Vaclava Havlova - Academia.edu (original) (raw)

Papers by Vaclava Havlova

Technetium (Tc-99, T 1/2 = 2.1·10 5 yrs) and selenium (Se-79, T 1/2 = 6.5·10 4 yrs) belong among ... more Technetium (Tc-99, T 1/2 = 2.1·10 5 yrs) and selenium (Se-79, T 1/2 = 6.5·10 4 yrs) belong among fission products, being produced by fission of nuclear fuel. Both elements can significantly contribute to risk due to their complicated chemistry, long life times, high mobility and prevailing anionic character. Therefore, knowledge of migration behaviour under different conditions can significantly improve input into performance and safety assessment models. Granite is considered as a potential host rock for deep geological disposal of radioactive waste in many countries. Granitic rocks consist usually of quartz, feldspar, plagioclase (main components), mica, chlorite, kaolinite (minor components). The main feature of the rock is advection governed transport in fractures, complemented with diffusion process from fracture towards undisturbed rock matrix. ) with granitic rock. Furthermore, the importance of mineral composition on sorption of anionic species was also studied. The batch so...

SITEX is a 24 months FP7 Euratom project (from january 2012 to december 2013) led by IRSN and bri... more SITEX is a 24 months FP7 Euratom project (from january 2012 to december 2013) led by IRSN and bringing together organisations representing technical safety organisations and nuclear safety authorities performing technical and scientific assessment of geological disposals for radioactive waste in the framework of their respective national regulatory review process of the safety case. Civil society outreach specialists of interaction with civil society are also involved in the project. SITEX aims at establishing the conditions required for developing sustainable interactions among experts from various horizons (nuclear safety authorities, technical safety organisations, civil society organisations...) capable of developing and coordinating joint and harmonized activities in relation with the safety assessement of the safety case. Among foreseen activities, partnership with the civil society experts is considered as a key function of the future network in order to contribute in enhanci...

<p>Transport and flow through fractured crystalline rocks i... more <p>Transport and flow through fractured crystalline rocks is an important and often studied topic in the context of nuclear waste disposal, given that the heterogeneity of fluid transport constraints the efficiency of radionuclide sorption processes. In past years, several studies have provided numerical simulations of the flow rate that can be expected in different types of fractures. Such studies rely on the required length-scale and spatial resolution of geometrical data in order to conduct flow and transport modeling. The numerical results are validated against tracer data of break-through experiments, such as the recently available spatiotemporal tracer concentration analysis, obtained from positron emission tomography (PET) . In many cases, however, the results obtained from the numerical simulations differ greatly from the experimental observations. While some numerical models commonly operate under the cubic law assumption, which defines a fracture as two perfectly parallel smooth surfaces, more advanced simulations include the effect of fracture surface roughness. Such results suggest the need of an improved understanding of transport heterogeneities as a function of fracture surface roughness and topography. Moreover, a systematic evaluation provides insight into the model complexity required for reliable radionuclide transport and flow predictability in potential host rocks.</p><p>In this study, we focus on the numerical modeling of flow through a fracture while taking into account surface roughness of the fracture walls, and validating the results against tomographic methods. For this purpose, the structural parametrization of the fracture is carried out by performing the segmentation of micro-computed tomography (µCT) images obtained from Granite samples from the Mrákotín quarry  in the Czech Republic. Subsequently, interferometry measurements of identical fracture material are carried out in order to quantify the details in the surface topography at the nm to µm scale. Resulting data are combined with µCT data through statistical methods, which provide a more meaningful definition of the surface topography, and are compared with numerically generated surface roughness. Resulting numerical simulations are then validated against PET measurements. As a result from the outlined workflow and the quantitative comparison, we provide suggestions of general applicability of the required degree of complexity for surface geometry segmentation in flow simulations.</p>

Energy Procedia

Abstract REPP-CO 2 is a Czech-Norwegian project representing a major step towards CO 2 storage in... more Abstract REPP-CO 2 is a Czech-Norwegian project representing a major step towards CO 2 storage in the Czech Republic. The project is an advancement towards a pilot project in geological settings with large CO 2 storage potential in the future. The presented work is focused mainly on static long-term laboratory experiments in CO 2 -rock-brine systems. Both equilibrium and kinetic geochemical modelling studies on CO 2 -rock-brine interaction were consequently carried out using geochemical program PHREEQC. The results from experiments and simulations could support the risk assessment argumentation of the storage site performance.

