The underground facility is located in the village of Bukov in the Žďár nad Sázavou district, Vysočina region, Czech Republic. As with similar facilities of its type, it makes use of a pre-existing underground mine infrastructure, namely the former Rožná I uranium mine. The underground areas of the URF are located on the 12th level close to the B-1 shaft
The Bukov URF is located in crystalline rocks, i.e. in a high-strength and low-permeability environment corresponding to that of the future deep geological repository. The underground facility consists of a system of newly-excavated underground galleries constructed in differing geological conditions according to the requirements of specific planned experiments
The underground research facility concept plays an important role in terms of the overall research and development of deep geological repositories and a number of similar facilities worldwide have been in operation for many years such as the Grimsel Test Site in Switzerland and Äspö HRL in Sweden. Since as early as the 1960s, such facilities have been providing essential data concerned with gaining an understanding of rock mass processes, the testing of the robustness of so-called engineered barriers and, not least, for safety analysis purposes.
Both the data and experience obtained play an important role in the deep geological repository site selection and evaluation process and the optimisation of engineering, technological and construction techniques. The activities performed at underground facilities contribute towards the education of highly-qualified experts, significantly enhance the professional level of national disposal programmes and allow the Czech Republic to engage in valuable international cooperation.
The construction of the Bukov URF commenced in 2013 and was completed in 2017. The exploration phase included the excavation of the BZ-XIIJ access tunnel (320m long) followed by a drilling campaign aimed at verifying the geological structure and final selection of the rock blocks. The third phase consisted of the excavation of the research galleries. In order to ensure the highest possible standards for future experimentation work, the so-called smooth blasting technique was employed during the excavation of the galleries. The underground construction work consisted of the excavation of the BZ-XIIJ access tunnel, three drilling chambers, a laboratory crosscut and four experimental chambers.
The aim of the “Complex geological characterisation” project consisted of the detailed description of the rock environment of the Bukov URF so as to determine the future location of individual experiments. In addition, the unique data gathered, which can only be obtained from the opening of underground rock masses, assisted in the interpretation of the development of certain rock environment parameters with depth. The research involved the following areas of study: geological structure, geotechnical properties, hydrogeological properties, seismicity, rock transport properties and the geological and geomechanical modelling of the facility.
The experimental programme consists of a series of projects aimed at supporting both the safety assessment of potential deep repository sites and overall technical feasibility. The research programme has been divided into several sections.