Records of physicochemical parameters by geochemical monitoring system in the Horonobe Underground Research Laboratory (FY2017-FY2019)

Dei, Shuntaro  ; Mochizuki, Akihito  ; Miyakawa, Kazuya   ; Sasamoto, Hiroshi   

Japan Atomic Energy Agency had been conducting "geoscientific study" and "research and development on geological disposal" in the Horonobe Underground Research Laboratory (URL) for safe geological disposal of high-level radioactive waste. Groundwater pressure, pH, and oxidation-reduction potential in the deep groundwater have been continuously monitored with monitoring systems which were developed in the Horonobe URL Project. This report presents the physicochemical parameters of groundwater which have been obtained by the monitoring systems installed at the 140 m, 250 m and 350 m gallery. The data acquired from April 2017 to the end of March 2020 was summarized along with related information such as the specifications of boreholes.