Records of physicochemical parameters by geochemical monitoring system in the Horonobe Underground Research Laboratory (FY2020)

Dei, Shuntaro  ; Mochizuki, Akihito  

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. In the Horonobe underground research project for FY 2020 and subsequent years, the pressure and water quality of groundwater have been continuously monitored using monitoring systems in order to obtain the data necessary for conducting the remaining important issues which were deduced from summarization of important issues between 2015-2019. This report presents pressure and physicochemical parameters (temperature, pH, electrical conductivity, oxidation-reduction potential and dissolved oxygen concentration) of groundwater which have been obtained from April 2020 to the end of March 2021 by the monitoring systems installed at the 140 m, 250 m and 350 m gallery.