Currently, the Gyeongju disposal facility is planned to be operated as a complex disposal facility with three types: cave disposal, surface disposal, and landfill disposal. Approximate method and arrangement have been decided up to the 1st, 2nd, and 3rd stage disposal facilities, but the optimal method for the arrangement of the entire complex disposal facility has not been established. When establishing the subsequent disposal facility arrangement plan, the generation prospect and disposal capacity setting plan for each level of radioactive waste was established, and the disposal capacity of the subsequent disposal facility, the disposal facility method, etc. were reviewed and reflected. Among the items for deriving an efficient management plan, KEPCO E&C is going to first derive a site arrangement plan for each disposal facility of 800,000 drums of radioactive waste, and has drawn up a plan for each scenario through collaboration with other organizations. When establishing the subsequent disposal facility arrangement plan, the generation prospect and disposal capacity setting plan for each level of radioactive waste was established, and the disposal capacity of the subsequent disposal facility, the disposal facility method, etc. were reviewed and reflected.