DECOMMISSIONING IN JAPAN

The Japan Atomic Energy Research Institute (Jaeri) is developing new techniques to decommission the Japan Power Demonstration Reactor, a 12. 5MWe BWR which shut down in 1976 after 13 years of operation. The project will start this year and is due for completion in 1990. Meanwhile, the Nuclear Power Engineering Test Centre has started to test cutting techniques on pressure vessels and biological shielding. Some topics discussed are the following: the use of underwater robots in decommissioning; reactor dismantling techniques, such as arc saws capable of dealing with carbon and stainless steel pressure vessels; controlled blasting, mechanical cutting, kerosene-oxygen flame jets, and hydro-laser methods to deal with concrete biological shields; ways to deal with wastes generated by decommissioning; and decommissioning techniques tested by the Nuclear Power Engineering Test Center.