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[en] The following topics are discussed: Education concept (Educational system; Types of education and training; Education and training groups); Qualifications and competencies (Staff groups); Certifications, licences and authorisations; Educational and training facilities, training programmes; educational plans, education and training assessments, records. (P.A.)
[en] Operating license extension (OLE) is now performed to expiration the operating license in some nuclear power plants (NPPs) in China. Prior to the safety demonstration, it is obliged to identify the demonstration basis. Currently, license renewal (LR) from the US and long term operation (LTO) from IAEA are two predominant OLE strategies in the world. In this paper, current licensing basis (CLB) for LR and LTO were comparative studied, methods and concrete contents were suggested on basis of technology policy given by National Nuclear Safety Administration (NNSA), to provide the technical support on safety demonstration basis (SDB) for OLE in the future. (authors)
[en] Spent fuel disposal in Finland is in the phase where Posiva is preparing for construction of the encapsulation plant and spent fuel disposal tunnels, and later submitting the operating license application. As part of the preparations, Posiva is planning the future operating phase of the spent fuel encapsulation and final disposal facility. The original operating plan has been to dispose of fuel from both Olkiluoto and Loviisa NPPs in parallel starting around 2024. Another option is to start disposing fuel from Olkiluto NPP first, and continue with Loviisa NPP fuel later. Whatever production option is selected it requires actions and preparations at Loviisa NPP. This paper presents some of these action. (author)
[en] As nuclear power plants and large research and isotope production facilities age, licensees are applying for permission to extend the operation of such nuclear installations beyond their assumed design life. It is the current practice in such cases for the Canadian Nuclear Safety Commission (CNSC) to request the licensee to conduct an Integrated Safety Review (ISR). This is to collect sufficient and necessary information to allow CNSC staff to make determinations and recommendations to support regulatory decisions on granting a licence for safe and reliable continued operation of such facilities. The ISR (a process equivalent to a one-time Periodic Safety Review (PSR)) is a systematic and comprehensive assessment to determine the extent to which the plant conforms to modern codes, standards and practices; the licensing bases remains valid over the proposed extended operation period; arrangements are in place to maintain continued plant safety; and to ensure improvements are implemented to resolve identified issues. This paper presents the Canadian regulatory oversight experience, challenges, and lessons learned from the assessment of the results of an ISR that was conducted by a licensee to extend the operating licence of the National Research Universal (NRU) reactor in Canada. (orig.)
[en] In Brazil, according to CNEN standard, a nuclear power plant has authorization to operate for 40 years. Angra 1 commercial operation started in 1985 and it has license to operate until 2024. Eletronuclear aims to extend the operation of the Angra 1 plant from 40 to 60 years. To obtain the license renewal by more than 20 years (long-term operation), Eletronuclear will need to meet the requirements of 10 CFR Part 54, CNEN NT-CGRC-007/18 and NT-CGRC-008/18 (CNEN technical notes). To obtain a license renewal to a long-term operation it is necessary to demonstrate that the plants will operate according to safety requirements, through analysis, testing, aging management, system upgrades, as well as additional inspections. Plant operators and regulators must always ensure that plant safety is maintained and, when it is possible, strengthened during the long-term operation of the plant. One of the documents to obtain a license renewal to a long-term operation is the Quality Assurance Program (QAP). Angra 1 has a QAP according to 10CFR 50 App B and CNEN NN 1.16 for safety related items. However, according to 10 CFR50.34, NUREG-1800 Appendix A.2, NUREG-1801 Appendix A-1 of Nuclear Regulatory Commission (NRC) and NT-CGRC-007/18 and NT-CGRC-008/18 of CNEN, the QAP needs to include the items that are not safety related but are included in the Aging Management. This article will discuss the Angra 1 QAP for the license renewal to a long-term operation according the standards approved by CNEN. (author)
[en] In order to develop the system to affect more advanced and rational regulations of nuclear fuels and earlier introduction of new technologies in nuclear power plants, domestic and overseas safety regulation systems and state of their implementation for water cooled reactor fuel and safety analysis code had been investigated and new regulation system to affect nuclear fuel type authorization and analysis code certification was proposed. Topical report system for common parts related with nuclear fuel type authorization and analysis code certification was firstly proposed for knowledge base. Maintaining consistent safety examination supported by experts, introduction of domestic efficient system for lead irradiation test fuel, and analysis code certification and quality assurance were also proposed. (T. Tanaka)
[en] The Modulated Power Law Process (MPLP) is a three-parameter stochastic point process that can be used to describe the failure times of repairable systems. While the Non-Homogeneous Poisson Process (NHPP) or the Renewal Process (RP) implies that a system is exactly on the same condition just after a repair as just before a failure, the MPLP allows for the system to be affected both by failure and repair. For this reason this model is adequate for evaluating the recurrent events that incorporate both time trends and effects of past events such as the renewal type behavior. The purpose of this paper is to evaluate the MPLP as a model for the rate of occurrence of failures (ROCOF) of repairable systems to decide for an extension of qualified life in the context of a license renewal of a nuclear power plant. The analysis was carried out considering some field data spanning a 2300 calendar day period, which is approximately equivalent to four burn-up cycles and refueling periods. The reliability is estimated, and maintenance strategies are discussed, concerning the results of the case study presented. As a conclusion, the MPLP is adequate for modeling the rate of occurrence of failures that are time dependent, and can be used where aging mechanisms are present in the operation of repairable systems. This means that equipment characteristics that are important may be inserted into the model and the results can help make decisions in the context of maintenance programs, as is the case with the maintenance rule concept that has been proposed by the U.S. Nuclear Regulatory Commission and has just been implemented in nuclear power plants in Brazil, for instance. The difficulty with data acquisition for applying point processes is discussed throughout.
