Ageing Management and Safe Long Term Operation of Japanese Light Water Reactors

Transcription

1 IAEA PLiM 2007 Symposium Shanghai, China, October 15-18, 18, 2007 Ageing Management and Safe Long Term Operation of Japanese Light Water Reactors Securing the Stability of Ageing Nuclear Power Plants Naoto Sekimura, Prof., Dr. Department of Quantum Engineering and Systems Science Department of Nuclear Engineering and Management The University of Tokyo

2 Contents General Background of LWR Ageing in Japan Regulatory Systems for Ageing Management Improved Ageing Management after Mihama-3 Accident Ageing Management Technical Evaluation and Regulatory Documents and Guidelines New Inspection System Strategy Maps for Ageing Management Technical Information Basis for Ageing Management Research Activities and Good Practices International Collaboration ( Impact of Earthquake to Kashiwazaki-Kariwa Plants ) Summary 2

3 Nuclear Power Plants in Japan : 55 units 1600 Electrical Output (MW) BWR : 32Units PWR : 23Units CGR, ATR 0 30 年 20 年 10 年現在 Start of Operation 3

4 Regulatory Inspection, Periodic Safety Review and Ageing Management Technical Evaluation Start of Commercial Operation Regulatory Inspection (every 13 Months) Utility s Periodic Safety Review (PSR) (every 10 Years) 10 Years 10 Years 10 Years 10 Years 10 Years Utility s Ageing Management Technical Evaluation for Long-Term Operation before 30 years of Operation Revaluation Every 10 Years 30 Years 10 Years 10 Years 4

5 Japanese Nuclear Regulatory Organizations NISA in METI established in Jan JNES established in Oct NSC 5

6 Committee on Ageing Management in NISA After the Mihama Unit 3 Accident on August 8, 2004, a Committee on Ageing Management was established in NISA. The Committee reviewed and discussed the basic policy, guidance documents, and the technical base for ageing management. Nuclear Power Plant Ageing Management Office (AMO) was established in NISA. Nuclear Power Plant Ageing Evaluation Office was established in JNES. 6

7 New Offices on Ageing Management in NISA and JNES from December, 2004 Nuclear Power Plant Ageing Management Office in NISA; Compilation of Regulatory Guidelines for Ageing Management Review of utility's Ageing Management Technical Evaluation Selection of Safety-related Research & Development, reflecting the Strategy Maps for Ageing Management Nuclear Power Plant Ageing Evaluation Office in JNES; Preparation of Standard Manuals and Procedures for Ageing Management Technical Evaluation Technical Evaluation of utility s Ageing Management report Preparation and Consolidation of Principal Database for AM Implementation of safety-related Research & Development 7

8 Report on Improved Ageing Management of NISA approved on August 31, 2005 The following issues can be considered necessary to improve ageing management. (1) To assure transparency and effectiveness (2) To provide a technical information basis (3) To prevent non-physical degradation (4) To offer clear accountability to the public Domestic and International Collaborative actions are encouraged to promote Ageing Management for Safe Long Term Operation. 8

9 Report on Improved Ageing Management of NISA approved on August 31, 2005 Needs for various types of safety researches are also emphasized. R&D Roadmaps for Ageing Management and Safe Long Term Operation developed by the Atomic energy Society of Japan are the excellent references for these wide variety of safety research. Industries, government and research organization including universities are required to collaborate and share their roles effectively. 9

10 Ageing Management Technical Evaluation on the 3 rd and following PSR Review on Operational Experiences and Ageing Phenomena in SSC Reflect Latest Database and Technological Knowledge Assumption of Service for 60 years Prepare Long-Term Maintenance Programs 10

11 Ageing Management Technical Evaluation by Utilities 1. Classification of SSCs and Ageing Phenomena 1.1 Categorizing, Classifying and Grouping of SSCs 1.2 Clarification of Ageing Phenomena 2. Technical Evaluation of Ageing Management 2.1 Technical Evaluation of Integrity of SSCs Evaluation by actual inspection and monitoring of data Analyses and calculation on the assumption of long-term operation 2.2 Review of Current Maintenance Program (CMMP) Preservation review of CMMP adequacy against ageing degradation of SSCs on the assumption of long-term operation 3. Long-term Maintenance Program 3.1 Confirmation of CMMP to be continued adequately 3.2 Clarification of additional maintenance program to CMMP and establishment of long-term maintenance program 3.3 Clarification of Research and Development tasks 11