Energy Procedia

The genesis of the CO 2 storage resource management system (SRMS) Scott Frailey*, Illinois State ... more The genesis of the CO 2 storage resource management system (SRMS) Scott Frailey*, Illinois State Geological Survey; George Koperna, Advanced Resources International, inc; Owain Tucker, Shell Global Solutions Risk-based monitoring network design for geologic carbon sequestration sites

Wissenschaftliche Berichte Fzka, 2009

The study was focused on mobile organic matter quantification from the Ruprechtov natural analogu... more The study was focused on mobile organic matter quantification from the Ruprechtov natural analogue site (CZ) and its characterisation. Only a small fraction of sedimentary organic matter can be released into the solution: 2.8 %. The release rate is dependent on the organic matter composition and the degree of coalification. The mobile organic matter can be represented by extracted natural humic acid. The correspondence was clarified by MALDI-TOF MS spectra which showed high degree of similarity with those of organic substances from natural mobile organic matter in Ruprechtov groundwater and with those leached from the sediment in contact with solution. MALDI-TOF spectra also proved that the mobile organic matter consists of small independent molecules with molecular weight up to 1000 Da.

This is an Open-Access article distributed under the terms of the Creative Commons Attribution No... more This is an Open-Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/ by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited The article summarises the status and competence of UJV Rez, a. s. (up to 2012, the Nuclear Research Institute Rez, Czech Republic) in the field of radioactive waste (RAW) management as a company managing of 95% of institutional radioactive wastes in Czech Republic. UJV Rez a. s. has been one of the Czech Republic's key research and engineering institutions in the field of nuclear energy production since 1955. The company processes and conditions prior to storage 95% of so-called institutional RAW and is the principal partner of the state with respect to the research support of the Czech deep geological repository development project. UJV Rez a. s. boasts its own accredited radiochemical analytical test laboratory, unique of its kind in the Czech Republic. Of equal importance is UJV Rez's active participation in a range of international organisations and associations and its involvement in wide range of international projects, and so as European projects. One of them is EU funded project PREDIS: Pre-disposal management of radioactive wastes, that has started at September 2020, focused on the field of low level radioactive waste (LLW) and intermediate level radioactive waste (ILW) pre-disposal.

Journal of Radioanalytical and Nuclear Chemistry, 2013

ABSTRACT The transport of 3H+ (as HTO) and 36Cl− (as Na36Cl) was investigated in the dynamic syst... more ABSTRACT The transport of 3H+ (as HTO) and 36Cl− (as Na36Cl) was investigated in the dynamic system, i.e., in the columns filled with crushed pure granite and fracture infill of various grain sizes. The aim of column experiments was to determine important transport parameter, such as the retardation, respectively distribution coefficients, Peclet numbers and hydrodynamic dispersion coefficients. Furthermore, the research was focused to quantification of the effect of grain size on migration of studied radionuclides. The experimental breakthrough curves were fitted by a model based on the erfc-function, assuming a linear reversible equilibrium sorption/desorption isotherm, and the above mentioned transport parameters were determined. The results showed that influence of grain size on sorption of 3H+ and 36Cl− was negligible. Retardation and distribution coefficients of both tracers converged to one and zero, respectively, in case of all fractions of crushed granite and infill material. Generally, the presumed ion exclusion of 36Cl in anionic form was proved under given conditions, only very weak one seems to exist in a case of infill material. In principal, both radionuclides behaved as non-sorbing, conservative tracers. On the other hand, the influence of grain size on Peclet numbers value and on dispersion coefficient was observed for both crystalline materials, namely in agreement with theoretical suppositions that the values of Peclet numbers decrease with increasing grain size and values of dispersion coefficient increase.

International Journal of Global Energy Issues, 2014

Any geological disposal/storage facility must prove its safe performance prior to licensing, rega... more Any geological disposal/storage facility must prove its safe performance prior to licensing, regardless of whether the compound is solid radioactive waste (RW) or gaseous carbon dioxide (CO 2 ). The disposal/storage facility is considered safe if it meets the relevant safety standards and proves its reliable safe performance over defined timescales. This paper presents a crossnational comparison of the safety/risk assessment aspects of ultimate disposal facilities for RW and CO 2 in the Czech Republic, Switzerland, India, and Bulgaria, completed in an international project. In both fields, the main goal of safety assessments is to create a reliable evaluation of the disposal system performance over long timescales. The procedures are based on the following scheme: system description -system development description -model development -consequence analyses. Due to the long temporal and large

