Summary of the 2nd Technical Advisory Committee (TAC) Meeting
Date:
Place:

January 19-23, 2015
Central Research Institute of Electric Power Industry (CRIEPI)Participants:
TAC:
Mr. Stetkar (Chair), Mr. Afzali, Dr. Chokshi, Mr. Pouget-Abadie, Prof.
Takada, Prof. Yamaguchi
NRRC:
Dr. Apostolakis (Head), Experts of Nuclear Risk Research Center for
respective topics
Industry:
Representatives of Federation of Electric Power Companies (FEPC),
Experts of Shikoku EPCO and Mitsubishi Heavy Industries (MHI) for
respective topics
Proceedings:
Jan. 19 (Mon)
Topic 1: Ikata Unit 3 PRA Project Plan
• PRA Promotion Task Team, which is organized by FEPC, presented its principaltask, organization chart, and schedule for PRA promotion.
• Shikoku EPCO presented its safety improvement activities including PRAutilization, the organization chart of Ikata Unit 3 PRA Project, and various
safety measures implemented at Ikata NPP.
(Handouts)••••

Outline of PRA Promotion Activities
Risk Informed Safety Improvement Program
Added Safety Functions of Ikata Unit 3Ikata Project Organization ChartTopic 2: Ikata Unit 3 PRA Event Trees• MHI, as a contractor of Shikoku EPCO for technical support of PRA, presented asample of the Ikata Unit 3 event trees and how to select initiating events for theUnit 3 PRA for internal events at power.
• TAC plans to send Shikoku EPCO a list of questions about detailed informationin the Ikata Unit 3 PRA event trees.
(Handouts)• Ikata Unit 3 Level 1 PRA for Internal Events at Power Event Trees
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Jan.20 (Tue)Topic 3: Ikata Unit 3 PRA Fault Trees• MHI presented a sample of the Ikata Unit 3 fault trees and explained Unit 3
design features, success criteria, and system analysis.
•TAC plans to send Shikoku EPCO a list of questions about details in the fault
trees for selected front line and support systems.

(Handouts)• Ikata Unit 3 Level 1 PRA for Internal Events at Power Fault Trees

Topic 4: Ikata Unit 2 PRA Event Trees• MHI presented a sample of the Ikata Unit 2 event trees and the differences indesign, selection of initiating events, and event tree success criteria between
Unit 2 and Unit 3.
• TAC plans to send Shikoku EPCO a list of questions about detailed informationin the Ikata Unit 2 PRA event trees.
(Handouts)• Ikata Unit 2 PRA for Internal Events at Power Events Trees

Topic 5: Ikata Site Seismic Hazard Analysis• Shikoku EPCO introduced AESJ-SC-P006:2007 as the seismic PRA standard,
and presented the results of the seismic hazard evaluation that has been
implemented and a summary of the proposed improved evaluation method.
(Handouts)•

Process of Seismic Hazard Evaluation on Ikata Unit 3

Topic 6: Ikata Site Seismic Fragility Analysis• Shikoku EPCO presented the procedure for fragility evaluations that have been
implemented and a summary of the proposed improved evaluation method, andreported the results of the plant walkdown for the Ikata seismic PRA project.
(Handouts)2•Process of Seismic Fragility Evaluation on Ikata Unit 3Jan. 21 (Wed)Topic 7: Ikata Unit 3 PRA Data Analysis• Shikoku EPCO presented the methods for evaluating data such as initiating
event frequencies and component failure rates, and the results of the evaluation.
• NRRC presented features of the Japanese generic data for component failurerates, common cause failure analysis, and unavailability analysis.
(Handouts)• Ikata Unit 3 PRA Data Analysis• R&D of PRA Parameters for Japanese NPPs
• Common Cause Failure Analysis in Japan• Unavailability and Recovery Failure Probability

Topic 8: NRRC Research Plan•••

NRRC presented its process for developing the R&D plan and R&D portfolio.
The Risk Assessment Research Team of NRRC presented its R&D plan.
The Risk Assessment Research Team of NRRC presented the current status ofresearch on the issue of recriticality in severe accidents as a specific technical
topic.

(Handouts)• Developing Process of R&D by NRRC
• NRRC R&D Portfolio• R&D Plan Related to Risk Assessment• Criticality Issue in Severe Accidents

Jan. 22 (Thu)
Topic 8: NRRC Research Plan
• The Risk Assessment Research Team of NRRC presented the specific researchplans for Fire PRA, Flooding PRA, and Human Reliability Analysis.
• The External Natural Hazard Research Team of NRRC presented its R&D plan,
then presented its specific research plans for Tsunami PRA, Seismic Motion /Fragility Assessment, Combination of External Hazards, Volcanic Activities,
Tornado, and Fault Displacement.
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(Handouts)• Fire PRA• Flooding PRA• Human Reliability Analysis• R&D Plan related to Natural External EventsJan. 23 (Fri)Topic 9: Planning Session• TAC, NRRC, and the PRA Promotion Task Team had a general discussion aboutschedules for this year and plans for the TAC meeting in May.
•The group agreed to a process for the exchange of focused technical information
during the periods between TAC meetings to facilitate TAC members' in-depth
understanding of complex technical issues.

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