12 Regulatory Guidelines, Standard Review Plan and Review Manuals for Ageing Management and Technical Evaluation Technical Document for Ageing Management Implementation of Nuclear Power Plants Ageing Management Implementation Guideline for Nuclear Power Plants 26 December 2005 Nuclear and Industrial Safety Agency (NISA) Standard Review Plan for Ageing Management Technical Evaluation of Nuclear Power Plants 26 December 2005 Nuclear and Industrial Safety Agency (NISA) Age-related Technical Evaluation Review Manual Neutron Irradiation Embrittlement of Reactor Pressure Vessel Revised, October 2006 Japan Nuclear Energy Safety Organization (JNES) Ageing Management Implementation Guideline Scope of the Guideline Implementation, Reevaluation and Revision of the Ageing Management Technical Evaluation (AMTE) Establishment, Reevaluation and Revision of Long-Term Maintenance Program (LTMP) Verification Processes of AMTE and LTMP by the Regulatory Authority Publication of the results of the Review by the Regulatory Authority and Other Matters Application of this Guideline Actions for Progress Standard Review Plan for Ageing Management Technical Evaluation Purpose Objectives Detailed Review Procedures of AMTE NISA: Review and Site Audit, Report to AMTE-WG JNES: Report Detailed Review Results on the Technical Evaluation Points of View and Criteria for Reviews Confirmations for Periodical Safety Review Age-related Technical Evaluation Review Manual Neutron Irradiation Embrittlement or Reactor Pressure Vessel Stress Corrosion Cracking(SCC) Fatigue Thinning of Piping Insulation Degradation of Electrical Cables of Instruments and Control Facilities Strength and Shielding Capability Degradation of Concrete Seismic Safety Evaluation Viewpoint and Understanding of Approaches to Prevention for Organization Culture Degradation 12

13 Ageing Management Implementation Guideline for Nuclear Power Plants (NISA) Ageing Management Implementation Guideline for Nuclear Power Plants Original in Japanese 26 December 2005 Nuclear and Industrial Safety Agency (NISA) Outline of Contents 1. Historical Background 2. Definition of Terminology 3. Scope of the Guideline 4. Implementation, Reevaluation and Revision of the Ageing Management Technical Evaluation (AMTE) 5. Establishment, Reevaluation and Revision of Long-Term Maintenance Program (LTMP) 6. Report of Ageing Management Technical Evaluation (AMTE) Results and LTMP to the Regulatory Authority 7. Implementation of LTMP and Report of its Results 8. Evaluation relating to Ageing Management at the Periodical Safety Review 9. Verification Processes of AMTE and LTMP by the Regulatory Authority 10. Publication of the results of the Review by the Regulatory Authority and Other Matters 11. Application of this Guideline 12. Actions for Progress (December, 2005) 13

14 Standard Review Plan for Ageing Management Technical Evaluation (NISA) Standard Review Plan for Ageing Management Technical Evaluation of Nuclear Power Plants Original in Japanese 26 December 2005 Nuclear and Industrial Safety Agency (NISA) Outline of Contents 1. Purpose Criteria and View-Points on Reviewing by NISA and JNES 2. Objectives Framework and Organization for AMTE AMTE Procedures 3. Detailed Review Procedures of AMTE NISA: Review and Site Audit, Report to AMTE-WG JNES: Report Detailed Review Results on the Technical Evaluation 4. Points of View and Criteria for Reviews Review of AMTE Review of Long Term Maintenance Program (LTMO) 5. Confirmations for Periodical Safety Review Measures against Ageing Degradation Phenomena in Maintenance Program Measures against Degradation of Organizational Safety Culture (December, 2005) 14

15 Standard Review Procedures of Ageing Management Technical Evaluation (1) Establish Implementation Framework for AM Technical Evaluation (2) Extract Class 1, 2 and 3 Components and Structures (CSs) Select one CS (3) Extract Consumables and Periodic Replacement Articles (4) Divide into Composed Parts of CSs by Considering Necessity for Achievement of its Function Out of Scope of Technical Evaluation (5) Active Parts No (6) Identify Materials used and Operating & Environmental Conditions on a Part to Part Basis (pressure, temperature flow conditions, operating conditions and structures ) Yes Appropriate Maintenance Management No Yes Out of Scope of Technical Evaluation (7) Select one Part and Extract All Ageing Degradation Phenomena to be occurred or that could not be negated Possibilities absolutely. (8) Extract Evaluation Points for One Ageing Degradation Phenomena (9) Evaluate Occurrence and Progress of the Ageing Degradation Phenomena on Evaluation Points (10) Focused Ageing No Degradation Yes (11) Evaluate Integrity Assumed up to 60 Year Operation Period (Structural and Functional Integrity) Continue Current Base Maintenance No No No (12) Appropriate Current Base Maintenance No (13) Establish a Long Term Maintenance Program Incorporated Additional Maintenance Program (14) Evaluate All Ageing Degradation Phenomena Yes (15) Evaluate All Parts of CSs Yes (16) Evaluate All CSs Yes Yes Continue Current Base Maintenance Completion (17) Evaluate Anti-Seismic Safety Considering Ageing Degradation (18) Appropriate Current Facilities No (19) Establish a Long Term Maintenance Program Incorporated Additional Maintenance Program Yes No Measure Needed 15

