DIRECTIONS FOR NUCLEAR SAFETY COOPERATION IN THE ASIA/PACIFIC REGION

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1 DIRECTIONS FOR NUCLEAR SAFETY COOPERATION IN THE ASIA/PACIFIC REGION Soon Heung Chang Department of Nuclear Engineering Korea Advanced Institute of Science and Technology Republic of Korea Introduction Securing the high level of safety is a pre-requisite for the sustained development and utilization of nuclear energy. Individual countries bear full responsibility for the safety of their nuclear facilities. However, it is apparent that the high level of nuclear safety can be effectively achieved through international cooperation rather than by independent efforts of individual countries. The benefit of cooperation would be more significant for regional countries with more shared interests and goals from their geological proximity. Most Asian countries are characterized by rapid economic growth and rapidly increasing demand of energy and electricity. Some Asian countries, including Japan, Korea, India and Taiwan, have developed ambitious nuclear power programs since the oil crises in 1970 s. Recently, China launched an active nuclear power programs and some other countries also started or considers the introduction of nuclear power plants (NPPs). At present, the region accounts for ~20% of nuclear power plants in operation and ~40% under construction in the world, as summarized in Table 1. It is also expected that further expansion of the world nuclear power capacity will occur mostly in Asian countries. In particular, the Northeast Asian countries have the most active nuclear power programs; this situation will continue to the early 21st century. Regional cooperation for nuclear safety can help individual countries in many ways. Safety of nuclear facilities can be enhanced by sharing experiences, helping each other to prevent severe accidents and to minimize accident consequences, etc. Cooperative safety research programs would enable the maximum and efficient utilization of experimental facilities, financial resources and manpower resources in the region. Countries with plans to newly introduce NPPs will be benefited from the support of advanced countries with strong technology and experience. In particular, close regional cooperation would also help enhancing public acceptance of nuclear power. This paper briefly discusses desirable directions for nuclear safety cooperation among countries in Asia. The major areas of possible cooperation would be: (a) harmonization of code and standards, (b) safety research, (c) safety review and inspection, (d) safety information and public acceptance, and (e) environmental assessment and 55

2 emergency cooperation. Some of discussions will be focusing on the Northeast Asian region, but most of them are applicable to the whole Asia/Pacific region. Areas of Cooperation Harmonization of Codes and Standards The need for nuclear safety is recognized globally, and a significant event at a nuclear facility in one country has the potential to affect its neighboring countries. Therefore, it is desirable to harmonize safety requirements and safety levels among regional countries. This can be achieved by cooperation between safety authorities, and assistance to the countries where regulatory organizations have to be strengthened. Table 1. Summary of Nuclear Power Programs in Asian Countries (as of Dec. 31, 1998) Japan Korea China Taiwan India Pakistan Iran Total World Share In Operation Units % MWe 45,082 12,016 2,268 5,144 1, , % Under Units % Construction MWe 2,205 5,700 3, ,000 15, % 1998 Nucl. TWh % Generation % The safety goals, general safety objectives, general safety principles, and toplevel requirements can be established and agreed by regional countries. International organizations such as the International Atomic Energy Agency (IAEA) are producing common technical standards and guides on nuclear safety; however, the regional countries can cooperate to further develop them in order to fit into the regional situations. Lower level requirements, e.g. specific safety requirements and regulatory procedures, may be different between countries due to the national specific situations. The development of those requirements is the responsibility of individual countries. However, regional cooperation is necessary to share information on regulatory priorities, good regulatory practices and procedures, etc. For some specific topics, regional countries can cooperate to develop common codes and/or standards based on sound technical knowledge. In addition to the countries with NPPs, some Asian countries are introducing or considering NPPs in their energy supply systems. To establish an appropriate regulation system, the countries with experience and technology should help the less developed countries to establish the legal basis, to develop regulations and guides for licensing and inspection, to develop an effective regulatory body, and to train regulatory staff, etc. Cooperative Safety Research 56

3 Continued nuclear safety research is necessary to ensure the safety of currently operating and aging plants, to provide the scientific-technical basis for the development of advanced safety concepts, and to support regulatory effectiveness. International cooperation has long been a significant feature in nuclear safety research. Asian/Pacific countries have also been conducting cooperative research on various safety issues in national or institutional levels. Considering the declining trend in resources for nuclear safety research, regional cooperation should be further strengthened in the future to share information, experience, and human and manpower resources. Main issues in safety research would be different from country to country. For example, countries with relatively new reactors or plans of introducing NPPs would not be much interested in the aging problem; however, it is one of the most important topic in Japan and Korea that hope to extend the operating lifetimes of their NPPs over the original design life. In 1996, the NEA Committee on the Safety of Nuclear Installations (CSNI) identified a number of safety research areas in which further work was needed: 1. aspect of steam generator and pressure vessel integrity 2. component aging 3. human factors 4. computer-based control and safety systems 5. validation of fire simulation codes and active fire protection measures 6. extended applications of thermal-hydraulic codes 7. fuel damage limits at high fuel burnup 8. further development of probabilistic safety analysis (PSA) tools 9. fission product release in relation to containment leaktightness 10. better understanding of steam explosions 11. development of models and a database on core debris coolability 12. hydrogen combustion and mitigation techniques 13. effects of aging on containment integrity In addition to the above subjects, the safe management of radioactive wastes and spent fuels would require further research. It is thought that many of the above topics deserves regional cooperation in bilateral or multilateral basis. Regional cooperation in nuclear safety research can be pursued mainly in the following ways: 1. cooperative development and assessment of computer codes 2. cooperative utilization of experimental facilities exchange of experimental data and manpower Safety Review and Inspection Achieving the high level of safety in all the regional countries is crucial for continuous development and utilization of nuclear energy. It can be facilitated by the regional cooperation in safety review and inspection of nuclear facilities. 57