ASME 2009 12th International Conference on Environmental Remediation and Radioactive Waste Management, Volume 2, 2009

ABSTRACT Groundwater data from the natural analogue site Ruprechtov have been evaluated with spec... more ABSTRACT Groundwater data from the natural analogue site Ruprechtov have been evaluated with special emphasis on the uranium behaviour in the so-called uranium-rich clay/lignite horizon. In this horizon in-situ Eh-values in the range of −160 to −280 mV seem to be determined by the SO42−/HS− couple. Under these conditions U(IV) is expected to be the preferential redox state in solution. However, on-site measurements in groundwater from the clay/lignite horizon show only a fraction of about 20% occurring in the reduced state U(IV). Thermodynamic calculations reveal that the high CO2 partial pressure in the clay/lignite horizon can stabilise hexavalent uranium, which explains the occurrence of U(VI). The calculations also indicate that the low uranium concentrations in the range between 0.2 and 2.1μg/l are controlled by amorphous UO2 and/or the U(IV) phosphate mineral ningyoite. This confirms the findings from previous work that the uranium (IV) mineral phases are long-term stable under the reducing conditions in the clay/lignite horizon without any signatures for uranium mobilisation. It supports the current knowledge of the geological development of the site and is also another important indication for the long-term stability of the sedimentary system itself, namely of the reducing geochemical conditions in the near-surface (30m to 60 m deep) clay/lignite horizon. Further work with respect to the impact of changes in redox conditions on the uranium speciation is on the way.

Journal of Radioanalytical and Nuclear Chemistry, 2015

ABSTRACT Isotopes of caesium and selenium belong among fission products, being present in spent n... more ABSTRACT Isotopes of caesium and selenium belong among fission products, being present in spent nuclear fuel (SNF) and high level waste (HLW), and contribute significantly to the risk associated with SNF and HLW disposal in deep geological repositories. The present work is focused on sorption behaviour of Cs and Se species on two types of crystalline rock, granite from Melechov massif (Czech Republic) and Äspö diorite from the underground laboratory Äspö (Sweden). The aim was to compare sorption behaviour of Cs and Se on these rocks under aerobic and anaerobic conditions and determine the influence of redox conditions on their kinetic sorption properties.

Uranium, Mining and Hydrogeology, 2008

Natural analogue study at the Ruprechtov site (Czech Republic) was aimed to investigate and under... more Natural analogue study at the Ruprechtov site (Czech Republic) was aimed to investigate and understand the behaviour of natural radioelements in sedimentary formation. The isotopic exchange tests with 233U were used to compare the results of exchangeable uranium (Uex) determination with the results of the first steps of sequential leaching tests. Measured interaction isotherms showed a significant dependence of uranium

Fourth EAGE CO2 Geological Storage Workshop, 2014

ABSTRACT Safety of any waste storage is based on safety functions of storage system components. C... more ABSTRACT Safety of any waste storage is based on safety functions of storage system components. CO2 storage multibarrier system comprises of injection borehole casing, cement, used for infill and plug and host rock. Their performance and behaviour in both short term and long term periods has to be studied in order to evaluate changes of the materials under CO2 and underground condition influence. The anthropogenic material changes are the most important parameters for injection borehole integrity and potential CO2 leakage. The presented results demonstrate interaction of materials that should fulfill safety function in the multibarrier CO2 storage system. Steel samples, cement and host rock samples were studied under long-term interaction with spCO2. Material and their property changes were then evaluated using XRD, TEM and BET measurements.

Fourth EAGE CO2 Geological Storage Workshop, 2014

ABSTRACT Based on selection and also on availability of suitable core samples, reservoir rocks fr... more ABSTRACT Based on selection and also on availability of suitable core samples, reservoir rocks from 3 geological structures were selected for the experiments. The samples were exposed to spCO2 under 7,5 MPa and 35C for 3 month. Long term static experiment revelead that selected rock samples kept their properties regardless spCO2 exposure. Such an information would be important studying the suitability of reservoir structure for CO2 exposure as mineral changes are the most important parameter for potential injectability and storativity evaluation.

