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Industry Slide Presentation for 8-22-23 Meeting on ARCAP-TICAP and DG-1404 Guidance Documents
	ML23230A014
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Site:	Nuclear Energy Institute
Issue date:	08/22/2023
From:	Holtzman B; Nuclear Energy Institute
To:	; Office of Nuclear Reactor Regulation
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Advanced Reactor Stakeholder Meeting:

Comments on Draft NRC Reg Guide DG-1404 and Draft ISGs August 22, 2023

Introduction

Following extensive interactions with the NRC throughout 2021, the Nuclear Energy Institute (NEI) submitted NEI 21-07 Technology Inclusive Guidance for Non-Light Water Reactors - Safety Analysis Report Content for Applicants Using the NEI 18-04 Methodology to the Nuclear Regulatory Commission (NRC) for endorsement on March 1, 2022

NEI 21-07 is intended to be part of a streamlined and predictable risk-informed, performance-based (RIPB) licensing pathway to deployment for advanced reactors under 10 CFR Part 50 or 52

The NRC made draft Regulatory Guide DG-1404 on NEI 21-07 available on ADAMS on May 18, 2023, in conjunction with a number of interim staff guidance documents (ISGs) related to advanced reactors

NEI provided detailed comments on DG-1404 and the ISGs on August 10, 2023

The purpose of this presentation is to ensure a common understanding of the NEI comments on DG-1404 and the issues underlying them ©2023 Nuclear Energy Institute 2

Meeting Approach

Discuss the industry perspective on the guidance and how the comments are intended to achieve the goals for that guidance

Discuss specific comments and concerns related to DG-1404

Where slides address specific comments from the August 10, 2023, NEI comment letter, the comment number(s) are noted in red type

Discuss some specific comments and concerns related to the interim staff guidance documents

Overview of Guidance

Regulatory guidance should be specific, straightforward, understandable, and implementable

Information included in the safety analysis report (SAR) should be limited to that needed to demonstrate reasonable assurance of adequate protection and satisfy applicable regulations

DG-1404 and NEI 21-07, in combination, should address the information necessary to describe the key results of the application of the NEI 18-04 RIPB methodology and enable the NRC to perform its regulatory review function efficiently and effectively

The advanced reactor demonstration projects and other forthcoming applications plan to use the NEI 18-04 RIPB methodology, underlining the importance of providing consistent and usable guidance in DG-1404

Overview of Guidance (cont.)

Guidance should be clear and straightforward

Language should be straightforward and easy to understand

To the extent practical, guidance should be in one location, not spread among different sections and documents

Regulatory guide additions should provide distinct material that is both required and not already present in NEI 21-07

Repeating or restating material already provided in NEI 21-07 is counterproductive and detracts from the guidance

Redundancy forces users to analyze both documents in detail in an attempt to discern what is new and what is simply repeated

Regulatory guide clarifications should be specific and understandable with respect to refined expectations for applicants

DG-1404 Discussion Themes

1. Details on the probabilistic risk assessment (PRA) in the SAR

2. Change control considerations

3. SAR content beyond NEI 21-07 guidance

4. Light water reactor (LWR) guidance

5. Scope of guidance

6. SAR organization

7. Redundant or unclear guidance

Issue 1 - PRA Clarification C.3.e

Clarification C.3.e relates to information on the PRA at the CP stage of an application and addresses the sentence If conformance to ASME/ANS RA-S-1.4-2021 is planned, a simple statement to that effect should be sufficient.

The NRC clarification reminds the applicant that more information is needed at the CP stage than this simple statement

However, that point is already amply clear from a plain English reading of NEI 21-07 Section C.2.1.1 (CP Content), which states In either case, the applicant should address the last five items in the Section 2.1.1 list, consistent with the state of the plant design and the PRA at the time of CP application.

The addition is not needed and is counterproductive [Comment 22]

Issue 1 - PRA Addition and Clarification C.4.a

The introductory part of Addition and Clarification C.4.a addresses documentation of PRA source term and radiological consequence information - an issue that was resolved pursuant to discussions in 2021 and 2022 that led to changes in the guidance for NEI 18-04 Sections C.2.1.1, C.3.3.1, C.3.4.1, and C.3.5.1

The basis for the introductory language is not clear given that NEI 21-07 already addresses the issue

The addition/clarification is not needed and is counterproductive

[Comment 26]

Issue 1 - PRA Addition and Clarification C.4.a(1)

The NRC comment addresses inclusion of supporting data that is significant to determining whether the frequency-consequence targets and quantitative health objectives (QHOs) are met and the development of the analysis conclusions on risk significance, SSC classification, or DID adequacy.

