Proposal for the spent nuclear fuel management plan from the decommissioning of Kori site NPPs

Highlights: • The management strategy of spent nuclear fuels from the decommissioning of Kori site is proposed. • Several possible options were considered and schedules were established accordingly. • The amount of spent fuel generated was examined and presented the required capacity for on-site dry storage facility. - Abstract: Kori Unit 1, the oldest commercial nuclear power plant in Korea, was permanently shut down in June 2017, and decommissioning activities will be actively conducted five years later. One of the toughest challenges in decommissioning is the removal of spent fuel from the pool, which is also the first task to be resolved before NPP decommissioning. There are a total of 6 reactors in the Kori site, and the design life of Kori Unit 2, 3, and 4 will expire in 2023, 2024, and 2025, respectively. In addition, up to now, the measures for storing spent fuel in the Kori site have been extended by the use of dense racks or the use of transshipment between nearby nuclear power plants. However, the capacity of the spent fuel pool at the Kori site is expected to be saturated in 2024, and according to the plan for the establishment of the spent fuel interim storage facility, it is expected that the facility will be operational after 2035. Therefore, an effective spent fuel management plan should be established in order to timely carry out the nuclear power plant decommissioning. The purpose of this study is to propose a management plan of spent nuclear fuels considering not only the Kori Unit 1 but also the whole site including the Kori Unit 2, 3, 4 which will be permanently shut down in the near future. We reviewed the decommissioning cases in the United States and developed a spent fuel management plan applicable to the Kori site for decommissioning. As a possible option for each nuclear power plant, scenarios for constructing a dry storage facility or an independent spent fuel pool island were applied and schedules were established accordingly. Based on this concept, we analyzed the major cost elements required for each option and applied each cost to the scenario, which suggested the most economical scenario. In addition to the economic aspect, we have taken other factors such as the government's high-level waste management policy, site conditions, decommissioning schedule, etc. into a rational fuel management plan for the Kori site. For optimal scenarios, the amount of spent fuel generated at the Kori site was examined and presented for the capacity required for the construction of a dry independent spent fuel storage installation.