Uranium, Mining and Hydrogeology, 2008

The behaviour of acid contaminantion in fucoid sandstone was studied on samples from Straz pod Ra... more The behaviour of acid contaminantion in fucoid sandstone was studied on samples from Straz pod Ralskem, Czech Republic. Long term leaching of solid phase cores of contaminated fucoid sandstone with very low value permeability about 0.6 mD by background groundwater from Cenomanian aquifer was performed and possible chemical reactions were proposed. Results of leaching and modified extraction method divided core

Technetium (Tc-99, T 1/2 = 2.1·10 5 yrs) and selenium (Se-79, T 1/2 = 6.5·10 4 yrs) belong among ... more Technetium (Tc-99, T 1/2 = 2.1·10 5 yrs) and selenium (Se-79, T 1/2 = 6.5·10 4 yrs) belong among fission products, being produced by fission of nuclear fuel. Both elements can significantly contribute to risk due to their complicated chemistry, long life times, high mobility and prevailing anionic character. Therefore, knowledge of migration behaviour under different conditions can significantly improve input into performance and safety assessment models. Granite is considered as a potential host rock for deep geological disposal of radioactive waste in many countries. Granitic rocks consist usually of quartz, feldspar, plagioclase (main components), mica, chlorite, kaolinite (minor components). The main feature of the rock is advection governed transport in fractures, complemented with diffusion process from fracture towards undisturbed rock matrix. ) with granitic rock. Furthermore, the importance of mineral composition on sorption of anionic species was also studied. The batch so...

SITEX is a 24 months FP7 Euratom project (from january 2012 to december 2013) led by IRSN and bri... more SITEX is a 24 months FP7 Euratom project (from january 2012 to december 2013) led by IRSN and bringing together organisations representing technical safety organisations and nuclear safety authorities performing technical and scientific assessment of geological disposals for radioactive waste in the framework of their respective national regulatory review process of the safety case. Civil society outreach specialists of interaction with civil society are also involved in the project. SITEX aims at establishing the conditions required for developing sustainable interactions among experts from various horizons (nuclear safety authorities, technical safety organisations, civil society organisations...) capable of developing and coordinating joint and harmonized activities in relation with the safety assessement of the safety case. Among foreseen activities, partnership with the civil society experts is considered as a key function of the future network in order to contribute in enhanci...

<p>Transport and flow through fractured crystalline rocks i... more <p>Transport and flow through fractured crystalline rocks is an important and often studied topic in the context of nuclear waste disposal, given that the heterogeneity of fluid transport constraints the efficiency of radionuclide sorption processes. In past years, several studies have provided numerical simulations of the flow rate that can be expected in different types of fractures. Such studies rely on the required length-scale and spatial resolution of geometrical data in order to conduct flow and transport modeling. The numerical results are validated against tracer data of break-through experiments, such as the recently available spatiotemporal tracer concentration analysis, obtained from positron emission tomography (PET) . In many cases, however, the results obtained from the numerical simulations differ greatly from the experimental observations. While some numerical models commonly operate under the cubic law assumption, which defines a fracture as two perfectly parallel smooth surfaces, more advanced simulations include the effect of fracture surface roughness. Such results suggest the need of an improved understanding of transport heterogeneities as a function of fracture surface roughness and topography. Moreover, a systematic evaluation provides insight into the model complexity required for reliable radionuclide transport and flow predictability in potential host rocks.</p><p>In this study, we focus on the numerical modeling of flow through a fracture while taking into account surface roughness of the fracture walls, and validating the results against tomographic methods. For this purpose, the structural parametrization of the fracture is carried out by performing the segmentation of micro-computed tomography (µCT) images obtained from Granite samples from the Mrákotín quarry  in the Czech Republic. Subsequently, interferometry measurements of identical fracture material are carried out in order to quantify the details in the surface topography at the nm to µm scale. Resulting data are combined with µCT data through statistical methods, which provide a more meaningful definition of the surface topography, and are compared with numerically generated surface roughness. Resulting numerical simulations are then validated against PET measurements. As a result from the outlined workflow and the quantitative comparison, we provide suggestions of general applicability of the required degree of complexity for surface geometry segmentation in flow simulations.</p>

Energy Procedia

Abstract REPP-CO 2 is a Czech-Norwegian project representing a major step towards CO 2 storage in... more Abstract REPP-CO 2 is a Czech-Norwegian project representing a major step towards CO 2 storage in the Czech Republic. The project is an advancement towards a pilot project in geological settings with large CO 2 storage potential in the future. The presented work is focused mainly on static long-term laboratory experiments in CO 2 -rock-brine systems. Both equilibrium and kinetic geochemical modelling studies on CO 2 -rock-brine interaction were consequently carried out using geochemical program PHREEQC. The results from experiments and simulations could support the risk assessment argumentation of the storage site performance.

