Change of hydrochemical environment and relating process associated with underground microbial activities

Watanabe, Yusuke  ; Fukuda, Kenji; Murakami, Hiroaki  ; Iwatsuki, Teruki  ; Suzuki, Yohei*

Oxic condition may spread into the deep groundwater by penetrating of shallow oxic groundwater during construction and operation of geological repository for the geological disposal of nuclear waste. On the other hand, microbial activities living in deep underground such as sulfate reducing bacteria could keep the redox condition in groundwater reductive by the reduction of sulfate ion to hydrogen sulfide. In this study, in situ incubation experiment for sulfate reducing bacteria was conducted to observe its redox buffering capacity. Results showed that reducing condition was made by activities of sulfate reducing bacteria in the groundwater.