ML24267A162

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Region II Hatch 50.69 Training (Public Version)
ML24267A162
Person / Time
Issue date: 08/26/2024
From: John Hughey, Scarborough T
NRC/NRR/DEX, NRC/NRR/DRA/APOB
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Download: ML24267A162 (1)
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Region II 10 CFR 50.69 and IP 37060 Training August 26, 2024, via Teams Thomas Scarbrough John Hughey

Disclaimer This training session is being recorded for future use in the NRCs knowledge management program. The recorded contents of the session, including any questions posted by audience members, will be preserved in accordance with the NRCs record management program and are subject to FOIA disclosure. Please refrain from including any sensitive information (i.e.,

SUNSI) in any questions that you may ask.

Please leave your chat box open to view all questions and answers posed during the session.

Purpose

  • This training is being presented to Region II in preparation for the upcoming Hatch IP 37060 inspection
  • This training session is being recorded and will be posted to the 50.69 resources SharePoint page: [...]
  • Other Regions and HQ staff have been invited to observe the training for information and Knowledge Management purposes

Agenda Time Description Presenter 9:30am - 10:30am 10 CFR 50.69 Rule - Part I Thomas Scarbrough 10:30am - 10:40am BREAK 10:40am - 11:40am 10 CFR 50.69 Rule - Part II Thomas Scarbrough 11:40am - 1:00pm Lunch and Other Business 1:00pm - 2:00pm General and Hatch-Specific Inspection Items John Hughey 2:00pm - 2:10pm BREAK 2:10pm - 3:00pm General and Hatch-Specific Inspection Items (continued)

John Hughey 3:00pm - 3:30pm Q&A All

10 CFR 50.69 Inspector Training Thomas G. Scarbrough Mechanical Engineering and Inservice Testing Branch Division of Engineering and External Hazards Office of Nuclear Reactor Regulation August 26, 2024

AGENDA 6

I.

10 CFR 50.69 Rule II.

10 CFR 50.69 License Amendment Request (LAR)

III.

10 CFR 50.69 Federal Register Notice IV.

10 CFR 50.69 Inspection Guidance V.

10 CFR 50.69 Inspections VI.

Specific 10 CFR 50.69 Technical Topics VII. Conclusion

I. 10 CFR 50.69 Rule 7

10 CFR 50.69 Overview

  • 10 CFR 50.69 allows a licensee or applicant to submit a license amendment request (LAR) to implement risk-informed treatment of structures, systems, and components (SSCs) as an alternative to special treatment requirements (STRs) in NRC regulations.
  • SRM dated October 7, 2004, approved issuance of 10 CFR 50.69 with revision of RISC-3 treatment requirements.
  • 10 CFR 50.69 issued on November 22, 2004, in 69 Federal Register Notice (FRN) 68008 8

Risk-Informed Safety Class Definitions

  • RISC-1 SSCs: safety-related SSCs that perform safety significant functions.
  • RISC-2 SSCs: nonsafety-related SSCs that perform safety significant functions.
  • RISC-3 SSCs: safety-related SSCs that perform low safety significant functions.
  • RISC-4 SSCs: nonsafety-related SSCs that perform low safety significant functions.
  • Safety significant function: function whose degradation or loss could result in a significant adverse effect on defense-in-depth, safety margin, or risk.

9

10 CFR 50.69(b), Applicability and Scope of Risk-Informed Treatment of SSCs and Submittal/Approval Process (1) LWR OL holder, Renewed LWR license holder, CP or OL applicant, and 10 CFR Part 52 design approval, COL, and manufacturing license applicant, may voluntarily comply.

(2) Submit LAR under 10 CFR 50.90 containing (i) categorization process description, (ii) systematic process description for plant evaluation, (iii) results of PRA review process, and (iv) evaluations of common cause effects and degradation mechanisms for active and passive functions.

(3) Commission will approve if 10 CFR 50.69(c) met.

(4) Include 50.69(b)(2) information in application.

10

RISC-3 and 4 STRs Eliminated by 10 CFR 50.69

  • 10 CFR 50.49 for environmental qualification of electric equipment

RISC-3 and 4 STRs Eliminated by 10 CFR 50.69 (continued)

  • 10 CFR 50.65, except for paragraph (a)(4), regarding maintenance rule
  • Type B and Type C leakage testing requirements in both Options A and B of Appendix J to 10 CFR Part 50, for penetrations and valves with specific criteria.