To the extent the comment is on QHOs, those are addressed in SAR Chapter 4, not SAR Chapter 3

The comment is vague and unclear

What does data that is significant to conclusions on risk significance, SSC classification, or DID adequacy mean?

This criterion is open-ended and subjective

The addition and clarification is not needed and is counterproductive

Issue 1 - PRA Clarification C.4.b

The NRC asserts a conflict between NEI 21-07 Section C.2.1.1 and guidance on SAR Sections 3.3.1, 3.4.1, and 3.5.1 on level of detail in the PRA for AOOs, DBEs, and BDBEs

Industry does not agree there is a conflict

Section C.2.1.1 specifies particular information to be include in the SAR, recognizing that the bulk of the PRA information is to be maintained as plant records

Guidance for Section C.2.1.1 was worked out to in 2021 and 2022 to address NRC concerns about certain types of information

Guidance for SAR Sections 3.3.1, 3.4.1, and 3.5.1 already provide for event-specific information PRA model information in Chapter 3

The clarification is not needed and is counterproductive [Comment 29]

Issue 1 - PRA Clarification C.5.b

Addition C.5.b requests detailed information underpinning the PRA calculations addressing QHOs in Section 4.1

This change would greatly expand the PRA level of detail required in the SAR with no commensurate benefit

The information in question would be addressed in the PRA peer review, and it would be available for NRC to inspect in an audit

It is not clear the NRC appreciates the scope of this overly broad requirement

- e.g., (5) key modeling assumptions, (8) uncertainty/ sensitivity analysis performed

Because these are integrated analyses, the requirement would apply to each and every PRA event sequence family that involves an offsite dose

Literal compliance may result in information on the order of SAR Chapter 19 for advanced light water reactors

The clarification is not needed and is counterproductive [Comment 34]

Issue 2 - Defense in Depth Change Control

Addition C.5.d would require that the applicant provide a change control process for DID in the SAR.

The requirement is inappropriate for a SAR

Industry is working with the NRC on a change control process for licensees that follow NEI 18-04

This is the Technology Inclusive Risk Informed Change Evaluation (TIRICE) Project

Draft NEI Guidance Document NEI 22-05 includes and should address the issue

The addition is not needed and is counterproductive [Comment 36]

Issue 2 - Non-PRA Analyses

Addition C.3.h would expand the coverage of SAR Chapter 2 by requiring applicants identify and describe the non-PRA analysis and calculation methodologies used to establish their licensing bases, and it is apparently motivated by change control considerations

This addition was never discussed in the extensive interactions preceding the submittal of NEI 21-07 Rev. 1

analysis and calculational methodologies used to establish their licensing basis is ill-defined, overly broad, and subject to misuse

It is a circular definition

The SAR is not the compendium of all analyses and calculations related to a nuclear power plant

Issue 2 - Non-PRA Analyses (cont.)

The tie to change control as justification for Addition C.3.h is inappropriate because industry is working with the NRC in the TIRICE project to address change control in the context of a plant following the NEI 18-04 methodology

Literal compliance with the guidance would be at cross-purposes to the intended organization of NEI 21-07

LBE analyses would not be described in Chapter 3

SSC analyses would not be described in Chapters 6 and 7

The purpose of Chapter 2, capturing cross-cutting analyses and methodologies, would be defeated

Addition C.3.h is not needed and is counterproductive [Comment 25]

Issue 3 - Reliability and Capability Targets

The last two sentences of the first paragraph of DG-1404 Section 7 are confusing and do not convey appropriate guidance to the applicant

The penultimate sentence requests a discussion of how the applicant intends to confirm, at the OL stage, that the reliability and capability performance targets assumed in the PRA have been met

NEI 21-07, Section C.6.2 already addresses reliability and capability targets, including plant programs used to maintain them

Section C.6.2 makes it clear that reliability and capability targets are not "assumed in the PRA" as stated by DG-1404, but instead informed by PRA information and include the consideration of the NEI 18-04 criteria for plant capability DID adequacy

The embedded new requirement for CP applicants (how to confirm targets at the OL stage) is unnecessary and burdensome

Issue 3 - Reliability and Capability Targets (cont.)

