Study for development of the methodology for multi-scale hydrogeological modeling taking into account hydraulic heterogeneity caused by fracture network

Saegusa, Hiromitsu; Onoe, Hironori ; Ishibashi, Masayuki; Tanaka, Tatsuya*; Abumi, Kensho*; Hashimoto, Shuji*; Bruines, P.*

It is important to evaluate groundwater flow characteristics on several spatial scales for assessment of long-term safety on geological disposal of high-level radioactive wastes. An estimation of hydraulic heterogeneity caused by fracture network is significant for evaluation of the groundwater flow characteristics in the region of tens of meters square. Heterogeneity of equivalent hydraulic properties is needed to estimate for evaluation of the groundwater flow characteristics in the region of several km square. In order to develop the methodology for multi-scale hydrogeological modeling taking into account the hydraulic heterogeneity, spatial distribution of fractures and their hydraulic properties have been modeled using discrete fracture network (DFN) model. Then, hydrogeological continuum model taking into account the hydraulic heterogeneity has been estimated based on the DFN model. Through this study, the methodology for multi-scale hydrogeological modeling according to type of investigation data has been proposed.