 does not indicate these without compromising the soil-structure interaction and building response. Therefore, to differences in foundation elevation. The applicant is requested to clarify demonstrate the validity of the element stiffness, a comparison of relative displacements will be whether these foundation elevation differences are taken into account in the provided between the two nodes of the spring element (I and J) to demonstrate the rigid RXB model; and, if not, please provide justification for not doing so. behavior using the 10e10 lbs/inch stiffness:

b. On Page 3.7-25 of the FSAR, in the sixth paragraph, the applicant states, 1. Using a sampling of SSI analysis cases, extract the relative displacements between the I and The rigid springs have a zero length and have a stiffness value large enough J nodes of the rigid spring elements.

to simulate rigid connection. The large stiffness used is arbitrarily chosen to 2. Clarify that the differential displacement at I and J nodes of rigid link is very small (10-5 in),

be ten billion lbs per inch, or 1010 lbs/inch, in the three global directions. demonstrating rigid behavior.

For the spring to be modeled as a rigid spring, the value of its spring 3. Include results of relative displacements and justification of stiffness in the seismic SSI constant should be sufficiently larger than the stiffness of the structural calculations.

element (basemat) to which it is attached. The applicant is requested to confirm the adequacy of the number (1010 lbs/inch) chosen for the spring Section 3.7.2.1.2.1 will be supplemented to summarize the conclusions of the study and provide constant by comparing it to the stiffness of the adjacent basemat element or technical justification confirming the 10e10 lbs/inch stiffness property simulates a rigid through an appropriate sensitivity run using a number at least an order of connection.

magnitude different.

c. In Table 3.7.2-1 in the FSAR, the maximum aspect ratio for RXB finite c) All finite elements used were within the bounds of the V&V of the software. Some larger elements is indicated as 11.9. The applicant is requested to ensure that this elements were used as a way to apply surface loads to the structure, and these elements tend to value of aspect ratio is within the range of the parameters covered in the have larger aspect ratios. However, much smaller elements were used for the dynamic SASSI V&V; if not, provide justification for the adequacy of using the characteristics of the structure.

maximum aspect ratio of 11.9 for RXB finite elements.

9 8935 03.07.02-25 10 CFR 50 Appendix S requires that the safety functions of structures, 1) Provide the design-basis seismic demands, at all applicable critical section locations of the 12/20/2018 systems, and components (SSCs) must be assured during and after the RXB and CRB. The forces, displacements, soil pressures, and ISRS will be computed according vibratory ground motion associated with the Safe Shutdown Earthquake to NRC RG's, SRP's and DSRS (using the approaches outlined in FSAR Section 3.8.4 and (SSE) through design, testing, or qualification methods. 3.8.5). ACI 349-06 provides acceptance criteria for displacements in concrete structures.

Tables 3.7.2-23, 24 and 25 in the FSAR respectively provide SSI analysis results for one particular example shell, beam, and solid element, 2) Tables 3.7.2-23, 24 and 25 will be revised or a new table will be provided.

respectively. However, analysis results at other key locations are not provided. The applicant is requested to provide the design-basis seismic demands (e.g., forces, moments, soil pressures, accelerations, displacements, ISRS), at all applicable critical section locations of the RXB and CRB, that are used in structural design evaluations in FSAR Sections 3.8.4 and 3.8.5.

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LO-1018-62277 NuScale Closure Plan for FSAR Sections 3.7 and 3.8 RAIs - 10/30/2018 Attachment 2 With Interfacing RAI Status Page 7 of 13 eRAI Question# RAI Question Plan Schedule 10 8963 03.08.05-6 Section 3.8.4.1, the basemat reinforcement pattern of the foundation of NuScale will provide, through the RAI response, additional information to supplement the design 12/20/2018 RXB. However, the applicant did not provide sufficient information for the of the RXB and CRB basemat. The information will be tabulated to support design assessments, design assessments, boundary conditions for each foundation model, and will include design capacity, forces and moments at critical sections. In addition, a full settlement evaluation and associated figures. Provide for the RXB basemat: description of analysis and boundary conditions will be provided for each model to demonstrate

- design assessments-should include: the capacity of sections, design compliance with DSRS Section 3.8.5.II.4.N. To support the response:

checks, etc.

