ML21132A295

Summary of Public Meeting to Discuss Technology Inclusive Content of Application Project

ML21132A295
Person / Time
Site:	Grand Gulf, Arkansas Nuclear, River Bend, Waterford
Issue date:	05/14/2021
From:	Joseph Sebrosky NRC/NRR/DANU/UARP
To:	John Segala NRC/NRR/DANU/UARP
Sebrosky J
References
Download: ML21132A295 (19)

Text

J. Segala 1

May 14, 2021 MEMORANDUM TO:

John P. Segala, Chief Advanced Reactor Policy Branch Division of Advanced Reactors and Non-Power Production and Utilization Facilities Office of Nuclear Reactor Regulation FROM:

Joseph M. Sebrosky, Senior Project Manager Division of Advanced Reactors and Non-Power Production and Utilization Facilities Office of Nuclear Reactor Regulation

SUMMARY

OF MAY 11, 2021, PUBLIC MEETING TO DISCUSS TECHNOLOGY INCLUSIVE CONTENT OF APPLICATION PROJECT On May 11, 2021, the U.S. Nuclear Regulatory Commission (NRC) staff held a public meeting with stakeholders, to discuss the technology inclusive content of application project (TICAP).

The meeting notice is available in the NRCs Agencywide Documents Access and Management System (ADAMS) at Accession No. ML21131A027, and the presentation slides are available at ADAMS Accession No. ML21130A649. The Enclosure 1 to this summary provides the attendees for the meeting as captured by Microsoft Teams.

Meeting Highlights The meeting was in the form of a workshop. The purpose of the workshop was to discuss industrys draft TICAP guidance document found at ADAMS Accession No. ML21106A013. Prior to the workshop the NRC staff identified a list of 23 items that were identified as topics to be discussed during this workshop and TICAP workshops tentatively scheduled for May 19, 2021, and May 26, 2021. The list of issues can be found at ADAMS Accession No. ML21120A057. Thirteen of the 23 items were discussed during the May 11, 2021 workshop. A path forward for the majority of the issues discussed during workshop was identified. Enclosure 2 documents the results of the workshop in the disposition column.

There were three areas that were identified for further discussion. These areas included:

Topic 9, reliability and capability targets, from the list found in Enclosure 2. This issue was originally identified as an outcome of the TICAP tabletop exercises that were held in the February through March 2021 time frame. The observations from these TICAP tabletop exercises can be found at ADAMS Accession No. ML21125A139.

CONTACT: Joseph Sebrosky NRR/DANU 301-4151132 Signed by Sebrosky, Jose on 05/14/21

J. Segala 2

The NRC staff noted that industrys draft TICAP guidance document does not appear to be consistent with NEI 18-04, Rev 1, Risk-Informed Performance-Based Technology Guidance for Non-Light Water Reactors, (ADAMS Accession No. ML19241A336) in that the reliability and capability targets are not proposed to be captured in the safety analysis report (SAR). From the staffs perspective the SAR should describe reliability targets and performance requirements used as input to the probabilistic risk assessment and for structures, systems and components that were used to develop the selection of special treatment requirements (i.e., programmatic actions used to maintain performance within the design reliability targets). The staff noted this information is important to capture in the SAR and in some cases could also be captured as part of technical specification requirements. From the industrys perspective, there is a concern that placing such information in the SAR is unnecessary and would potentially create a burden from a change control process standpoint. The staff and industry agreed to discuss this issue further in a future TICAP workshop.

Topics 10 and 12 from the list found in Enclosure 2 associated with level of defense-in-depth information provided in the SAR This issue was also identified as a result of the TICAP tabletop exercises. The staff noted that NEI 18-04 provides important defense-in-depth considerations that the staff noted should be captured in the SAR. Industry believes only the results should be captured in the SAR. The staff took an action to provide examples of documentation that would be expected to be captured in the SAR based on the guidance in NEI 18-04. These examples will be provided to industry and discussed at an upcoming workshop.