Energy Procedia

The genesis of the CO 2 storage resource management system (SRMS) Scott Frailey*, Illinois State ... more The genesis of the CO 2 storage resource management system (SRMS) Scott Frailey*, Illinois State Geological Survey; George Koperna, Advanced Resources International, inc; Owain Tucker, Shell Global Solutions Risk-based monitoring network design for geologic carbon sequestration sites

Wissenschaftliche Berichte Fzka, 2009

The study was focused on mobile organic matter quantification from the Ruprechtov natural analogu... more The study was focused on mobile organic matter quantification from the Ruprechtov natural analogue site (CZ) and its characterisation. Only a small fraction of sedimentary organic matter can be released into the solution: 2.8 %. The release rate is dependent on the organic matter composition and the degree of coalification. The mobile organic matter can be represented by extracted natural humic acid. The correspondence was clarified by MALDI-TOF MS spectra which showed high degree of similarity with those of organic substances from natural mobile organic matter in Ruprechtov groundwater and with those leached from the sediment in contact with solution. MALDI-TOF spectra also proved that the mobile organic matter consists of small independent molecules with molecular weight up to 1000 Da.

This is an Open-Access article distributed under the terms of the Creative Commons Attribution No... more This is an Open-Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/ by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited The article summarises the status and competence of UJV Rez, a. s. (up to 2012, the Nuclear Research Institute Rez, Czech Republic) in the field of radioactive waste (RAW) management as a company managing of 95% of institutional radioactive wastes in Czech Republic. UJV Rez a. s. has been one of the Czech Republic's key research and engineering institutions in the field of nuclear energy production since 1955. The company processes and conditions prior to storage 95% of so-called institutional RAW and is the principal partner of the state with respect to the research support of the Czech deep geological repository development project. UJV Rez a. s. boasts its own accredited radiochemical analytical test laboratory, unique of its kind in the Czech Republic. Of equal importance is UJV Rez's active participation in a range of international organisations and associations and its involvement in wide range of international projects, and so as European projects. One of them is EU funded project PREDIS: Pre-disposal management of radioactive wastes, that has started at September 2020, focused on the field of low level radioactive waste (LLW) and intermediate level radioactive waste (ILW) pre-disposal.

Journal of Radioanalytical and Nuclear Chemistry, 2013

ABSTRACT The transport of 3H+ (as HTO) and 36Cl− (as Na36Cl) was investigated in the dynamic syst... more ABSTRACT The transport of 3H+ (as HTO) and 36Cl− (as Na36Cl) was investigated in the dynamic system, i.e., in the columns filled with crushed pure granite and fracture infill of various grain sizes. The aim of column experiments was to determine important transport parameter, such as the retardation, respectively distribution coefficients, Peclet numbers and hydrodynamic dispersion coefficients. Furthermore, the research was focused to quantification of the effect of grain size on migration of studied radionuclides. The experimental breakthrough curves were fitted by a model based on the erfc-function, assuming a linear reversible equilibrium sorption/desorption isotherm, and the above mentioned transport parameters were determined. The results showed that influence of grain size on sorption of 3H+ and 36Cl− was negligible. Retardation and distribution coefficients of both tracers converged to one and zero, respectively, in case of all fractions of crushed granite and infill material. Generally, the presumed ion exclusion of 36Cl in anionic form was proved under given conditions, only very weak one seems to exist in a case of infill material. In principal, both radionuclides behaved as non-sorbing, conservative tracers. On the other hand, the influence of grain size on Peclet numbers value and on dispersion coefficient was observed for both crystalline materials, namely in agreement with theoretical suppositions that the values of Peclet numbers decrease with increasing grain size and values of dispersion coefficient increase.

International Journal of Global Energy Issues, 2014

Any geological disposal/storage facility must prove its safe performance prior to licensing, rega... more Any geological disposal/storage facility must prove its safe performance prior to licensing, regardless of whether the compound is solid radioactive waste (RW) or gaseous carbon dioxide (CO 2 ). The disposal/storage facility is considered safe if it meets the relevant safety standards and proves its reliable safe performance over defined timescales. This paper presents a crossnational comparison of the safety/risk assessment aspects of ultimate disposal facilities for RW and CO 2 in the Czech Republic, Switzerland, India, and Bulgaria, completed in an international project. In both fields, the main goal of safety assessments is to create a reliable evaluation of the disposal system performance over long timescales. The procedures are based on the following scheme: system description -system development description -model development -consequence analyses. Due to the long temporal and large

ASME 2009 12th International Conference on Environmental Remediation and Radioactive Waste Management, Volume 2, 2009

