ML23284A389
| ML23284A389 | |
| Person / Time | |
|---|---|
| Site: | Nuclear Energy Institute |
| Issue date: | 10/10/2023 |
| From: | Holtzman B Nuclear Energy Institute |
| To: | Office of Administration |
| References | |
| 88FR61989 00008, NRC-2022-0073, DG-1404 | |
| Download: ML23284A389 (1) | |
Text
10/11/23, 7:55 AM blob:https://www.fdms.gov/79fbfbb6-a0d5-4714-aadf-c48a46b4cd44 SUNSI Review Complete Template=ADM-013 As of: 10/11/23, 7:54 AM E-RIDS=ADM-03 Received: October 10, 2023 PUBLIC SUBMISSION ADD: Jen Scro, Marica Status: Pending_Post Carpentier, Max Smith, Tracking No. lnk-sirj-eqdm Mary Neely Comments Due: October 10, 2023 Comment (8)
Publication Date:
Submission Type: Web 9/8/2023 Citation: 88 FR 61989 Docket: NRC-2022-0073 Guidance for a Technology-Inclusive Content of Application Methodology to Inform the Licensing Basis and Content of Applications for Licenses, Certifications, and Approvals for Advanced Reactors Comment On: NRC-2022-0073-0005 Draft Regulatory Guide: Guidance for a Technology-Inclusive Content-of-Application Methodology To Inform the Licensing Basis and Content of Applications for Licenses, Certifications, and Approvals for Non-Light-Water Reactors Document: NRC-2022-0073-DRAFT-0013 Comment on FR Doc # 2023-19451 Submitter Information Email: txc@nei.org Organization: Nuclear Energy Institute General Comment NEI Comments on Draft Regulatory Guide (DG) DG-1404, Revision 1, Docket ID NRC-2022-0073 Attachments 10-10-23_NRC_NEI Comments on Draft Regulatory Guide (DG) DG-1404_Revision 1 NEI Consolidated Comments on DG-1404 Rev 1 blob:https://www.fdms.gov/79fbfbb6-a0d5-4714-aadf-c48a46b4cd44 1/1
Benjamin Holtzman 202.230.1740 Director, New Nuclear Technical & Regulatory Services bah@nei.org nei.org 1201 F Street NW, Suite 1100 Washington, DC 20004 October 10, 2023 Mr. Mohamed Shams Director, Division of Advanced Reactors and Non-Power Production and Utilization Facilities (DANU)
Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Washington, DC 20555-0001
Subject:
Comments on Draft Regulatory Guide (DG) DG-1404, Revision 1, Docket ID NRC-2022-0073 Project Number: 689 Submitted via Regulations.gov
Dear Mr. Shams:
On behalf of the nuclear energy industry, The Nuclear Energy Institute (NEI) 1 is pleased to submit comments to the Nuclear Regulatory Commission (NRC) on the draft regulatory guide DG-1404, Revision 1, Guidance for a Technology-Inclusive Content of Application Methodology to Inform the Licensing Basis and Content of Applications for Licenses, Certifications, and Approvals for Non-Light-Water Reactors.
NEI previously provided comments on DG-1404, Revision 0, by letter dated August 10, 2023.
The Federal Register notice [NRC-2022-073] - which provides DG-1404, Revision 1, for comment - denotes that the only difference between DG-1404, Revision 0, and DG-1404, Revision 1, is the addition of a new Appendix B and conforming changes in the body of DG-1404. In the attachment to this letter, NEI provides specific comments and suggested changes related to the Appendix B material. NEI also provides below a general comment on the Appendix B material and its relationship to DG-1404.
There is a fundamental issue regarding the new information in Appendix B causing confusion.
Most of the Appendix B information appears to provide guidance on NRCs expectations regarding how an applicant should perform an acceptable probabilistic risk assessment (PRA) in 1
The Nuclear Energy Institute (NEI) is the organization responsible for establishing unified industry policy on matters affecting the nuclear energy industry, including the regulatory aspects of generic operational and technical issues. NEI's members include entities licensed to operate commercial nuclear power plants in the United States, nuclear plant designers, major architect/engineering firms, fuel cycle facilities, nuclear materials licensees, and other organizations and entities involved in the nuclear energy industry.
Mr. Mohamed Shams October 10, 2023 support of a construction permit (CP) application for a non-light water reactor (non-LWR) following NEI 18-04. However, the intent of DG-1404, Revision 1, is to provide guidance on the content to be documented in the safety analysis report (SAR) as noted on page 1 of the draft regulatory guide. NEI discussed this concern with NRC staff during the September 26, 2023, public meeting on DG-1404, Appendix B. During that meeting the staff confirmed that the guidance provided in NEI 21-07, Revision 1, along with additional guidance in the body of DG-1404, is sufficient to address the expectations for SAR content related to the PRA at the construction permit application stage. Thus, the material in DG-1404 Appendix B has no relation to the stated purposes of NEI 21-07, Revision 1, or DG-1404.