Topic 20 from the list found in Enclosure 2 associated with the scope of industrys TICAP guidance and where guidance such as fuel qualification, ASME Section III Division 5, instrumentation and control design review guide, and siting will be found. Industrys TICAP guidance is focused on the first 8 chapters of the SAR and applies NEI 18-04 concepts to these chapters. The staff noted that important information such as siting would be expected to be found in the first 8 chapters of the SAR and that supplemental guidance for siting should be provided. The staff took an action to provide white papers on drafts of a TICAP regulatory guide and an Advanced Reactor Content of Application Project roadmap interim staff guidance that preliminarily provides pointers on how industrys TICAP guidance could be supplemented based on important guidance that the staff is developing.

At the end of the workshop the staff noted the dates for the upcoming workshops and the target date of early June 2021 for the NRC staff to provide a complete set of comments on the industrys draft TICAP guidance document and industrys target of late July for providing a revision to the document. The staff noted that the list provided in Enclosure 2 are the high-level issues associated with industrys draft guidance document. The staff informed industry that it was also developing comments embedded within the draft document that did not rise to a level to be discussed during the workshops. The staff took an action to provide a list of these more detailed comments prior to the last workshop such that if industry had questions associated with these comments those questions could be addressed during one of the two remaining workshops.

Enclosure:

1.

Attendance List 2.

List of Topics of Discussion for TICAP Workshops

ML21132A295 NRC-001 OFFICE NRR/DANU/UARP/PM NRR/DANU/UARP/BC NRR/DANU/UARP/PM NAME JSebrosky JSegala JSebrosky DATE 5/12/2021 5/14/2021 5/14/2021 May 11, 2021, Public Meeting to Discuss Technology Inclusive Content of Application Project Attendance List*

NAME AFFILIATION NAME AFFILIATION Nathan Sanfilippo NRC/NRR/DANU Amir Afzali Southern Company Martin Stutzke NRC/NRR/DANU Jason Redd Southern Nuclear Dayna Dority NRC/NRR/DANU Brandon Chisholm John Segala NRC/NRR/DANU/UARP Mike Tschiltz NEI Prosanta Chowdhury NRC/NRR/DANU/UARP Cyril Draffin US Nuclear Industry Council Maryam Khan NRC/NRR/DANU/UARP George Flanagan Oak Ridge National Lab Eric Oesterle NRC/NRR/DANU/UARP Ed Wallace GNBC Associates Arlon Costa NRC/NRR/DANU/UARP Steven Nesbit LMNT Consulting Juan Uribe NRC/NRR/DANU/UARP Frank Akstulewicz A to Z Reactor Consulting Services Amy Cubbage NRC/NRR/DANU/UARP Steve Vaughn X-energy Joe Sebrosky NRC/NRR/DANU/UARP Travis Chapman X-Energy Nan Valliere NRC/NRR/DANU/UARP Jim Kinsey Idaho National Laboratory (INL)

Jordan Hoellman NRC/NRR/DANU/UARP Tom King INL Stephen Philpott NRC/NRR/DANU/UARP Christopher Chwasz INL Dawnmathews Kalathiveettil NRC/NRR/DANU/UARP Tom Hicks INL Margaret OBanion NRC/NRR/DANU/UARP Ricardo Davis-Zapata GE Power Adrian Muniz NRC/NRR/DANU/UARL Dennis Henneke GE Power Mallecia Sutton NRC/NRR/DANU/UARL George Wadkins GE Power Lucieann Vechioli Feliciano NRC/NRR/DANU/UARL Archana Manoharan Not Available (NA)

Alexandra Siwy NRC/NRR/DANU/UARL Farshid Shahrokhi NA Michelle Hayes NRC/NRR/DANU/UART Lance Sterling NA Michelle Hart NRC/NRR/DANU/UART Bill Fowler NA Timothy Lupold NRC/NRR/DANU/UART Michael Mayfield NA Ian Jung NRC/NRR/DANU/UART Alan Levin NA Chris Van Wert NRC/NRR/DANU/UART Tom Braudt NA Boyce Travis NRC/NRR/DANU/UART Karl Fleming NA Tim Drzewiecki NRC/NRR/DANU/UART Jana Bergman NA Tony Nakanishi NRC/COMM/OCM Rob Burg NA Eric Bowman NRC/COMM/CS Barton Landon Pate NA Rao Tammara NRR/DEX/EXHB Jeremy Shook NA Susan Vrahoretis NRC/OGC Narasimha Kadambi NA Marcia Carpentier NRC/OGC Maxwell Smith NA Derek Widmayer NRC/ACRS Parthasarathy Chandran NA Raul Hernadez NRR/DSS/SCPB Robert Sweeney NA Scott Bussey NRC/OCHCO/ADHRTD/

