Abstract
The purpose of this study was to investigate the sorption processes in both natural and engineered barriers since the multi-barrier concept has been recoginized to be the most feasible way to construct a radwaste disposal facility, where crushed rocks and mixing clay minerals were taken as buffer material and backfilled material herein. And the purpose was to establish a standard process of prepearing experimental column to avoid the personal error in column experiment. This study also dealt with the sorption mechanisms of several kinds of nuclides such as strontium-90, cesium-137, iron-55, cobalt-60, nickel-63, iodine-129, cerium-144, technetium-99, americium-241 and uranium-235 in Portland Type-I cement and local host rocks, including granite from Kinmen, basalt from Penghu, andesite from Orchid Island, and clay minerals. The experimental results show that the sorption capacities of the tested cement and host rocks are lower than those of clay minerals, where the sorption capacity is dominated by the sorption mechanism of minerals in material. It is feasible to use the weighted average approach to find the Kd for mixed clay minerials, which is satisfied with linear isotherm sorption for selected mixing ratio. The experimental results depends on the content minerals of tested media in column experiment. Hopefully, the results from this study can be helpful for obtaining parameters of radwaste disposal site in performance assessment.Keywords: radwaste, disposal, nuclides, migration