Development of grouting technologies for geological disposal of high level waste in Japan, 7; Hydrological and chemical change of the groundwater in a pre-grouted crystalline rock after earthquakes

Matsui, Hiroya ; Mizuno, Takashi   ; Sasamoto, Hiroshi   ; Sato, Toshinori  

Japan Atomic Energy Agency has been conducted a contract study with METI (Ministry of Economy, Trade and Industry) called "The project for Grouting Technology Development" since 2008. As a part of the study, the monitoring of groundwater chemistry in a pre-grouted area has been carried out for four years after pre-grouting in Mizunami URL. Measured groundwater pressures were temporarily changed by the earthquakes with more than three of seismic intensity and it was recovered within about one year. Meanwhile, the change of the chemical compositions in groundwater by the earthquakes were not detected and it show a injected grout material was not damaged significantly.