RTTB Maxine Keefe NA

2 NAME AFFILIATION NAME AFFILIATION Donald Palmrose NRC/NMSS/REFS/ERNRB Douglass Miller NA Andrew Zach EPW Anthony Schoedel NA Lisa Matis NA Adam Stein NA Chantal Morin NA

• Attendance list based on Microsoft Teams Participant list. List does not include 9 individuals that connected via phone.

List of Topics of Discussion for Technology Inclusive Content of Application Project Workshops Issue Topic Priority Comments Disposition 1

The construction permit (CP) guidance contained in the two-step Licensing section is not sufficiently detailed to ensure consistent implementation.

Hi For Sections 1.2, 1.3, 1.4, 2.4 there is no CP guidance. For Section 2.3, simplified and/or qualitative analyses should be available to support reasonable assurance findings (examples are provided in Appendix C of NRCs Construction Permit White Paper found at ADAMS Accession No. ML21043A339)

Chapter 3 - Use of term preliminary assessments. What does that mean?

Should reference bounding assumptions and conservative modeling to account for the uncertainty in final design details. Should reference discussion of the major SSCs of the facility that are intended to mitigate the radiological consequences of a design basis accident (DBA).

For Chapter 4, the staff would like to understand better the use of term preliminary description of the integrated plant performance.

For Chapter 6, guidance for first of a kind (FOAK) structures, systems and components (SSCs) does not appear to be sufficiently detailed to ensure consistent implementation.

The CP guidance should consider including a description of the research and development (R&D) plans supporting the design.

The minimum level of detail to support a CP application should be considered for discussion. The CP white paper provides thoughts regarding minimum level of detail.

The non-light water reactor probabilistic risk assessment (NLWR PRA) standard (ASME/ANS RA-S-1-4-2021) contains numerous supporting requirements to document the assumptions made in lieu of detailed design information. Will these assumptions be identified in the preliminary safety analysis report (PSAR) or will they be provided in the detailed PRA information (which is only available to the staff via an onsite audit)? This comment is related to Issue #8 below.

Proposed for Workshop #1 discussion

2 Issue Topic Priority Comments Disposition The staff expects that the TICAP guidance document will be used to support near-term non-LWR CP applications. Discussions of how the TICAP guidance document might be used along with preapplication discussions to aid the near-term reviews could be a topic of a workshop. Such an approach could potentially be used to develop near-term guidance with revised updated guidance being issued at a later date. The revised guidance could be based on lessons learned from the initial construction permit reviews.

2 Source term guidance might need to be expanded.

Med The source term discussion should require the attenuation mechanisms be described. These are just as important in limiting radionuclide release as is fuel performance.

Source terms should be detailed for each licensing basis event (LBE), but no confirmatory analyses is done to ensure inclusion of all source terms.

Workshop #1 TICAP to clarify in guidance that attenuation mechanisms are to be described.

3 The guidance in several areas is too general to ensure consistent and adequate implementation, such as the use of terms like relevant phenomena, initial operating conditions, and identify treatments.

Additional examples in this area are provided in items 3a through 3d below.

Workshop #1 TICAP acknowledges that some guidance can be made more specific but there are limitations on how specific for technology inclusive guidance.

NRC to provide additional examples as part of written comments.

3a The guidance should be more specific in specifying initial plant parameters, settings of protection system functions, meteorological assumptions, uncertainty assumptions, and characteristics of fission product releases assumed in the LBE analysis.

For modular nuclear power reactor design; describe and analyze the possible operating configurations of the reactor modules with common systems, interface requirements, and system interactions.

TICAP believes multiple modules are addressed in LBE descriptions (Chapter 3) and interface requirements and system interactions are addressed in system descriptions (Chapters 6 and 7). However, TICAP will review the current wording to see if enhancements are warranted.

