Simulating Radionuclide Decay Transport of Low-level Radioactive Waste with Tunnel Disposal in Nearshore Environments

• Main Authors: Chin-Chang Lu, 呂金璋
• Other Authors: Ming-Hsu Li
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/25435216718854010364

碩士 === 國立中央大學 === 水文與海洋科學研究所 === 105 === Tunnel disposal at nearshore was tentatively selected as one of final disposal sites for low-level wastes in Taiwan. The potential disposal facilities was located at 50m~200m below ground surface and designed with several disposal tunnels. The safety function of disposal tunnels with multiple engineered barriers and host rock is to provide retardation and containment of radionuclide for preventing potential release of radionuclides from the repository into human living environment to threaten human health. Simulations of flow and radionuclide transport were sequentially performed for near-field and far-field setups as proposed in technical reports of SKB SR-PSU site. In this study, three levels of grids were designed with far-field, near-filed (all tunnels), and near-field (selected tunnel section) to reduce computation time without compromising spatial resolution. The HYDROGEOCHEM_5.6 model was used to perform each level of simulations. The linkages between different simulation levels were connected by boundary conditions retrieved from outputs of other simulation levels.. Total radioactive activities of source term were estimated as given in the report of Taiwan Power Company. Steady transport, transient transport, and 11 radionuclide decay chains were performed with steady flow for demonstrations.