Carbonated water injection experiment in Horonobe underground research laboratory

Kamata, Kento*; Nara, Yoshitaka*; Kashiwaya, Koki*; Tada, Yohei*; Fujii, Hirokazu*; Zhao, Y.*; Matsui, Hiroya ; Ozaki, Yusuke  

We conducted a carbonated water injection experiment at 350m stage in Horonobe URL. Two boreholes with 1m were drilled from drift wall and carbonated water was injected. The cement material powder was added one of the boreholes. The hydraulic conductivity around the borehole where only carbonated water was injected slightly decreased. The hydraulic conductivity around the borehole where both cement material powder and carbonated water decreased and increased because of the clogging of fracture by the powder and dissipation of it.