- boundary conditions for each foundation model -should include: stiffness 1. Triple Building Differential Settlement calculation will be revised to include the capacity of types and parameter throughout the embedded portion of the RXB for each sections, forces & moments at critical locations, settlement evaluation, and additional boundary type of model (standalone and combined) - SASSI2010, SAP2000, and conditions.

ANSYS -- 2. The additional informaiton will be reviewed, organized and tabulated to support design

- settlement evaluations and figures showing reinforcement patters for (a) the assessments.

entire RXB basemat, (b) intersections between walls & the RXB basemat, and (c) intersections between pilasters & the RXB basemat. Settlement Tier 2 Section 3.8.5.4.1 of the FSAR will be supplemented with additional descriptions of the evaluation should include following types of settlements: (1) Maximum basemat foundation analyses including boundary conditions and settlement evaluations. The vertical settlements, (2) tilt settlement, (3) differential settlement between additional information provided in tabular format for the design assessments of the foundations structures and (4) angular distortion. will be added to Appendix 3B of the FSAR.

11 8971 03.08.04-11 While the magnitude of bounding demand forces and moments were Critical sections are defined as parts of the structure that: (1) perform a safety-critical function, 12/20/2018 provided for some critical sections (e.g. FSAR Tables 3B-36 to 3B-38), the (2) are subjected to large stress demands, (3) are considered difficult to design or construct, or FSAR did not provide the magnitudes of bounding demand forces and (4) are considered to be representative of the structural design. These critical sections are listed moments for all critical sections identified for the RXB and CRB. Provide in in Appendix 3B of the FSAR. Static and dynamic structural responses obtained from SAP2000 the FSAR the magnitude of bounding demand forces and moments for all and SASSI2010 analyses will be have been utilized to develop demand forces and moments critical sections, with a breakdown of seismic and static forces and moments. such as static compression (negative) or tension (positive) membrane forces for walls and slabs.

Results of the SASSI2010 soil-structure interaction analysis which is used to analyze seismic Additionally, provide a numerical example that demonstrates how the loads will contain dynamic force and moments which are dependent of the direction of the direction of dynamic forces and moments is addressed in the load seismic load applied to the structure. The direction resulting in most adverse load combination is combinations as to ensure that the direction that is most adverse in a load considered for structural design. The presentation in the already completed calculations will be combination has been considered as indicated in FSAR Section 3B.1.1.2. revised to more clearly show the magnitudes of bounding demand forces and moments for all critical sections.

To show how the effect of the direction of the seismic loads is considered in the design, an example will be provided that demonstrates that the most adverse direction in a load combination has been considered. In addition, a breakdown of static and seismic forces will be prepared and presented. Finally, FSAR Section 3.8.4 and Appendix 3B will be revised to include the details of the above research.

In summary,

1) Revise the calculations to include the magnitudes of bounding demand forces and moments for all critical sections;

2) Include a breakdown of seismic and static forces and moments;

3) Develop an example to demonstrate that the most adverse direction in a load combination has been considered; and

4) Update the FSAR Section 3.8.4 and Appendix 3B and include the results of the above research.

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LO-1018-62277 NuScale Closure Plan for FSAR Sections 3.7 and 3.8 RAIs - 10/30/2018 Attachment 2 With Interfacing RAI Status Page 8 of 13 eRAI Question# RAI Question Plan Schedule 12 8974 03.08.04-20 10 CFR 50, Appendix A, GDC 1, 2, and 4 provides requirements to be met 1) The magnitude of bounding seismic design forces of the roof in the three orthogonal 12/20/2018 by SSC important to safety. In accordance with these requirements, DSRS directions will be provided, consistent with DSRS Section 3.8.4.