Examples of Regulations Not Eliminated by 10 CFR 50.69 13

  • ASME BPV Code Section III requirements in 10 CFR 50.55a, but repair/replacement activities might impact requirements.

10 CFR 50.69(c), SSC Categorization Process (1) SSCs must be categorized using a process that determines if an SSC performs one or more safety significant functions and identifies those functions and must (i) consider plant-specific PRA, (ii) determine SSC functional importance, (iii) maintain defense in depth, (iv) provide reasonable confidence for RISC-3 SSCs, and (v) be performed for entire systems and structures, not for selected components within a system or structure.

(2) SSCs must be categorized by Integrated Decision-Making Panel (IDP).

14

10 CFR 50.69(d)(1)

RISC-1 and 2 SSC Treatment Requirements The licensee or applicant shall ensure that RISC-1 and RISC-2 SSCs perform their functions consistent with the categorization process assumptions by evaluating treatment being applied to these SSCs to ensure that it supports the key assumptions in the categorization process that relate to their assumed performance.

15

10 CFR 50.69(d)(2)

RISC-3 SSC Treatment Requirements The licensee or applicant shall ensure, with reasonable confidence, that RISC-3 SSCs remain capable of performing their safety-related functions under design-basis conditions, including seismic conditions and environmental conditions and effects throughout their service life. The treatment of RISC-3 SSCs must be consistent with the categorization process. Inspection and testing, and corrective action shall be provided for RISC-3 SSCs.

16

10 CFR 50.69(d)(2)(i) and (ii)

(i) Inspection and testing. Periodic inspection and testing activities must be conducted to determine that RISC-3 SSCs will remain capable of performing their safety-related functions under design-basis conditions; and (ii) Corrective action. Conditions that would prevent a RISC-3 SSC from performing its safety-related functions under design-basis conditions must be corrected in a timely manner. For significant conditions adverse to quality, measures must be taken to provide reasonable confidence that the cause of condition is determined and corrective action taken to preclude repetition.

17

10 CFR 50.69(e), Feedback and Process Adjustment (1) RISC-1, 2, 3 and 4 SSCs. Review plant changes, operational experience, and update categorization and treatment every 2 RFOs.

(2) RISC-1 and 2 SSCs. Monitor performance and make adjustments as necessary.

(3) RISC-3 SSCs. Consider data collected in 50.69(2)(i) to determine any adverse performance and make adjustments as necessary.

18

10 CFR 50.69(f), Program Documentation, Change Control and Records (1) Document the basis for SSC categorization.

(2) Update FSAR to reflect systems categorized.

(3) When first implementing, FSAR changes do not need 10 CFR 50.59 evaluation. Thereafter, FSAR changes may be made if 10 CFR 50.69 and 50.59 continue to be met.

(4) When first implementing, QA Plan changes do not need 10 CFR 50.54(a) evaluation. Thereafter, QA Plan changes may be made if 10 CFR 50.69 and 50.54(a) continue to be met.

19

10 CFR 50.69(g), Reporting Submit LER under 10 CFR 50.73(b) for any event or condition that prevented, or would have prevented, a RISC-1 or RISC-2 SSC from performing a safety significant function.

20

II. 10 CFR 50.69 License Amendment Request 21

10 CFR 50.69 LAR Review

  • NRC staff review of an LAR to implement 10 CFR 50.69 focuses on the risk categorization process.
  • During the LAR review, NRC staff do not review treatment planned by the licensee or applicant to satisfy 10 CFR 50.69(d).
  • Licensees should discuss Technical Specifications in 50.69 LAR.
  • NRC staff has approved 50.69 implementation for many nuclear power plants.

22

III. 10 CFR 50.69 Federal Register Notice 23

10 CFR 50.69 Commission Guidance

  • 69 FRN 68008, dated Nov. 22, 2004, discusses the Commission positions on 10 CFR 50.69 and its implementation.
  • NRC inspectors should review FRN for Commission guidance.
  • FRN states that STRs are prescriptive requirements as to how licensees are to treat SSCs.
  • The following slides include highlights of the Commission guidance on specific aspects of 10 CFR 50.69.

24

FRN: Special Treatment Requirements

  • Prescriptive requirements as to how licensees are to treat SSCs (e.g., safety-related) are referred to as STRs.
  • STRs developed to provide greater assurance that SSCs will perform their functions under particular conditions with high quality and reliability.
  • STRs include particular examination techniques, testing strategies, documentation requirements, personnel qualification requirements, and independent oversight.
  • Distinction between treatment and special treatment is degree of NRC specification as to what must be implemented for particular SSCs or conditions.

