ML25216A237

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RIPE Workshop - Session 1 RIPE Training (1)
ML25216A237
Person / Time
Issue date: 08/04/2025
From: Michelle Kichline
Office of Nuclear Reactor Regulation
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ML25216A235 List:
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Download: ML25216A237 (1)
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Text

Michelle Kichline, NRR/DRA Senior Reliability and Risk Analyst

2 Agenda

  • Purpose and approval of RIPE
  • Requirements to use RIPE
  • Safety impact characterization process
  • RIPE criteria and relation to existing risk metrics
  • How a RIPE review differs from other reviews
  • Role of the integrated decision-making panel (IDP)
  • Roles and responsibilities of the technical reviewers
  • Purpose and scope of the no technical objection (NTO) review
  • Difference between requests for confirmation of information (RCIs) and requests for additional information (RAIs)
  • RIPE review schedule 2

3 Purpose of RIPE

  • RIPE leverages current regulations and risk-informed initiatives to allow licensees to request plant-specific exemptions or license amendments for low safety significance (LSS) issues using a streamlined NRC review process.
  • RIPE establishes a more efficient process to review LSS licensing actions that address issues within the licensing basis.
  • RIPE can be used to address LSS licensing actions using existing regulations under 10 Code of Federal Regulations (CFR) 50.12 or 50.90.
  • RIPE is consistent with our RG 1.174 risk-informed integrated decision-making principles.

4 Approval of RIPE

  • Adoption of RIPE was initially approved by the NRR Office Director by memo dated January 7, 2021 (ML21006A324) with 2 guidance documents:

- Enclosure 1 - Guidelines for Characterizing the Safety Impact of Issues (SIC)

- Enclosure 2 - Temporary Staff Guidance TSG-DORL-2021-01 (RIPE TSG)

  • RIPE was expanded to apply to more licensees with TSTF-425 amendments in Revision 1 in June 2021 (Package ML21180A011).
  • RIPE was expanded to include technical specification changes in Revision 2 in May 2022 (Package ML22088A140).
  • RIPE TSG Revision 3 was issued in September 2023 to incorporate enhancements from the first RIPE review (ML23122A014).
  • In May 2024, RIPE TSG Revision 4 (ML23354A150) and SIC Revision 3 (ML23354A152) were issued to incorporate NEI feedback to increase the risk acceptance criteria.

5 Requirements to use RIPE

  • Previously NRC-approved license amendment to adopt either:

- Risk-Informed Completion Times (TSTF-505, Initiative 4b)

- Surveillance Frequency Control Program (TSTF-425, Initiative 5b)

  • The proposed change is completely within the scope of the licensees PRA model or can be bounded using surrogates and is within the scope of the portion(s) of the PRA model that was found acceptable by the NRC.
  • All license conditions for the applicable license amendments have been completed.

6 RIPE leverages previously approved risk-informed initiatives PRA IDP RIPE (using existing regulations)

Integrated Decision-making Panel (IDP) Reviews Key Engineering Principles Previously Approved Risk-Informed Amendment Demonstrates Probabilistic Risk Assessment (PRA)

Acceptability

Licensee identifies a licensing issue that has a minimal safety impact Licensee documents the exemption or amendment request using Safety Impact Characterization Guidance for Implementing RIPE (SIC)

Licensee requests licensing action per streamlined review process 7

NRC reviews licensing action using streamlined review guidance in TSG-DORL-2021-01 Approval Process Safety Impact Characterization Submittal to NRC Implementation of RIPE NRC Actions Licensee Actions

8 Safety Impact Characterization Overview

9 Safety Impact Characterization Define the issue Explore the issue in detail using a Generic Assessment Expert Team (GAET) and/or plant-specific integrated decision-making panel (Plant IDP)

Finalize responses to the screening questions Preliminary Screening Questions Does the issue:

1. Result in any impact on the frequency of occurrence of an accident initiator or result in a new accident initiator?
2. Result in any impact on the availability, reliability, or capability of SSCs or personnel relied upon to mitigate a transient, accident, or natural hazard?
3. Result in any impact on the consequences of an accident sequence?
4. Result in any impact on the capability of a fission product barrier?
5. Result in any impact on defense-in-depth (DID) capability or safety margin (SM)?