3 Issue Topic Priority Comments Disposition 3b The guidance regarding the defense in depth (DID) content should be expanded to address the areas discussed in the staffs April 2020 annotated outline in Chapter 7 (see:

ADAMS Accession No. ML20107J565) which were derived from NEI 18-04 Section 4.2 (DID) states that the scope and content of the final safety analysis report (FSAR) are focused on presenting results, not details of the process. It goes on to say that the topics to be addressed in the evaluation of DID are for background and there is no requirement to address each topic in the FSAR. Why isnt discussion of the evaluation topics important enough to be placed in the FSAR? This provides the technical basis for the DID adequacy determination.

Other sections (4.2.1, 5.4) make similar statements with no basis.

NEI 18-04 (Section 5.9.3) states that the adequacy of DID is confirmed when the actions and decisions (listed in 5.9.3) are completed by the Integrated Decision-Making Process (IDP). There is hardly any mention of the IDP in the TICAP guidance, yet NEI 18-04 emphasizes it.

Section 5.4 (Safety-Related SSCs) states in the introduction that in identifying safety-related SSCs, the SSCs not selected as safety-related constitute one element of Plant Capability DID. However, the introduction goes on to say that these DID SSCs are not design basis information. Why aren't DID SSCs in the design basis? What is the basis for excluding the information used to select the safety-related SSCs from the SAR?"

TICAP discussed desire to focus SAR content on results rather than process.

NRC to provide specific recommendations where additional DID content is desired in the SAR, along with the rationale.

3c In addressing the special treatments the guidance should specify that the application address the special treatment requirements from NEI 18-04, Table 4-1, on a case-by-case basis and in the context of the SSC functions in the prevention and mitigation of applicable LBEs.

Describe safety related (SR) SSC reliability targets and performance requirements used as input to the PRA for SSCs that were used to develop the selection of special treatment requirements (i.e., programmatic actions used to maintain performance within the design reliability targets).

Guidance should point to NEI 18-04 Table 4-1 and have the applicant address the items in that list:

(from NEI 18-04, Table 4-1, as applicable)

i. Equipment qualification ii. Seismic qualification iii. Materials qualification iv. Pre-service and risk-informed in-service inspections

v. Pre-op and startup testing requirements vi. Surveillance testing requirements TICAP will enhance the linkages between special treatments in Chapters 6 and 7 and the programs in Chapter 8.

TICAP stated that the SAR content for the LMP-based affirmative safety case should focus of the special treatments that were selected through the LMP process, vs.

documenting why special treatments were not selected.

4 Issue Topic Priority Comments Disposition 3d Similarly, guidance discussion of "optional" programs should instead make a clearer tie between identified special treatments and the programs that implement those treatments The programmatic actions used to maintain performance within the design reliability targets should include a description of how actual SSC reliability is determined and compared against the design reliability target (e.g., as part of the Maintenance Rule program).

TICAP will revisit the linkages between special treatments and programs (see 3c).

NRC clarified that optional refers to whether or not the special treatment invoking the program was selected.

4 The guidance references the modular high temperature gas cooled reactor preliminary safety information document (PSID) as guidance but does not reference the staffs safety evaluation report on that PSID which identified gaps in necessary content.

Discuss whether actual guidance that is referenced should be placed in the TICAP guidance document instead of referencing the document Hi An example discussion from the staffs safety evaluation found at ADAMS Accession No. ML052780497 is as follows:

Some events were not defined explicitly enough to quantify properly.

Common-mode and common-cause events were not present explicitly in the models. Human failure events were too vaguely described to determine whether they were assumed to occur before the event initiation or afterMost restrictive in tracing the results of the PRA was the fact that there is no list of basic events that includes the occurrence probability associated with each event.

Workshop #1 The PSID references were for the purposes of guidance documentation only; the safety evaluation is therefore not relevant to the guidance.

TICAP will revisit the PSID examples to update them or, if necessary, replace them with TICAP examples.

TICAP will endeavor to include the examples directly in the guidance rather than referencing them.

5 Issue Topic Priority Comments Disposition 5

The document describes a move away from compliance-based applications to a more performance-based approach.

It's not clear from these statements whether applicants will be expected to describe how they comply with the regulations that are associated with the performance-based scope and outcomes of the affirmative safety case approach. regulations is an expectation for application content.

Hi The TICAP guidance does not require the NRC regulations applicable to the design be identified or discussed. Isnt the purpose of the FSAR to demonstrate compliance with the applicable regulations?

