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Summary of Draft NEI Guidance - November 6, 2013- GUIDELINES FOR PRIORITIZATION AND SCHEDULING IMPLEMENTATION Pre-Draft 1 – September 30, 2013 1.

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Presentation on theme: "Summary of Draft NEI Guidance - November 6, 2013- GUIDELINES FOR PRIORITIZATION AND SCHEDULING IMPLEMENTATION Pre-Draft 1 – September 30, 2013 1."— Presentation transcript:

1 Summary of Draft NEI Guidance - November 6, GUIDELINES FOR PRIORITIZATION AND SCHEDULING IMPLEMENTATION Pre-Draft 1 – September 30,

2 Cumulative Impact Management DRAFT

3 Purpose Summarize guidance contents Summarize work remaining Provide overview of process Provide basis of safety ranking Discuss basis for confidence in approach Next Steps 3

4 Guidance Table of Contents 1 Introduction 1.1 Purpose 1.2 Content of this Guidance Document 2 Definitions and Applicability of Terms 3 Process Considerations 3.1 Key Characteristics of the Process 3.2 Basic Approach to Prioritization 3.3 Philosophy 3.4 Guidelines from SDP 4 Implementation Guidance 4.1 Safety 4.2 Security (In draft) 4.3 Plant Personnel Safety (Partially developed; ALARA) 4.4 External Impacts (Not developed) 4.5 Aggregating Rankings (Not developed; comparable to SAMA) 4.6 Benefit-Cost Assessment (Generic characterization and plant-specific benefit-cost) 4.7 Generic Assessment Evaluation Team (Separate guidance in draft) 4.8 Integrated Decision Making Panel (Separate guidance in draft) 5 Integrated Implementation Scheduling (Build on typical processes used today) 6 Reassessment, Review and Reconciliation (Not developed; use typical processes) 7 Documentation (Not developed; use typical processes) 8 References 4

5 Appendices Appendix A Background - History and Relevant Reference Documents Appendix B Guidance for Step 1 (Screening for Beneficial or Adverse Effects) Appendix C Guidance for Step 2 (More Than Minimal) Appendix D Basis for Matrix Appendix E Guidance for Step 3A(Qualitative Assessment of VL, L, M, H) 5

6 Overview of Prioritization Approach Safety impact is the primary focus SDP thresholds are used (reverse perspective) Regulatory issues and plant-initiated activities are prioritized into broad categories spanning a decade Questions to focus assessment are based on risk informed adaptation of NEI’s (10CFR50.59) guidance and SDP Definition of “more than minimal” is consistent with RG guidelines for small increase in risk and 10% change in initiator frequency per guidance Cost/benefit is a consideration consistent with Severe Accident Mitigation Alternatives (SAMA) approach 6

7 Key Elements and Features of Prioritization Generic characterization of regulatory issues by expert team –Problem statement and potential solutions –Considerations for plant-specific prioritization –Assignment of generic priority to be determined Plant-specific evaluation Formal plant review by Integrated Decision-making Panel like 50.65, 50.69, RITS 5b Inputs to integrated scheduling 7

8 Safety Ranking Current Relative Risk Level minus Projected Relative Risk Level Relative Improvement Approach used for Matrix Matrix includes Lower Bound, Midpoint and Upper Bound to display Impact of Factor of 10 range (to address uncertainty considerations) Tabletops to Refine 8

9 P-S Prioritization Process Guidance 9

10 Matrix by Current Risk and Potential Impact UB is upper bound of the risk range; Mid is “mid-range” (0.3 times UB); LB is factor of 10 lower than UB Current Risk associated with Issue Note: Address the specific issue first; then assess impacts on other risk contributors potentially impacted Potential Impact of Action (Reduction in Risk) NoneVery Small/MinimalSmallMediumHighComments 0%0-25%25-50%50% to 90%>90%Can adjust these initial ranges as appropriate Outcome Note: Quantitative values are delta CDF/LERF Green (VL) LB

11 Progressive Screening Step 1: No Impact or Adverse Impact? Step 2: Minimal Impact? Step 3A: Relative Impact versus Current Relative Risk -Very Low -Low -Medium -High Step 3B: Quantitative 11