16 Technical Evaluation Review Manuals for Ageing Management (revised versions : October, 2006) Technical Document for Ageing Management of Technical Nuclear Document Power Plants for Ageing Management of Nuclear Power Plants Ageing Technical Evaluation Review Ageing Technical Manual Evaluation Document for Ageing Review Management Implementation of Manual Nuclear Power Plants Neutron Irradiation Embrittlement of Neutron Reactor Irradiation Pressure Embrittlement Vessel of Age-related Reactor Technical Pressure Evaluation Vessel Review Manual Neutron Irradiation Embrittlement of Reactor Pressure Vessel JNES - SS December 2005 December 2005 December 2005 Japan Nuclear December Energy 2005 Safety Organization Japan Nuclear December Energy (JNES) 2005 Safety Organization December (JNES) 2005 Original in Japanese Revised, October 2006 Japan Nuclear Energy Safety Organization (JNES) Conduct Detailed Review of Age- Related Technical Evaluation Compile Results of ARTEs conducted previously for 9 Plants and Latest Technical Knowledge Including the Following Manuals; JNES-SS Neutron Irradiation Embrittlement or Reactor Pressure Vessel JNES-SS Stress Corrosion Cracking JNES-SS Fatigue JNES-SS Thinning of Piping JNES-SS Insulation Degradation of Electrical Cables of Instruments and Control Facilities JNES-SS Strength and Shielding Capability Degradation of Concrete JNES-SS Seismic Safety Evaluation JNES-SS Viewpoint and Understanding of Approaches to Prevention for Organization Culture Degradation Note: The title of the manuals mentioned on my presentations is tentatively named for providing information. 16

17 Major Degradation Phenomena of Materials in LWR for Technical Evaluation of Ageing Management Neutron Irradiation Embrittlement of Reactor Pressure Vessel Stress Corrosion Cracking (SCC) IGSCC PWSCC IASCC Fatigue (including Environmental Fatigue) Thinning of Piping Flow Accelerated Corrosion (FAC) Liquid Droplet Impingement Erosion Flashing Erosion Cavitation Erosion Insulation Degradation of Electrical Cables of Instruments and Control Facilities Strength and Shielding Capability Degradation of Concrete 17

18 Technical Evaluation Review Manuals Neutron Irradiation Embrittlement of Reactor Pressure Vessel JNES-SS SS (revised in October, 2006) Contents Technical Document for Ageing Management Implementation of Nuclear Power Plants Technical Evaluation Review Manual for Ageing Management Neutron Irradiation Embrittlement of Reactor Pressure Vessel JNES - SS December 2005 December 2005 December 2005 December 2005 Japan Nuclear Energy Safety Organization (JNES) Original in Japanese Revised, October Introduction 2. Basic Guideline 3. Review Process 3.1Technical Evaluation Review Process for Ageing Management 3.2 Review of Long Term Maintenance Program 4. Reporting Items and Contents 5. Confirmation Items in Periodical Safety Review Appendix 1: Examples of Comparison of Surveillance Test Results and Embrittlemt Prediction Formula Appendix 2: Description of Typical Integrity Evaluation Process 18

19 Current Codes and Application of New Knowledge in the Technical Evaluation Review Manuals for Radiation Embrittlement JEAC Surveillance test method of structural materials for nuclear power reactors JEAC Verification test method of fracture toughness of components for nuclear power plants Introduction of Latest knowledge A new method based on mechanistically guided model developed by CRIEPI* can also be used to verify the prediction for possible variation of surveillance data. 19

20 Technical Evaluation Review Manuals on Fatigue JNES-SS SS (revised in October, 2006) Contents Age-related Technical Assessment Review Manual Fatigue JNES - SS December 2005 Technical Document for Ageing Management Implementation of Nuclear Power Plants Japan Nuclear Energy Safety Organization (JNES) 1. Introduction 2. Basic Guideline 3. Review Process 4. Reporting Items and Contents 5. Confirmation Items in Periodical Safety Review Appendix 1: Results of Low Cycle Fatigue Evaluation during 60 Year Operation (for Nine Plants) Appendix 2: Operating Years and the Number pf Occurrence of High Cycle Fatigue Original in Japanese 20