4 Major safety issues can be identified and resolved through regional cooperation, considering international, regional, and national situations. The sharing of experience and expertise of individual countries through the exchange of information and manpower can provide an important feedback for the enhancement of nuclear safety in the region. In many cases, the results of cooperative safety review and inspection would be more reliable and help to improve public acceptance if regional cooperation is effectively done. Safety Information and Public Acceptance Providing reliable safety information to the public and media is crucial for future development and utilization of nuclear energy. The main issues here are what information to provide and how to communicate effectively. For effective communication with the public and media, the nuclear safety information should be well organized and distributed in effective ways. In many cases, there are differences in major concerns on nuclear safety between experts and the public. Even in the case that the questions raised by the public are not important with respect to risk, experts in nuclear safety should answer to them in convincing ways using plain words. The use of exact information is important in any cases. A reliable and systematic data base on nuclear safety can be established by the cooperation of regional countries. The information can be effectively provided to the public and concerned groups through the Internet and . In some cases, safety experts in regional countries should cooperate in making answers to various safety issues raised by anti-nuclear groups. If the media and the public once acknowledge the information provided by the expert group to be accurate, reliable and easily understandable, it would greatly improve the public acceptance. It is important to share experiences and practices between regional countries in communicating with the public effectively. Environmental Assessment and Emergency Cooperation Regional cooperation would also be effective in the area of environmental assessment and emergency planning. Regional countries can exchange the data of their NPPs and weather, and perform cooperative environmental radiation monitoring for atmospheres, seas, etc. Emergency response systems in regional countries can be interconnected and emergency drill can be conducted regionally, if necessary. Implementation of Cooperation Nuclear safety cooperation in the Asia/Pacific region can be pursued in many ways. One of the most convenient ways is to hold regional nuclear safety conferences. It has been actively implemented already; this Nuclear Energy Symposium could be a typical example. There has been International Topical Meeting on Nuclear Thermal Hydraulics, Operations and Safety (NUTHOS), Pacific Basin Nuclear Conferences (PBNC), Nuclear Safety Conferences in Asia, which can deal with the nuclear 58

5 safety cooperation in the region. Smaller workshops or symposiums, such as the Korea-Japan Symposium on Nuclear Thermal Hydraulics and Safety (NTHAS), would also help to promote mutual cooperation. It is found, however, that existing conferences are not very effective in stimulating regional safety cooperation. It would be necessary to adjust existing conferences or set up a new one for more effective contribution to nuclear safety cooperation. If several countries agree, a regional nuclear safety cooperation center may be established to coordinate regional nuclear safety cooperative activities in collaboration with national safety authorities. The office can be located in a country, and a minimum number of delegates from individual countries would work together. The cooperation center should focus on the subjects of common interests to the regional countries and cooperate with international organizations such the IAEA, OECD/NEA, WANO, etc. Korea has been proposing the establishment of the "Asia Nuclear Safety Consultation Organization (ANSCO)" which will serve as a venue for facilitating regional cooperation in the field of nuclear safety. In addition to the regional safety cooperation in the national level, cooperation in the institutional and/or private level should be strengthened, as it can be more effective in many cases. Regional cooperation can be implemented through the maximized use of telecommunication and computer systems, such as the Internet. Joint research programs and man-power exchange would be the traditional but most effective ways of cooperation. Advanced countries should also provide effective training programs for technical and management staff from less developed countries. Conclusion Regional nuclear safety cooperation between Asian/Pacific countries is vital considering the active nuclear power programs, geological proximity, large population and high population density. Five major areas of cooperation are discussed: harmonization of code and standards, safety research, safety review and inspection, safety information and public acceptance, and finally environmental assessment and emergency cooperation. Cooperative safety research can be further expanded in many areas through development and assessment of safety analysis codes, utilization of experimental facility, and exchange of experimental data and manpower. Cooperation in the safety review and inspection would help to solve important safety issues and facilitate feedback of operating experience. Establishment of a common data base and distribution system (through the Internet) on nuclear safety information would significantly improve public acceptance in the region. Finally, the cooperation between regional countries with respect to environmental assessment and emergency cooperation is inevitable considering the regional proximity and high population density. Nuclear safety cooperation has already been conducted on many subjects in bilateral or multilateral ways. However, considering the increasing number of NPPs, decreasing resources for nuclear safety, and worsening public acceptance, the coopera- 59

6 tion should be pursued in more systematic and effective ways. This would reduce the burden of countries with NPPs and help new countries introduce NPPs easily and safely. Cooperation should be pursued not only in the national level but also in institutional or private levels. Finally, it should be emphasized that exchange of manpower is one of the most effective way in harmonizing the safety goals, principles and technology. 60