In the low-level radioactive wastes from nuclear power stations, it is necessary to reduce the volume of the wastes as far as possible, and then finish them into the solids with the properties suitable to their sea or ground disposal. In Japan, for the purpose, the methods of cement and asphalt solidifications are being employed, and further the method of plastic solidification is also studied. Developed for the practical use by JGC Corporation, the asphalt and the plastic solidification methods are described, and also in this connection, the wastes to be solidified, the properties of the solids and volume reduction are explained. At present, the places of the disposal and the standards are not established yet, therefore, the research and development on the solidification should be diversified to meet any possible circumstances. (J.P.N.). Kuribayashi,-Hiroshi (JGC Corp., Tokyo (Japan)