21 Technical Evaluation Review Manuals on Seismic Safety Assessment JNES-SS SS (revised in October, 2006) Contents Age-related Technical Assessment Review Manual Seismic Safety Evaluation JNES - SS October 2006 Technical Document for Ageing Management Implementation of Nuclear Power Plants Japan Nuclear Energy Safety Organization (JNES) Original in Japanese, Revised in October Introduction 2. Basic Policy 3. Seismic Safety Evaluation Process 3.1 Selection of Components 3.2 Arrangement of Safety Impotence 3.3 Selection of Ageing Degradation Phenomena 3.4 Seismic Safety Assessment for Every Age-related Degradation Phenomena 3.5 Evaluation of Active Function during Earthquake 3.6 Application to All Components 3.7 Selection of items to be incorporated into the Maintenance Measures 4. Reporting Reference Documents (1) Trend of Codes relative to Seismic Design (2) Example of Seismic Safety Assessment Processes for Every Age-related Degradation Phenomena (3) Examples of Modeling for each age-related Degradation Phenomena and Allowable limits in Seismic Safety Assessment (4) Evaluation Process of Seismic Safety Assessment on Pipe Thinning 21

22 Current Safety Regulation for Maintenance and Ageing Management Maintenance Management Ageing Management Policies and goals of maintenance management Maintenance Establishment of the scope Long-term maintenance plan Improvements Establishment of maintenance programs Inspection & repair Confirmation & assessment of inspections & repairs No Correction Yes Periodical assessment of maintenance Periodic Safety Review (PSR) every 10 years Ageing Management Technical Evaluation Assessment in 30 th year and reassessment less than every 10 years thereafter Establishment and Revision of Long-Term Maintenance Programs * 1 After 30 years in operation Implementation of Long- Term Maintenance Programs as Periodic Inspection by Utilites* 2 *1 Legal requirements *2 Guideline requirements Report * 1 Technological Assessment, On-site inspections * 2 Report * 1 Technological Assessment, On-site inspections * 2 Report of the results after each inspection * 1 Confirmation through periodic inspections and safety management assessment * 1 Regulator for Nuclear Safety 22

23 Regulator for Nuclear Safety New Safety Regulation for Maintenance Program and Ageing Management Continued improvement of maintenance management (Revision)Application Safety regulations based on the Nuclear Reactor Regulation Act (Revision) Application Notification Safety regulations based on the Electric Utility Act Confirmation of contents and implementation Maintenance Program Basic Items Maintenance plan Management of maintenance activities, setting of indicators, establishment of monitoring plans Management of maintenance activities, monitoring of indicators Policies and goals of maintenance management Establishment of the scope Establishment of the importance Implementation Collecting maintenance data, checking, tests, inspections, repair, replacement, remodeling Validity assessment of maintenance Establishment of plans Yes Confirmation & assessment of inspections & repairs No Management of incompatibility, correction Validity assessment of maintenance management Ageing Management Periodic Safety Review (PSR) every 10 years Ageing Management Technical Evaluation Assessment in 30 th year and reassessment less than every 10 years thereafter Establishment of Long-Term Maintenance Programs After 30 years in operation and thereafter Implementation of Long-Term Maintenance Programs

24 Technical Information Basis for Ageing Management Ageing Management Ensuring the safety and reliability of NPPs Implementation of effective safety regulations Establishment of maintenance technologies Formulation of evaluation standards and methods Accumulation and utilization of knowledge and data Development of Technical Information Basis Reflection of necessity, importance, and urgency of R&D 2. Research and Development 1 Inspection and monitoring technologies 2 Preventive maintenance, and repair technologies 3 Evaluation technology for materials degradation 1. Technical Information 1 Umbrella aging information 2 Plant operation experiences 3 Scientific information, etc. Reflection of Investigation and R&D results Synthetic Technical Information Basis Sharing and utilization by industry, government and academia 24

25 A Coordinating Committee on Ageing Management was established with members from industries, utilities, research organization and regulatory authorities. Information Exchange Umbrella Network Industry Technical development Plant information, etc. Safety research Information on regulations, etc. Government Comprehensive coordination Basic research Scientific information, etc. Academia Other Industries Technical Information Base International Projects 25

26 Continuous Revision of Strategy Maps for Ageing Management by All the Stakeholders Safety Research Sub-Committee in the Coordinating Committee on Ageing Management Strategy Maps for Ageing Management 1Introduction Scenario Needs Targets Milestones Periodic Revision through Latest Knowledge 2Maps of Technical Issues 3Roadmaps Nuclear Safety Regulatory Standard Committee in NISA Publicity R&D projects Information Basis Hardware Resources Human Resources Comments & Participation Publication Budgetary Actions for Research and Infrastructure Regulation Systems with Codes and Standards 26