The last sentence of the first paragraph in DG-1404 Section 7 is confusing because it convolves inappropriately special treatments with testing and validation

Testing and validation are types of special treatments [Comment 41]

Issue 3 - Instrumentation and Control (I&C)

Additions C.7.b(1) and C.8.a(1) specify additional information for I&C SSCs classified as safety-related and non-safety-related with special treatment, respectively

Singling out specific SSCs deterministically for additional documentation requirements (as these additions would do) is antithetical to a risk-informed, performance-based approach

Special treatments are already addressed adequately in the NEI 21-07 guidance, and no justification is provided for placing additional burdensome requirements for some SSCs

This requirement is entirely new and was never discussed as part of the extensive give-and-take that took place prior to the submittal of NEI 21-07

The additions are not needed and are counterproductive [Comments 48 and 52] ©2023 Nuclear Energy Institute 17

Issue 3 - Human Factors

Addition C.5.c directs the inclusion of additional information on human factors in SAR Chapter 4 if not included in SAR Chapter 6 or 7

Per discussions between industry and NRC, human factors are to be addressed in SAR Chapters 6 and 7 (in conjunction with the associated SSCs) and in SAR Chapter 11 per draft ARCAP ISG, DANU-ISG-2022-05, Organization and Human-System Considerations

There is no compelling nexus between SAR Chapter 4 and human factors as discussed in several NEI 21-07 meetings

The words in DG-1404 do not provide clear and actionable guidance

The guidance is an open-ended kitchen sink approach of tell me everything about human factors

The addition is not needed and is counterproductive [Comment 35]

Issue 3 - Fuel Qualification

Addition C.6.b directs applicants to address fuel qualification in SAR Chapter 5

This addition is backward-looking and inappropriate for a SAR

Once the SAR is submitted, fuel qualification should be complete

It is fundamentally an issue for preapplication engagement

There is no need to single out fuel in a deterministic manner for safety-related status

The systematic, risk-informed NEI 18-04 process should properly categorize SSCs

The requested fuel qualification plan information is not needed but if it were, providing it in SAR Chapter 5 would be wholly inappropriate

The addition is not needed and is counterproductive [Comment 40]

Issue 3 - Codes and Standards

Additions C.7.b(2) calls for justification in the SAR for the use of chosen codes and standards

The requirement goes beyond standard practice for LWRs, including advanced LWR designs

This requirement was not raised during discussions of NEI 21-07 prior to the submittal of the document for NRC endorsement in 2022

The addition is not needed and is counterproductive [Comment 49]

Issue 4 - Light Water Reactor (LWR) Guidance

Industry has concerns with the letter and the spirit of Addition C.2.e, which would levy substantial documentation requirements even though they are largely nonapplicable to non-LWRs

Item 1: Generic safety issues (GSIs), unresolved safety issues (USIs), and TMI action items are largely LWR-centric

They should not be presumed to be applicable to non-LWRs

Applying LWR GSIs, USIs, and TMI action items to non-LWR advanced reactors is inconsistent with the concept of risk-informed, performance based regulation

Issue 4 - LWR Guidance (cont.)

Item 1: GSIs, USIs, and TMI action items (cont.)

There is no regulatory requirement that non-LWR Part 50 applicants address GSIs, USIs, and TMI action items in the SAR

NRC should not impose unnecessary requirements related to GSIs, USIs, and TMI action items on Part 50 applicants

If NRC retains Addition C.2.e Item 1, NRC should clarify that it does not presume applicability to non-LWRs

Issue 4 - LWR Guidance (cont.)

Item 2: Regulatory guides

Regulatory guides are not regulatory requirements and most were developed specifically for LWRs

There should be no presumption that regulatory guides are applicable to non-LWRs and NRC should be clear on that point

If the NRC retains Addition C.2.e Item 2 for SAR Chapter 1, it should be clear that the expectation is a simple list of material addressed elsewhere in the SAR, not a justification for the disposition of each and every regulatory guide

Issue 4 - LWR Guidance (cont.)

Item 3: Codes and Standards

Codes and standards will be addressed in appropriate sections of the SAR

If the NRC retains Addition C.2.e Item 3 for SAR Chapter 1, it should be clear that the expectation is a simple list, with any substantive information provided in later chapters as presently directed by NEI 21-07

See Comment 16 covering Items 1, 2, and 3

Issue 5 - Scope: Manufacturing Licenses (MLs) and Standard Design Approvals (SDA)

NEI 21-07 Section A.3 states the document applies to specific licensing approaches

Part 52 combined construction permit and operating license (COL)

Part 52 design certification (DC)

Part 50 two-step license (CP/OL)

Guidance for an ML or SDA should be very similar to guidance for a DC

Design-centered guidance

Both an ML and an SDA contemplate a CP application under Part 50 or a COL application under Part 52

Issue 5 - Scope: MLs and SDAs (cont.)

