ABSTRACT
There are several concepts of radioactive waste containment: deep geological disposal in crystalline host rock formations (e.g. granite), in salt and in consolidated clay (Opalinus type) host rock formation. The safety and long-term performance of underground permanent repositories rely on a combination of several engineered and geological barriers. Clay barriers with compacted bentonite play a key role in these concepts. In the present work results of clay mineralogical and geotechnical investigations of bentonites related to nuclear waste disposal were reported. Different processes of bentonite buffer alteration and their influence on physicochemical properties of the buffer material were described.
