Present status of R and D for radioactive waste disposal and expectations for civil engineering in advances of their technology in Japan

About high-level radioactive waste disposal, the general invitation in a voluntary approach for selection of ''preliminary investigation areas'' which is the 1 st step of the stepwise site selection by Nuclear Waste Management Organization of Japan is started. On the other hand, about low-level radioactive waste disposal, several kinds of investigation for the burial disposal approach of the underground tunnel facility system in about 50-100 m depth below ground surface have been performed for disposing of high βγ radioactive wastes. For carrying forward each disposal project of these radioactive wastes, the integration of the state-of-the-art technology in an interdisciplinary broad research field is indispensable. Especially the role that civil engineering can play in fields, such as investigation, design, development of new materials and performance assessment for underground disposal facility is very large. In this paper, the role and expectation of civil engineering, and the latest trend in the disposal techniques to need an argument to the order of very-long term of longer than 1,000 to 10,000 years which civil engineering have not experienced until now, are described. (author)