ML19226A207

Staff Response to Nuclear Energy Institutes Proposed Technical Specification Changes Associated with the Use of Newly-Developed Methods for Risk-Informed Completion Times

ML19226A207
Person / Time
Issue date:	02/02/2022
From:	Weerakkod S NRC/NRR/DRA
To:	Mike Franovich NRC/NRR/DRA
Mehta S
References
Download: ML19226A207 (16)

Text

February 2, 2022 MEMORANDUM TO:

Michael X. Franovich, Director Division of Risk Assessment Office of Nuclear Reactor Regulation FROM:

Sunil D. Weerakkody, Senior Level Advisor Division of Risk Assessment Office of Nuclear Reactor Regulation

SUBJECT:

STAFF RESPONSE TO NUCLEAR ENERGY INSTITUTES PROPOSED TECHNICAL SPECIFICATION CHANGES ASSOCIATED WITH THE USE OF NEWLY DEVELOPED METHODS FOR RISK-INFORMED COMPLETION TIMES I.

BACKGROUND AND

SUMMARY

On February 8, 2019 (ADAMS Accession No. ML21154A174), the Nuclear Energy Institute (NEI) proposed a change to the Administrative Technical Specification (TS) provided in the U.S.

Nuclear Regulatory Commission (NRC) staffs safety evaluation for TSTF-505 (ADAMS Accession No. ML18267A259). The purpose of this memorandum is to provide you with my recommendation for TS language that may provide for a possible path forward for staff to consider in addressing the issues reflected in the NEIs proposal mentioned above. In this memo, I have articulated some regulatory history and precedence, which I believe are supportive of my recommendation. I note that there are some NRC staff differing views regarding my recommendation. Those differing views are summarized in a non-concurrence associated with this memorandum, NCP-2020-011 (ADAMS Accession No. ML21112A356).

Furthermore, my recommendations, as reflected in this memo, should not be construed as de facto guidance for staff in their ongoing or future reviews of Technical Specifications Task Force (TSTF) Travelers and license amendment requests, as such guidance should ultimately be laid out in an established process, such as through an NRR Office Instruction.

I understand that the TSTF will be formally submitting a traveler for NRC review, in the near term, to address this issue using the traveler review process (as addressed in LIC 600, Standard Technical Specifications Change Traveler Review and Adoption Process). My recommendation is for considering the enclosed proposed TSs for the NRC staffs review of the traveler or when evaluating any future license amendment requests (LARs) relating to TSTF 505, Provide Risk-Informed Extended Completion Times - RITS Initiative 4B.

CONTACT: Sunil Weerakkody, NRR/DRA 301-415-2870 Signed by Weerak on 02/02/22

M. Franovich The proposed TS language in the enclosure of this memo, if adopted via a formal regulatory process, would enable licensees to incorporate newly developed methods (NDM) into probabilistic risk assessment (PRA) models, prior to receiving formal NRC staff review and approval of those methods. I reviewed NEIs proposal and consulted with multiple NRC staff members in Division of Risk Assessment (DRA), Division of Reactor Oversight, Division of Operating Reactor Licensing, and the Technical Specifications Branch within the Division of Safety Systems. Then, in consultation with the staff mentioned above, I prepared the TSs for the Risk Informed Completion Times program (RICT) provided in the enclosure. In evaluating NEIs proposal and in preparing the proposed TS language, I and my peers considered the following: (1) potential impacts to public health and safety, (2) other regulations that provide for licensee-controlled change processes, (3) previously established staff positions, and (4) the NRCs Principles of Good Regulation (POGR).

For the reasons described below, I am recommending consideration of the proposed TS for the RICT program provided in the enclosure, which I believe provides for an efficient approach for a licensee to determine when the licensee may use a NDM without NRC approval. The proposed TS also identifies thresholds, which if exceeded, will prompt licensees to seek prior NRC approval of an NDM before using it in a PRA model.

In developing the proposed TS language in the enclosure, I along with the staff mentioned above, considered and used staff positions in the recently issued RG 1.200, Revision 3, which endorses, with appropriate clarifications, NEI 17-07, Revision 2, Performance of PRA Peer Reviews Using the ASME/ANS PRA Standard, issued August 2019 (ADAMS Accession No. ML19241A615), and several sections of the Pressurized-Water Reactor Owners Group (PWROG)-19027-NP, Revision 2, Newly Developed Method Requirements and Peer Review, issued July 2020 (ADAMS Accession No. ML20213C660). If the proposed TS is approved, licensees that choose to adopt language similar to that in the enclosure will be required to transmit their NDM peer review implementation reports to the NRC and incorporate those NDMs into their PRA models.

I, along with my peers, have drafted an Office Instruction (OI) that would enable NRC to review any NDM peer review related reports, entitled, Guidance for Assessing NDM and NDM Implementation Reports, which is available in ADAMS (ADAMS Accession No. ML20252A215). Once the staff has the opportunity to gain some lessons learned/best practices associated with these types of reviews, the staff will then pursue finalizing and issuing the OI in accordance with the established process for use to guide the staffs review of the licensees peer review implementation reports.