25

FRN: RISC-1 and 2 Treatment

  • For RISC-1 and 2 SSCs, 10 CFR 50.69 maintains current regulatory requirements as adequate for design-basis performance.
  • 50.69(d)(1) requires sufficient treatment be applied to support credit taken for SSCs for beyond design basis events.
  • In some cases, licensees might need to enhance RISC-1 and 2 SSC treatment to support credit in categorization process to reflect actual treatment practices or document performance capability.
  • 10 CFR 50.69(e) requires monitoring and adjustment as needed based on experience.

26

FRN: RISC-3 Treatment

  • 10 CFR 50.69(d)(2) imposes requirements that are intended to maintain RISC-3 SSC design-basis capability.
  • Although individually RISC-3 SSCs are not significant to plant safety, they perform functions necessary for certain design-basis events.
  • Collectively, RISC-3 SSCs can be safety significant, and it is important to maintain their design-basis functional capability.
  • Maintenance of RISC-3 design-basis functionality is important to ensure defense-in-depth and safety margins are maintained.
  • Commission is allowing greater flexibility and lower level of assurance for RISC-3 SSCs.

27

FRN: RISC-3 Treatment (continued)

  • Licensees need to obtain data or information sufficient to make technical judgement that RISC-3 SSCs remain capable of performing safety-related functions under design-basis conditions, and to enable licensees to take actions to restore equipment performance consistent with corrective action requirements.
  • 10 CFR 50.69 rulemaking is only risk-informing the scope of STRs.
  • Process and requirements established in 50.69 do not extend to making changes to design-basis functional requirements of SSCs.

28

FRN: 50.69(d)(2) RISC-3 Treatment Guidance

  • Although 50.49 environmental qualification requirements are removed, 10 CFR Part 50, Appendix A, requirement that electric equipment important to safety be capable of performing intended functions under environmental conditions is not eliminated.
  • RISC-3 SSCs continue to be required to function under design-basis seismic conditions, but not required to be qualified by testing or specific engineering methods in accordance with 10 CFR Part 100.
  • Rule allows licensee to select technically defensible method to show RISC-3 SSCs will remain functional when subject to design earthquake loads.

29

FRN: 50.69(d)(2) RISC-3 Treatment Guidance (continued)

  • Licensee must take into account assumptions in the categorization process regarding design-basis capability and reliability of RISC-3 SSCs to perform safety-related functions throughout service life.
  • Licensee responsible for addressing vendor recommendations and operational experience.

FRN: 50.69(d)(2)(i) Inspection-Testing Guidance

  • Licensee must implement periodic testing or inspection sufficient to provide reasonable confidence that pumps and valves will be capable of performing safety-related functions under design-basis conditions.
  • Licensee will need to obtain sufficient operational information or performance data to provide reasonable confidence that RISC-3 pumps and valves will be capable of performing safety-related functions if called upon to function under operational or design-basis conditions over the interval between periodic testing or inspections.
  • Exercising a valve or pump does not provide reasonable confidence of design-basis capability.

31

FRN: 50.69(d)(2)(ii) Correction Action Guidance

  • Conditions that would prevent a RISC-3 SSC from performing safety-related functions under design-basis conditions must be corrected in timely manner.
  • In case of significant conditions adverse to quality, the rule requires measures be taken to provide reasonable confidence that the cause of the condition is determined and corrective action taken to preclude repetition.
  • Effective implementation of corrective action process would include timely response to information from plant SSCs, overall plant operations, and industry generic activities that might reveal performance concerns for RISC-3 SSCs on both individual and common-cause basis.

32

FRN: 50.69(e) Feedback and Process Adjustment

  • Date NRC grants 50.69 license amendment begins updating interval.
  • If significant adverse impact, licensee must update categorization or treatment without waiting for 2 RFO schedule.
  • Information might be from SSC performance, vendor recommendations, and operational experience including NRC information notices or generic letters.
  • Might need to move RISC-3 SSCs into RISC-1.
  • Monitor all unavailabilities and functional failures.
  • Monitor credit for beyond design basis functions.
  • Consider 50.69(d)(2)(i) data and make categorization or treatment adjustments for RISC-3 SSCs.