Section 3.8.4 provides review guidance pertaining to the design of important The following approach will be taken to address the response:

to safety seismic Category I structures, other than the containment. - Revise the already completed calculations for RXB SSI and CRB SSI to more clearly Consistent with DSRS Section 3.8.4, the staff reviews, in part, loads and present the magnitude of bounding seismic design forces of the roof in the three loading combinations. orthogonal directions.

Provide the magnitude of bounding seismic design forces of the roof in the - A table, showing the bounding forces, will be added to FSAR Section 3.8.4 three orthogonal directions (North-South, East-West, and Vertical).

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LO-1018-62277 NuScale Closure Plan for FSAR Sections 3.7 and 3.8 RAIs - 10/30/2018 Attachment 2 With Interfacing RAI Status Page 9 of 13 eRAI Question# RAI Question Plan Schedule 13 8911 03.09.02-43 TR-0916-51502-P, Rev. 0, Section 8.4.3 states that maximum uplift NuScale will perform new seismic runs including the cases requested in this RAI. In addition, 12/21/2018 displacements of the NPM were calculated for each of the six analysis runs. NuScale will rerun the cases already provided. All new runs incorporate an enhanced The maximum uplift occurred in the run representing the Capitola time methodology for modeling hydrodynamic mass in the pool area; this modeling uses harmonic history, soil type 7, with cracked RXB concrete, on the NPM in operating bay analysis, modal analysis, and hand calculations to determine the hydrodynamic loading for the 6 with a nominal stiffness. As stated in Section 8.0, for the cracked RXB bay walls, walls in the refueling area, and the pool walls and floor, respectively. The new concrete case, two NPM stiffness were considered. Section 7.4 of the report hydrodynamic mass along with the 12 detailed NPM beam models have been incorporated into states that uncertainty in the input and assumptions used in the finite the RXB SAP2000 model, and subsequently the cracked and uncraked RXB SASSI models. The element models of the NPM is accounted for by considering multiple updated SASSI models have been run with Soil Type 7, at 4% structural damping using the analyses using +/-30 percent variations of the stiffness properties of the CSDRS compatible-Capitola time history to generate in-structure time histories in the pool area model. Therefore, in calculation of the maximum NPM uplift, the NRC staff and RXB ISRS. Those time histories are used for NPM anlaysis. The complete set analysis results considers that the case of 130% of the NPM stiffness for the cracked RXB will be used to revise the seismic technical report.

concrete case should be considered. Increasing the NPM stiffness may bring the NPM dominant frequency closer to the cracked RXB frequency. The In addition, ISRS for select locations in the RXB will be developed and checked against previously results of 77% NPM stiffness could be non-conservative. The applicant is developed RXB ISRS in the FSAR. Any ISRS exceedances will be incorporated and will be requested to provide the maximum NPM uplift in the cracked RXB concrete revised in the FSAR. SASSI runs will also be made with Soil Type 7, at 7% concrete damping case with an adjustment of +30 percent variation of the NPM stiffness (i.e., using the CSDRS compatible-Capitola time history to develop forces and moments, and those too 130% NPM stiffness). Alternatively, provide justification for not performing a will be checked against previously calculated demand.

cracked RXB concrete case with 130% of the NPM stiffness. Include the requested information in the NPM Seismic Report or in separate reports. The response will be provided by the specified due date.

NRC feedback, received 10/23, will be addressed in the RAI response, except for the comparison of the RFT support loads. The following items will be addressed:

1. Listing the six SASSI analysis cases that are used in the NPM seismic analysis.

2. Description of the enhanced method of modeling the hydrodynamic mass and determining the hydrodynamic load for bay walls, walls in the refueling area, pool walls and floor.

3. Comparison of the NPM support loads obtained from the new analyses (SASSI and ANSYS 3D NPM) with the corresponding support loads used for the design of the NPM supports.

