It has been clarified by the existing investigated results that the underground water was existent as the vein-stream in and around the landslide area. Therefore, it was very difficult to obtain the informations concerned with location of the vein-stream of underground water by using various kinds of tracer methods. As it would be preferable to assume the location of the vein-stream before earring out the existing tracer methods and conduct the survey, the author tried the underground

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... e survey which had been utilized at the hot-spring in order to presume the location of the undetglound water vein-stream. Excellent results were obtained by this survey method.