33

FRN: 50.69(f) Program Documentation

  • Administrative requirements for keeping information current, handling planned changes to programs and processes, and records.
  • Documentation must address why component was determined to be safety significant or low safety significant.
  • Maintain clear information on minimum level of detail about requirements.
  • No evaluation under 10 CFR 50.54 and 50.59 for initial implementation, but evaluation for future changes.
  • Categorization change control process through LAR license condition.
  • Records maintained until Commission terminates facility license.

34

FRN: 50.69(g) Reporting

  • Provides new reporting requirement applicable to events or conditions that prevented, or would have prevented, a RISC-1 or 2 SSC from performing a safety significant function.
  • Possible for events and conditions to arise that impact whether RISC-1 and 2 SSCs would perform beyond design basis functions consistent with categorization process assumptions.

35

FRN: RISC-4 Treatment Guidance

  • Justified in view of low safety significance.
  • Overall, any changes beyond STRs must be made per existing design change control requirements, including 50.59, as applicable.

36

FRN: 50.69 Implementation Inspection

  • IP will incorporate inspection guidance for monitoring 50.69 implementation.
  • Sample inspections of plants implementing 50.69
  • Inspections will focus on implementation of categorization process.
  • Inspections will also evaluate treatment under 50.69 with primary attention to programmatic and common-cause issues, including those associated with known degradation mechanisms.
  • Inspections might provide operating experience information on RISC-3 SSCs for other licensees.

37

Post-FRN Guidance 38

  • RG 1.201 states STRs removed for RISC-3 SSCs and replaced with high-level requirements intended to provide sufficient regulatory treatment, such that SSCs are still expected to perform safety-related functions under design-basis conditions, albeit at a reduced level of assurance compared to current STRs.

IV. 10 CFR 50.69 Inspection Guidance 39

Inspection Procedure IP 37060 40 IP 37060 (October 2022, ML22075A287), 10 CFR 50.69 Risk-Informed Categorization and Treatment of Structures, Systems, and Components Inspection, provides guidance for inspection of licensee programs to implement 10 CFR 50.69:

- Verify licensee programs and procedures incorporate license amendment.

- Verify licensee properly implements categorization process.

- Verify that licensee properly implements alternate treatment requirements.

IP 37060 Inspection Requirements 41

  • Review of Licensees Programs and Procedures:

- Categorization process

- RISC-1 and RISC-2 SSC treatment

- RISC-3 alternate treatment

- Feedback and process adjustments

- Program documentation, change control, and records Review of Licensees 10 CFR 50.69 Program Implementation Confirm proper categorization Implementation for entire systems RISC-1 and 2 SSC credit in PRA RISC-3 alternate treatment Reporting

IP 37060 Inspection Requirements (continued) 42 Problem Identification and Resolution Verify RISC-3 SSC failures corrected and common cause reviewed Review licensee past audits and self-assessments Review corrective actions in accordance with IP 71152 Review of Licensees Feedback and Process Adjustments

- Update categorization or treatment processes in a timely manner

- Monitor RISC-1 and 2 SSC performance and feedback

- Evaluate RISC-3 SSC data and adjustments

RISC-3 Inspection Guidance 43

  • Confirm RISC-3 SSC treatment provides reasonable confidence of performing safety-related functions.
  • Select 1 to 3 RISC-3 SSCs to verify alternate treatment program.
  • Ensure inspection, testing and corrective action reasonable because collectively RISC-3 SSCs can be safety significant.
  • Ensure extent of conditions review where treatment found deficient.
  • Industrial practices might not be sufficient alone for adequate technical basis of design-basis capability.
  • General Design Criteria in Appendix A to Part 50 continue to apply.
  • Latest IP revision provides guidance for GDC-4 environmental qualification (including aging and synergistic effects).

RISC-3 SSC Examples 44

  • RISC-3 SSCs will comprise most of the safety-related SSCs at a 50.69 plant.
  • One system may include RISC-1, 2, 3 and 4 components.
  • Typical RISC-3 component examples include:

o Residual heat removal system piping, pumps, and valves o Containment spray system piping, pumps, and valves o Service water system piping, pumps, and valves

V. 10 CFR 50.69 Inspections 45

Region II Vogtle Units 1 and 2 Inspection

  • Region II inspection at Vogtle Units 1 and 2 documented in Inspection Report No. 05000424 and 425/2016008, dated August 10, 2016 (ML16223A738)
  • Conducted June 13 to 30, 2016
  • Reviewed program procedures and implementation activities for the licensee amendment under 10 CFR 50.69
  • No findings or violations.

