Abstract
In Japan, the high-level radioactive wastes are in principle expected to dispose into the deep rock formations. So, it is very important to evaluate the groundwater flow in deep rocks, which is a main pathway of radionuclides released from the disposal facility. Especially, the target depth of geological disposal is basically considered about from several 100m to one 1000m below ground-surface and the crystalline or sedimentary rock is the most candidate geological formation in Japan.
Therefore, it is most important to evaluate appropriately the characteristics of hydraulic parameters, groundwater flow and so on inmore complicated geological conditions, and it is necessary to establish a systematic technique to investigate or analyze the groundwater and it's flow behavior in deep geological formations with fracture, fault and so on.
In this paper, the present status of techniques developed by CRIEPI for the investigation of hydraulic characteristics, the analysis methods of groundwater flow in fractured rocks, the investigation methods to evaluate the regional groundwater flow movement by using natural environmental isotopes or the direction and velocity of local groundwater flow by groundwater flow meter and so on, are summarized.