LMP primarily addresses the 50.34 requirements to identify events, plant response to those events, and associated safety margins. This provides an alternative to the LWR-based regulations that directly connect to this part of 50.34 (50.46 requirements for ECCS, for example). Is this the basic population of regulations industry is referring to in its proposed change from compliance-based?

Does the content of this TICAP guidance align with the NRCs regulatory applicability assessments in NRC Staff Draft White Paper - Analysis of Applicability of NRC Regulations for Non-Light Water Reactors, as discussed in recent non-LWR stakeholder meetings?

Potentially another way to consider the affirmative safety case approach is stated in RG 1.233 as safety evaluations may demonstrate compliance with or justify exemptions from specific NRC regulations and identify where design-specific regulatory controls are warranted. An application will need to address the results from the safety case in terms of where current regulations do not contribute to safety (exemptions) or where current regulations are lacking (additional requirements). Whereas the safety case should focus on satisfying subject functions, it would be useful to agree on a format for compliance/exemption discussions, be they embedded, in a table, or other format.

Workshop #2

6 Issue Topic Priority Comments Disposition 6

The guidance for inclusion of principal design criteria (PDC) may be incomplete, since only "LMP outcomes" are addressed, and other topics from Part 50 App. A (like Monitoring Fuel &

Waste Storage) are not clearly included for consideration Hi This statement is not correct For plants that use the NEI 18-04 methodology, the PDC that flows from the LMP methodology and are needed to support the LMP-based safety case are based on the RSFs and the Required Functional Design Criteria (RFDC). RFDCs are used to supplement or modify ARDCs in developing PDCs. RG 1.232 should be referenced since there are other PDCs that are not tied to RFDCs (e.g., ARDCs 1 through 4).

Section 5.3 seems to imply that PDCs are only for DBEs and DBAs. What design criteria are applied to address BDBEs?

Section 5.3: For plants that use the NEI 18-04 methodology, the PDC that flows from the LMP methodology and are needed to support the LMP-based safety case are based on the RSFs and the Required Functional Design Criteria (RFDC)

Section 5.6: Thus, the PSAR content for Chapter 5 should include functional decomposition of FSFs to RSFs, a preliminary set of RFDC/PDC with performance-based criteria From NEI 18-04 4.1 Task 7: RFDCs are defined to capture design-specific criteria that may be used to supplement or modify the applicable General Design Criteria or Advanced Reactor Design Criteria in the formulation of Principal Design Criteria.

The TICAP methodologies are trying to adapt the PDC concept to the affirmative safety case approach and equate the PDC to those associated with RSFs. In that approach, considering non-reactor sources could have associated RSFs and PDCs if high-consequence events might be associated with such inventories.

Other issues associated with the LWR GDC or ARDC may be addressed by other parts of an application.

Workshop #2

7 Issue Topic Priority Comments Disposition 7

The guidance includes a requirement to include testing/qualification plans for first-of-a kind (FOAK) safety-related SSCs for CP applications. This requirement is reflected in 50.43(e),

and also applies to the other types of applications covered in the guidance (COL, DC, OL) but is not discussed in the guidance for those other application types.

Hi 50.34(e)(1)(i): The performance of each safety feature of the design has been demonstrated through either analysis, appropriate test programs, experience, or a combination thereof 50.43(e) requires applicants to provide the collection of analyses, tests, OE, etc.

necessary to assure the expected performance of safety features. Does this safety feature requirement apply to both SR and NSRST SSCs?

Chapters 6 & 7 of the SAR in an application would reflect the required capabilities of SR and NSRST SSCs. Where would the proof of those capabilities be provided to address 50.43(e)? (Its noted that this topic is called out for FOAK SR SSCs reflected in two-step CP applications, but the document seems to be silent on the issue for DC, COL, ML).

Workshop #1 NRC believes that 50.43(e) testing is inherently fundamental to the safety case and should therefore be included under TICAP guidance.

TICAP believes that the NEI 18-04 methodology does not encompass the 50.43(e) regulation, but that results of 50.43(e) testing would likely appear in the technical justifications supporting the safety case (e.g., benchmark data for computer codes used to analyze DBAs).