NEI suggests two approaches to address the problem.
- 1. We believe the best solution is for NRC to reissue the material in Appendix B in a separate and more appropriate document, such as an Interim Staff Guidance (ISG) document, as the guidance in Appendix B exceeds the scope of NEI 21-07 and the purpose of DG-1404 (expectations for SAR and PSAR content).
- 2. Alternatively, NRC can make a global statement in the front of Appendix B acknowledging that the guidance provides staff expectations for the development of the CP PRA, not staff expectations for the documentation of the CP PRA in the PSAR. Such a statement should go on to state that the combination of the guidance on PSAR content in NEI 21-07, Revision 1, and the body of the regulatory guide are adequate.
Thank you for your time and attention to this important matter. Please contact me if you have any questions or require additional information.
Sincerely, Ben Holtzman
Attachment:
NEI Consolidated Comments on DG-1404 Rev 1 c: Robert Taylor, NRR, NRC John Segala, NRR, NRC Joseph Sebrosky, NRR, NRC William Reckley, NRR, NRC Anders Gilbertson, NRR, NRC Rebecca Ober, NRR, NRC Nuclear Energy Institute 2
NEI Consolidated Comments on NRC DG-1404 Rev 1 Attachment 1 October 10, 2023 DG1404 Appendix B Comment # Location Comment Proposed Change 1 General Most of the information provided in Appendix B provides guidance on NRCs NEI suggests two approaches to address the problem.
expectations regarding how an applicant should do an acceptable
- 1. NRC can reissue the material in Appendix B in a probabilistic risk assessment (PRA) in support of a construction permit (CP) separate and more appropriate document, such as an application for a non-light water reactor (non-LWR) following NEI 18-04. That Interim Staff Guidance (ISG) document. As the guidance introduces confusion because DG-1404 is a draft regulatory guide addressing in Appendix B exceeds the scope of NEI 21-07 and the NEI 21-07 which addresses the content for the safety analysis report (SAR),
purpose of DG-1404 (expectations for SAR and PSAR not how to perform analyses (including PRAs). In fact, the first page of DG-content), we believe that creating a separate guidance 1404 clearly states the guidance should be focused on SAR content, not how document is the best solution.
to do the analyses.
- 2. NRC can make a global statement in the front of The fundamental concern is that Appendix B does not clearly delineate Appendix B acknowledging that the guidance provides between 1) what is guidance for how to document the CP PRA and 2) what is staff expectations for the development of the CP PRA, guidance for how to do the CP PRA.
not staff expectations for the documentation of the CP One interpretation of this is that, NEI 21-07, Rev 1, plus the additions and PRA in the PSAR. Such a statement should go on to state clarifications in the body of DG-1404 is the totality of information to describe that the combination of the guidance on PSAR content in the preliminary SAR (PSAR) scope and level of detail (see B.7.1). Based on NEI 21-07, Rev 1, and the body of the regulatory guide discussions at the September 26, 2023, NRC public meeting on DG-1404 are adequate. If the NRC chooses this approach, please Appendix B, both industry and the NRC staff currently share this add the following paragraph after the three bullets on interpretation. However, it is also possible to interpret Appendix B as page 1 of Appendix B.
indicating that everything discussed in Appendix B must be described in the Unlike the body of the regulatory guide, this Appendix B PSAR as the guidance is located in an NRC document addressing expectations provides no guidance for the documentation of for SAR and PSAR content.
information in the safety analysis report (SAR) associated There are also specific instances in Appendix B that could be construed as with a reactor license application. NEI 21-07, Revision 1, adding on to the documentation requirements in NEI 21-07 (see for example as endorsed with additions and clarifications in the main B.3.6). body of this Regulatory Guide, already provides an acceptable approach and format for providing SAR Because Appendix B goes beyond simply guidance on PSAR content, it is documentation, including information associated with the imperative that there be a clear delineation between CP PRA guidance and CP PRA.
1
NEI Consolidated Comments on NRC DG-1404 Rev 1 Attachment 1 October 10, 2023 DG1404 Appendix B Comment # Location Comment Proposed Change 2 Multiple The text in sections noted below applies to how to perform a CP PRA, not how Action required as noted in Comment 1 to differentiate Locations to document the PRA in the PSAR. in the guidance between 1) information on how to B.2.3 B.5.2 perform the CP PRA and 2) what information regarding B.3.4 B.6.1 the CP PRA is needed for inclusion in the PSAR.
