Groundwater Flow Analysis on Local Scale -Evaluation of groundwater flow condition on Local scale and setting boundary conditions for groundwater flow analysis on Site scale model in Step0-

Oyama, Takuya ; Saegusa, Hiromitsu; Onoe, Hironori 

Japan Nuclear Cycle Development Institute has been conducting a wide range of geoscientific research in order to build a foundation for multidisciplinary studies of the deep geological environment as a basis of research and development for geological disposal of nuclear wastes. Ongoing geoscientific research programs include the Regional Hydrogeological Study (RHS) project and Mizunami Underground Research Laboratory (MIU) project in the Tono region, Gifu Prefecture. The main goal of these projects is to establish comprehensive techniques for investigation, analysis, and assessment of the deep geological environment at several spatial scales. The RHS project is a local scale study for understanding the groundwater flow system from the recharge area to the discharge area. The MIU project is a Site scale study for understanding the groundwater flow system immediately surrounding the MIU construct Site. These studies are being conducted using a multiphase, iterative approach.In this study, the groundwater flow analysis was carried out in order to evaluate of groundwater flow condition on local scale and to set boundary conditions of the Site scale model based on the data obtained on borehole investigation stage in local scale.As a result of the study, groundwater flow condition on Local scale could be evaluated, and it could be found that hydraulic characteristics of the fault normal to the major direction of groundwater flow are essential.Head distribution to set boundary conditions for groundwater flow analysis on the Site scale model could be obtained.