THE HYDROGEOLOGY OF GRANITIC-ROCKS IN DEEP BOREHOLES USED FOR COMPRESSED-AIR STORAGE

The compressed air energy storage(CAES) is a much-awaited new system f or load leveling power supply. An economical system must be developed, preventing leakage of stored air (with pressures of more than 20 atm) using groundwater pressure surrounding an unlined cavern in hard rock . The air tightness of the rock around the cavern must be confirmed. I n this study, the hydrogeology of the test site was examined prior to field air tightness tests in the borehole. The results indicate that, when evaluating the hydrogeology of the test site related to the air t ightness of rocks, it is necessary to understand the geological struct ure and fracture characteristics of the site. This is done by means of a field survey, investigations and tests in and between the boreholes , and the examination of the distribution of permeability and pore wat er pressures.