B.3.5 B.6.2 B.3.7 B.6.3 B.4.1 B.8.4 B.4.2 B.8.5 B.5.1 B.8.6 2
NEI Consolidated Comments on NRC DG-1404 Rev 1 Attachment 1 October 10, 2023 DG1404 Appendix B Comment # Location Comment Proposed Change 3 B.2.2 The text begins by stating Consistent with NEI 21-07, Revision 1, Section The guidance of B.2.2 is not needed and should be 2.1.1 but the PSAR guidance seems to go far beyond NEI 21-07. There are deleted.
technical requirements for each technical element in the PRA standard to Alternatively, revise B.2.2 to state, The CP applicant document assumptions made in addressing the supporting requirements, should clearly document internally in its records the key including those made to address the lack of design, site, and operational assumptions made in developing the PRA, including those information available to support the PRA. Hence this information is more that are relevant to the probability and consequence appropriately placed in the PRA documentation so it is presented in the models, and the selection of elements for models to context of the other supporting requirements selected to support the PRA incorporate.
which would be available to audit by the NRC. This level of detail of PRA information is too voluminous for inclusion in the CP application and is inconsistent with the concept in NEI 21-07 Section 2.1.1 for a two-step licensing submittal. The expectation that all key assumptions be documented in the SAR is substantially different from the guidance provided in NEI 21-07.
The Appendix B guidance is not well-bounded and is inappropriate for incorporation in the SAR, particularly at the CP stage.
NEI 21-07, Rev 1, Section 2.1.1 explicitly calls for documentation of site characteristics modeled or assumed in the radiological consequence evaluations. That is narrow and limited guidance related to assumptions.
Furthermore, NEI 21-07 Section 2.1.1 specifies that assumptions will be addressed in the appropriate SAR section. The NEI 21-07 text states Assumptions made in performing the PRA that are essential to the LMP-based affirmative safety case will be identified in the sections of the SAR to which they apply. For example, such assumptions that impact the selection and evaluation of LBEs will be noted in Chapter 3. PRA assumptions that are not essential to the safety case will not be included in the SAR but will be available in the plant records for NRC audit. The intent of this guidance was to avoid a compendium of assumptions in the front of the SAR which may or may not be pertinent to the safety case.
3
NEI Consolidated Comments on NRC DG-1404 Rev 1 Attachment 1 October 10, 2023 DG1404 Appendix B Comment # Location Comment Proposed Change 4 B.3.1 The information described in B.3.1.1 and B.3.1.2 are essentially covered in Action required as noted in Comment 1 to differentiate PSAR Chapters 3 and 4, respectively. It is not clear what the purpose of B.3.1 in the guidance between the information regarding the is, because it basically duplicates information already in NEI 21-07, Revision 1. CP PRA that is needed for inclusion in the PSAR, and other information.
As discussed in Comment 1, it is essential to delineate between actual PSAR content guidance and other information.
5 B.3.2 The second sentence of section B.3.3. states: Please delete or rewrite B.3.2 and B.3.3 to address the and The staff notes that a minimally acceptable PRA would not points raised in the comment.
B.3.3 support full implementation of the LMP methodology at the CP stage because it may not address non-core radiological sources, low power and shutdown POSs, and all internal and external Action required as noted in Comment 1 to differentiate hazards groups. in the guidance between 1) information on how to perform the CP PRA and 2) what information regarding First, this text provides guidance on performing the PRA analysis, not what the CP PRA is needed for inclusion in the PSAR.
information from the PRA analysis should be documented in the SAR.
Second, this language is in conflict with B.3.2 whose text states: the CP PRA scope should address all radiological sources, all hazards, and all POSs.
Third, the idea that a PRA would address or include all these items is incorrect.
Things may be screened out or addressed deterministically and not necessarily included in the PRA. LMP is a risk-informed and not risk based methodology.
In addition, the phrase full implementation of LMP is not appropriate because there are no criteria to decide which are deemed full. A CP application either applies the methodology in NEI 18-04 or does not. If the CP application deviates from the methodology that must be documented.
Finally, B.3.2 states 1. Identify all radiological sources, POSs, and hazards by performing a comprehensive and systematic search. and 2. Disposition the search results by a combination of PRA logic modeling, acceptable screening methods, risk-informed supplemental evaluations, and crediting design-basis hazard levels (DBHLs). This text also provides guidance on performing the PRA analysis, not what information from the PRA analysis should be documented in the SAR.
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NEI Consolidated Comments on NRC DG-1404 Rev 1 Attachment 1 October 10, 2023 DG1404 Appendix B Comment # Location Comment Proposed Change 6 B.3.4 The acronym SR is defined as Supporting Requirements. However, this It is an error-likely situation to define SR as two different acronym is defined as safety-related throughout DG-1404 including terms. Industry would prefer to keep SR as safety-elsewhere in Appendix B (example: Item B.3.7) and in other ARCAP related and not use an acronym for supporting documents. requirements.