This is an example of disagreement on the scope of the TICAP guidance. Additional clarity with respect to scope and NRC expectations will be needed.

Nevertheless, TICAP will take another look at whether and, if so, how the 50.43(e) testing could be addressed by TICAP.

TICAP will modify its guidance to reflect that it is not just CPs but DCs and COLs that may invoke FOAK testing as special treatments.

8 Issue Topic Priority Comments Disposition 8

The level of detail in the SAR, supporting information placed on the docket, and information that is available for audit were identified as potential items for further discussion during the TICAP tabletop exercises.

During the TICAP tabletop exercises it was also noted that there is a distinction between items incorporated by reference (IBR) into the SAR and references to the SAR. IBRd item is considered to be part of the licensing basis for the plant.

Hi Discuss that if the staff relies on something they review as part of an audit to make their safety finding, that the specifics of that item then need to be elevated into the FSAR or an IBR document?

Make clear that reports that are IBRd are part of the licensing basis and change control process.

Section 1.2 states that the site attributes relevant to the safety case are in Chapter 2. There is no site information in Chapter 2.

There is no mention of fuel qualification.

RG 1.233 provided clarifications in certain areas. Does the TICAP guidance document intend to include these?

Workshop #1 TICAP understands that NRC citing an item in an audit report does not put that in the licensing basis.

TICAP confirmed that IBR in the SAR makes the information in the IBR reference part of the licensing basis and subject to the NRC change control processes.

TICAP explained that the reference to site information in Chapter 2 is based on the understanding that ARCAP will address site information there.

The treatment of fuel qualification will be discussed in ARCAP/TICAP discussions in Workshop #3.

TICAP stated that the applicant is responsible for ensuring it is addressing Reg Guide 1.233 including clarifications and limitations therein. TICAP does not see much daylight between NEI 18-04 and Reg Guide 1.233.

9 Issue Topic Priority Comments Disposition 9

During the discussion of non-safety related with special treatment (NSRST) structures, systems, and components (SSC) SAR content, the NRC staff raised a question regarding where the reliability information for these SSCs would be located (e.g., PRA or SAR) and what this information might entail. The NRC staff believes further discussion on this topic would be beneficial.

Hi SAR should describe reliability targets and performance requirements used as input to the PRA for SSCs that were used to develop the selection of special treatment requirements (i.e., programmatic actions used to maintain performance within the design reliability targets).

Section 6.2 states that the SSC reliability and availability information will not be in the FSAR. This is design basis information that is needed for determining the effectiveness of the maintenance program, the reliability assurance program and the ISI/IST programs. What is the basis for excluding it from the FSAR?

Section 7.1 defines NSRST special treatment requirements, no tie to performance targets Section 8 plant programs has special treatments for SR SSCs and NSRST SSCs may involve programs relied upon to provide reasonable assurance The introduction to Chapter 6 says This further detail [Chapter 6] includes SRDC, reliability and capability performance-based targets, and special treatment requirements to provide sufficient confidence that the performance-based targets intended in the design will be achieved in the construction of the plant and maintained throughout the licensed plant life. This statement appears to support that these targets should be in SAR.

It may be acceptable to point to where the information resides (e.g., reliability assurance program) versus putting actual reliability assumptions in the SAR.

Workshop #1 NRC believes the reliability targets should be provided in the SAR. NRC notes that NEI 18-04 stated the reliability and capability targets for SR and NSRST SSCs, and special treatment requirements for SR and NSRST SSCs define safety-significant aspects of the descriptions of SSCs that should be included in safety analysis reports. NRC further believes the information should be in the SAR.

TICAP believes the targets should be owner-controlled information, not maintained in the SAR. TICAP acknowledges the NEI 18-04 statement but believes TICAP guidance specifically for the SAR can supersede NEI 18-04 statements on SAR content. TICAP acknowledges that one in the draft guidance (introduction to Chapter 6) is not aligned with the TICAP position, but that statement was mistakenly included in the April 15, 2021 draft guidance.

TICAP and NRC will consider the issue further and revisit it at Workshop 3.