With this proposal, if the NRR subject matter expert (SME) staff concludes, based on its review of the NDM implementation report, that the NDM is unlikely to meet the NDM peer review requirements stated in PWROG-19027-NP and, therefore, may have violated TS requirements, NRR/DRA will inform the regional inspectors and request they make the licensees application of that NDM a priority in the inspection sampling. If the inspectors require additional support, HQ SMEs and the HQ senior reactor analyst will offer the necessary SME and PRA support. The staff made some modifications to the proposed TS in the enclosure based on some of the comments provided in a non-concurrence documented in ADAMS Package Accession No. ML21112A354.

The burden attributed to the proposed TS for the NRC renewal request to the Office of Management and Budget (OMB) for 10 CFR Part 50 has been approved by OMB.

M. Franovich 1F This memorandum is organized as follows:

Section II briefly describes the NEIs proposal for TS language transmitted to the NRC in 2018.

Section III describes Commission discussions on PRA quality and establishment and the evolution of the peer review process.

Section IV discusses the roles of PWROG-19027-NP and NEI 17-07 with respect to NDMs.

Section V compares key attributes of the TS language in Enclosure 1 with alternatives (i.e., the NEI proposal in 2018 and Revision 2 of the safety evaluation for TSTF-505).

Section VI discusses how the NRC staffs recommendation maintains public health and safety and is consistent with the POGR.

Section VII provides the NRC staffs recommendation.

II.

NEI PROPOSAL FOR TECHNICAL SPECIFICATION LANGUAGE When the NRC issued the safety evaluation for Revision 2 of TSTF-505, entitled, Final Revised Model Safety Evaluation by the Office of Nuclear Reactor Regulation Technical Specifications Task Force Traveler TSTF-505, Revision 2, Provide Risk-Informed Extended Completion TimesRITSF Initiative 4B, dated November 21, 2018 (ADAMS Accession No. ML18267A259), the staff evaluated TS changes on a non-plant-specific basis, including the following model administrative TS 5.5.15/5.5.18.e associated with changes to risk assessment approaches and methods.

The risk assessment approaches and methods shall be acceptable to the NRC.

The plant PRA shall be based on the as-built, as-operated, and maintained plant; and reflect the operating experience at the plant, as specified in Regulatory Guide 1.200, Revision [2]. Methods to assess the risk from extending the Completion Times must be PRA methods approved for use with this program, or other methods approved [emphasis added] by the NRC for generic use; and any change in the PRA methods to assess risk that are outside these approval boundaries require prior NRC approval.

Industry expressed concerns with the above language, primarily because, when adopted, it would require licensees to request prior review and approval of any changes in PRA methods.

Therefore, NEI transmitted a proposal (ADAMS Package Accession No. ML21154A176) that would enable licensees to use NDMs in PRA models, after an independent peer review, without prior NRC approval. Rather, a licensee would provide a peer reviewers report to the NRC for review, following each PRA upgrade involving an NDM at least 60 days before using the upgraded PRA to calculate a risk-informed completion time in accordance with their proposed TSs.

M. Franovich III.

COMMISSION DISCUSSIONS ON PRA QUALITY AND ESTABLISHMENT OF THE PRA PEER REVIEW PROCESS III.A Commission Discussions on PRA Quality Discussions about the acceptability of PRA quality to support risk-informed regulatory activities started in the late 1990s with the NRC rulemaking on Title 10 of the Code of Federal Regulations (10 CFR) 50.69, Risk-informed categorization and treatment of structures, systems and components for nuclear power reactors. In SECY-99-256, Rulemaking Plan for Risk-Informing Special Treatment Requirements, dated October 29, 1999, the staff sought to obtain the Commissions approval of a rulemaking plan and issuance of an advanced notice of proposed rulemaking for risk-informing special treatment requirements. On January 30, 2000, in Staff Requirements Memorandum (SRM)-99-256, the Commission approved publication of the advanced notice of proposed rulemaking for risk-informing special treatment requirements and approved the rulemaking plan subject to the comments provided in the SRM. As noted in an excerpt from SECY-99-256 below, the staff informed the Commission about options available to address the issues on PRA quality. Specifically, Section 7.0 of that SECY described several impacts on licensees that wish to implement a risk-informed approach to special treatment. The first of the four items in Section 7.0 in that SECY stated the following:

Licensees that wish to implement a risk-informed approach to special treatment will, at a minimum, incur the following impacts: The licensee will need to address PRA completeness and quality issues. At a minimum licensees will need to have a PRA that reflects the current plant configuration, is sufficiently complete for the intended application, meets some quality standard (this is not yet defined and could range from an industry peer review to requiring the PRA to be reviewed by the staff), and is kept current [emphasis added]. Depending on the state of the licensees PRA, this activity could involve a significant commitment in resources.

