Abstract
High-level radioactive waste in Japan refers to the waste resulting from reprocessing of the spent nuclear fuel. Since radioactivity of this type of waste is high and long lasting, special attention must be given to ensure the long-term protection of man and his environment. The baseline policy of Japan with regard to treatment and disposal of high-level radioactive calls for disposal into geological formations at more than several hundred meters underground. The multi-barrier system of geological disposal is being studied as the most favorable system which conforms to multiple protection concept. This paper shows the concept of the multi-barrier system and safety assessment in Japan and other countries. The long-term performance of the geological disposal sysytem can be assured by designing and constructing an appropriate multi-barrier system.