27 R&D Roadmaps for Ageing Management and Safe Long Term Operation developed by Atomic Energy Society of Japan in To Keep Safety and Reliability of Nuclear Power Plants for Long Term Operation Establishment of Information Basis Technical Development Codes and Standards Systematic Maintenance Database for Degradation of Materials Evaluation Technology for Degradation of Components Standardization of Ageing Management Procedures Optimization of Maintenance Systematic Ageing Management Program Database on Regulation Procedures In Other Countries IASCC RPV Radiation Embrittlelment Schemes To Apply New Techniques Performance Index Risk-based Maintenance Human Resources 27

28 Major Roles of Industries, Government and Academia for Ageing Management Academia Responsibility to contribute to safety research activities - to accumulate and expand fundamental knowledge - to keep human resources through the safety research Government Responsibility to establish and improve safety regulations - by conducting safety researches, - by keeping infrastructure Responsibility to promote nuclear energy for national energy security Industries Primary responsibility to keep safe operation of power plants - research and development, and development of the infrastructure for safety and public interests Academic Societies To develop, review strategy maps periodically and build a consensus with experts from industries, government and academia by identifying important issues to be solved by discussing roles of stakeholders for rational and efficient implementation of research To develop and improve codes and standards based on safety research outcome 28

29 Strategy Maps 2007 for Ageing Management Scenarios(1) Ageing Management Technical Evaluation for Every 10 Years - Increase in number of plants From initial plants to standardized plants 7 9 T1 1F2 7 6 T2 SM1 6 T1 GN1 5 SD F2 SD2 4 4 O OG H2 3 3 SM1 K1 3 I1 H2 1F6 Tsu1 1F1 3 H4 2F2 3 2 T1 2 M3 To2 O2 2 2 M2 SD1 2F3 M3 H3 To2 O1 M1 GN2 M2 K3 I3 2 Tsu F2 T2 1F3 1 1F4 1F6 Tsu1 1F1 2F2 OG1 T4 1F3 2F4 1F4 TM1 K2 O2 2F1 SK1 K4 1 M1 1F1 M2 0 SM1 GN1 H1 I1 1F5 O1 M1 GN2 I2 0 2F2 T3 H1 Tsu2 1F5 SM2 K5 TM2 I2 O4 GN3 Year Note: This figure is drawn assuming that all of the plants currently in service will continue their operation. First plant to exceed 40 years of operation First plant to exceed 50 years of operation 29

30 Strategy Maps 2007 for Ageing Management Scenarios (2) Ageing Management of Current LWR Plants and their Replacements Assuming 60 years of operation of current LWR LWR Capacity [ten-thousand kw] Year 30 % of Total Electricity From METI s Nuclear Energy Subcommittee Japanese Nuclear Energy National Plan August, 2006 Installed capacity [ten-thousand kw] The long-term operation of existing plants A plant with operating experience of 40 years and above appears. Newly-built light water reactors Fast Breeder reactors * These values are estimated based on the comparison of total generated electric energy with that of 2014 estimated on the assumption that the utilization rate of 75%. Year From the survey by the Agency for Natural Resources and Energy of METI 30

31 Strategy Maps 2007 for Ageing Management Aging phenomenon Irradiation embrittlement Stress corrosion crack Maps for Technical Issues 4. Systematic Maintenance 3. Establishment of Information Basis 2. Establishment of Codes and Standards 1. Safety Research to Solve Ageing Issues Current Status * Countermeasures are being taken by rule of thumb based on plant data. * Countermeasures suited to materials in use are being taken. * Database is being constructed. 40 th to 50 th year * Predication methods and monitoring technology will be upgraded. * Use of SCC-resistant materials will be ensured. * Database will be constructed. Long-life, nextgeneration reactor * Advanced designs will be developed based on past operating experience. * Simulation methods will be established. * ISI technology will be upgraded. Fatigue * Countermeasures suited to materials in use or environment are being taken, and database is being constructed. * Countermeasures suited to materials in use or environment will be taken, and database will be constructed. * Countermeasures suited to materials in use or environment will be taken, and database will be constructed. Wall thinning * Countermeasures suited to materials in use are being taken, and database is being constructed. * Mechanism-based predication methods will be established. * Risk-based maintenance methods will be established. * Monitoring technology will be upgraded. Deteriorated cable insulation * Countermeasures suited to materials in use are being taken. * Database is being constructed. Deterioration diagnosis technology will be upgraded. * Monitoring technology will be upgraded. Decreased strength of concrete Intensive study is being made on scarcely known fields. The reliability of integrity evaluation methods will be improved or enhanced. CCV integrity evaluation methods will be established. * Past records of performance will be reflected in the maintenance technology and durability designs for new plants. * Recycling methods will be established for replaced structures and materials. 31