In COMNJD-03-0002, Stabilizing the PRA Quality Expectations and Requirements, dated September 8, 2003 (ADAMS Accession No. ML033530285), the then-Chairman of the NRC expressed his view that the NRC must clarify Commission policy and expectations of the role, applicability, and characteristics of PRA quality for the NRCs risk-informed regulatory decisionmaking. The Chairman indicated that a policy decision is needed to stabilize the PRA quality expectations and requirements and enable its broader and more predictable use in safety related applications. The Chairman asked for consideration and approval of an enclosed proposal, entitled Regulatory Decisionmaking and PRA Quality, which presented a path for defining acceptable means for achieving the requisite PRA quality for regulatory purposes. On December 18, 2003, the Commission issued SRM-COMNJD-03-002 (ADAMS Accession No. ML033520457) and approved implementation of a phased approach to achieving an appropriate quality for PRAs for the NRCs risk-informed regulatory decisionmaking.

Consequently, the NRC staff developed SECY-04-0118, Plan for the Implementation of the Commissions Phased Approach to Probabilistic Risk Assessment Quality, dated July 13, 2004 (ADAMS Accession No. ML041530055). In that SECY, the staff provided the Commission with the action plan for the implementation of the phased approach to PRA quality, informed the Commission about anticipated staff resource impacts, and requested Commission direction and additional guidance on policy issues related to the implementation of the plan. The plan in SECY-04-0118 articulated how the staff would rely on an industry peer review process, an industry consensus standard, and associated regulatory guidance to assure PRA quality in a

M. Franovich manner that meets Commission expectations, with some important caveats. For example, the subject SECY noted the following:

In Phase 2 the staff review of the base PRA is performed in a more efficient way by virtue of a peer review of those parts of the baseline PRA necessary to support the application having been performed in accordance with RG 1.200.

The staff review of the baseline PRA is focused on those parts of the PRA which the peer review has identified as not having been performed in accordance with the appropriate standard, and that are significant to the application, and on those key assumptions and sources of model uncertainty that are significant to the decision [emphasis added]. Thus, the review is performed in a more formal and systematic manner.

When the NRC promulgated 10 CFR 50.69 in 2004, the final rule included requirements related to peer reviews. Specifically, in accordance with 10 CFR 50.69(b)(2)(iii), an application must include Results of the PRA review process conducted to meet § 50.69(c)(1). To approve the application and grant the LAR, the NRC must find that the application meets several approval criteria, including in 10 CFR 50.69(c)(1)(i) requiring the structure, system, and component categorization process to do the following:

Consider results and insights from the plant-specific PRA. This PRA must, at a minimum, model severe accident scenarios resulting from internal initiating events occurring at full power operation. The PRA must be of sufficient quality and level of detail to support the categorization process and must be subjected to a peer review process assessed against a standard or set of acceptance criteria that is endorsed by the NRC.

As stated in Volume 69 of the Federal Register (FR), page 68011 (69 FR 68011; November 22, 2004), during the rulemaking process for the risk-informed categorization and treatment of structures, systems and components for nuclear power reactors, the Commission requested stakeholder comment on whether the NRC should amend the requirements in

§50.69(c) to require a level 2 internal and external initiating events, all-mode, peer-reviewed PRA that must be submitted to, and reviewed by, the NRC. After consideration of public comments, the Commission concluded that the PRA requirements in the proposed rule are sufficient for that application, while noting the NRCs usage of the peer review process:

There are several other features to the regulatory framework that also contribute to ensuring sound PRA is used such as requiring aspects of the categorization process to be reviewed and approved before implementation, requiring the PRA to be peer reviewed, Integrated Decision-Making Panel (IDP) requirements, provisions for addressing all modes and events regardless of whether in the PRA, feedback and update requirements, and supporting standards.

In that same notice, the Commission also explained the staffs role relative to a peer review:

Before a licensee may implement § 50.69, the NRC must approve the categorization process through a license amendment. This is necessary because of the importance of the PRA and categorization process to successful implementation of the rule. This review and approval of the categorization process is a one-time, process approval (i.e., the approval is not restricted to a

M. Franovich set of systems or structures, and can be applied to any system or structure in the plant and the licensee is not required to come back to the NRC for review of the categorization process provided that licensee remains within the scope of the NRC's safety evaluation). The NRC's review of the § 50.69 submittal will determine whether § 50.69 requirements are satisfied and consider the adequacy of the PRA; focusing on the results of the peer review and the actions taken by the licensee to address any peer review findings [emphasis added]. The Commission has determined that a focused NRC review of the PRA is necessary because there are key assumptions and modeling parameters that can have a significant impact on the results so that NRC review of their adequacy for this application is considered necessary to verify that the overall categorization process will yield acceptable decisions.

In summary, for a 10 CFR 50.69 application, the Commission requires the NRC to review the results of the peer review before granting a 10 CFR 50.69 LAR, because key assumptions and modeling parameters can have a significant impact and must therefore be checked for adequacy.

I, along with my peers, note that just like with the original PRA, an NDM can introduce key assumptions and modeling parameters that can have a significant impact on the results.

However, for a licensee to have applied for and to have received an approved risk-informed completion time (RICT) program, the licensee would have already undergone a peer review of its PRA; and the staff would have already performed a focused review of the results of that peer review and found the licensees use of the PRA to be sufficient for the intended purposes. As such, the staff review would have already taken place before the staff approves the LAR.