7 B.3.6 It is unclear if B.3.6 is intended to apply to the PSAR or to internal Action required as noted in Comment 1 to differentiate documentation (plant records). in the guidance between the information regarding the CP PRA that is needed for inclusion in the PSAR, and If it is the former (PSAR), the guidance goes beyond current documentation other information.
requirements and is a level of detail that is inappropriate for the PSAR.
If it is the latter (plant records), the information should be sufficiently differentiated to ensure regulatory predictability and certainty.
8 B.4.2 The last sentence of the guidance text states: Consistent with Staff Position Please remove this statement and limit the expectations C.2.1 in RG 1.247, all HLRs for a given PRA element should be met. This to meet technical requirements to supporting statement is inappropriate because self-assessments and peer reviews under the requirements.
NEI guidance generally do not include meeting HLR requirements. Self-assessments and peer reviews only involve meeting the supporting requirements.
This is the case for both non-LWRs and LWR applications of the NEI PRA peer review guidelines.
5
NEI Consolidated Comments on NRC DG-1404 Rev 1 Attachment 1 October 10, 2023 9 B.5.2 The guidance text states: In presenting the expectations for meeting the technical requirements in Table B-2 and in Table B-3, The staff has applied the process provided in Section 3 of the ASME/ANS the NRC should note that the selection of non-LWR PRA standard and the results are presented in Tables B-2 and B- requirements for inclusion in the CP PRA are 3, which follow the main body of this appendix. The CP applicant may use dependent on the level of detail of design and Tables B-2 and B-3 to establish the acceptability of the PRA level of detail. operational information included in the CP application.
Alternatively, the CP applicant may perform a separate analysis using the The requested self-assessments should be limited to process provided in Section 3 of the ASME/ANS non-LWR PRA standard and those technical requirements that can be addressed justify any deviations from or alternatives to Tables B-2 and B-3. with the design and operational information included in the CP application.
Table B-2 covers all the technical requirements for an internal event at power PRA and suggests that all the requirements should be met for a minimally acceptable PRA for CP application. Table B-3 addresses the remaining requirements for PRAs with an expanded scope. The expectation raised in these tables about standard compliance is unreasonable because it is unlikely that there would be sufficient design and operational information included in the CP application to support the PRA scope that would be required to meet all these requirements.
It is made clear in Section 1.3 of the non-LWR standard that the selection of the scope and the technical requirements to support PRAs in different life cycle stages is dependent on the level of design and site information that is available at that life cycle stage. As stated in Section 3.1(a) of the standard:
The scope and level of detail of the PRA is then selected based on the design and site characteristics and the state of design and site information available to support the PRA.
It is expected that most CP applications will not have sufficient information on the design and operational features of the plant to be able to support a PRA scope and level of detail that would be capable of addressing all these requirements. Although the second paragraph provides a means of proposing an alternative scope of requirements and capability categories, the overall impression is that NRC is expecting a scope and level of detail that is likely to exceed that which can be supported by the level of design and operational information that will be included in the CP application. The problem is this issue should not be viewed as a case-by-case exception, but rather a generic problem with PRAs to support CP applications.
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NEI Consolidated Comments on NRC DG-1404 Rev 1 Attachment 1 October 10, 2023 DG1404 Appendix B Comment # Location Comment Proposed Change 10 B.7 The text in sections noted below applies to how to document PRA archival Action required as noted in Comment 1 to differentiate information (not in the PSAR) rather than how to document the PRA in the in the guidance between the information regarding the PSAR. CP PRA that is needed for inclusion in the PSAR, and other information.
B.7.2 B.7.3 11 B.7.1 The text states NEI 21-07, Revision 1, as endorsed with additions and Given this point, NRC needs to clarify that none of the clarifications in the main body of this RG, provides an acceptable approach other guidance in Appendix B applies to documentation and format for providing CP PRA submittal information. of the CP PRA in the PSAR, and that the guidance in NEI 21-07, Revision 1, is sufficient to cover all of PRA NEI emphatically agrees with the comment.
documentation requirements. See Comment #1 12 B.8.3 The guidance text states, Consistent with NEI 21-07, Revision 1, Section 2.1.1, Please delete B.8.3.
page 24, the CP applicant should describe its ultimate intended approach for qualifying the PRA.
This guidance is completely unnecessary. As Appendix B makes clear, the point is completely covered in NEI 21-07 on p. 24; there is no need to repeat it. Moreover, it is already covered by the general statement in B.7.1.
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