Method of processing concrete structures in reactors

Purpose: To handle contaminated concretes as radioactive wastes by previously stripping them and handle the remaining portion as usual structures upon processing concrete structures in desmantling the reactor. Method: The surface of the structures is scanned by using a Geiger-Muller tube or the like to investigate the state and the depth of the contamination. Then, depending on the degree of contamination or the thickness of the material to be stripped in the investigated structures, flames are sprayed for a predetermined of time to weaken the surface layer of the concretes. Then, the contaminated portions are stripped off by hammering with a vibration tool. In this way, the remaining portions can be handled as the usual structures to facilitate the entire procession. (Kamimura, M.)