A Modeling and numerical simulation for evaluating groundwater flow at the Horonobe coastal area (Contract research)

Maekawa, Keisuke  ; Saegusa, Hiromitsu; Inaba, Kaoru*; Shimogochi, Takafumi*

In the design and safety assessment of the geological disposal system of the high-level radioactive waste (HLW), it is extremely important to improve the reliability of the evaluation of the investigation of the geological environment, which provides technical basis. Especially, the knowhow and the experience of groundwater flow modeling based on the data acquired in deep underground at the coastal area are needed to be enhanced because these are little. Against this background, we have carried out modeling and groundwater flow simulation of the Horonobe coastal area. The knowledge and the knowhow acquired through this work were accumulated and arranged as a knowledge base by executing the following items. (1)The discussion of applicability of the workflow of evaluation of the groundwater flow for the coast region, and extension and update according to need. (2)Understand of groundwater flow based on existing investigation result in Horonobe coastal area, (2-1)Estimation of distribution of salinity in groundwater, (2-2)Extraction and arrangement of knowhow and judgment basis in modeling and simulation works. As a result, the knowledge was expanded concerning the groundwater flow evaluation methodology needed in design and safety assessment of the geological disposal system that is able to correspond to various geological environments in our country.