12 Safety Evaluation Questions (No, Adverse, Less than Minimal, Relative Impact) 1. Frequency of occurrence of an accident initiator? 2. Availability, reliability, or capability of SSCs and personnel relied upon to mitigate a transient, accident, or natural hazard? 3. Consequences of an accident sequence? 4. Capability of a fission product barrier? 5. Improvement in defense-in-depth capability? Examples include: a. Strengthen balance of accident prevention and mitigation b. Reduce reliance on programmatic activities c. Reduce probabilities of common-cause failures Note: Risk significance is also addressed in Steps 2 (minimal) and 3 (relative change) 12

13 Minimal Impact To be more than minimal the effect of a proposed activity must be discernible and attributable to the proposed activity An impact of delta CDF and LERF of less than 1E- 6/1E-7 per year respectively (SDP) Accident initiators contributing less than 1% of total CDF/LERF (consistent with RG 1.174) Less than 10% change in frequency (as this is insignificant and consistent with guidance) 13

14 Initiator Considerations Initiator Categories (Representative) Risk Significant? No, Adverse, Less than Minimal, L, M H Impact? Transients initiated by frontline systems Transients initiated by support systems Primary system integrity loss (e.g. SGTR, RCP seal LOCA, LOCA) Secondary system integrity loss Internal flooding Internal fires Earthquakes External flooding Tornados and High Winds Other External Hazards 14

15 Considerations for each Initiator Potentially Affected Considerations Potential Action Effect? No, Adverse, Less than Minimal, L, M, H Impact? Changes in maintenance, training Changes in specific SSCs (e.g., installing a more reliable component) Changes in materials Equipment replacements to address age related degradation Changes in redundancy and diversity Addition of equipment Changes in operating practices 15

16 SSCs Considerations Considerations Potential Action Effect? None, Adverse, Less than Minimal, L, M, H Impact? Changes in maintenance, testing, training Changes in specific SSCs (e.g., installing a more reliable component) Changes in materials Equipment replacements to address age related degradation Changes in redundancy and diversity Addition of equipment Strengthening of equipment Moving equipment (to reduce the impacts of spatial events) Eliminating the need for recovery action (RA) Improving performance shaping factor related to human performance Changes in operating practices 16

17 Types of Models and Evaluation Tools - Large Tool Box The appropriate model/tool will depend on the issue Qualitative checklist Comparison to a previously ranked issue (s) –which is addressed by using a pairwise comparison Review of Previous Studies (e.g. SAMA and Issue- specific cost-benefit evaluations) Direct use of an existing PRA model Adaptation of an existing PRA model Development of a new PRA model (e.g. a focused scope assessment) Direct, adaptive or new deterministic model, such as to characterize margin in system capability 17

18 Generic Assessment Expert Team (GAET) An expert team to assess issues and develop the generic characterization of potential actions Comprised of Industry leaders supported by subject matter experts (SMEs), as needed GAET uses available NRC and Industry information GAET uses the process in the framework of a Generic Integrated Decision Making Panel (GIDP) Draft Guidance has been developed Based on Integrated decision-making Panel approaches used for Maintenance Rule RI ISI 18

19 Generic Assessment Expert Team (GAET) Output of the GAET deliberations is -A document of issue and significance characterization, cost-benefit, and associated bases -Includes identification of plant-specific (P-S) considerations which could influence the significance on a P-S basis Actual structure, format, team makeup, etc. is to be determined 19

20 Plant-Specific Integrated Decision Making Panel (P-S IDP) P-S IDP is used to support final rankings on a plant-specific basis IDP would not establish prioritization -Instead they should conduct a “peer” check For example, in addition to reviewing the rankings developed by plant subject matter experts (SMEs) and the outcome of the GAET -The P-S IDP could conduct a pairwise comparison If the P-S IDP conducts the actual rankings, the benefits of a peer check would not be achieved 20

21 Summary Approach is based on proven risk-informed approaches -SDP -In-service Inspection -Use of an IDP SDPs and SAMAs are routinely completed successfully -Do not require significant effort -We can repeat these successes on Cumulative Effects Comments, questions and piloting Refine Guidance 21

22 Next Steps Perform Tabletops (weeks of Dec. 9 and 16) Potential Issues for Tabletops -NFPA-805 -Security (physical and cyber) -A Fukushima issue (e.g., SFP Instrumentation) -GSI-191 -RCP Seal -Station Blackout -Emergency Preparedness 22


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