Groundwater and Gas chemistry by CO₂ injection test at coal mine tunnel under the sea bottom

Abstract

The pH and groundwater chemistry are expected changing by CO₂(aq) dissolution. We organized the field CO₂ injection test into Rock mass at Ikeshima coal mine tunnel under the sea bottom S.L.-130m. For the test, 4 drilling holes, which are received holes are prepared by the 7m length to upward at the tunnel roof corner of the 5m square. Additionally, the injection hole are drilled the center of square. The pH, ORP, Fe²⁺, dD, dO, major chemistry and dC_CO2 as tracer are analyze at this injection test.