Turning to NDMs and the proposed TSs provided in the enclosure, I and my peers suggest that a prior review and approval through a licensing action is not needed. Our rationale for this approach is that the licensee already would have demonstrated its abilities to appropriately identify and address key assumptions and to use proper modeling from the NRC approval on the RICT programs, as described above. Further, the staff also reviews the licensees PRA configuration control program prior to approval of the LAR. This configuration control program maintains the licensees abilities to make good assumptions and to use good models. As a result, the NRC staff would have already verified that the licensees overall processes yield acceptable assumptions and models. This provides additional confidence that the licensee will continue to apply previously NRC-approved approaches when the licensee uses NDMs.

Therefore, I believe that there is a diminished need for the NRC to perform a focused review of the results of the peer review before allowing a licensee to use an NDM. Instead, the NRC could rely on the licensees compliance with the RICT program elements defined in the proposed TS to provide overall control of NDMs as well as scrutable, inspectable standards that the licensee will use.

III.B Establishment and Evolution of the Peer Review ProcessSection III.A articulates summarizes key Commission communications relating to PRA quality and inception of the peer review process. This section summarizes how external entities, i.e.,

the Nuclear Energy Institute and the ASME/ANS standard committee generated important documents to enable implementation of the peer review process. While Commission deliberations on PRA quality continued, so did industry-initiated development of guidance to establish the peer review process. For example, in March 2000, the NEI published Revision A3 of NEI 00-02, Probabilistic Risk Assessment (PRA) Peer Review Process Guidance (ADAMS Accession No. ML003728023), which provided guidance material for use in conducting and

M. Franovich documenting a PRA peer review. The material in NEI 00-02 was adopted from the review process originally developed and used by the Boiling Water Reactor Owners Group (BWROG),

which the BWROG provided to industry through the NEI Risk Based Applications Task Force (RBATF). Adoption of this material was initially done as a joint technical program between the Westinghouse Owners Group and the Babcock & Wilcox Company Owners Group, and technical information exchanges have taken place, both directly and through the NEI RBATF, with input from the Combustion Engineering Owners Group and the BWROG. Development of NEI 00-02 and publication of American Society of Mechanical Engineers (ASME) RA-S-2002, Standard for Probabilistic Risk Assessment for Nuclear Power Plant Applications, dated April 5, 2002, and ASME RA-Sa-2003, Addenda to ASME RA-S-2002, dated December 5, 2003, were instrumental in the NRC staffs ability to establish a peer review process in accordance with PRA quality expectations and requirements articulated in the staff action plan included as an attachment to SECY-04-0118.

In addition to the industry guidance (NEI 00-002) and the ASME/American Nuclear Society (ANS) Probabilistic Safety Assessment (PSA) Standard, a third critical document to establish the peer review process was regulatory guidance. The NRC published the initial guidance for-trial version of RG 1.200, entitled An Approach for Determining the Technical Adequacy of Probabilistic Risk Assessment Results for Risk-Informed Activities, in February 2004. That regulatory guidance enabled the staff to establish its expectations of quality by documenting staff positions with respect to PRA review requirements in the ASME/ANS PSA Standard.

Consequently, the staff used RG 1.200 to clarify its position, which included, in some instances, disagreeing with the requirements in the standard.

The NRC has been engaged in the development of the NEIs peer review guidance since the early 2000s. NEI 05-04, Revision 2, Process for Performing Internal Events PRA Peer Reviews Using the ASME/ANS PRA Standard, issued November 2008 (ADAMS Accession No. ML083430462), and NEI 07-12, Revision 1, Fire Probabilistic Risk Assessment (FPRA)

Peer Review Process Guidelines, issued August 2010 (ADAMS Accession No. ML102230070),

are important benchmarks in the industry peer review guidance development process. Issuance of Revision 3 of RG 1.200 and Revision 2 of NEI 17-07 are the latest advancements in the process.

IV.

DEVELOPMENT OF THE DEFINITION OF NEWLY DEVELOPED METHOD, PEER REVIEW REQUIREMENTS, AND UPDATE PEER REVIEW PROCESS Most of the NRC staffs concerns about the industry peer review processs capability to adequately address new methods emerged during its reviews of LARs pertaining to the adoption of National Fire Protection Association (NFPA) 805, Performance-Based Standard for Fire Protection for Light Water Reactor Electric Generating Plants. In some instances, the NRC staff reviewers found that licensees had used assumptions and approximations for which the bases were incorrect or not clearly articulated. Lack of criteria to determine the acceptability of NDMs in either ASME/ANS RA-Sa-2009, Standard for Level 1/Large Early Release Frequency Probabilistic Risk Assessment for Nuclear Power Plant Applications, or in RG 1.200 exacerbated the problem.

This situation eroded the staffs confidence in the ability of the industry peer review process to appropriately handle new methods. The staffs sensitivity to this issue arose because of the increasing number of LARs that, when approved, would grant licensees the flexibility to self-approve changes using PRA insights or inputs. This sensitivity increased with the Risk-Informed Technical Specification (RITS) 4b initiative, Risk-Managed Technical

M. Franovich Specifications. This is because RITS 4b uses numerical outputs from PRA models to control the duration for which licensees may operate a plant with specific equipment degraded or inoperable.

