abstract
- It is necessary to evaluate the influence of colloids on radionuclide transport in geologic environments relevant to safety assessment of radioactive waste geological disposal. This report summarizes the recent researches from the viewpoint of colloids generation in radioactive waste disposal system, influence of the colloids on the radionuclide transport and transport model. The colloid of radionuclide could be originated in the waste dissolution. It could be retained in the engineered barrier system. The influence of humic and biological colloids on radionuclide migration should be estimated, thus the researches on the interaction of organic matter, microbe and radionuclide are required. Colloid generation from bentonite and cement material has been investigated, however the data are not sufficient to discuss the significance in radionuclide transport. To simulate the radionuclide migration behavior under existence of colloids, the modeling of the equilibrium among three phases (radionuclide-colloid-rock) is important.