46

Vogtle Units 1 and 2 Inspection Report Summary

  • Licensee developed 10 CFR 50.69 program implementing procedures for categorization, alternate treatment, and feedback and adjustment processes.
  • Four systems categorized: containment spray (CS), radiation monitoring (RM), essential chilled water (ECW), and component cooling water (CCW).
  • Only one alternate treatment application
  • Due to early implementation, licensees 50.69 feedback and adjustment process activities were limited.

47

Vogtle 10 CFR 50.69 Inspection Lessons Learned 48

  • []

Vogtle PI&R Inspection Lessons Learned 49

  • []

Region I Limerick Units 1 and 2 Inspection 50

  • Inspection results documented in IR 05000352 and 353/20200010, dated March 11, 2020 (ML20073H282)
  • []

Limerick 10 CFR 50.69 Inspection Lessons Learned 51

  • []

Calvert Cliffs 10 CFR 50.69 Inspection Lessons Learned 52

  • []

Peach Bottom 10 CFR 50.69 Inspection Lessons Learned 53

  • []

Braidwood 10 CFR 50.69 Inspection Lessons Learned 54

  • []

Farley 10 CFR 50.69 Inspection Lessons Learned 55

  • []

VI. Specific 10 CFR 50.69 Technical Topics 56

RISC-1 and 2 Treatment

  • RISC-1 and 2 SSCs need to perform their functions consistent with categorization process assumptions based on applied treatment to ensure that key assumptions in the categorization process are supported.
  • In some cases, licensees might need to enhance RISC-1 and 2 SSC treatment to support credit taken in categorization process to reflect actual treatment practices and/or document performance capability.
  • 50.69(e) requires monitoring and adjustment as needed based on experience in implementing 10 CFR 50.69.

57

RISC-3 MOV Treatment

  • Licensee must satisfy 10 CFR 50.69(d)(2) for RISC-3 MOVs, including inspection and testing, and corrective action.
  • In 69 FR 68008, Commission provides guidance for inspection and testing, and corrective action, for RISC-3 MOVs to demonstrate reasonable confidence in their capability to perform safety functions.

58

RISC-3 Piping Replacement

  • Commission specifies RISC-3 SSCs required to be capable of withstanding design input earthquake loads and required load combinations for RISC-3 SSC design, but seismic qualification under 10 CFR Part 100 is not required.
  • Commission states licensee must have technically defensible method for demonstrating replacement piping can withstand design seismic loads.
  • Regarding ASTM versus ASME piping, adequate pedigree needs to be demonstrated (such as B31.1 piping).
  • Fracture toughness requirements need to be satisfied if included in original design specification.

59

ANO Passive Component Classification Method

  • In SE dated 4-22-2009, NRC authorized use of risk-informed safety classification and treatment program for repair/replacement activities in Class 2 and 3 systems at ANO-2 (ML090930246).
  • LSS components are exempt from ASME BPV Code for repair/replacement activities, but owner-defined activities confirm with reasonable confidence that LSS item will perform safety functions under design-basis conditions.
  • Treatment will include design controls, procurement, installation, inspection, and configuration control.
  • Entergy stated that original construction code fracture toughness requirements will be met.

60

Systems in Categorization Process

  • 10 CFR 50.69(c)(v) states the categorization process must: Be performed for entire systems and structures, not for selected components within a system or structure.
  • FRN on 68019 states that this scope ensures that all safety functions associated with a system or structure are properly identified and evaluated, and that the entire set of components that comprise a system or structure are considered and addressed.
  • All functions for a given component need to be appropriately considered, if not the component should remain uncategorized
  • Bases for system boundaries may be equipment tag designators or other means as documented by the licensee.

61

Pipe Support Classification for 10 CFR 50.69 Plants

  • []

62

Operational Leakage for 10 CFR 50.69 Plants

  • For RISC-3 and 4 SSCs that are ASME BPV Code Class 2 or 3, ISI and repair/replacement requirements (except fracture toughness) in 50.55a do not apply when implementing 10 CFR 50.69.

10 CFR 50.69 Welder and Inspector Capability

  • RISC-1 and 2 SSC requirements for welder and inspector qualification remain applicable under 10 CFR 50.69.
  • For RISC-3 SSCs that are ASME BPV Code Class 2 and 3, ISI and repair and replacement requirements (except fracture toughness) in 10 CFR 50.55a do not apply.
  • FRN does not address RISC-3 SSC welder or inspector capability, but refers to a technically defensible method in discussing various aspects of RISC-3 SSC capability.