To address the gap related to requirements for determining the acceptability of new methods, the PWROG took the initiative to develop review requirements for NDMs (use of the word requirements here is compatible with its use in the ASME/ANS PSA Standard). Since industry and the NRC staff lacked alignment on what constituted an NDM, that initiative included generating a definition for NDM and other associated terms to establish a common understanding between the NRC staff and industrys PRA peer review community.

Industry held a number of workshops to generate these review requirements and associated definitions. The NRC staff observed these workshops as well as three pilot peer reviews during which industry peer reviewers used the NDM peer review requirements. The NRC staff then issued its findings in United States Regulatory Commission Audit on Newly Developed Method Peer Review GuidancePilot Peer Observations Report, dated January 22, 2020 (ADAMS Accession No. ML19311C785). The PWROG submitted PWROG-19027-NP for NRC staff review. As part of the review process, the NRC provided comments to industry on the definition of NDM and the review requirements. The NRC endorsed the following sections of PWROG-19027-NP in Revision 3 of RG 1.200:

requirements for the peer review of NDMs provided in Tables 1-7.2-2 through 1-7.2-7 (see Regulatory Positions C.2.2.2 through C.2.2.4 of RG 1.200, Revision 3),

process for determining whether a change to a PRA is classified as PRA maintenance or a PRA upgrade (see Appendix C of RG 1.200, Revision 3), and

definitions related to NDMs, PRA maintenance, and PRA upgrade (see the glossary in RG 1.200, Revision 3).

To address the possibility for licensees to use NDMs after a peer review but before receiving approval through a formal process such as a topical report or an LAR, the peer review process also had to be enhanced. Therefore, NEI took the initiative to update peer review guidance, specifically, to prepare NEI 17-07. In addition to several other changes, NEI 17-07 enhanced the industry peer review guidance by including information on how to review NDMs. Throughout that update process, the NRC staff and the NEI discussed the NRC staffs comments during multiple public meetings (e.g., see ADAMS Accession Nos. ML18250A251, ML18331A370, ML18352A750, ML19141A130).

The proposed TSs provided in the enclosure requires a licensee to use the peer review process in NEI 17-07, Revision 2, Performance of PRA Peer Reviews Using the ASME/ANS PRA Standard. The peer review report described in Section 9.1 of NEI 17-07, Revision 2, for both the acceptability and implementation of the newly developed method must be retained.

Regulatory Position C.2.2 in RG 1.200, Revision 3, provided guidance on the performance of PRA peer reviews and endorsed NEI 17-07, Revision 2, in its entirety as a means of satisfying the peer review requirements in the ASME/ANS RA-Sa-2009, as endorsed by the NRC in that RG with staff exceptions and clarifications.

M. Franovich V.

COMPARISON OF KEY ATTRIBUTES OF ALTERNATIVE TECHNICAL SPECIFICATIONS Given the established peer review process and NRC positions adopted in RG 1.200, Revision 3, the NRC staff held a large number of internal discussions and multiple public meetings to discuss the NEIs proposal to modify the TS (see ADAMS Accession Nos. ML18033A769, ML18250A251, ML19141A130, ML19238A288, ML19254B936, ML20031E670). In considering these discussions and deliberations among cognizant staff in the DRA and the Technical Specifications Branch of the Division of Safety Systems, I, along with my peers, created a comparison between key attributes of the TS in the NEI proposal; the safety evaluation of TSTF-505, Revision 2; and the proposed TSs in the enclosure.

The table below compares key attributes between the TSs administrative controls program provided in Revision 2 of TSTF-505, the NEI proposal, and the staffs proposal in the enclosure, followed by a discussion of these attributes in detail.

Attribute Section 2.2.2.e of the Safety Evaluation on TSTF-505, Revision 2 (ML18267A259)

NEI Proposal (ML21154A174)

Proposed TSs Provided in the enclosure to This Memorandum A. Requires licensee to seek prior NRC approval to use PRA or non-PRA techniques (such as FIVE, Seismic Margins Approach, and PRA) other than those stated in licensees LAR YES YES YES B. Requires prior NRC approval to use NDMs YES NO NO C. Specifies the applicable RG Requires using Revision 2 of RG 1.200 Requires using Revision 2 of RG 1.200 Requires use of Revision 3 of RG 1.200 D. Provides evaluation criteria for NDMs that, if not met, would require prior NRC approval N/A (all NDMs require prior NRC approval)

NO YES A.

Changes to Techniques such as Fire PRA and Seismic PRA

All three versions of the TSs require the licensee to seek prior NRC approval to use PRA or non-PRA techniques in the TSs other than those approved by the NRC.

B.

Changes to PRA Methods

Revision 2 of TSTF-505 requires licensees to receive prior NRC approval to use methods that have not been approved by the NRC.