10 Issue Topic Priority Comments Disposition 10 The SAR content should focus on presenting the results of implementing the LMP process. For discussion purposes, it may be beneficial to discuss what type of documentation may exist from implementing the LMP process by the applicant, including narrative on the iterations in the process, and the deliberations and decisions of the integrated decisionmaking process (IDP) and whether this documentation may be something that is audited by the NRC staff.

Hi The description should address each of the decision guidelines described in Section 5.9.3 of NEI 18-04, including the basis for concluding the guideline has been met. For those guidelines where a quantitative measure can be provided, those measures used in the decision-making should be provided.

Numerous places in 18-04 detail documentation needs for bases or decisions.

The TICAP report should highlight what is documented in a TR, and what is in the SAR Related to item 8 Workshop #1 See disposition of Issue 3b.

11 NEI 18-04 (Section 3.2.2 - Task 6) states that, where possible, external events are to be analyzed in the PRA but, in some cases, may be selected and treated deterministically. There is no discussion in the TICAP guidance document about how to select and treat external events selected using a deterministic approach. Accordingly, the VTR report did not address this topic.

Hi There is Note on Page 51 that reads Note: The development of the DBEHLs is addressed by ARCAP and summarized in SAR Chapter 2.

Section 6.1.1 states that the design only needs to protect against external hazards with a frequency greater than 1 E-4/yr. Does this exclude BDBE external hazards from consideration?

Section 2.2 includes external events in the PRA. How are deterministically selected external events addressed in the PRA?

Additionally, incorporation of external hazards into the LBE determination process lacks basis and detail in 18-04 and the TICAP document.

Proposed 10 CFR 53.510(a) sets the design basis external hazard levels (DBHELs) at 1E-5/plant-year. RG 1.208 (seismic) establishes the site-specific ground motion response spectrum (GMRS) such that the frequency of significant inelastic deformation (FOSID) is 1E-5/y. RG 1.76 (tornados) and RG 1.221 (hurricanes) set DBHELs at 1E-7/y.

Workshop #3

11 Issue Topic Priority Comments Disposition 12 The discussion of DID in Section 4.2 of a SAR developed using the TICAP guidance is a good candidate for discussion as part of the upcoming workshops with the NRC/INL staff.

Hi Section 4.2 it states Note that the above information [topics listed in NEI 18-04 Table 5-1] is provided for background, and there is no requirement to address each topic in the SAR material. How does an applicant address this?

Related to one of the sub-bullets in item 3 - Workshop #1 See disposition of Issue 3b.

13 Based on internal discussion with the staff - believe a discussion of principal design criteria guidance embedded in draft industry document is appropriate in accordance with eVinci TICAP tabletop exercise comments HI Note that the guidance more accurately reflects the NEI 18-04 PDC development than was performed by eVinci.

Workshop #2 14 Currently the scope of the TICAP guidance document covers only COLs.

The scope of the TICAP guidance document should be expanded to include applicability for OL applicants under Part 50 and the supplemental guidance for the two-step licensing process should be limited to just CP applicants.

Hi The guidance document needs to also address scopeof ESP, DC and ML applications. Regarding ESPs, the staff believes an applicant using the TICAP guidance might leverage information from an ESP in developing their application (e.g., informing the DBEHL determination).

The level of detail and design maturity for an OL application is expected to be the same as for a COL applicant. By incorporating this comment the guidance for CP applicants can be made more clear and specific - currently the entries under the Two Part Licensing Process are confusing, inaccurate in some places, and lack specificity in others.

On 4/2/2021, NEI submitted comments (ML21092A115) on the draft CP ISG.

One comment stated that the NRC should not be requiring that the design and analysis for a CPA be at the same level of completion as for a COLA. This differs from the TICAP statement.

Workshop #1 TICAP to consider changes to clarify that alternative licensing paths two-step licensing guidance is applicable to the CP, not to the OL, and that the baseline TICAP guidance is applicable to the OL.

NRC to provide details of examples of TICAP guidance departing from NEI positions as stated in NEI comments on the draft construction permit Interim Staff Guidance.

15 For supplemental guidance for Design Certifications there are no entries for several sections. Need to clarify intent for these no entries (I.e., guidance provided for COLs applies) or if additional discussion is intended Med Similar to #14, all licenses should be covered Workshop #1 TICAP clarified that no entry for DC means no adjustments to the baseline guidance for DCs.