DG-1404 states in several places the document applies to the aforementioned approaches plus a Part 52 manufacturing license (ML) and a Part 52 standard design approval (SDA)

However, DG-1404 provides no specific guidance for applicants pursuing an ML or an SDA

Industry agrees that an ML or SDA applicant following NEI 18-04 should be able to use the NEI 21-07 guidance with appropriate adjustments

Rather than providing no recognition of the lack of ML- and SDA-specific guidance, NEI recommends that DG-1404 direct such applicants make appropriate adjustments to the existing guidance

It is expected such adjustments would be the subject of preapplication engagement with the NRC [Comment 2]

Issue 5 - Scope: Non-LMP Approaches

Addition C.2.c provides guidance to " nonLWR applicants pursuing a CP under 10 CFR Part 50 using a riskinformed, performancebased approach other than the LMP ."

NEI 21-07 is for applicants using LMP, so this is clearly beyond scope

NEI 21-07 provides flexibility for applicants, but it is not reasonable to expect it to be used by applicants employing a totally different approach than LMP

NEI 2107 Section C.1.3.1 places the onus on the applicant which deviates from NEI 1804 to address and justify those deviations

It is inappropriate for a reg guide that endorses NEI 21-07 to attempt to address all possible deviations from NEI 21-07

The addition is not needed and is counterproductive [Comment 14]

Issue 6 - Deterministic Material in SAR Chapter 3

NRC wants applicants to include certain information related to deterministic events and requirements in SAR Chapter 3

Industry would like to ensure the events are clearly delineated as separate from licensing basis events (AOO, DBEs, BDBEs, and DBAs) as defined in NEI 18-04

Industry recommends the NRC Regulatory Guide instruct applicants to put the information in a new Section 3.7, Special Event Analyses [Comment 30]

Issue 6 - Deterministic Material (cont.)

Addition C.4.c(1) addresses aircraft impact assessments per 10 CFR 50.150

The guidance is different from the guidance provided in the ARCAP Roadmap ISG DANUISG202201 (p. 39 of 56)

Rather than have different and potentially conflicting guidance in multiple documents, NRC should put the guidance in one location and referred to by reference in other locations, if needed [Comment 31]

Issue 6 - Deterministic Material (cont.)

Addition C.4.c(2) addresses mitigation of specific beyond design basis events per 10 CFR 50.155

A comprehensive evaluation of such events should not be necessary at the CP stage

Industry requests the NRC add guidance to the effect that information addressing this regulation is not required at the CP stage unless the applicant is requesting design finality [Comment 32]

Issue 7 - Defense in Depth (DID) Guidance

Addition C.5.a discusses aspects of DID and then solicits a discussion on DID adequacy assessment processes for the life of the plant

The first two sentences are essentially quotes from NEI 21-07 and are therefore unnecessary

The sentence The CP application should provide a discussion in the SAR to establish DID adequacy is worded awkwardly, and it seems to be soliciting a description of the approach to DID

NEI 18-04 already describes the approach to DID

NEI 21-07 already addresses requirements for DID information in the SAR

Issue 7 - Defense in Depth Guidance (cont.)

Concerning the DID adequacy discussion, NRC goes on to say in Addition C.5.a A discussion in the SAR to implement the DID adequacy assessment processes in RG 1.233 is considered acceptable for this purpose.

The sentence is worded awkwardly and the intent is unclear

DG-1404 then addresses the situation in which the applicant does not intend to follow Reg Guide 1.233

Applicants are already required to explain deviations from NEI 21-07 and Reg Guide 1.233 (see NEI 21-07 Section C.1.3.1)

Addition C.5.a is not needed and is counterproductive [Comment 33]

Issue 7 - Incorporated by Reference

Clarification C.3.a addresses separate licensing documents that are incorporated by reference in the SAR, and states that NEI 2107, Rev.

