Collection of URL measurement data in 2006 at the Horonobe Underground Research Laboratory project

The Horonobe Underground Research Laboratory (URL) Project is being pursued by the Japan Atomic Energy Agency (JAEA) to enhance the reliability of relevant disposal technologies through investigations of the deep geological environment within the host sedimentary formations at Horonobe, northern Hokkaido. The project consists two major research area, Geoscientific Research' and 'R and D on Geological Disposal', and proceeds in three overlapping phases, 'Phase I: Surface-based investigation', 'Phase II: Construction' and 'Phase III: Operation', over a period of 20 years. The Phase I geoscientific research was carried out from March 2001 to March 2005 in parallel with design and execution scheme on URL facilities. In addition, identifying key issues that need to be addressed in the Phase II/III investigations was carried out. At the inception of the Phase II investigations, an investigation report titled 'Measurement Plan and Observational Construction Program on Shaft Excavation at the Horonobe Underground Research Laboratory Project' (hereinafter referred to as Observational Construction Program') was published. The Observational Construction Program summarizes followings lessons learnt from the Phase I investigations: measurements for safety/reasonable construction, measurements for R and D on enhancement of shaft design/construction technology, and measurements for verification of the deep geological environment estimated before shaft excavation. This report summarizes the measurements data acquired at the Ventilation Shaft (to approx. 50m depth) and the East Shaft (to approx. 40m depth) in 2006 based on the Observational Construction Program. CD-ROM and DVD-ROM are attached as an appendix. (J.P.N.)