Experience Review on Dismantling Procedure for American Decommissioned NPPs

Abstract

According to IAEA, the number of shutdown NPPs is totally 150 globally. In Korea, there are 23 operating NPPs and 5 NPPs under construction. But Korea has no shutdown NPP and has no experience on decommissioning commercial reactor so far except for decommissioning research reactor, TRIGA MARK-3. Based on the NPP lifetime as a 45 years, it is expected that 440 NPPs in the world and 16 NPPs in Korea will come to an end of their lifetime until 2060. In this study, decontamination and decommissioning (D and D) procedure of shutdown NPPs in US concentrated on dismantling of reactor vessel and its internals is investigated. Detailed activation analysis on primary system should be followed for safe D and D activities. However many US decommissioning projects encountered that collection and removal of irradiated small and scattered debris from segmentation were challenging issues. That's why cutting enclosure was implemented to restrict the spread of debris to other area of refueling cavity. Furthermore lifting of total weight (apx. 1,000,000 kg) on primary system including RPV, RVI and interior low-density concrete was extremely heavy.