4. Comparison of the hydrodynamic pressures obtained from the new analyses (SASSI and ANSYS 3D NPM) with the corresponding pressure loads used for the design of the pool walls and floor.

5. The final response spectra corresponding to the seismic input for the NPM seismic analysis (including the case when the lower RPV is in the RFT)

6. Updating FSAR markups pertaining to Sections 3.7 and 3.8 that are impacted by new or re-analyses performed under this Closure Plan.

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LO-1018-62277 NuScale Closure Plan for FSAR Sections 3.7 and 3.8 RAIs - 10/30/2018 Attachment 2 With Interfacing RAI Status Page 10 of 13 eRAI Question# RAI Question Plan Schedule 14 8911 03.09.02-45 TR-0916-51502-P, Rev. 0, Appendix C, Table C-1 (Summary of NuScale Reflector Blocks/Lower Core Plate design 12/21/2018 Power Module Component Interfaces) states that the reflector blocks and lower core plate are stacked and restrained in the horizontal direction with Appendix C has been removed in TR-0916-51502-P, Rev. 1 alignment pins. The reflector blocks and lower core plate are not restrained in the vertical direction other than by gravity. Tolerances and deformation 1. In the NPM detailed 3D ANSYS model used for time history analysis, the reflector blocks have between the mating parts allow some sliding to take place between parts. On been modeled separate from the rest of the lower RVI. This model accounts for potential uplift, the interface between the upper riser and lower riser, Table C-1 states that and will be was documented in the upcoming release with the recent submittal of TR-0916-51502 the lower riser conical section seats within the upper riser conical section. Revision 1 (NuScale letter LO-0918-61887, September 28, 2018). The maximum uplift between There are tolerances between the two interfacing components allowing them the 1st block and the lower core plate was determined to be ((2(a),(c) (TR Table 8-9). This to pitch slightly. The upper riser is not restrained in the vertical direction other amount of uplift (and associated calculated impact force of (( }}2(a),(c) (TR Table 8-8) produces than by gravity and compression of the bellows which keeps the interface an increased vertical response spectrum for the lower core plate in the range from (( }}2(a),(c) closed. The description is insufficient for staff to reach a safety finding. The (TR Figure B-21). Following the upcoming revision to the seismic input motions (which account applicant is requested to provide the following information: for changes to the hydrodynamic mass applied to the pool walls, and are planned to be

1. Figure B-18 (vertical ISRS at top of the lower core plate) indicates that the documented in TR-0916-51502 Revision 2) the impact of the change on the fuel will be evaluated maximum vertical acceleration at top of the lower core plate is about 1.6 g to determine if the fuel is still bounded by existing margins or the scope of work required to (i.e., spectral acceleration at the high frequency end of the ISRS) that establish new margins.

exceeds gravity acceleration. Provide a discussion on the possibility of uplift between the reflector blocks as well as between the reflector blocks and the 2. In the NPM detailed 3D ANSYS model, the upper and lower risers are not coupled in the lower core plate under the maximum vertical acceleration and their vertical direction. The maximum relative displacement between the upper and lower risers is consequence. captured by the outputs of the NPM detailed 3D ANSYS transient analysis, and is are currently

2. Provide the vertical ISRS and the maximum vertical acceleration at the taken as (( }}2(a),(c). After the analysis is redone with the new seismic input motions that interface between the upper riser and the lower riser. Provide a discussion account for changes to the hydrodynamic mass applied to the pool walls, uplift of the upper riser on the possibility of uplift of the upper riser from the lower riser under the from the lower riser will be shown to be negligible using a hand calculation for the impact force of maximum vertical acceleration and their consequence. the upper riser on the lower riser given the maximum relative displacement between the two.

