Data of long term hydro-pressure monitoring on Mizunami Underground Research Laboratory project for fiscal year 2012

Japan Atomic Energy Agency (JAEA) has been conducting Mizunami Underground Research Laboratory (MIU) Project, which is a broad scientific study of the deep geological environment as a basis of research and development for geological disposal of high-level radioactive waste, in order to establish comprehensive techniques for the investigation, analysis and assessment of the deep geological environment in crystalline rock. The MIU Project has three overlapping phases: Surface-based Investigation phase (Phase I), Construction phase (Phase II), and Operation phase (Phase III), with a total duration of over 20 years. The main goals of the MIU Project from Phase I through to Phase III are: to establish techniques for investigation, analysis and assessment of the deep geological environment, and to develop a range of engineering for deep underground application. Currently, the project is being carried out under the Phase II and III. One of the Phase II goals is set to develop and revise models of the geological environment using the investigation results obtained during excavation, and to determine and assess the changes in the geological environment in response to excavation. The long term hydro-pressure monitoring has been continued to achieve the Phase II goals. This report describes the results of the long term hydro-pressure monitoring from April 2012 to March 2013. A CD-ROM is attached as an appendix. (J.P.N.)