The NEI proposal, if endorsed via TSTF traveler, etc., allows licensees to follow the

M. Franovich staff-endorsed industry peer review process to use NDMs in the RICT program without prior NRC approval.

The NRC staff proposal, if endorsed via an appropriate process, allows licensees to use the staff-endorsed industry peer review process to use NDMs in the RICT program without prior NRC approval, but only if they maintain an NRC-approved PRA configuration control program. However, if any applicable requirements in Tables 1-7.2-2 through 1-7.2-7 f of PWROG-19027-NP, Revision 2, are not met, use of the NDM requires prior NRC approval.

C.

Use of NRC Guidance Documents or Endorsed Industry Guidance

Revision 2 of TSTF-505 uses Revision 2 of RG 1.200, issued March 2009 (ADAMS Accession No. ML090410014), which in turn endorses ASME/ANS RA-Sa-2009 and a number of NEI documents (e.g., NEI 00-02, NEI 05-04, NEI 07-12) that provide peer review guidance.

The NEI proposal uses Revision 2 of RG 1.200, which in turn endorses ASME/ANS-RA-Sa-2009 and a number of NEI documents. In addition, it uses Revision 2 of NEI 17-07 and PWROG-19027-NP. It also refers to the pending update (Revision 3) to RG 1.200.

The NRC staff proposal uses only Revision 3 of RG 1.200, which continues to refer to ASME/ANS-RA-Sa-2009, Revision 2 of NEI 17-07, and several sections of Revision 2 of PWROG-19027-NP. Positions adopted in RG 1.200, Revision 3, provide guidance for the peer review process and review requirements for the NDMs. Use of the proposed TSs in the enclosure requires incorporation of Revision 3 of RG 1.200 into the licensing basis. Revision 3 of RG 1.200 includes definitions for a subset of terms important for NDM implementation.

D.

Threshold Criteria for NRC Staff Approval of Newly Developed Methods

Revision 2 of TSTF-505 requires licensees to receive prior NRC approval to use all NDMs for RICTs.

The NEI proposal does not have explicit threshold criteria. It enables licensee use of all NDMs in the RICT program after they go through the industry peer review process.

The NRC staff proposal contains criteria that, if not met, would require licensees to obtain prior NRC staff approval for a subset of NDMs.

VI.

DISCUSSION The sections below address the proposed TSs provided in the enclosure, with regard to the following four key attributes: (1) impacts to public health and safety, (2) consistency with other regulations that provide for licensee-controlled change processes, (3) the NRCs established staff positions as reflected in RG 1.200, Revision 2, with respect to peer review of PRA methods, and (4) the NRCs POGR (ADAMS Accession No. ML14135A076). When appropriate, the staff compared its proposal against the alternatives in terms of these attributes.

M. Franovich A.

Maintaining Safety Before granting the operating license to a licensee under 10 CFR 50.57(a)(3), the Commission concludes that there is reasonable assurance that the activities authorized by the operating license can be conducted without endangering public health and safety. The proposed TS in the enclosure, if incorporated into a licensing basis, would grant licensees the flexibility to use NDMs after the performance of industry peer reviews following the NRC-endorsed process.

Since (1) the peer reviewers will be required to use review requirements (documented in Revision 2 of PWROG-19027-NP) that the NRC staff endorsed in RG 1.200, and licensees must also use a process that has been endorsed by the NRC staff in RG 1.200 (documented in Revision 2 of NEI 17-07, and (2) any NDMs that do not meet the established criteria will require NRC staff approval before their use, in my professional opinion, believe that the language in the TS administrative controls, as proposed in the enclosure, provides reasonable assurance that the applicant will comply with the regulations and that public health and safety will not be endangered.

B.

Consistency with Change Processes in Other Regulations Several NRC regulations allow licensees to make changes to their programs without prior NRC approval if the changes are performed using NRC-endorsed technical guidance and process requirements. For example, under 10 CFR 50.54(q), licensees may make changes to their emergency plans as long as the changes do not reduce the effectiveness of the plan and the plan continues to meet the requirements in Appendix E, Emergency Planning and Preparedness for Production and Utilization Facilities, to 10 CFR Part 50, Domestic licensing of production and utilization facilities, and in 10 CFR 50.47(b). Under 10 CFR 50.59, licensees may make changes without prior NRC approval if the specific criteria in the regulations have been met. To address this gap, in the NEI-proposed change process, and the proposed TSs provided in the enclosure includes the following language:

The NDMs used in the licensees PRA model must meet all applicable review requirements in Tables 1-7.2-2 through 1-7.2-7 of Pressurized-Water Reactor Owners Group (PWROG)-19027-NP, Revision 2, Newly Developed Method Requirements and Peer Review, issued July 2020. The licensee must use the peer review process in Nuclear Energy Institute (NEI) 17-07, Revision 2, Performance of PRA Peer Reviews Using the ASME/ANS PRA Standard, issued August 2019. All peer review findings on NDM must be closed using an NRC-endorsed process. If any applicable requirements in Tables 1-7.2-2 through 1-7.2-7 f of PWROG-19027-NP, Revision 2, are not met, use of the NDM requires prior NRC approval. The peer review report described in Section 9.1 of NEI 17-07, Revision 2, for both the acceptability and implementation of the NDM must be retained.