12 Issue Topic Priority Comments Disposition 16 For supplemental guidance for Design Certifications, it appears that perhaps only limited DID adequacy assessments might be able to be performed due to the fact that the expectations on operational program descriptions for DC applicants is not equivalent to COL applicants. May also have some impact on identification of special treatments.

DCs should address DID as part of the design including identification of needed special treatments. The only difference from a COL is the development of the operational program description which would not be expected in a DC.

Workshop #1 TICAP will revise guidance as needed to reflect DC adjustments due to the fact that DC does not address operating plant-specific topics.

17 The TICAP guidance document refers to licensing basis, however, there is a definition of current licensing basis contained in 10 CFR 54.3 which was necessitated by license renewal.

Should a reference to that definition be included in the guidance or should that definition be revisited and redefined for the purposes of use of the LMP approach or for inclusion in Part 53 for that matter. Question for discussion is whether or not the definition needs to be modified for the purposes of this guidance document or other advanced reactor guidance documents?

Med The staff notes that this issue could be considered as Part 53 language is developed for Subpart H and I.

Workshop #3?

18 There should be alignment on the proposal to not include licensing basis information in Chapter 1. The purpose, I think, is to also exclude Chapter 1 for the change process and reduce future regulatory burden. However, our current concept of the change process is 10 CFR 50.59 and it is not clear as to what the change process under Part 53 might be.

Need to align on the proposal that Chapter 1 is not licensing basis information w/o having a clear definition of licensing basis for LMP-based SARs or even what the change process would entail.

Workshop #3?

13 Issue Topic Priority Comments Disposition 19 Several sections refer to tables in the LMP Tabletop Exercise Report or to useful guidance in the MHTGR PSID document. (ERO)

Hi It would be more useful to include the tables and useful guidance referred to within the TICAP guidance document.

Workshop #1 See Disposition of Issue #4 20 Around Workshop #3, the staff is considering discussion of a draft TICAP RG and an ARCAP roadmap ISG to start the discussion on how industrys guidance is envisioned to fit within TICAP and the staffs initial thinking on where industrys TICAP guidance is envisioned to be supplemented (e.g.,

fuel qualification, ASME Section III Division 5, design review guide for I&C)

Med Workshop #3?

21 The term safety case is not currently used in NRC licensing processes.

Hi TICAP page 4 states The term safety case is a collection of statements that, if confirmed to be true by supporting technical information, establishes reasonable assurance of adequate protection for operation of the nuclear power plant described in the application. TICAP Figure 1 on page 6 shows the relation between TICAP and an advanced reactor license application; specifically, the affirmative safety case addressed by TICAP is necessary, but not sufficient, to establish reasonable assurance of adequate protection. Need alignment on what a safety is and, equally important, what it is not.

Workshop #2

14 Issue Topic Priority Comments Disposition 22 The staff has provided industry with a list of NRC observations from the TICAP tabletop exercises. To date, industrys feedback on these observations has been limited to the first two TICAP tabletop exercise observations. The NRC staff would be interested in industrys feedback on the NRC observations for the last two TICAP tabletop exercises (i.e., the eVinci microreactor, and the molten chloride reactor experiment (MCRE)). In particular, the NRC staff would be interested in whether industry identifies potential workshop items from eVinci and MCRE TICAP tabletop exercises that are not captured in the items identified above.

Hi Workshop depends on insights from industry 23 The NRC staff finds that additional information and clarity on PRA is needed in the TICAP guidance.

Hi In Section 2.1.1, the overview of PRA needs additional clarity regarding peer review, the use of technically adequate PRA, the level of details, and so on. In addition, PRA for construction permit applications needs discussion with the NRC staff since there is ongoing discussions on the subject as part of the NRC staffs ongoing development of guidance on construction permit.

In Section 2.1.2, the summary of key PRA results should include other information such as key assumptions, the results and insights from importance, sensitivity, and uncertainty analyses, and so on.

Although other Chapters (i.e., Chapter 3 and 4) include some of the PRA results or insights (such as risk-significant SSCs, human actions, etc.), it may be useful to have these key results under Section 2.1.2 to have the comprehensive PRA results in one place. Alternatively, a set of pointers (not at the Chapter level) at the individual topic areas may be included in Section 2.1.2.