Studies on geological disposal of high-level waste in China

China has proposed a preliminary R and D program for the deep geological disposal of high-level waste. The development strategy for high-level waste repository includes 3 stages: siting and site characterization, underground research laboratory for a site-specific, and repository. It is expected that a national geological repository will be built and put into operation during 2030-2040. The deep geological disposal method will be used. The disposed waste will be vitrified high-level waste, transuranic waste and some spent fuel from CANDU reactors. the repository concept is shaft-tunnel-silo located in a saturated zone in granite. Because of rare inhabitants, stable crust, and a good geological and hydro-geological condition, the Beishan area, a Gobi desert in Gansu province, is considered as the most potential candidate area for China's geological repository. Bentonite is selected as a sort of backfill for the repository. With in-situ tests, a great number of deep geological data have been obtained. In laboratory, some data of the adsorption and diffusion, related with radioactive-nuclides' migration in granite and bentonite, have also been obtained; some devices have been established to simulate the temperature, pressure, and redox condition of the real repository. Studies on siting evaluation, geochemical behavior of radioactive nuclides, buffer material, and environment impact assessment have also been conducted. Some cooperations with International Atomic Energy Agency have been very successful. (authors)