64

Reportability for 10 CFR 50.69 Plants

  • STR reporting requirements continue to apply for RISC-1 and 2 SSCs, but reporting requirements for RISC-3 and 4 SSCs are removed.
  • In addition, 10 CFR 50.69(g) requires licensees to submit a licensee event report for any event or condition that would have prevented RISC-1 or RISC-2 SSCs from performing a safety significant function.
  • FRN states it is possible for events and conditions to arise that impact whether RISC-1 or RISC-2 SSCs would perform beyond design basis functions consistent with the performance capability credited in the categorization process. This reporting requirement is intended to capture these situations.

65

Technical Specifications versus 10 CFR 50.69

  • 10 CFR 50.55a requirements for Inservice Testing of RISC-3 and 4 components are removed by 10 CFR 50.69 with separate requirements for testing and inspection of RISC-3 components.
  • Some TS refer to Inservice Testing Program for Surveillance Requirements (SRs) for component testing.
  • []

66

VII. Conclusion

  • 10 CFR 50.69 allows flexibility for licensees in applying treatment to plant SSCs based on their safety significance determined by the 50.69 categorization process.
  • 10 CFR 50.69 requires that SSCs with low safety significance be capable of performing their safety functions but with less confidence than when applying STRs.

67

Contacts Tom Scarbrough Thomas.Scarbrough@nrc.gov John Hughey John.Hughey@nrc.gov Aron Lewin Aron.Lewin@nrc.gov 68

Farley IP37060 Inspection 10 CFR 50.69 Implementation (Inspection Insights/Items From Amendment SE)

John Hughey Office of Nuclear Reactor Regulation Division of Risk Assessment PRA Oversight Branch

TOPICS 70 General Inspection Items Hatch-Specific Items

GENERAL INSPECTION ITEMS 71 Documentation Integrated Review Team packages screenings/evaluations supporting categorization risk characterization SSC assessment worksheets risk sensitivity studies

  • address key sources of uncertainty in the PRA (risk sensitivity studies - section 5)
  • performed to ensure that assumptions in the PRA are not masking the importance of SSC alternative treatment evaluations (integrated risk sensitivity study - section 8) defense-in-depth characterization

GENERAL INSPECTION ITEMS 72 Documentation Fleet and plant program procedures including:

performance monitoring procedures

  • consistent with the sensitivity studies
  • intersystem CCFs monitored/identify mechanisms
  • identify/implement process adjustments IDP Procedures
  • qualifications/training/makeup

GENERAL INSPECTION ITEMS 73 Documentation Any CRs related to 50.69 program corrective actions resulting in PRA review of procedures, modifications, etc. consistent with the sensitivity studies causal analysis impacting 50.69 program or PRA configuration/control

GENERAL INSPECTION ITEMS 74 Documentation Printout of PRA change tracking database related to 50.69 program since amendment issued (June 2020)

UFSAR changes supporting SSC categorization

GENERAL INSPECTION ITEMS 75 Documentation ANO 2 passive categorization process component with only a pressure-retaining function passive functions of active components (MOV body)

RI safety classification/treatment for repair/replacement activities for Class 2 and Class 3 components and supports only no Class 1

GENERAL INSPECTION ITEMS 76 Integrated Decision-making Panel (IDP) Composition 50.69(c)(2) Requires Members With Expertise In:

PRA/safety analysis/plant operations/design engineering/system engineering No set number of members LAR adds:

3 members with a min. 5 years plant experience 1 member with min. 3 years experience modeling

/updating PRA IDP training

GENERAL INSPECTION ITEMS 77 Alternative Treatments 50.69(b) - not a de facto exemption allows alternative treatment (reasonable confidence NUREG/CR-6752) must continue to comply with special treatment reg.

unless alternative treatment established 50.69(d)(2) - two performance-based requirements:

inspection/testing corrective action

GENERAL INSPECTION ITEMS 78 Periodic Review/Update 50.69(e)(1) - timely not to exceed 2 refueling outages 2 refueling outages since implementation?

(LAR issued in 6-2020) 50.69(e)(3) - specific RISC-3 updates Look for CRs identifying RISC-3 performance issues From NEI 00-04:

Performance monitoring of RISC-3 SSCs, as required by 10 CFR 50.69(e)(3),

is established to provide assurance that potential increases in failure rates will be detected and addressed before reaching the rate assumed in the integrated sensitivity study.