Include the requested information in the NPM Seismic Report. Alternatively, provide testing data to justify the use of 7% damping for RVI, RPV, containment, and NPM system damping or add an ITAAC to measure the as-built RVI components, RPV, containment, and NuScale power module system damping. Include the requested information in the NPM Seismic Report. NuScale Nonproprietary Page 10 of 13

LO-1018-62277 NuScale Closure Plan for FSAR Sections 3.7 and 3.8 RAIs - 10/30/2018 Attachment 2 With Interfacing RAI Status Page 11 of 13 eRAI Question# RAI Question Plan Schedule 15 9225 04.02-8 In RAI 8769 Question 1, the staff requested information regarding fuel eRAI 9225 will provide core plate accelerations in the RFT after completion of new analysis. 4/26/2019 assembly structural response when in approved locations outside of an operating bay. As part of its response to this question, NuScale provided a RAI 9225 requires analysis of the fuel in the RFT. The seismic analysis of the NuScale Power Table which compared upper core plate motions when the fuel is located in Module (NPM) is being re-performed this fall and is expected to complete by December 14th, the RFT as compared with the motions when the fuel was located in an 2018 October 26, 2018. The analysis will define core plate motions that will be ready for operating bay. While the results indicate that the upper core plate motions in Framatome to evaluate for impact on the fuel by November 28th. If the core plate motion results an operating bay bound those found when the fuel is located in the RFT, the are bounded by the current fuel seismic analysis of record, FRAMATOME will not need to perform staff notes that the RFT design is not currently finalized, as indicated by staff a re-analysis of the fuel. In this scenario, the response to RAI 9225 could be submitted in early RAI 8838. Therefore, the staff does not consider Table 1 of the response to January of 2019. The schedule for 9225 has been developed assuming the seismic results are not RAI 8769 Question 1 to be final. bounded, would result in Framatome performing a fuel analysis that would take about 4 months to complete. Update the core plate motions provided in the response to RAI 8769 Question 1 Table 1 with values derived from a final RFT design, or provide justification to explain how the values presented are bounding for all potential RFT designs. NuScale Nonproprietary Page 11 of 13

LO-1018-62277 NuScale Closure Plan for FSAR Sections 3.7 and 3.8 RAIs - 10/30/2018 Attachment 2 With Interfacing RAI Status Page 12 of 13 eRAI Question# RAI Question Plan Schedule 16 8838 03.08.04-1 Title 10 of the Code of Federal Regulations, Part 50, Appendix A, Criterion Initial response submitted 7/5/2018 November requires, in part, that SSCs important to safety are designed to withstand the 2018 effects of earthquakes without the loss of capability to perform their safety Errors have been identified, by NuScale, in both the seismic analysis and stress analysis of the functions. The design bases for these SSCs shall reflect: (1) the severity of RFT. The errors relate to boundary conditions used in both of the analyses, and the magnitude of the historical reports, with sufficient margin to cover the limited accuracy, the applied seismic load in the stress analysis. NuScale has started to evaulate alternate designs quantity, and time period for the accumulated data, (2) appropriate required to resolve the RFT design issues. The supplemental RAI response that discusses the combinations of the effects of normal and accident conditions with the effects RFT analysis will be delayed until the issues are resolved. NuScale will provide NRC a closure of the natural phenomena, and (3) the importance of the safety functions to plan for this issue in November 2018. be performed. DSRS Sections 3.7.2 and 3.8.4 provide review guidance pertaining to the seismic analysis, including interaction of the nonseismic Category I structures with seismic Category I SSCs, and structural design, including consideration of seismic loads, respectively. FSAR Section 9.1.5.2.3 describes refueling operations including, in part: (1) the placement and restraining of a bioshield on an adjacent bioshield; (2) the use of a containment vessel (CNV) flange tool (CFT) and reactor vessel (RPV) flange tool (RFT) for de- tensioning flange closure bolts and as structural supports during refueling operations; and (3) the placement of the upper CNV with the upper RPV still attached on the module inspection rack in the flooded dry dock. To assist the staff in evaluating the compliance of the aforementioned components with the above regulatory requirements the staff request the applicant to provide the following information and include these information in the FSAR (Sections 3.7 and 3.8, as applicable). Describe the method/mechanism for restraining a bioshield mounted on an adjacent bioshield and restraining the upper CNV on the module inspection rack during the refueling operations. Further, provide analysis and design criteria (consistent with DSRS Section 3.7.2.II.8) to ensure no adverse interactions occur between the seismic Category II bioshields and inspection racks with adjacent seismic Category I SSCs, during refueling operations (and during the transport of new modules, as applicable). For the seismic Category II CFT, a description of the CFT geometry, weight (with and without the lower CNV), structural materials, separation distance between the CFT and the RFT and surrounding walls, connection to the basemat, and analysis and design criteria (consistent with DSRS Section 3.7.2.II.8) to ensure no adverse interactions occur between the CFT and adjacent seismic Category I SSCs during refueling operations. For the seismic Category I RFT, design information including geometry, weight (with and without the RPV lower head), separation distance between RFT and surrounding walls, connection to the basemat, applicable design codes, standards, and specifications, design and analysis procedures, structural acceptance criteria, materials, quality control, special construction techniques (as applicable) and quality assurance requirements, testing and inservice surveillance programs, and ITAAC (as applicable). NuScale Nonproprietary Page 12 of 13