10 Safety Impact Characterization Consider risk management actions Assess the cumulative risk Is the risk impact minimal?

Characterize the issue as having a minimal safety impact Assess performance monitoring strategies Characterize the issue as having a more than minimal safety impact All of the following must apply to characterize an issue as having a minimal safety impact:

  • CDF less than 5 x 10-7 / year.
  • LERF less than 5 x 10-8 / year.
  • The issue screens to no impact or minimal impact using the screening questions.
  • Cumulative risk is acceptable.
  • Performance monitoring is established.

11 RIPE Criteria CDF of Proposed Change

< 5 x 10-7 LERF of Proposed Change

< 5 x 10-8 PRA Technical Acceptability Approved TSTF-425 or TSTF-505 Non-Risk Impacts (Includes impact on accident initiators, reliability of SSCs, fission product barriers, dose, DID, SM)

Screens to No or Minimal Impact Cumulative Risk (CDF/LERF)

< 1 x 10-4 / 1 x 10-5 Risk Criteria Other Criteria

12 RIDM for RIPE Acceptable PRA Model IDP Issue contributes

<5E-7/yr to CDF Issue contributes

<5E-8/yr to LERF Minimal increase in the frequency of a risk-significant accident initiator Minimal decrease in availability, reliability, or capability of an SSC Minimal increase in consequences (dose)

Minimal decrease in the capability of a fission product barrier Minimal decrease in DID or SM Acceptable Cumulative Risk Performance Monitoring Strategies

13 Risk Criteria

  • RIPE has lower risk acceptance criteria for CDF and LERF than that for acceptable changes in RG 1.174.
  • PRA technical acceptability is verified through previously approved license amendments (TSTF-425 or TSTF-505).

RIPE RG 1.174 Criteria

14 How does RIPE differ from other risk-informed reviews?

No Legal Objective (NLO)

OGC OGC Requests for Information Audits, RAIs, and RCIs allowed RCIs allowed, Audits/RAIs not typical Development of the Safety Evaluation (SE)

All assigned reviewers Lead reviewer only Acceptance Review No Technical Objection (NTO) Review All assigned reviewers All assigned reviewers Other Risk-Informed Review RIPE Review

15 Is RIPE Risk-Based?

RIPE leverages the IDP to evaluate the key principles associated with the proposed change.

The IDP process has been reviewed, approved, and inspected by the NRC as part of 50.69 (Risk-Informed Categorization of SSCs).

Technical staff will review the submittal and IDP results to ensure the licensees safety impact characterization is reasonable.

DRA staff will review the submittal to ensure the RIPE criteria are met, including that defense-in-depth (DID) and safety margins (SM) are maintained commensurate with the low safety significance of the issue.

DID IDP Safety Margins

16 Roles and Responsibilities

  • Subject Matter Expert (SME) Technical Reviewers

- Participate in pre-submittal meetings.

- Review submittal and IDP results to ensure the licensees safety impact characterization is reasonable.

- Perform the NTO review for the reviewers technical area of expertise.

- Not responsible for providing SE input.

  • Lead Technical Reviewer

- Participate in pre-submittal meetings.

- Review submittal and IDP results to ensure the RIPE criteria are met.

- Perform the acceptance review.

- Develop and review any RCIs required to make a regulatory conclusion in the SE.

- Document the acceptability of the proposed change in accordance with the SE template.

17 What is the No Technical Objection (NTO) Review?

  • Providing an NTO means that the SME technical reviewer has no objection to applying RIPE for the request without additional review in the SMEs respective technical area.

- The NTO review entails reviewing the request to ensure that the concerns related to the branchs technical area have been considered by the IDP.

  • The NTO review includes reviewing whether

- the assumptions and methodology used in the submitted analysis are reasonable,

- the licensee fully considered the technical aspects of the issue under consideration to support the IDPs determination, and

- the screening questions were answered adequately by the licensees IDP.

  • The depth of the NTO review should be commensurate with the very low safety significance of the issue.

18 What if there is a technical objection?

  • Technical objections (TOs) must be approved by the reviewers branch chief and supported by a sound regulatory basis that explains how the concern challenges the safety impact characterization.
  • If the concern would not change the licensees safety impact characterization (i.e., the proposed change would still have no or a minimal safety impact), the concern does not rise to the level of a TO for RIPE.