32 Strategy Maps 2007 for Ageing Management Roadmaps for Stress Corrosion Cracking 6. Repair & Replacement Technologies 5. Monitoring Technologies on SCC 4. Inspection Technologies on SCC 3. Integrity Evaluation : NiSCC 2. Integrity Evaluation : IGSCC 1. Integrity Evaluation : IASCC Fiscal Year Phase I (until 40 year operation of early stage NPPs Phase II (until 50 year operation) Phase III (until 60 year operation) ~ ~2029 Preparation and refinement of initiation data and crack growth data on IASCC Preparation of infrastructure for IASCC research Preparation and refinement of initiation data and crack growth data on IASCC Confirmation of the data and evaluation technology, and preparation of regulatory criteria Understanding of IASCC mechanism Simulation technology of IASCC initiation and propagation IASCC initiation test methods Extended IASCC crack initiation data and its refinement IASCC evaluation technology confirmation Refurbishment of laboratory facility including JMTR Aps Extended IASCC crack growth data and its refinement Correlation between laboratory data and field events Study of accelerated irradiation validity Obtaining of crack growth data for ex-plant materials In-core IASCC Initiation and growth evaluation Understanding and modeling of IASCC crack Understanding and modeling of IASCC crack initiation and growth mechanism Development of simulation technology of IASCC initiation and growth Study of IASCC mechanism at high fluence region Establishment of code and standards, and regulatory criteria Establishment of CS for fitnessfor-service IASCC integrity evaluation guide Establishment of CS for fitness-for-service Coding of IASCC initiation and growth simulation SCC long term integrity evaluation guide 32

33 Strategy Maps 2007 for Ageing Management Roadmap of Research and of Code Development for IASCC Fiscal Year Phase I (until 40 year operation of early stage NPPs Phase II (until 50 year operation) Phase III (until 60 year operation) ~ ~2029 IASCC initiation test methods Preparation and refinement of initiation data and crack growth data on IASCC Preparation of infrastructure for IASCC research Preparation and refinement of initiation data and crack growth data on IASCC Confirmation of the data and evaluation technology, and preparation of regulatory criteria Understanding of IASCC mechanism Simulation technology of IASCC initiation and propagation Extended IASCC crack initiation data and its refinement IASCC evaluation technology confirmation Refurbishment of laboratory facility including JMTR Extended IASCC crack growth data and its refinement Correlation between laboratory data and field events Study of accelerated irradiation validity Obtaining of crack growth data for ex-plant materials In-core IASCC Initiation and growth evaluation Understanding and modeling of IASCC crack Understanding and modeling of IASCC crack initiation and growth mechanism Development of simulation technology of IASCC initiation and growth Study of IASCC mechanism at high fluence region Establishment of code and standards, and regulatory criteria Establishment of CS for fitnessfor-service IASCC integrity evaluation guide Establishment of CS for fitness-for-service Coding of IASCC initiation and growth simulation SCC long term integrity evaluation guide 33

34 Development of Technical Information Infrastructure Development of Codes and Standards Systematic Maintenance Improvement Safety Research & Development Technical Evaluation Result Latest Information Selection of Research Theme Research result Latest Information -Maintenance Information -Case Maintenance -Operating Experience Technical Information Infrastructure Tacit Knowledge Tools for Education Human Resources 34

35 Basic Structure of the Strategy Maps Dynamical Use of Knowledge Development of Codes & Standards Effective regulation Improvement of current standards and criteria Academic Meaning of the Strategy Maps Development of Technological Information Infrastructure Information system of ageing International collaboration Establishment of the information network securing disinterested party and responses to internationalization Structurization of Knowledge Promotion of Technology Development Assessment and promotion of safety research and technology development Systematic technology development based on the roadmap followed by review Realization of knowledge Systematic Maintenance Improvement Improvement and education of integrated maintenance Development of optimized maintenance plan Education to keep human resource Social Environment and Business Environment 35

36 Recent Progress of Research Coordination and Safety Research Projects in Japan A Coordinating Committee on Ageing Management was established with members from industries, utilities, research organization and regulatory authorities. Research Projects on Fundamentals of Ageing Management funded by NISA started from 2006 in 4 districts in Japan. Organized R&D projects by Utilities have started. 36

37 Industrial Efforts to Promote PLM-related R&D Activities * Technology information coordination committee Chairman and deputy chairman of promotion council board participate in the committee. <The Federation of Electric Power Companies of Japan> Nuclear energy development committee PLM research promotion council board Policies regarding research promotion [Secretariat: JANTI (FEPCO)] Collaboration Nuclear energy development committee Comprehensive task force PLM research administrative review meeting Discussing research strategies [Secretariat: CRIEPI] Evaluation results Providing future directions Collaboration Equipment maintenance committee 10 Sub Group (SG): Examination team Individual Issues. * Kamada et al; this Symposium <Electric power companies, manufacturers and organizations that are involved in the support system> Nine electric power companies, JAPC, Electric Power Development CO., CRIEPI and JANTI 37