GENERAL INSPECTION ITEMS 79 IMPLEMENTATION of NEI 00-04 GUIDANCE NEI 00-04 generally describes the process in a linear manner.

However, the process can be implemented in an integrated and parallel manner - this is typically how licensees implement.

The following slides will describe the process:

First, we will discuss the in-series/linear approach for clarity.

Next, we will discuss the integrated/parallel approach.

GENERAL INSPECTION ITEMS IDP Allowed Consideration for HSS to LSS 80 HSS to LSS consideration not allowed if HSS due to:

IEPRA integrated PRA importance measures Shutdown DID passive categorization LAR Table 3-1 approved in NRC SE Section 3.2.4.6 as consistent with NEI 00-04.

HSS to LSS consideration allowed if HSS due to:

SPRA FPRA sensitivity studies outlined in Section 5

  • Note: Hatch has SPRA and FPRA

GENERAL INSPECTION ITEMS 81 Periodic Review/Update 50.69(e)(1) - timely not to exceed 2 refueling outages 2 refueling outages since implementation in 10-2018?

50.69(e)(3) - specific RISC-3 updates Look for CRs identifying RISC-3 performance issues From NEI 00-04:

Performance monitoring of RISC-3 SSCs, as required by 10 CFR 50.69(e)(3),

is established to provide assurance that potential increases in failure rates will be detected and addressed before reaching the rate assumed in the integrated sensitivity study.

GENERAL INSPECTION ITEMS 82 Periodic Review/Update 50.69(e)(1) - timely not to exceed 2 refueling outages 2 refueling outages since implementation in 10-2018?

50.69(e)(3) - specific RISC-3 updates Look for CRs identifying RISC-3 performance issues From NEI 00-04:

Performance monitoring of RISC-3 SSCs, as required by 10 CFR 50.69(e)(3),

is established to provide assurance that potential increases in failure rates will be detected and addressed before reaching the rate assumed in the integrated sensitivity study.

GENERAL INSPECTION ITEMS NEI 00-04 Fig. 1-2: Summary of NEI 00-04 Categorization Process 83 Section 5 Section 6 Section 8 Section 9

GENERAL INSPECTION ITEMS NEI 00-04 Fig. 1-2: Summary of NEI 00-04 Categorization Process 84 Section 5 Section 6 Section 8 Section 9 Whats missing?

GENERAL INSPECTION ITEMS NEI 00-04 Fig. 1-2: Summary of NEI 00-04 Categorization Process 85 Section 5 Section 6 Section 8 Section 9 Section 7 - Coarse Categorization:

If any SSC is safety significant, from either the PRA-based component safety significance assessment (Section 5) or the defense-in-depth assessment (Section 6), then the associated system function is preliminarily safety significant. All other functions/SSCs can be preliminarily assigned low safety significance.

Once a system function has been identified as safety-significant, then all components that support this system function are assigned a preliminary safety-significant categorization. All other components are assigned a preliminary LSS categorization.

Section 7

GENERAL INSPECTION ITEMS NEI 00-04 Fig. 1-2: Summary of NEI 00-04 Categorization Process 86 Section 5 Section 6 Section 8 Section 9 What else is missing?

Section 7

GENERAL INSPECTION ITEMS NEI 00-04 Fig. 1-2: Summary of NEI 00-04 Categorization Process 87 Section 5 Section 6 Section 8 Section 9 Section 10.2 - Detailed Categorization:

Each licensee has the option, based on the estimated benefit, of performing additional engineering and system analyses to identify specific component level or piece part functions and importance for the safety-significant SSCs.

Section 7 Section 10

GENERAL INSPECTION ITEMS NEI 00-04 Fig. 1-2: Summary of NEI 00-04 Categorization Process 88 Section 5 Section 6 Section 8 Section 9 Special Note on Section 6 - DID Characterization:

In cases where the component is safety-related and found to be of low risk significance, it is appropriate to confirm that defense-in-depth is preserved.

This means only PRA-modeled preliminary LSS SSCs initially went through the Section 6 DID assessment. Section 10.2 may consider non-modeled SSCs that were HSS simply due to the Section 7 coarse categorization or, are HSS, but can be downgraded. If the SSC meets the 10.2 LSS criteria, it must then go through the section 6 DID assessment, etc...