LO-1018-62277 NuScale Closure Plan for FSAR Sections 3.7 and 3.8 RAIs - 10/30/2018 Attachment 2 With Interfacing RAI Status Page 13 of 13 eRAI Question# RAI Question Plan Schedule 8838 Further, provide the seismic input (ISRS and acceleration time histories) at cont. the base of the RFT, and at lower and upper core plate (if any) elevations while mounted on the RFT. Additionally, provide a description of how the seismic input motion is transferred from the RFT base elevation to the lower and upper core plate (if any) elevations. NRC Feedback: With respect to the CFT, the response indicates that design specifications have been prepared that establish the design criteria for the SC II CFT that address II/I design requirements. The staff request the applicant to provide a summary in the FSAR addressing the design criteria and II/I requirements for the CFT. With respect to the RFT, clarify whether the structural acceptance criteria for the RFT stand is also applicable to the embedded plate or if different, provide the structural acceptance criteria for the embedded plate. Further, clarify whether the embedded plate is made of 304L stainless steel or if different, indicate the embedded plate material. Describe how the embedded plate is anchored to the pool basemat. Describe the specific loads and load combinations used in the analysis and design of the RFT tool. Describe the seismic analysis case (s) considered in the analysis and design of the RFT. Describe the type of analysis performed (e.g. static, dynamic - response spectrum or time history analysis), analysis software used, and input properties such as damping, cracked/uncrack concrete properties (if any), as applicable. Update FSAR markups, as necessary to address the above information. Provide a summary of results for the RFT stand and embedded plate in the FSAR such as demand, capacity/allowable limits, and associated demand over capacity ratios. Provide FSAR figures addressing the RFT stand and embedded plate analysis model and RFT stand and embedded plate design including dimensions (e.g. plates, bolts, welds, concrete anchors, etc) and materials. Also, address the RFT analysis case (s) in FSAR Tables 3.7.2-34 and 3.7.2-35. Further, clarify whether the RFT is covered in the RXB ITAAC or other ITAAC, as applicable. Additionally, clarify how the weights associated with both the RFT and CFT have been considered in the analysis/design of the RXB basemat. NuScale Nonproprietary Page 13 of 13

LO-1018-62277 : Affidavit of Zackary W. Rad, AF-1018-62347 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 Zackary W. Rad I, Zackary W. Rad, 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 report reveals distinguishing aspects about the NuScale Power Module seismic analysis. NuScale has performed significant research and evaluation to develop this analysis 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, NuScale's 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 NuScale's 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 report entitled NuScale Closure Plan for FSAR Sections 3.7 and 3.8 RAIs. 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. (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 AF-1018-62347 Page 1 of 2

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 Nu Scale, 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 Nu Scale's 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 Nu Scale 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 October 29, 2018. AF-1018-62347 Page 2 of 2}}