SAFETY STUDY ON KOREAN DEEP GEOLOGICAL REPOSITORY FOR HIGH-LEVEL RADIOACTIVE WASTE: (1) PROCEDURES FOR CONDUCTING RISK ASSESSMENT

In Korea, a safety case development study of deep geological repository for high-level radioactive waste is being conducted, and the safety case includes safety assessment of repository as a component. In the field of disposal, the safety assessment is performed through a kind of evaluation method called a scenario in consideration of waste’s characteristics. Meanwhile, the general guidelines provided by the International Atomic Energy Agency or top-tier regulatory requirements addressed by each country do not mention detailed methods of ‘how to develop framework of safety assessment and scenarios by combining features, events, and processes’. In Korea, unlike the regulatory requirements of existing low and intermediate-level waste repository, the standards of main safety indicator based on risk for events, so it is necessary to differentiate the methodology. Based on these backgrounds, this paper suggests the detailed requirements for the safety assessment methodology of deep geological repository for high-level radioactive waste, and presents an example systematic framework reflecting these ideas. It is expected that this study will help to understand the safety assessment of deep geological repository for high-level radioactive waste from the perspective of features, events, and processes and scenario.