1, does not address them

NEI 21-07 does address the issue thoroughly in Section B.3, including a reference to NEI 98-03, Rev. 1

Even if the clarification were necessary, which it is not, it would be inappropriate to make is specific to Section C.2 of NEI 2107 (guidance on SAR Chapter 2, Methodologies and Analyses)

The guidance would apply to the entirety of the SAR

That is why the guidance on incorporated by reference is provided in NEI 21-07 Section B.3, which is general guidance

The addition is not needed and is counterproductive [Comment 18]

Issue 7 - PRA Clarification C.3.f

Clarification C.3.f addresses a clarifying note in NEI 21-07 Section C.2.1.1 pertaining to PRAs that do not follow the non-LWR PRA standard

The NEI 21-07 note in question clearly applies to the baseline guidance in NEI 21-07 which is for a COL application

Guidance for a CP applicant is in the following section, entitled Two-Step Licensing (CP Content)

That CP guidance addresses both situations - following the non-LWR PRA standard and not following the standard

The NRC clarification introduces confusion that did not previously exist

The addition is not needed and is counterproductive [Comment 23]

Issue 7 - PRA Addition and Clarification C.4.a(2-4)

The NRC comment seeks to ensure that all of the information in the second bulleted list for certain AOOs, DBEs, and BDBEs is provided

In each case, NEI 21-07 states the following information should be provided or similar words (see guidance in NEI 21-07 for SAR Sections 3.3.1, 3.4.1, and 3.5.1)

Example in Section 3.3.1 The following information should be provided for any AOO with a release.

The following information is clearly the second bulleted list

The current NEI 21-07 language is clear and the NRC comment appears to be guarding against an impossible misinterpretation

The additions/clarifications are not needed and are counterproductive

[Comment 28]

Issue 7 - DBHL Guidance

Clarification and Addition C.7.a addresses DBHL loads and related analyses and evaluations

The necessary guidance is already provided in NEI 21-07 Section C.6.1.1

The C.7.a statement Preapplication interaction with the staff may be appropriate to determine the necessary level of information does not add value

The same statement could be included in every section of DG-1404

The ARCAP Roadmap ISG already provides a robust discussion on the use of preapplication guidance

The DG-1404 guidance neither clarifies nor adds to the NEI 21-07 guidance

The clarification and addition is not needed and is counterproductive

Issue 7 - Principal Design Criteria (PDC)

Addition C.6.a(1), Clarification C.6.a(2), and Addition C.6.a(3) address various aspects of the approach to PDC as presented in NEI 21-07 Section C.5.3

The DG-1404 PDC discussion repeats material contained in NEI 21-07 about PDC, but it is not apparent what is actually added or clarified in DG-1404

The applicant will be left to puzzle through a page of guidance in DG-1404 and guess what, if anything, the NRC desires that is different from what is already in NEI 21-07

NRC should delete the additions and clarifications in C.6.a or revise the material to make it clear what the ask is [Comments 37-39]

Issue 7 - Addition C.2.b on Scope of the SAR

Addition C.2.b reminds the applicant there is more to a SAR than the documentation of the NEI 18-04 process as provided in NEI 21-07.

This point is already amply made in NEI 21-07 (Sections A.1 and A.3) and in the ARCAP Roadmap ISG

e.g., A.3: This guidance addresses only the portion of an advanced reactor SAR related directly to the implementation of the NEI 18-04 methodology. Concurrently with the development of this document, NRC is developing guidance for the remaining parts of an advanced reactor license application (including part of the SAR) in its Advanced Reactor Content of Application Project (ARCAP).

It is simply inconceivable an applicant would get this wrong

The addition is not needed and is counterproductive [Comment 13]

Issue 7 - Other Unnecessary Material in Body of DG-1404

There are statements in parts of DG-1404 outside of specific additions and clarifications which industry considers unnecessary and, in some cases, inaccurate or misleading.

Industry provided specific comments to the NRC identifying those instances

As with the additions and clarifications, industry believes it is important to avoid restating guidance that is already in NEI 21-07

These slides do not address those comments individually, but industry is ready to discuss any of the comments if NRC has any questions or concerns with them

Other Package Comments to Highlight

ARCAP goal was guidance applicable for any technology (non-LWR and LWR), any licensing approach (LMP, classical, etc.), and any licensing path (CP, COL, DC etc.)

Maintain independence of Part 50/52 and Part 53 efforts

Disagree with including guidance based on unapproved on-going rulemaking efforts

Facility Safety Program itself has concern as noted in Part 53 comments and summarized here

Thank You for Your Time and Attention

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