- If the concern does not rise to the level of a TO, discuss the concern with the review team and determine whether an RCI would alleviate the concern.

  • If a TO is identified, the PM, DORL BC, Technical BC, and DRA BC will decide how to address the TO and whether the submittal should proceed under RIPE or reviewed under LIC-206.

- Audits and RAIs can be used on a case-by-case basis to resolve the TO.

19 RAIs vs RCIs

  • RAIs request new or unknown information from the licensee that is needed to make a regulatory conclusion in the SE.

- RAIs are not typically allowed as part of RIPE.

- If RAIs are needed, the submittal can still be accepted as a regular license amendment or exemption and reviewed under LIC-206.

  • RCIs are used when the staff needs known information to be provided on the docket for use in the SE.

- For example, an RCI would be appropriate if the staff wants to use information in the SE that was provided by the licensee as part of a pre-submittal meeting but was not included in the submittal.

- RCIs are allowed as part of RIPE.

20 Streamlined NRC Review Timelines T < 20 Weeks DORL Issues LAR to Licensee T < 17 Weeks OGC NLO to DORL T < 15 Weeks DORL SE to OGC T < 10 Weeks SE Input to DORL T < 8 Weeks DORL PM Submits FRN T < 5 Weeks Acceptance Review Issued

  • T=0 Licensee Submits RIPE Exemption Timeline for Exemptions

21 Resource Estimate

  • The estimate to complete a RIPE request is approximately 80 hours9.259259e-4 days <br />0.0222 hours <br />1.322751e-4 weeks <br />3.044e-5 months <br />.

- This estimate includes 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> for each NTO review.

  • For more complex submittals, the PM and DORL BC have some flexibility to revise these estimates as needed to ensure the staff has adequate time to complete their review.
  • Once resource estimates are communicated to the staff, the PM and DORL BC must approve changes.

22 Questions?

Backup Slides

24 Milestones for an Exemption Request ACCEPTANCE REVIEW MILESTONES SCHEDULE DATE 1

PM creates project in the NRR workload management tool T* = 0 2

PM reviews submittal for information sufficiency

< T = 14 days (2 weeks) 3 Technical staff determines if there is any technical objection to applying the RIPE process and provides recommendation to PM

< T = 28 days (4 weeks) 4 PM notifies licensee or applicant (e.g., via call, email or letter) that LAR meets the criteria for a streamlined review and is acceptable for review under the RIPE process

< T = 35 days (5 weeks) 5 PM records the date of acceptance review notification in the NRR workload management tool

< T = 35 days (5 weeks)

TECHNICAL REVIEW AND PROCESSING MILESTONES SCHEDULE*

DATE 1

DRA SE input provided to PM

< 49 days (7 weeks) 2 PM provides exemption package to OGC for NLO review

< 63 days (9 weeks) 3 OGC provides NLO response to PM

< 77 days (11 weeks) 4 NRC completes its review of the LAR

< 91 days (13 weeks)

25 Milestones for a LAR ACCEPTANCE REVIEW MILESTONES SCHEDULE DATE 1

PM creates project in the NRR workload management tool T* = 0 2

PM reviews submittal for information sufficiency

< T = 14 days (2 weeks) 3 Technical staff determines if there is any technical objection to applying the RIPE process and provides recommendation to PM

< T = 28 days (4 weeks) 4 PM notifies licensee or applicant (e.g., via call, email or letter) that LAR meets the criteria for a streamlined review and is acceptable for review under the RIPE process

< T = 35 days (5 weeks) 5 PM records the date of acceptance review notification in the NRR workload management tool

< T = 35 days (5 weeks)

TECHNICAL REVIEW AND PROCESSING MILESTONES SCHEDULE*

DATE 1

PM issues the notice of application in Federal Register

< 64 days (8 weeks) 2 DRA SE input provided to PM

< 70 days (10 weeks) 3 PM provides amendment package to OGC for NLO review

< 105 days (15 weeks) 4 OGC provides NLO response to PM

< 119 days (17 weeks) 5 NRC completes its review of the LAR

< 140 days (20 weeks)

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