International case survey and literature review of maintenance strategy for decommissioning nuclear power plant during transition period

Abstract

The Chinshan nuclear power plant in Taiwan has currently shutdown when the operating license expired in 2018. However, because the operation license of the independent spent nuclear fuel dry storage facility has not been approved yet, and the fuel storage racks of Spent Fuel Pool (SFP) has almost saturated, there is not enough space to accommodate all irradiated fuels from the reactor core during the transition period. Therefore, part of the mechanical systems, plant structures and electrical equipment of the plant still have to meet the functional requirements for maintaining the safety under the pre-decommissioning activities.In this article, we introduce the international cases of permanent shutdown but the fuel still in the reactor core, and also describe the actions of the Taiwan Power Company in response to this situation. For the providing regulatory advice, we have also proposed a framework of the maintenance strategy associated with important issues for the transition period since 2018, including a revised Aging Management Program (AMP) for keeping the safety of spent nuclear fuel. From the knowledge level and important issues related to the topic, the Phenomena Identification and Ranking Table (PIRT) is quoted to complete the understanding level of requirements during the transition period.