[en] Taking one typical general contraction project-Hainan Changjiang nuclear power project as an example, this paper introduces the mass concrete construction of nuclear island foundation of Unit 1 in its installation phase, elaborates how to conduct quality assurance and supervision for concrete production, construction, supervision and management, detects relevant weak points of quality and management in the mass concrete construction through quality assurance supervision, puts forward management requirements for the supervising organizations, accumulates useful experience on how to promote contractors to implement the contract in line with national laws, regulations and to improve the management in equipment installation, commissioning and acceptance. (authors)

[en] The design of the water intake open channel of Changjiang nuclear power plant has not taken a full consideration about the sea creature and foreign matter, also cannot defend the sea wave. On the condition of severe weather, the recirculating water treatment system is easily blocked, thus lead to the shutdown of nuclear power units. This paper analyzes the design defect of the water intake open channel, through related research and experiment, puts forward optimization plan and construction process, directs the improvement and optimization of the water intake open channel, and makes sure the safety of nuclear power plant. (author)

[en] This paper is according to 'Standard Planning of Outage', which is based on the experience of M310 units. By learning form first outages of CNNP's nuclear power plants and analyzing disadvantages in the prior operation stage of isolated island type nuclear power units, this paper presents outages' planning and optimization measures for isolated island type nuclear power units. It provides a reference to outages planning of isolated island type nuclear power units. (authors)

[en] By referring to the supervision management experience of other power plants, the nuclear safety supervision mode of daily work and overhaul, the organization, program system, qualification, training and authorization of the nuclear safety supervisor of Hainan Nuclear Power Plant is determined, which is better for the internal supervision of the nuclear safety level. (author)

[en] Due to the grid load demand, the growth and gross of the grid capacity unable to meet expectations, insufficient peak load regulation capacity, and power grid accident assessment, Hainan Nuclear Power Plant was forced to a long-term below rate-power operation to ensure the safety of both the plant and the power grid. In this paper, related key impact elements for long-term below rate-power operation, studies, results and practical applications in this regard are analyzed, and countermeasures for long-term below rate-power operation are put forward. The valuable results could be referred to for nuclear power plants operated in a similar environment. (authors)

[en] According to the feedback of Fukushima accident, the nuclear power plant needs to reinforce the important system equipment of the emergency command center to make it available in earthquake situations. Referring to the requirements of relevant national laws and regulations, Hainan Changjiang nuclear power plant has determined the important system and equipment that need to be reinforced. In the seismic design, the facilities of the emergency command center and the internal system equipment have been built and put into use, mainly by installing shock absorber and other shock absorption devices to meet the seismic requirements. The method through calculation and analysis was proved feasible. During the construction of seismic reinforcement, Hainan Changjiang nuclear power plant considered the emergency needs of operating power plants, completed the project and passed the acceptance inspection of the national nuclear safety supervision authorities on the premise of ensuring the availability of emergency command center as far as possible. This paper analyzes and summarizes the relevant practical experience for the reference of peer power plants. (authors)

[en] In order to make the emergency information collection, reporting and response decision more scientific and efficient, to improve the practicality of emergency drill, to ensure the nuclear safety, Hainan Changjiang nuclear power plant has developed the emergency auxiliary decision system, based on fully absorbing the experience feedback of Fukushima nuclear accident, and by comprehensive utilization of existing emergency system and taking compatibility and function implementation into account. The system construction meets the design requirements such as security, openness, scalability, ease of use, etc. In use of scientific reasonable hardware architecture and software arrangement, the interface problem between accident consequence assessment system, core damage appraise system and the KRS, etc. solved. The intensified use and integrated display of emergency information are achieved. Via the EAL computerized and real-time transmission of the data in the judgment logic, the auxiliary judgment of emergency state is realized. In the daily management and emergency drills, practice shows that the system can play an effective role. In addition, according to the experience of practical application, this paper also puts forward some suggestions for the system improvement in the future. (author)

[en] Since the Hainanareahas the typhoon, especially the super typhoon, it is particularly urgent to prevent events similar to the Fukushima accident. We discussed the supervision methods of post-Fukushima improvement items in the unit construction stage, normal operation stage, and accident conditions in order to further improve nuclear safety level of Hainan nuclear power plant. (author)

[en] Highlights: • ⁹⁰Sr/¹³⁷Cs ratios show that Changjiang Diluted Water can extend to 126°E in spring. • ⁹⁰Sr/¹³⁷Cs ratios in coastal waters are higher than the global fallout ratio. • The effective half-life of ⁹⁰Sr in the East China Sea is 20.0 ± 0.3 y. • Groundwater input may be a new potential source of ⁹⁰Sr surplus in coastal waters. • The cumulative fallout of ⁹⁰Sr and ¹³⁷Cs onto the ocean differs from that on land. ⁹⁰Sr is useful for tracing water mass movement in oceans. We collected a suit of seawater samples from the East China Sea (ECS) in the May 2011 to investigate the spatial and vertical distribution of ⁹⁰Sr and to understand its transportation and fate. To understand the sources and transportation of ⁹⁰Sr more clearly, published ¹³⁷Cs data from the same cruise were used to obtain the ⁹⁰Sr/¹³⁷Cs activity ratios. The results showed that ⁹⁰Sr activities were controlled by the circulation system of the ECS, with high values in coastal regions and low values in oceanic waters. The plume with a high ⁹⁰Sr/¹³⁷Cs ratio showed that in late spring, the Changjiang Diluted Water could flow southeastward and extend to 126–127° E, which is farther than the previously known value of 124° E. The high ⁹⁰Sr/¹³⁷Cs ratios (1.35 ± 0.62) and a long effective half-life of ⁹⁰Sr (20.0 ± 0.3 y) in the ECS surface water revealed that ⁹⁰Sr is surplus in comparison with ¹³⁷Cs. However, historical variations in the ⁹⁰Sr/¹³⁷Cs ratio seem to preclude the simple explanation that riverine input causes a ⁹⁰Sr surplus in the ECS. Groundwater discharge with a high ⁹⁰Sr but very low ¹³⁷Cs may be a new potential source. However, it is difficult to quantify the contribution of groundwater discharge at present, and more detailed studies are required in this regard. Additionally, we compiled ⁹⁰Sr and ¹³⁷Cs water column inventory data in the western North Pacific and found that the cumulative fallout onto the ocean was different from that on land in the 20–40° N band.

[en] On March 11, 2011, Fukushima nuclear plant happened level-7 nuclear accidents, which causes huge disaster. The accident profound influence on the global nuclear power industry and reflection, the nuclear power countries all Carry out safety self-examination and review work on the in service and under building plants. National Nuclear Safety Administration put forward improvement requirements, Hainan Changjiang nuclear power (HNPC) conscientiously implement the requirements, and explores a set of management methods. This paper summarize the methods according to the situation of HNPC nuclear safety improvement work, And propose the following working suggestion. (author)