Post-Fukushima Actions in Korea

Transcription

1 Post-Fukushima Actions in Korea IAEA TWG-LWR Vienna, June 18-20, 2013 Presented by Jong-Tae Seo

2 1. Impacts on National Energy Policy and NPP Plan 2. Actions Taken after Fukushima Accident 3. Findings and Improvements 2/28

3 1. Impacts on National Energy Policy and NPP Plan 3/28

4 1. Impacts on National Energy Policy and NPP Plan Emotional Impact as a neighboring country People were very sensitive to radiation risks from neighboring country s accident Reasonable explanation overshadowed by exaggerated radiation risks Hourly flash news on Fukushima thickening confusion and anxiety Negative public opinions on the nuclear energy Technical Impact of Fukushima accident Strong concerns about the nuclear safety caused by Real situation : Core Melt and consequent Hydrogen Explosions Prompt Response was required To confirm NPP Safety, and to protect and ease people Immediate activation of emergency response center Early implementation of Special Safety Inspection(SSI) 4/28

5 Installed Capacity Generation Share Installed Capacity Generation Share 1. Impacts on National Energy Policy and NPP Plan Future Plan Unchanged with Possible Adjustment National Energy Master Plan by 2030? 59% New 5&6 APR+ TBD units In Operation? 41% New 3&4 New 1&2 SKN 7&8 APR+ APR+ APR+ TBD TBD 2022/2023 SUN 3&4 APR /2021 SKN 5&6 APR /2019 Future Units 35% SUN 1&2 APR /2017 SKN 3&4 APR % 20 units SWN 1&2 OPR /2012 In Operation SKN 1&2 OPR /2011 Units Under Construction 2013/2014 5/28

6 2. Actions Taken after Fukushima Accident Response of Korean Government Emergency Response of Korean Government Setting up Emergency Response Center in KINS at 18:40 of Mar.11 Constructing Government Task Force Team under Prime Minister on Apr. 6 Protective Action for residents and travelers in Japan Radiation monitoring of territory and environment Special Safety Inspection (SSI) to Korean Nuclear Facilities Strong pressure from the public, media, residents near plants, and political society Started 10 days after the Fukushima accident by NSC (Nuclear Safety Committee) Inspection team with Nation-side experts and KINS staffs 6/28

7 2. Actions Taken after Fukushima Accident Emergency Response Center 7/28

8 2. Actions Taken after Fukushima Accident Government Task Force 8/28

9 2. Actions Taken after Fukushima Accident Special Safety Inspection (SSI) Government led SSI SSI performed to 21 operating NPPs, a research reactor and fuel cycle facilities Inspection period : Mar.21 ~ Apr.15, Review of Findings : Apr.16~Apr.30 Hearing with residents near NPP sites Objectives of SSI To determine design bases and design features against natural hazards To evaluate severe accident prevention and mitigation capabilities To determine effectiveness of emergency response systems SSI Scenario Earthquake Tsunami Power loss Severe accident 9/28

10 2. Actions Taken after Fukushima Accident SSI Team and Inspection Area 10/28

11 2. Actions Taken after Fukushima Accident Response of Utility - KHNP Korean Utility s Voluntary Inspection Started 5 days after Fukushima accident Focused on plant safety against beyond design basis natural hazards Inspection Team and Objectives 44 experts including operators, designers, and suppliers Inspected for all 21 operating NPPs Major Inspection Area : On- and Off-site Power availability, Reactor Core Coolability, Containment Integrity, and Spent Fuel Pool Integrity Major Findings Identified additional Improvement items beyond Government led SSI Findings 11/28

12 2. Actions Taken after Fukushima Accident Reorganization of Regulatory Body Nuclear Safety and Security Commission (NSSC) Started on October 26, 2011 Independent Organization directly under the President of Korea Replacing former Nuclear Safety Committee under Prime Minister Integrated Regulatory Review Service (IRRS) First IRRS by IAEA was performed in July 2011 Acknowledged reorganization of Regulatory Body To further improve regulatory system, several recommendations were suggested 12/28