38 Research Project on Fundamentals of Ageing Management NISA (Nuclear and Industrial Safety Agency) in METI Tohoku Cluster ICR Fukui Cluster INSS East Japan Cluster MRI Ibaraki Cluster JAEA Information Exchange Progress Report Advice Progress Report Advice General Review Session on Ageing Management Infrastructure Improvement General Review Session WG Review Session on Ageing Management Database and Knowledge Base Review Session on Seismic Effects on Piping Thinning Review Session on Condition Monitoring and Safety Preservation Technology Review Session on Irradiation Embrittlement Review Session on Cable Degradation Technical Information Outcome Coordination Committee Safety Research WG In JNES Information Exchange Academic Societies etc. Review Session on Stress Corrosion Cracking 38

39 OECD/NEA SCAP Project * SCAP: Stress Corrosion Cracking and Cable Ageing Project The main objectives of SCAP are to: Establish a complete database with regard to major ageing phenomena for SCC and degradation of cable insulation through collective efforts by OECD/NEA members Establish a knowledge-base by compiling and evaluating collected data and information systematically, with regard to major ageing phenomena for SCC and degradation of cable insulation Perform an assessment of the data and identify the basis for commendable practices which would help regulators and operators to enhance ageing management *Yamamoto et al; this Symposium 39

40 Management of the SCAP MB Chair Prof.Sekimura (Japan) SCC WG SCC Chair Mrs. Gott (Sweden) Clearing House ERIN(U.S) Management Board SCAP Consultant Mr. Shultz (Germany) Cable WG Cable Chair Mr. Koshy (U.S) Clearing House OECD Halden Reactor Project IFE(Norway) (Members) Belgium Canada Czech Republic Finland France Germany Japan Korea Mexico Norway Slovak Republic Spain Sweden U.S (Observers) IAEA, EC Technical Secretariat 40

41 Kashiwazaki-Kariwa Kariwa Nuclear Power Plants 7 units, 8,212 MWe Reactor type Units 1-5: BWR Units 6, 7: ABWR 41

42 Layout of Kashiwazaki-Kariwa Kariwa site 42

43 Kashiwazaki-Kariwa Kariwa Nuclear Power Plants Unit Start of Operation Type Output Main Contractor No /9/18 BWR-5 1,100MWe / 3,293MWt Toshiba No /9/2 BWR-5 1,100MWe / 3,293MWt Toshiba No /8/11 BWR-5 1,100MWe / 3,293MWt Toshiba No /8/11 BWR-5 1,100MWe / 3,293MWt Hitachi No /4/10 BWR-5 1,100MWe / 3,293MWt Hitachi No /11/7 ABWR 1,356MWe / 3,926MWt No /7/2 ABWR 1,356MWe / 3,926MWt Total 8,212MWe Toshiba/Hitachi/ GE Toshiba/Hitachi/ GE 43

44 Chuetsu-Oki Earthquake on July 16,2007 July 16, :13AM JST (GMT+9) (National Holiday) Magnitude on the Richter scale: 6.8 Distance from the Kashiwazaki-Kariwa Site Epicenter :16 km, Hypocenter : 23 km, (Depth: 17 km) 30km Epicenter Sea of Japan 10km KK site Pacific Ocean Google ZENRIN Distribution of seismic intensity (JMA) 44

45 Damage to the Roads Inside the Site Road damage near K-5 Road damage near Switch Yard

46 Operational Status of the Units on July 16,2007 Unit 1 Unit 2 Unit 3 Unit 4 Unit 5 Unit 6 Unit 7 Status before earthquake Outage Startup (subcritical) At Full Power At Full Power Outage Outage At Full Power Automatic shutdown Yes Yes Yes Yes Status after earthquake Cold shutdown Cold shutdown Cold shutdown Cold shutdown Cold shutdown Cold shutdown Cold shutdown Off-site power 2 out of 4 lines were maintained during and after the quake Diesel generator Good (Stand-by) Good (Stand-by) Good (Stand-by) Good (Stand-by) Good (Stand-by) Good (Stand-by) Good (Stand-by) 46

47 Post-Seismic Plant Conditions - Reactor Pressure Vessel Foundation Bolts - No damage was observed by visual check of the RPV foundation bolts Reactor pressure vessel Skirt Pedestal Foundation bolt 47

48 Post-Seismic Plant Conditions - MSIV and PLR Pump - Main steam isolation valves (in primary containment vessel) Recirculation pump (in primary containment vessel) 48

