Kori and Wolsong unit 1 were permanently shutdown in 2017 and 2019, respectively. During the decommissioning of a nuclear power plant, various types and levels of decommissioning waste will be generated sporadically in many areas in a relatively short period of time, so safe management of decommissioning waste is expected to emerge as a very important issue in the future. Since Korea has no experience in decommissioning nuclear power plants, radionuclides added by abnormal routes or errors in data can be identified through the list of expected nuclides and radioactivity data during decommissioning by analyzing cases of overseas nuclear power plants decommissioning. Therefore, it is expected that safety information of nuclear power plants in the United States (i.e. all information related to safety, such as radioactive waste characteristics and accident or decommissioning information at nuclear power plants) can be utilized when decommissioning Korea nuclear power plants. Therefore, in this study, the characteristics of solid radioactive waste were analyzed by collecting solid radioactive waste data during operation and after permanent shutdown of nine PWR nuclear power plants in the United States, and the correlation between the characteristics data of solid radioactive waste was analyzed. However, in the case of Korea, only data from the United States were analyzed because there was no data for each radionuclide that were disclosed when disposing of radioactive waste in LILW repository and there was no nuclear power plant that had been decommissioned. Correlation analysis of solid radioactive waste was performed by linking radioactivity of radionuclides, volume of waste, and total radioactivity data based on decommissioning work and accident data after permanent shutdown or during operation. The correlation analysis of total radioactivity, volume, and radioactivity of each nuclide of solid radioactive waste during operation and after permanent shutdown was performed using XLSTAT, an Excel add-in software, for carrying out Mann-Kendall Test and estimating Sen’s slope. Trends during operation and after permanent shutdown were compared and the effects of specific events or tasks were analyzed. This study is expected to be utilized as basic data related to safety management of decommissioning Korea nuclear power plants in future.

• In Gyu Chang(Kyung Hee University, 1732, Deogyeong-daero, Giheung-gu, Yongin-si, Gyeonggi-do)
• Jae Hak Cheong(Kyung Hee University, 1732, Deogyeong-daero, Giheung-gu, Yongin-si, Gyeonggi-do) Corresponding author