Výzkumné centrum: Pokročilé sanační technologie a procesy

Study of physical and chemical processes in components of the deep geological repository (DGR) for high-level waste (HLW) and spent nuclear fuel (SNF) is a necessary step in final decision for disposal of radioactive material – one of the challenges for current society. Currently our work mostly concerns numerical simulations of the processes which influence the expected function of the repository to isolate the radionuclides from the environment (biosphere) for several hundreds thousands years.

The studies are typically divided to near-field (engineered barrier) and far-field (geological barrier), and there is important interface between both of them is so called excavation-damaged zone (EDZ) of the host rock. In the Czech Republic, the Radioactive Waste Repository Authority (RAWRA - SURAO) is responsible for the design and construction the repository and coordination of the needed R&D activity, including the direct financial support.

For the simulations we also develop our own codes besides the standard software. We cooperate with several institutes in the Czech Republic and also we participate or prepare participation in international projects.

Currently we specialize on the following problems (links to abstracts and examples of results):

• modelling of flow and transport processes in fractured rock – development and tests of finite-element code based on a multidimensional (porous-fracture) concept
• simulations of in-situ borehole hydraulic tests in granite massifs (Potucky and Melechov sites, projects of Czech Geological Survey)
• thermomechanical simulations with parallel computer codes (in cooperation with Institute of Geonics)
• bentonite coupled heat and moisture transport (code developments and simulation of laboratory experiments)

The list of both finished and running projects and contracts (from newest)

• Research of near-field processes of the deep geological repository of spent nuclear fuel and high-level waste, contract of Czech Radioactive Waste Repository Authority (RAWRA) for consortium of TUL/ARTEC, Czech Technical University, Institute of Chemical Technology, lead by Nuclear Research Institute Řež (2005-2008)
• Research of far-field processes of the deep geological repository of spent nuclear fuel and high-level waste, contract of Czech Radioactive Waste Repository Authority (RAWRA) for consortium of TUL/ARTEC, Nuclear Research Institute Řež, and SG Geotechnika, lead by Czech Geological Survey (2007-2009)
• Task Force on Engineered Barrier System (EBS) – project coordinated by SKB, participation by means of contract of RAWRA (2005-2008)
• Geological and other work on the test site Melechov (granitic massif), part Mathematical modelling of fluid flow in fractured media of a test site, contract of RAWRA, subcontract from Czech geological survey
• SB/660/2/03, Development of a method of in situ identification and mathematical modelling of flow and geochemical interaction in fractured matrix of compact rocks, Ministry of Environment 2003-2005
• DECOVALEX-2011 (DEvelopment of COupled models and their VALidation against Experiments), international project coordinated by SKB (2008-2011)

Publications

• O. Severýn, M. Hokr, J. Královcová, J. Maryška, Modeling of groundwater flow and contaminant transport in hard rock using multidimensional FEM/FVM, GeoProc2006 Advances on Coupled Thermo-Hydro-Mechanical-Chemical Processes in Geosystems and Engineering, HoHai University, Nanjing, China, 2006, pp. 356-363.
• Maryška J., Severýn O., Vohralík M., Numerical simulation of fracture flow with a mixed-hybrid FEM stochastic discrete fracture network model, Comput. Geosci. 8 (2004), 217-234.
• Maryška J., Severýn O., Rukavičková L.: Data management and data-mining for numerical modelling in the complex hydrogeological projects. VIIth IAHS Scientific Assembly, Foz do Iguacu, 2005.
• Maryška J., Severýn O., Rukavičková L.: Hydrogeological processes in a compact rock massif - a New Approach to the Numerical Modelling. Eurock 2005 (P. Konečný ed.), Leiden, 2005.
• M. Hokr and J. Havlíček: Comparison of multidimensional and dual-porosity models of solute transport in fractured rock, Proceedings of SIMONA 2006, Technical university of Liberec, pp. 54-61
• D. Frydrych and M. Hokr: Modelling of coupled thermo-hydraulic processes in bentonite heating experiment, Proceedings of SIMONA 2006, TU v Liberci, 46-53
• M. Hokr and J. Novák, Thermal simulations of high-level waste repository, Proceeding of ECMS, Liberec, 2007