49 Review Team IAEA Expert Mission on August 6-10, JAMET, Philippe: IAEA/NSNI/Director, Team Leader GODOY, Antonio R.: IAEA/NSNI/ESS, Deputy Team Leader GUNSELL, Lars: SKI, Sweden JOHNSON, James J.: James J. Johnson & Associates, USA KOSTOV, Marin: Risk Engineering Ltd., Bulgaria 49

50 IAEA Mission Report (1) 1. The trip of all the reactors which were at full power or increasing power was performed without problem and the installation behaved in a satisfactory manner during and after the earthquake. The three fundamental safety functions (reactivity control, removal of residual heat and confinement) were insured. 2. Although an extremely small amount of radioactive material was released, the resulting individual dose was estimated well below the authorized limits. 3. Although the safety related structures, systems and components of the plant suffered from the large earthquake, they seem to be in a much better general condition than expected. This is probably due to the conservatisms taken into account at different stages of the design process. 4. In the re-evaluation complying with the September 2006 guidelines issued by NSC, the investigations are also to address the issue of the potential existence of active faults under the site. 5. The possibility should be considered that the systems and components remain functionally available under normal operating conditions but sustain hidden damage. 50

51 IAEA Mission Report (2) Specific issues indicated in the Report Exceeding of the Design Basis Ground Motion by the Observed Earthquake Re-evaluation of the Seismic Hazard Off-Site Power Common-Cause Failure Fire Safety Seismic System Interaction Soil Failures Anchorage Failures Operational Safety Management Releases Ageing 51

52 A New Advisory Committee in NISA - A Working Group for Reactor Management and Systems Integrity - (1) Operation and Management of the Plant Systems Evaluation of measures for operation management conducted by the licensee immediately after the earthquake disaster; extraction of problems; and demanding the licensee to reflect the problems in their manuals when needed. (2) Examination of Integrity of SSCs Examination of necessary inspection, and evaluation of inspection plans and results by TEPCO Examination of evaluation methodology for equipment integrity, and criteria for necessary repair or replacement actions Examination of a method for maintenance and repair, based on the results of inspection and evaluation Extraction of items to be reflected in guidelines and criteria in the courses of individual examinations 52

53 Summary (1) Current status of ageing management of Japanese light water reactors is briefly stated. Regulatory systems and documents for technical evaluation procedures of safe long term operation have been continuously improved and up-dated. New regulatory inspection system will start next year, which can improve and strengthen maintenance and ageing management of Japanese light water reactors. Continuous revision of Strategy Maps for Ageing Management and Safe Long Term Operation by all the stakeholders has been performed under the Coordinating Committee of Ageing Management. 53

54 Summary (2) Intensive safety research collaborations have been performed accompanying the following activities; Systematic Development of Information Basis for Database and Knowledge-base Development of Codes and Standards by Academic Societies International Contribution and Collaboration Effective Sharing and Collaboration between Industries, Government and Academia Regulatory activities for Chuetsu-oki earthquake which caused temporary shutdown of the Kashiwazaki-Kariwa Kariwa plants were briefly explained. 54

55 Thank you very much.

56 Preliminary Announcement ISaG2008 2nd International Symposium on the Ageing Management & Maintenance of Nuclear Power Plants Tokyo, Japan, July or August 2008 ISaG Organizer: Research Strategy Committee of NISA Project on Enhancement of Ageing Management and Maintenance of Nuclear Power Plants First announcement: November 2007 Call for Paper: January 2008 Registration: April 2008 Topics: Building intelligence infrastructure on ageing and maintenance management, R&D activities, Standardization of technical information, Advancement and optimization of maintenance management in the industries and regulatory body, etc. Information: mailto:

57 ISaG 2008 Preliminary Announcement ISaG2008 2nd International Symposium on the Ageing Management & Maintenance of Nuclear Power Plants Tokyo, Japan, July or August 2008 Organizer: Research Strategy Committee of NISA Project on Enhancement of Ageing Management and Maintenance of Nuclear Power Plants First announcement: November 2007 Call for Paper: January 2008 Registration: April 2008 Topics: Building intelligence infrastructure on ageing and maintenance management, R&D activities, Standardization of technical information, Advancement and optimization of maintenance management in the industries and regulatory body, etc. Information: mailto:

58 ISaG 2008 Preliminary Announcement ISaG2008 2nd International Symposium on the Ageing Management & Maintenance of Nuclear Power Plants Tokyo, Japan, July or August 2008 Organizer: Research Strategy Committee of NISA Project on Enhancement of Ageing Management and Maintenance of Nuclear Power Plants First announcement: November 2007 Call for Paper: January 2008 Registration: April 2008 Topics: Building intelligence infrastructure on ageing and maintenance management, R&D activities, Standardization of technical information, Advancement and optimization of maintenance management in the industries and regulatory body, etc. Information: mailto: