Recently, officials of MEE/NNSA answered the questions to reporters about the progress in Taishan nuclear power project.
Question: How is the latest advance in Taishan nuclear power project?
Answer: On 9 January 2018, Chinese President Xi Jinping and French President Macqueron jointly unveiled the Taishan NPP, witnessing the world’s first technology transfer project of the advanced European Pressurized Reactor (EPR). MEE/NNSA conscientiously implemented the outcome of the meeting between the two Presidents through carrying out the rigorous safety review and regulatory oversight. On 10 April, Liu Hua, Director of the National Nuclear Safety Administration, issued The 1st Fueling Approval Letter to the Taishan Nuclear Power Joint Venture Co., Ltd at Taishan Nuclear Plant Unit 1. On 16 April, Taishan Nuclear Power Plant Unit 1 completed its first reactor fueling and began operation. CCTV, Xinhua News Agency, and China Environment News reported these two events.
On 22-25 May 2018, NNSA dispatched a team of inspectors to Taishan NPP Unit 1 to inspect the preparatory work before initial criticality. The team affirmed following situations: the quality assurance system in the commissioning phase prior to the initial criticality was running normally; the nuclear safety-related activities were in the controllable conditions; the commissioning activities and periodical test program after initial fueling proceeded as planned; the requirements for corrective actions were implemented; the preparatory work prior to initial criticality met the related requirements. Meanwhile, the recommendations were further raised for the tasks to be completed and some deficiency needed to be improved before the initial criticality. Taishan nuclear company took serious corrective actions about the recommendations. With the confirmation of the NNSA headquarter and SCNROS, the criticality control point was released after the corrective actions have been completed. The Taishan NPP Unit 1 reached initial criticality on 6 June 2018.
At present, Unit 1 is at low power trial platform and is planned to connect to the external electrical grid. It will achieve full power operation in the third quarter in this year.
Question: How did NNSA carry out regulatory oversight over Taishan project? What are the conclusions?
Answer: NNSA exercises the independent regulatory control on the civil nuclear facility safety under Nuclear Safety Law of People's Republic of China and Regulations of the People's Republic of China on the Safety Supervision and Administration of Civil Nuclear Facilities. NNSA has been implementing the most rigorous safety review and oversight over Taishan EPR project and other new nuclear power technology projects. Since 2013, under NNSA’s effort, a total of more than 400 person years of review and evaluation forces in wide varieties of professionals was organized to carry out review and evaluation of 13 technology documents including Final Safety Analysis Report of Taishan Units 1 and 2, and 4 consulting meetings of expert panel on nuclear safety and environmental aspects were held. NNSA headquarter and SCNROS made a site-specific oversight inspection of earthwork, installation and commissioning activities at Taishan site, which enhanced the process control, and they invited the representatives from the nuclear safety regulatory bodies of France, Finland and the UK as well as from OECD/NEA to carry out the witness supervision of the first reactor test. In the trail operation phase after the first reactor fueling, NNSA set several control points such as first criticality, rising from low power platform and 60% power platform. For each set point, only after undergoing rigorous examination and taking corrective actions according to discovered problems, can a NPP operator enter next phase of work.
According to Nuclear Safety Law of the People's Republic of China and Government Information disclosure regulations of the People's Republic of China, we have made the review information and scrutinized reports available on our official website to the public. The Notes on Issuing “The Comprehensive Inspection Report of Nuclear Safety Before First Fueling at Taishan Unit 1”, The Approval Letter on the Environmental Impact Statement (in operation phase) of Taishan Units 1 and 2, The Notification on issuing “The 1st Fueling Approval Letter for Taishan Unit 1”, The Notification on releasing the First-criticality Control Points at Taishan Unit 1, and the relevant information on Taishan Unit 1 fueling and criticality were all released to the public through many domestic media and Wechat public account. International media such as Agence France Press and World Nuclear News reported the relevant information on 7 June 2018.
As indicated in nuclear safety review and regulatory inspection, Taishan Unit 1 was designed with full-range of engineering features dealing with varieties of accidental conditions. These are capable of preventing nuclear accidents from occurrence due to technological causes, human factors and natural disasters and help minimize the accidental consequences. It can eliminate the potentials of releasing large amounts of radioactive materials to the environment by design. Construction, installation and commissioning of the project proceed in an orderly manner, and the discovered problems were addressed in timely manner, which can bring the safety conditions under control and achieve the designed safety goals.
Question: How to solve the problems of standard-exceeding carbon content and cracks of deaerator component?
Answer: In order to deal with the problem of standard-exceeding carbon content associated with the reactor pressure vessel head, NNSA maintains the close tie with Autorité de s?reté nucléaire (ASN) through multilateral and bilateral international cooperation channels. The operator of the Taishan NPP was urged to conduct troubleshooting by using the same test, analysis and evaluation method. The ASN issued the conclusions of FA3 project on its official website in October 2017. In December 2017, NNSA submitted the treatment plan and conclusions to the expert panel of nuclear safety and environment. The consistent conclusions that the both sides have drawn are that the problem of standard-exceeding carbon content has no effect on the operation of reactor pressure vessel and it can be used; however, the in-service inspection during operation is still required. Because the effective in-service inspection methodology is still under development, the currently available reactor pressure vessel head can only serve 7 years until the methodology is successfully developed. NNSA issued the license for first fueling to the Taishan project, permitting that the vessel head serves through April 2025. If an effective in-service inspection method has not yet been developed successfully as of expiration date approved, the current vessel head must be renewed.
Cold rinse on conventional island at Taishan Unit 1 indicated that the internal supporting plate of deaerator was found to have local cracks. It has been repaired by the end of 2017, with qualified results achieved. Deaerator is a generic device used in thermodynamic system of conventional island to help remove oxygen in water supply system. This is not a nuclear safety-related system and is also used in coal-fired power plant. The welding seam with cracks on supporting plate is also non-pressure welding seam, and this issue is closed after a successful repair.
Question: How to think about the work in next step?
Answer: Taishan nuclear power project is a model of cooperation between China and France. It embodies the results of domestic and foreign contractors involved in this project through association between strong enterprises, complementary advantages, as well as division and cooperation. The project has been put into operation successfully, which benefits from the accumulated experience in sustainable development of nuclear power in China over the last 30 years and demonstrates the ability of unit construction and safety regulatory of 3rd generation nuclear power units. Under Nuclear Safety Law of the People's Republic of China, NNSA will continue to implement regulatory control, to enhance process supervision and safety scrutiny, which ensures safety-related technological problems to be dealt with effectively and makes the information about safety licensing and oversight report available to the public. We hope the public could understand correctly about the issues provided in our public information. Regarding the issues and requirements raised by the public, we will urge the contractors involved to put their corrective measures in place, which will ensure the meet of relevant regulations and standards, and will guarantee the construction of nuclear power project to be in controllable conditions and in safe operation.