Section 7 Section 10

HATCH - SPECIFIC ITEMS 89 Specific Areas for Inspection Consideration License Condition License Condition implementation item FLEX credit in the PRA models

HATCH - SPECIFIC ITEMS 90 License Condition Southern Nuclear Operating Company is approved to implement 10 CFR 50. 69 using the processes for categorization of Risk-Informed Safety Class (RISC)-1, RISC-2, RISC-3, and RISC-4 structures, systems, and components (SSCs) specified in the Renewed License Amendment No. 250 dated June 26, 2020.

HATCH - SPECIFIC ITEMS 91 License Condition Hatch License Condition requires implementation of categorization per processes specified in license amendment dated June 26, 2020.

Item 1.A of the amendment identifies the application dated June 7, 2018, and supplements.

Item 1.B states: The facility will operate in conformity with the application,

LAR application states: The categorization process being implemented through this change is consistent with Nuclear Energy Institute (NEI) 00-04

HATCH - SPECIFIC ITEMS 92 License Condition Therefore: regulatory requirement via the Hatch License Condition to implement consistent with NEI 00-04.

Key phrase is consistent with - SE repeats, consistent with.

Implementation may not be exactly like NEI 00-04, but it cannot be a different approach that conflicts with NEI 00-04.

But - consistent with can be murky and a violation requires a performance deficiency. (performance based/risk significant)

Focus - did the licensee get to the right categorization result?

HATCH - SPECIFIC ITEMS 93 License Condition Prior NRC approval, under 10 CFR 50.90, is required for a change to the categorization process specified above (e.g., change from a seismic margins approach to a seismic probabilistic risk assessment approach).

Generalized example - Hatch uses seismic PRA for categorization, not a seismic margins approach.

Hatch uses ANO passive categorization - not specified in License Condition (covered in 1st paragraph)

HATCH - SPECIFIC ITEMS 94 License Condition Implementation Item Prior to implementation of the Renewed License Amendment No. 250 dated June 26, 2020, Southern Nuclear Operating Company shall update the Probabilistic Risk Assessment (PRA) models to reflect the as-built, as-operated, and as-maintained plant and shall ensure the risk acceptance guidelines found in Regulatory Guide (RG) 1.174, Revision 3 are met.

LAR initial proposed License Condition focuses on modifications listed in Att. 1 affecting the Fire PRA to achieve an overall CDF and LERF consistent with NRC Regulatory Guide 1.174 risk limits, Final as-issued License Condition is broader than initially proposed and applies to any PRA model updates that may be required prior to implementation.

HATCH - SPECIFIC ITEMS 95 Use of FLEX in PRA Model

Per 7/16/2019 LAR Supplement response to RAI 06:

Certain FLEX equipment installed as permanent plant equipment is credited in the IEPRA, FPRA and SPRA models.

Plant procedures have been revised to include operation of this permanently installed equipment.

No FLEX actions outside of the main reactor buildings or control building are credited in the PRA models.

Credited operator actions have been peer reviewed and are similar to other operator actions evaluated using approaches consistent with the endorsed ASME/ANS PRA Standard.

May want to confirm that any FLEX-related changes since LAR approval have been evaluated have been addressed for 50.69 categorization.

96 10 CFR 50.69 INSPECTION PROCEDURES IP-37060 Implementation Inspection Inspection Helps:

Hatch 50.69 Amendment SE (ML20077J704)

Hatch 50.69 Initial LAR (ML18158A583)

Hatch 50.69 Supplement 7-16-2019 (ML19197A097)

97 10 CFR 50.69 INSPECTION PROCEDURES IP-37060 Implementation Inspection Inspection Helps:

Hatch 50.69 Supplement 12-18-2019 (ML19352F705)

Hatch 50.69 Supplement 6-2-2020 (ML20154K716)

DRA FLEX Credit Assessment Memo (ML17031A269)*

98 10 CFR 50.69 INSPECTION PROCEDURES IP-37060 Implementation Inspection Inspection Helps:

NEI 00 (ML052900163)

RG 1.201, Rev. 1 - (ML061090627)

NUREG/CR-6752 - (ML020330051) 10 CFR 50.69 Inspection Guidance and Resources ([])

CONTACTS 99 Tom Scarbrough Thomas.Scarbrough@nrc.gov John Hughey John.Hughey@nrc.gov Aron Lewin Aron.Lewin@nrc.gov

QUESTIONS

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