13 1-1. Seismic Resistance Current status : 3. Findings and Improvements Special Safety Inspection Results (1/8) Sufficient safety margin exists for all units against maximum potential earthquake Design Basis SSEs for OPR-1000: 0.2g, for APR-1400: 0.3g Need for securing a safe shutdown capability even in case of an earthquake exceeding design basis SSE Improvements (5 items) : Install an automatic seismic trip system when the detected earthquake ground motions exceeds a certain level (0.18g) (all plants) Upgrade seismic capacity of the safe shutdown systems to the design earthquake level of advanced NPPs (0.3g) (all plants) Conduct a comprehensive re-assessment of the maximum potential earthquake at NPP sites (all plants) 13/28

14 1-2. Tsunami Resistance Current status : 3. Findings and Improvements Special Safety Inspection Results (2/8) Units are located on 10m above sea level for Yonggwang and Ulchin, 12m for Wolsong, 7.5m for Kori Units 1&2, 9.5m for Kori Units 3&4 Maximum potential sea water levels: 5.7m~8.4m Sufficient safety margin exists for all units against maximum potential sea water levels Narrowest margin is 0.3m for Kori Units 1&2 Improvements (4 items) : Extension of the sea wall height for the Kori site, whose freeboard is relatively low, to increase the height level equivalent to other sites (10m) (Kori site) Install seismically designed waterproof gates and waterproof drain pumps in the structures containing emergency power systems and major safety systems for inundation protection. (all plants) Investigate the maximum potential tsunami near Korean peninsula (all plants) 14/28

15 2. Reliability of Power Supply and Cooling System Current status : 3. Findings and Improvements Special Safety Inspection Results (3/8) To cope with Loss of Offsite Power and Station Black Out, 2 EDGs per unit (7 days operation) 1 AAC DG per 2 or 4 units (8 hrs operation) Multiple sources of water (RWST, CST) for emergency cooling of spent fuel pool Improvements (11 items) : Equip with one vehicle-mounted portable emergency power generator and batteries (including charger and cables) per site, and placing them in a safe location away from inundation (all plants) Upgrade the AAC diesel generator's design basis : increasing capacity, diversifying its cooling methods, ensuring one-day fuel storage (all plants) Prepare a supplementary connection for supplying water by using a fire vehicle in preparation for loss of cooling pump and heat exchanger in SFP (all plants) 15/28

16 3. Response to Severe Accidents Current status : 3. Findings and Improvements Special Safety Inspection Results (4/8) Facilities against severe accidents continuously supplemented at the operating plants as well as the plants under construction according to the Policy on Severe Accidents (Aug. 2001), Operator s capability of responding to severe accidents increased by establishing the Severe Accident Management Guidelines (SAMG). Various kinds of hydrogen removers(igniters, re-combiners, PAR) in containment (except Wolsong Unit 1) Improvements (6 items) : Install the passive hydrogen removal system (all plants except Kori Unit 1 ). Install filtered vent or depressurizing facilities to prevent containment overpressurization (all plants). Install primary and secondary injection flow paths for emergency cooling water injection in preparation for prolonged loss of cooling functions (all plants). Strengthen operator training for severe accidents (all plants). 16/28

17 4. Emergency preparedness and medical treatment Current status : 3. Findings and Improvements Special Safety Inspection Results (5/8) Appropriate emergency measures, including organization, facilities, protective action guidelines Regular exercises and drills Designated medical treatment centers for radiation emergency Need for enhancing current emergency response system to respond effectively to simultaneous emergency at multiple units in one site Improvements (11 items) : Amend the emergency plan to include emergency response organization that can be implemented at simultaneous natural disaster emergencies at multiple units Conduct emergency exercise using a practical scenario including earthquake and tsunami, and further increase emergency response capabilities through unannounced blind exercises. ( all NPPs). Improve the seismic capacity of TSC and OSC (Kori site), and anti-inundation ability ( Kori site, Yonggwang Unit-1&2) 17/28

18 5. Long-term in-service plants Current status : 3. Findings and Improvements Special Safety Inspection Results (6/8) Nine plants with over 20 years of operation were inspected to confirm aging effect The integrity change due to aging of safety-related piping as well as the reactor vessel has been verified through to the long-term in-service inspection program. The performance of the active components (pumps and valves) has been verified through the in-service test program and plant technical specification Additionally, the precision inspection was performed for the Kori Unit 1 due to the unplanned reactor trip. Improvements (10 items) : Re-inforcie the in-service inspection of the main components and pipes Establish and implement an integrated aging management program (Kori Unit-1) Increase the reliability of shutdown-precursor equipments (all plants) 18/28

