Pre-Conceptual Design of Korean Reference HLW Vertical Disposal System

Spent nuclear fuel from Korean nuclear power plants can be disposed in the underground repository. In this report, pre-conceptual design of Korean Reference HLW Vertical disposal System (KRS-V1) is presented. Though no site for the underground repository has been specified in Korea, but a generic site with granitic rock is considered for reference HLW repository design. Depth of the repository is assumed to be 500 meters. The repository consists of the disposal area, technical rooms and connections to the ground level in the controlled area and technical rooms and connections to the ground level in the uncontrolled area. Disposal area consists of disposal tunnels, panel tunnels and central tunnel. Panel tunnels connect disposal tunnels and the central tunnel. Central tunnel leads from controlled area to uncontrolled area and connects panel tunnels to each other. Technical rooms in the controlled area includes also four shafts: canister shaft, personnel shaft and two ventilation shafts. Technical rooms in the uncontrolled area includes correspondingly access tunnel, personnel shaft and two ventilation shafts. The repository will be excavated in seven phases. Construction of the repository will begin in 2020's when Underground Research Laboratory (URL) is constructed. Next step of the construction is taken in 2030's when first part of the repository is constructed. After this phase in 2040 all the disposal tunnels for CANDU canisters are excavated and disposal of CANDU canisters will begin. Disposal of PWR canisters will begin 2066 when all CANDU canisters are disposed. Disposal tunnels and panel tunnels will be backfilled during the operation of the repository also concurrent with the disposal of the canisters. All the canisters will be disposed in 2096 and the repository will be closed. This design report for Korean reference HLW disposal system can be used to evaluate feasibility of designed high-level waste disposal system, to formulate data for long-term safety analysis, to serve as a guide for technical studies, to develop project planning to help budget and funding calculations and as background material for discussions not only with public but also between the involved experts