Abstract
Coastal waste disposal sites have been built on soft ground along coastal areas. Therefore, sealing materials used in impervious seawalls need to be highly workable at waters and flexible enough to behave in accordance with ground movements and to use a non-deterioration natural materials. In this study, we have endeavor to use marine clay as sealing geomaterial. The study has confirmed that geomaterials treated by adding bentonite to marine clay keep its ability conform flexibly to conform flexibly to transformation and to be workable at waters, while satisfying a required coefficient of permeability.