19 6. Research reactor and nuclear fuel cycle facilities Current status : 3. Findings and Improvements Special Safety Inspection Results (7/8) HANARO research reactor building and stack were designed against around an earthquake of 0.2g and established radiological emergency plan for it The radiological emergency plans for nuclear fuel processing facilities was established, and radiological emergency alarm criteria was classified in terms of the event type Improvements (3 items) : Evaluate the seismic capacity and improve the main control room of Hanaro beyond DBE Re-evaluate the site's inundation depth for Hanaro and auxiliary facilities Amend the radiological emergency plan to reflect complicated radiological emergency conditions Simultaneous accidents at multiple facilities and a radioactive materials release, and reflect these into the radiological emergency plan (Hanaro and fuel processing facilities). 19/28

20 7. Summary and Follow-up Action Plan Summary A total of 50 short- and long-term safety improvement items identified. Implementation of improvement items was enforced by Nuclear Safety Committee (May 6, 2011). Licensee shall submit the detailed implementation plan within two months, and the progress report every six months thereafter Increased periodic regulatory inspection, verification of safety by the regulatory body for all reactor trips, and enhanced public participation were also enforced. Follow-up actions for improvement 1st Phase : Execution of SSI, and follow-up of short- and long-term improvements 2nd Phase : 3. Findings and Improvements Special Safety Inspection Results (8/8) Initiation of a project on feedback of lessons-learned from Fukushima ( 11.7-) Additional inspection and recommendations, International cooperation 3rd phase : Feedback from the international community Long-term cooperative research programs on severe accidents 20/28

21 3. Findings and Improvements Progress of Korean Response to Accident 21/28

22 3. Findings and Improvements KHNP s Voluntary Safety Improvement Items recommended by International Community 1. Safety grade SFP instrumentation : Temperature, Water Level, Radiation Detectors 2. Tech. Spec. upgrade to ensure backup power for SFP 3. Portable (or Mobile) diesel engine driven water pump 4. Long range water hose for emergency water supply 5. Emergency communication equipments such as wireless phone or satellite phones Items recommended internally 1. Seismic evaluation for the raw water supply piping (Water dam to treatment room) 2. Additional Aux-Feedwater Storage Tank for Ulchin unit #1 3. Emergency power supply to the area air cooler for Wolsung unit #1 4. Develop Extended Damage Mitigation Guideline (EDMG) 5. Temporary Emergency Operating Guidelines reflecting improvements 22/28

23 3. Findings and Improvements KHNP s Implementation Status Implementation Plan SSI Items 46* Voluntary Items Total * 4 SSI items are not applicable to the Nuclear Power Plant All Required and Recommended Improvement Items will be implemented by 2015 Implementation progresses as planned 23/28

24 3. Findings and Improvements KHNP s Implementation Status Progresses Automatic Seismic Trip System Extension of Tsunami Wall for Kori Site Water Proof Gate and Door 24/28

25 3. Findings and Improvements KHNP s Implementation Status Implementation Progress for NPPs under Construction 10 items were identified to be implemented before completion for commercial operation Shin Kori 3&4 will complete following 10 improvements before Operating License 1-1 Installation of an automatic seismic trip system 1-4 Improve the seismic capacity of the main control room (i.e., the earthquake occurrence alarm window) 2-2 Installation of waterproof gates and discharge pumps 3-1 Secure the availability of a portable electric power generator vehicle and batteries, etc 3-2 Upgrade design basis of AAC diesel generator 3-5 Ensure countermeasures against loss of the spent fuel pool cooling function 3-6 Prepare measures of the inundation prevention and restoration of the ultimate heat sink 3-7 Prepare countermeasures for damage of the outdoor tank 3-10 Improve fire protection facilities and response capability of plant firefighting team 4-3 Installation of reactor injection flow paths for emergency cooling water injection from external source Other units under construction will also implement as much as practically achievable before their completion 25/28

