Abstract
Physical chemistry of high level radioactive waste disposal were discussed by means of crystallography, crystal chemistry, and computer simulation method. The current status and problems were reviewed in terms of smectite, a kind of clay mineral, as the most important component of the engineering barrier system. Because of the poor crystallinity, the design and investigation of the clay minerals should be carried out using molecular simulation methods under the knowledge of chemical bonding. The molecular simulation method may be the essential approach for the design of the disposal combining with the homogenization analysis, a micro-macro mechanical treatment, and also further experimental investigations.