Developing risk breakdown structure for nuclear power plant decommissioning projects in Korea focusing on radioactive concrete dismantle

Abstract

The number of nuclear power plants (NPPs) preparing for dismantling under permanent suspension owing to environmental problems or end of designed lifespan is increasing worldwide. In NPP decommissioning, structural and job risk analysis and management, considering the characteristics of radioactive contamination, are critical because they are directly related to the safety of workers. However, structural disasters and job risk factors that may present during decommissioning work are not largely addressed compared to the risk of dismantling facilities such as nuclear reactor dismantling. Furthermore, characterizing NPP decommissioning is difficult owing to the unsophisticated work breakdown structure. Thus, risk breakdown structure (RBS) for risk analysis is not systematically established because risk factors are not classified according to the specified dismantling work characteristics. Therefore, the purpose of this study is to establish an RBS reflecting the characteristics of the NPP dismantling work according to structural/job as a primary step for risk analysis and management. Each work’s risk factor is analyzed based on similarity to the construction-dismantling work, targeting the cutting work when dismantling the radioactive concrete structure, which presents the most significant risk, and derives the risk factors by matching them with structural and human damage factors. The RBS model established in this study is expected to be used as primary data for risk analysis and the safety evaluation of NPP dismantling works in the future.