ABSTRACT Groundwater data from the natural analogue site Ruprechtov have been evaluated with spec... more ABSTRACT Groundwater data from the natural analogue site Ruprechtov have been evaluated with special emphasis on the uranium behaviour in the so-called uranium-rich clay/lignite horizon. In this horizon in-situ Eh-values in the range of −160 to −280 mV seem to be determined by the SO42−/HS− couple. Under these conditions U(IV) is expected to be the preferential redox state in solution. However, on-site measurements in groundwater from the clay/lignite horizon show only a fraction of about 20% occurring in the reduced state U(IV). Thermodynamic calculations reveal that the high CO2 partial pressure in the clay/lignite horizon can stabilise hexavalent uranium, which explains the occurrence of U(VI). The calculations also indicate that the low uranium concentrations in the range between 0.2 and 2.1μg/l are controlled by amorphous UO2 and/or the U(IV) phosphate mineral ningyoite. This confirms the findings from previous work that the uranium (IV) mineral phases are long-term stable under the reducing conditions in the clay/lignite horizon without any signatures for uranium mobilisation. It supports the current knowledge of the geological development of the site and is also another important indication for the long-term stability of the sedimentary system itself, namely of the reducing geochemical conditions in the near-surface (30m to 60 m deep) clay/lignite horizon. Further work with respect to the impact of changes in redox conditions on the uranium speciation is on the way.

Journal of Radioanalytical and Nuclear Chemistry, 2015

ABSTRACT Isotopes of caesium and selenium belong among fission products, being present in spent n... more ABSTRACT Isotopes of caesium and selenium belong among fission products, being present in spent nuclear fuel (SNF) and high level waste (HLW), and contribute significantly to the risk associated with SNF and HLW disposal in deep geological repositories. The present work is focused on sorption behaviour of Cs and Se species on two types of crystalline rock, granite from Melechov massif (Czech Republic) and Äspö diorite from the underground laboratory Äspö (Sweden). The aim was to compare sorption behaviour of Cs and Se on these rocks under aerobic and anaerobic conditions and determine the influence of redox conditions on their kinetic sorption properties.

Uranium, Mining and Hydrogeology, 2008

Natural analogue study at the Ruprechtov site (Czech Republic) was aimed to investigate and under... more Natural analogue study at the Ruprechtov site (Czech Republic) was aimed to investigate and understand the behaviour of natural radioelements in sedimentary formation. The isotopic exchange tests with 233U were used to compare the results of exchangeable uranium (Uex) determination with the results of the first steps of sequential leaching tests. Measured interaction isotherms showed a significant dependence of uranium

Fourth EAGE CO2 Geological Storage Workshop, 2014

ABSTRACT Safety of any waste storage is based on safety functions of storage system components. C... more ABSTRACT Safety of any waste storage is based on safety functions of storage system components. CO2 storage multibarrier system comprises of injection borehole casing, cement, used for infill and plug and host rock. Their performance and behaviour in both short term and long term periods has to be studied in order to evaluate changes of the materials under CO2 and underground condition influence. The anthropogenic material changes are the most important parameters for injection borehole integrity and potential CO2 leakage. The presented results demonstrate interaction of materials that should fulfill safety function in the multibarrier CO2 storage system. Steel samples, cement and host rock samples were studied under long-term interaction with spCO2. Material and their property changes were then evaluated using XRD, TEM and BET measurements.

Fourth EAGE CO2 Geological Storage Workshop, 2014

ABSTRACT Based on selection and also on availability of suitable core samples, reservoir rocks fr... more ABSTRACT Based on selection and also on availability of suitable core samples, reservoir rocks from 3 geological structures were selected for the experiments. The samples were exposed to spCO2 under 7,5 MPa and 35C for 3 month. Long term static experiment revelead that selected rock samples kept their properties regardless spCO2 exposure. Such an information would be important studying the suitability of reservoir structure for CO2 exposure as mineral changes are the most important parameter for potential injectability and storativity evaluation.

Uranium, Mining and Hydrogeology, 2008

The behaviour of acid contaminantion in fucoid sandstone was studied on samples from Straz pod Ra... more The behaviour of acid contaminantion in fucoid sandstone was studied on samples from Straz pod Ralskem, Czech Republic. Long term leaching of solid phase cores of contaminated fucoid sandstone with very low value permeability about 0.6 mD by background groundwater from Cenomanian aquifer was performed and possible chemical reactions were proposed. Results of leaching and modified extraction method divided core