In situations where the NRC has afforded licensees the flexibility to make changes using various risk-informed initiatives, the NRC has enhanced the oversight function to ensure that licensees are following NRC requirements and guidance appropriately. For example, the NRC uses an oversight process to inspect a sample of 10 CFR 50.59 evaluations prepared by licensees. In order to accomplish that oversight function effectively for TSTF-505 as well as for several other risk-informed initiatives, the NRC staff has revised four inspection procedures (IPs):

IP 71111.13, Maintenance Risk Assessments and Emergent Work Control, dated October 5, 2020; IP 71111.22, Surveillance Testing, dated November 20, 2020; IP 71111.12, Maintenance Effectiveness, dated March 31, 2021; and IP 71111.18, Plant Modifications,

M. Franovich dated March 31, 2021. These revisions will, in fact, improve our ability to oversee TSTF-505 implementation.

With respect to NDMs, upon receiving an NDM implementation report (as required by the TS),

the NRC Headquarters (HQ) SME staff will assess the acceptability of NDMs in accordance with the NRR OI (Draft available in ADAMS ML20252A215). This practice has some similarity to that established with respect to the 10 CFR 50.59 process in that the NRC HQ staff receives periodic reports on 10 CFR 50.59 evaluations that licensees have performed. If the SMEs conclude that a particular NDM may not be acceptable, that concern will be communicated to the regional staff. The NRC will also inform the licensee about the concern in a publicly available document, consistent with the draft NRR OI, once it is approved and issued consistent with our process. The document will articulate the concern using the NDM review requirements in PWROG-19027-NP (incorporated in the licensees administrative TS). In my professional opinion, this approach will enable a regional staff member to engage with the licensee, using samples from the recently revised IP 71111.13, effectively. If the inspectors require additional support, HQ SMEs, the HQ senior reactor analyst, and the regional senior reactor analysts will offer the necessary SME and PRA support.

C.

Consistency with Prior NRC Staff PositionsSection III of this memorandum details how the industry peer review process was established to ensure PRA quality. Revision 2 of RG 1.200 is the current NRC staff guidance that refers to the use of the industry peer review process to establish and maintain PRA quality, including the purview of peer review teams to review methods used by the licensees.

The staff developed RG 1.200, like the majority of other NRC RGs, through an open, deliberative process. Section A, Introduction, of RG 1.200 states that When used in support of an application, it will obviate the need for an in-depth review of the base PRA by NRC reviewers, allowing them to focus their review on key assumptions and areas identified by peer reviewers as being of concern and relevant to the application.

In several instances, RG 1.200, Revision 2, states that the peer reviewer can review methods:

Table 16 in RG 1.200 includes review of PRA methods and review of applications of methods among the 11 items listed as elements of the peer review process.

Section 2.2 of RG 1.200 states that In addition to reviewing the methods used in the PRA, the peer review determines whether the methods were applied correctly.

In summary, RG 1.200 includes the review of NDMs within the peer reviewers scope but emphasizes the need to review key assumptions that, for example, support NDMs.

Based on this information, in my professional opinion, I believe that allowing licensees to use NDMs with no findings after the completion of an industry peer review following the NRC-endorsed process is consistent with prior NRC staff positions.

M. Franovich D.

Principles of Good Regulation With respect to independence, the POGR state the following:

Nothing but the highest possible standards of ethical performance and professionalism should influence regulation. However, independence does not imply isolation. All available facts and opinions must be sought openly from licensees and other interested members of the public. The many and possibly conflicting public interests involved must be considered. Final decisions must be based on objective, unbiased assessments of all information, and must be documented with reasons explicitly stated.

The NRC staff has conducted multiple public discussions (e.g., ADAMS Accession Nos. ML18250A251, ML18331A370, ML18352A750, ML19141A130) to review and provide feedback on NEI 17-07, which describes the peer review process relating to NDMs. The staff also observed several meetings led by the PWROG that served to develop the definition of NDMs and the high-level and supporting requirements that will be used to review NDMs. The NRC made draft versions of PWROG-19027 NP and NEI 17-07 available for public comment as part of Draft Regulatory Guide (DG)-1362 (RG 1.200, Revision 3), and these documents were modified to address comments from stakeholders, including the Advisory Committee on Reactor Safeguards, during the RG 1.200 update process. In my professional opinion, I believe that this approach is consistent with the independence element of the POGR.

With respect to openness, the POGR state the following:

Nuclear regulation is the publics business, and it must be transacted publicly and candidly. The public must be informed about and have the opportunity to participate in the regulatory processes as required by law. Open channels of communication must be maintained with Congress, other government agencies, licensees, and the public, as well as with the international nuclear community.

As part of the RG 1.200 update process, the NRC provided members of the public opportunities to review and comment on PWROG-19027-NP and NEI 17-07. The NRC staff reviewed and addressed all public comments. In addition, the staffs proposal would require industry to submit NDM peer review implementation reports, and these reports would be available to the public in ADAMS. Therefore, in my professional opinion, I believe that the NRCs principle of openness will be met.

