Development of a realistic radionuclide migration model for system evolution of the geological disposal repository for TRU waste

Koike, Ayaka*; Ishida, Keisuke*; Mihara, Morihiro  

To increase the confidence of the safety of the deep geological repository (DGR), NUMO has been developing a realistic radionuclide migration model for TRU (Trans-uranium) wastes produced from reprocessing process of spent fuel. In generic safety case "The NUMO Pre-siting SDM-based Safety Case"(NUMO-SC), cementitious materials inside the structural framework in the disposal tunnel were conservatively simplified due to uncertainty of its state evolution. In this study, NUMO increased confidence in reactive transport simulation used in NUMO-SC to assess the evolution and particle tracking simulation with a 3D model which precisely represents the design inside the structural framework.