The saturation of South Korea's at-reactor (AR) spent fuel storage pools has created a necessity for additional spent fuel storage capacity. Because the South Korean government has a plan to increase the number of nuclear power plants to 27 units by 2015, the increase of spent nuclear fuel generation will be accelerated. Because there is no clear national plan for spent nuclear fuel permanent disposal, the Korea Hydraulic Nuclear Power Company is planning to construct a spent fuel interim storage facility with 11,000 tHM capacity for Pressure Water Reactor (PWR). This study estimates the operation time periods of interim storage facilities with regard to the re-racking plan of spent fuel storage pools and construction of new nuclear power plants. To do this, the amount of spent fuel generation was estimated through a nuclear power supply plan until the year 2015. After 2015 year, the amount of spent fuel generation was estimated by using three scenarios that this study assumes according to variation of number of nuclear power plants: the "discontinue scenario", the "maintenance scenario", and the "increase scenario". In the case of the "increase scenario", projections of the share of nuclear power were estimated using the MESSAGE-V method. It is estimated that an interim storage facility will be needed by 2016, and for all scenarios, it is estimated that interim spent storage facilities will be saturated by 2041 with current burnup and by 2049 with extended burnup. In order to get a more meaningful result, it is recommended that a study on the practical storage facility capacity with respect to the risk assessment, public acceptance and further research should follow. (C) 2007 Elsevier Ltd. All rights reserved.