An underground research tunnel for the validation of high-level radioactive waste disposal concept

In order to dispose of high-level radioactive waste(HLW) safely in geological formations, it is necessary to assess the feasibility, safety, appropriateness, and stability of the disposal concept at an underground research site, which is constructed in the same geological formation as the host rock. In this study, minimum requirements and the conceptual design for an efficient construction of a small scale URL, which is named URT, were derived based on a literature review. To confirm the validity of the conceptual design for construction at KAERI, a geological survey including a seismic refraction survey, electronic resistivity survey, borehole drilling, and in situ and laboratory tests were carried out. Based on the results, it was possible to design URT effectively with a consideration of the site characterization. The construction of URT was started in May 2005 and the first stage of the construction of the access tunnel could be successfully completed in Aug. 2005