The principle of efficiency states, in part, the following:

Regulatory activities should be consistent with the degree of risk reduction they achieve. Where several effective alternatives are available, the option which minimizes the use of resources should be adopted.

Based on past experiences, each LAR associated with an NDM may require a significant level of staff effort. In the current regulatory framework, the staff may need to review multiple LARs associated with the same NDM, leading to a significant duplication of effort. The proposed TSs in the enclosure leverages the industrys efforts associated with the peer reviews of the NDMs and obviates the need to use significant NRC staff resources to conduct these reviews. In my professional opinion, (1) since peer reviewers will apply NRC staff-endorsed review

M. Franovich requirements in accordance with an endorsed peer review process (assuming public comments received on the DG do not reveal information or facts that cause the NRC to refrain from endorsing these documents), this efficiency is gained without affecting public health and safety and (2) use of additional resources to maintain oversight (likely diverted from the inspection of less risk-significant issues) continues to provide regulatory authority in the area of NDMs.

VII.

RECOMMENDATION In my professional opinion, the proposed TSs in the enclosure provides for an efficient means to allow licenses to use an NDM without prior NRC approval. The proposed TS also addresses when prior NRC approval of an NDM is required. Therefore, I am recommending that NRR consider incorporating the proposed TS into the NRCs Standard TSs by following the process in LIC-600, evaluating future proposals via TSTF travelers, or evaluating license amendment requests that implement the guidance in Revision 3 of RG 1.200.

M. Franovich

SUBJECT:

STAFF RESPONSE TO NUCLEAR ENERGY INSTITUTES PROPOSED TECHNICAL SPECIFICATION CHANGES ASSOCIATED WITH THE USE OF NEWLY DEVELOPED METHODS IN RISK INFORMED COMPLETION TIMES DATED: 2/02/2022

Enclosure:

Risk-Informed Completion Time Program DISTRIBUTION:

PUBLIC ADAMS Accession No.: ML19226A207 a NCP-2020-011, ADAMS Accession No. ML21112A356 NRR-106 OFFICE NRR/DRA NRR/DRA/APOB NRR/DRA/APLA NRR/DSS/STSB NAME SWeerakkody AZoulis RPascarelli VCusumano DATE 2/02/2022 1/19/2022 1/21/2022 1/12/2022 OFFICE NRR/DRO NRR/DORL NRR/DORL NAME RFelts MMarkley(NC)a BPham DATE 1/19/2022 11/30/2020 2/01/2022 OFFICIAL AGENCY RECORD

Enclosure Proposed TS [5.5.xx/5.5.yy] RISK-INFORMED COMPLETION TIME PROGRAM e.

A risk-informed completion time (RICT) must be calculated using the following techniques [list specific probabilistic risk assessment (PRA) and non-PRA techniques such as FIVE, Seismic Margins] used in the license amendment request. Changes to these PRA and non-PRA techniques require prior U.S. Nuclear Regulatory Commission (NRC) approval.

f.

PRA models used to calculate a RICT shall be maintained and upgraded to reflect the as-built, as-operated, and as-maintained plan in accordance with processes described in Regulatory Positions C.1, C.2, C.3, and C.4 in Regulatory Guide (RG) 1.200, Revision 3, Acceptability of Probabilistic Assessment Results for Risk-Informed Activities, issued December 2020.

g.

Before use by the licensee, NDMs, as defined in RG 1.200, Revision 3, must be subjected to a peer review process. The NDMs used in the licensees PRA model must meet all applicable review requirements in Tables 1-7.2-2 through 1-7.2-7 of Pressurized-Water Reactor Owners Group (PWROG)-19027-NP, Revision 2, Newly Developed Method Requirements and Peer Review, issued July 2020. The licensee must use the peer review process in Nuclear Energy Institute (NEI) 17-07, Revision 2, Performance of PRA Peer Reviews Using the ASME/ANS PRA Standard, issued August 2019. All peer review findings on NDM must be closed using an NRC-endorsed process prior to use in calculating a RICT. If any applicable requirements in Tables 1-7.2-2 through 1-7.2-7 f of PWROG-19027-NP, Revision 2, are not met, use of the NDM requires prior NRC approval. The peer review report described in Section 9.1 of NEI 17-07, Revision 2, for both the acceptability and implementation of the NDM must be retained.

Proposed TS 5.6 x. RICT Program Newly Developed Method PRA Upgrade Reporting Requirement A summary report describing the NDM and its implementation shall be submitted to the NRC following a PRA upgrade.

The summary report must be submitted following a PRA upgrade associated with an NDM before using that method in the RICT program or within 60 days after the licensee completes disposition of all peer review comments, whichever date occurs sooner. The summary report shall describe the scope of the upgrade and shall include the following:

a.

the PRA models upgraded, and the NDM used b.

a description of the acceptability of the NDM consistent with Section 5.2 of PWROG-19027-NP, Revision 2 c.

all open findings and how those findings from the NDM implementation were closed or were demonstrated not to have a significant impact on the PRA d.

all changes to key assumptions related to the NDM or its implementation