[en] The present work is based on the identification of a regulatory gap in the national methodologies for the evaluation of applications for life extension of the Brazilian nuclear power plants. In the nuclear context, Brazil has two nuclear units operating (Angra 1 and Angra 2) and one under construction (Angra 3). Located in the city of Angra dos Reis, in the state of Rio de Janeiro, the Central Nuclear Almirante Álvaro Alberto (CNAAA) plays an important role in the Brazilian energy program. With the sum of events taking place in the national energy scenario - increased demand, water crisis and the hydrothermal transition of the national energy matrix - it has become important to turn our eyes towards our Power Plants and consider the importance they have in Brazil's energy program. Facing the proximity to the end of the licensed period of operation of the Angra 1 Unit, it is necessary to identify, understand and generate knowledge in the Nuclear Area to provide subsidies for regulatory assessments of life extension requests for Brazilian nuclear power plants. Thus, the main purpose of this research is to identify the Regulatory Requirements for life extension applications used by the US regulatory agency and the International Atomic Energy Agency (IAEA and U.S.N.R.C) for Nuclear Plant Renewal License. Specifically, it aims at identifying and presenting the aspects considered necessary in the request, safety assessment and inspection of requests for Life Extension of Brazilian Nuclear Plants, based on international regulatory requirements, to propose a proper method applicable to our Nuclear Units. For this, methodologically, the present research invests in a bibliographical survey about the mentioned international methodologies. This methodological option focuses on the need to understand how the application process for the renewal of an operating license is carried out, as well as the identification of all necessary requirements as a fundamental process for making governmental decisions regarding the national nuclear context. (author)
[en] The in-service inspection program of the Angra 1 plant is updated every 10 years, according to applicable standards - designer (American Project - are followed NRC requirements) and CNEN. NRC approves the use of ASME Section XI (In-service Inspection of Nuclear Power Plant Components). The object of inservice inspection of components in nuclear power plants is to provide a continuing assurance that they are safe. To provide this assurance for those components that are subject to the requirements of the ASME Boiler and Pressure Vessel Code, a set of rules has been formulated to provide assurance that the functional requirements of the components are available when required. The rules have been arranged to provide appropriate levels of assurance according to the importance of the component in its relationship to plant safety. The classifications that are established during design and manufacturing have been adopted to provide the levels of importance for the components. The types of components typically found in the various classifications have then been identified and rules formulated for each type. For each type of component in each classification, the functions have been considered and methods of inspecting, testing, or monitoring each component is specified. These rules include methods of determining the limits of acceptance of the results. Should it be necessary to take corrective action to repair various components, rules have been provided to establish acceptable methods of repair or replacement. Angra 1 started the Renewal License and Long-term Operation project and there are three important Aging Management Programs (AMP) that are based on ASME section XI. This article will discuss the ASME section XI subsections that are important for the License Renewal and Long-term Operation for Angra 1. (author)
[en] Highlights: • Hazard and operability study suggests the pyroprocessing facility design strategies. • Hazards, operability issues, and off-normal situations are analyzed. • Proposed mitigation methods hinder severe accident scenarios. • Nuclear material accounting proposes implementation of a strong safeguards design. - Abstract: Pyroprocessing treats nuclear fuel using electrochemical techniques for a variety of applications, whether to process used uranium oxide fuel for back-end management, or to reprocess used metallic fuel for an advanced fuel concept. Since there are proliferation risks associated with special nuclear material (SNM) processed in a pyroprocessing facility, the high reliability safeguards (HRS) methodology has been developed to implement safeguards, safety, and physical security (3S) together with operations from a design-driven perspective. This paper suggests the design strategies by integrating a hazard and operability (HAZOP) analysis. It is a process hazard analysis, essential for identifying hazards, operability issues, severe accident scenarios, and for mitigating consequences with the corresponding protection methods. It is a preliminary step for an eventual quantitative, probabilistic risk analysis, which may be needed for obtaining an operating license for a commercial pyroprocessing facility. The focus of this HAZOP analysis was on major pyroprocessing subsystems; voloxidation, electroreduction, electrorefining, electrowinning, and the argon atmosphere control system. Deviations were analyzed from normal operating conditions, and methods were thoroughly prepared to prohibit or mitigate off-normal situations. Importantly, pressure buildup or high temperature in the systems can increase the risk of initiating fire/explosion, which may eventually release radiation to the outside. Safety relief valve installations, valve actuation and heater automatic shutdown systems, etc., would be helpful to alleviate operational problems. This enhanced HAZOP also suggests a strong safeguards design for the facility by proposing nuclear material accounting (NMA) locations for the purpose of reducing potential proliferation risks.