26 Appendix : Full List of SSI Action Items (1/3) Item No. Description of Action Item Action 1-1 Installing an automatic seismic trip system short-term 1-2 Improving an seismic capacity of the safe shutdown system mid-&long-term 1-3 Investigation and study on the maximum potential earthquake for NPP sites mid-&long-term 1-4 Improving the seismic capacity of the main control room (i.e., the earthquake occurrence alarm window) mid-&long-term 1-5 Improving the seismic capacity of the entrance bridge of Wolsong NPP short-term 2-1 Extension of the height of the sea wall for the Kori site short-term 2-2 Installation of waterproof gates and discharge pumps mid-&long-term 2-3 Investigating and research study on the design basis sea water lever of NPP sites mid-&long-term 2-4 Enhancement of the sea water intake capability and reinforcement of facilities in preparation for coastal flooding mid-&long-term 3-1 Securing the availability of a portable electric power generator vehicle and batteries, mid-&long-term 3-2 Upgrading design basis of AAC diesel generator mid-&long-term 3-3 Fastening the spare transformers with anchor bolts and modifying the fuel injection port of emergency power supply system short-term 3-4 Improving the management of switchyard facilities mid-&long-term 3-5 Ensuring countermeasures against loss of the spent fuel pool cooling function short-term 3-6 Preparing measures of the inundation prevention and restoration of the ultimate heat sink mid-&long-term 3-7 Preparing countermeasures for damage of the outdoor tank mid-&long-term 3-8 Preparing countermeasures for inundation of the main steam safety valve room and the emergency water pump room mid-&long-term 3-9 Improving the fire protection plan and reinforcing cooperation systems short-term 26/28

27 Appendix : Full List of SSI Action Items (2/3) 3-10 Improving fire protection facilities and response capability of plant firefighting team mid-&long-term 3-11 Introducing a performance-based fire protection design short-term 4-1 Installation of passive hydrogen removal equipment mid-&long-term Installation of filtered vent system or depressurizing facilities in the containment buildings. Installation of reactor injection flow paths for emergency cooling water injection from external sources mid-&long-term mid-&long-term 4-4 Reinforcing education and training for severe accidents short-term 4-5 Revision of the Severe Accident Management Guidelines to enhance effectiveness short-term 4-6 Development of Low-Power Shutdown Severe Accident Management Guidelines short-term 5-1 Securing additional radiation protection equipment for protecting residents near NPP short-term 5-2 Amending the emergency plan to include such events as a simu1taneous emergency at multiple units short-term 5-3 Securing additional protective equipment in preparation for a prolonged emergency short-term 5-4 Securing additional equipment of emergency medical institutes mid-&long-term 5-5 Reinforcing radiological emergency exercises short-term 5-6 Devising a means of securing the necessary information in case of a prolonged loss of electrical power mid-&long-term 5-7 Securing countermeasures for protecting maintenance workers short-term 5-8 Improving the emergency response facilities mid-&long-term 5-9 Amending the information disclosure procedures in the event of a radiation emergency short-term 5-10 Evaluating protective measures for residents who live beyond the emergency plan zone mid-&long-term 27/28

28 Appendix : Full List of SSI Action Items (3/3) 5-11 Reinforcing the performance of emergency alarm facilities mid-&long-term 6-1 Drastically reinforcing the safety inspections, such as regular inspections short-term 6-2 Reinforcing the in-service inspection of the main components and pipes short-term Establishing and implementing an integrated management method for the aging management program Reinforcing the management of the performance parameter of the main active components short-term short-term 6-5 Install a fatigue monitoring system to reinforce quantitative fatigue management mid-&long-term 6-6 Reinforcing the fatigue integrity of the pressurizer lower head short-term 6-7 Increasing the reliability of shutdown-inducing equipment short-term 6-8 Evaluating the adequacy of operators mid-&long-term 6-9 Increasing the reliability of station power supply systems mid-&long-term 6-10 Reinforcing the quality assurance on purchasing components important to safety short-term 7-1 Evaluating the seismic capacity and improving the main control room short-term 7-2 Re-evaluating the site's inundation depth for HANARO and additional facilities short-term 7-3 Amending the radiological emergency plan to reflect complicated radiological emergency conditions Total 50 short-term 28/28