Porosity-permeability relations are simulated for a precipitation-dissolution cycle in a virtual sandstone. A hysteresis in permeability is observed depending on the geochemical process and dominating reaction regime, whereby permeability varies by more than two orders of magnitude. Controlling parameters for this hysteresis phenomenon are the closure and re-opening of micro-scale flow channels, derived from changes in pore throat diameter and connectivity of the pore network.

Safety assessments must demonstrate that radionuclides in potential disposal sites are retained within the containment providing rock zone using reactive transport simulations. Here, this is quantified for the example of uranium in the hydrogeological system of the Opalinus Clay at Mont Terri. Our work clearly shows how sensitive migration lengths resulting from simulations are to the model conceptualisation and selection of underlying data.

The TRANSPORT Simulation Environment (TRANSPORTSE) was coupled with the geochemical reaction module PHREEQC, providing multiple new features that make it applicable to complex reactive transport problems in various geoscientific fields. Two computationally demanding and complex geochemical benchmarks were used in the present study to successfully verify the code implementation.

The geothermal hot water reservoir below the small town of Waiwera in New Zealand has been known to the indigenous Maori for many centuries. Overproduction by European immigrants led to a water level decrease and consequently artesian flow from the wells and the seeps on the beach ceased. The Te Kaunihera o Tāmaki Makaurau Auckland Council established the Waiwera Thermal Groundwater Allocation and Management Plan to allow the geothermal system to recover.

Within the Cheap-GSHPs and GEO4CIVHIC projects, innovations were advanced in the field of ground heat exchangers design for shallow geothermal systems. Among these, a metallic type has been proposed that can be installed in direct contact with the underground. As carbon steel is prone to corrosion and corrosivity varies based on site-specific underground conditions, a laboratory assessment methodology was applied to metal samples to assess the corrosion rate and forecast the durability.

The present study, uses density-driven flow and transport models to evaluate mechanisms of saline water intrusion from deep aquifers into the freshwater column used for drinking water supply under different boundary conditions and for a specific site in the German Federal State of Brandenburg. Results show that mainly decreasing groundwater recharge leads to increased and earlier salinisation which highlights the need for waterworks to initiate effective countermeasures quickly and in time.

For a potential utilisation of coal resources located in Hungary, an assessment of groundwater pollution resulting from a water-borne contaminant pool has been undertaken. A sensitivity analysis was carried out by means of numerical simulations. Simulation results demonstrate that fluid flow via the regional faults is the main driver for a potential contamination of shallow groundwater aquifers. A parameter correlation analysis is presented.

The quantification of the impacts on the environment and human health is a crucial prerequisite for geological sub-surface utilisation projects. With the presented approach, the shortcomings of using conceptually simplified models are substantially reduced, since subsurface complexities are accounted for. The transparency of the assessment basis should generally increase the acceptance of geoengineering projects, considered one of the crucial aspects for geological subsurface utilisation.

The moving distance of the diffusion front is farther away the canister center, along the direction with the neighboring layer having lower diffusion coefficient. When the bedding angle increases, the diffusion front moves farther in z+ direction, reflecting the increase in effective diffusivity and higher impact of parallel-to-bedding diffusion. The neighboring layers can slightly reshape the diffusion front line of the radionuclide.

This paper presents the implementation of probabilistic analyses to assess environmental risks while improving the productivity of the in situ coal conversion process. Parametric modelling was employed for the Máza–Váralja (Hungary) coal deposit, and parameter uncertainty was undertaken to identify the potential risks to human health and the environment. The outputs of the parametric study focused on assessing reactor stability, fault integrity, surface subsidence, and hydraulic processes.

In 2019, a fiber optic cable was installed in the middle of a deep geothermal production well to the reservoir in Munich, Germany. This cable hangs freely below the pump and allows continuous measurements of the temperature at every meter of the cable. The well was put into operation for the first time in the summer of 2021. We used the fiber optic cable to monitor the temperature profile during production in the reservoir and to quantitatively interpret the flow zones using an inverse model.

The mathematical basics of a numerical code developed specifically for the search of a site for high-level radioactive waste in Germany is presented. The code is developed in accordance to the specific regulations. First tests of the code are shown.

This study evaluates the structural geological requirements for the city of Minden, Germany, in order to provide thermal energy for domestic, commercial or even industrial usage. The structural geological modeling and the interpretation of a regional seismic line show possible geothermal reservoirs within different Mesozoic stratigraphic units (e.g. Keuper and Middle Bunter sandstones) at varying depths up to 4,100 m including temperatures obtained through analytical calculations above 150°C.

Storm Kyrill in January 2007 was one of the worst storms in northern Europe over the past 50 years. The paper presents an overview of the infrastructure and societal impacts of the storm from a compilation of media sources. Energy meteorology impacts were prominent in the large number of power cuts in Europe. An analysis is made of tide gauge data around the North Sea to assess if there had been a recurrence of the rogue wave event at FINO1 from Storm Britta on 1 November 2006.

Metakaolin-based geopolymers with a Ca(OH)2 activator are investigated in the context of stone-built heritage conservation. The results of the reactivity tests are compared to the results of geopolymers with more well-known activators like NaOH and KOH. Subsequently, the physico-mechemical properties of the geopolymer with Ca(OH)2 is also investigated, in combination with standardized aggregates of marl powder, limestone powder and quartz sand.

The overall impact of climate change is a decrease in the frost damage risk of masonry walls in Tønsberg, Norway. However, an increased frost damage risk is expected from the present to the future conditions for the walls of small, conditioned rooms with higher driving rain load and lower solar radiation gains. Moreover, the freeze-thaw events experienced by the masonry walls of unconditioned, leaky buildings are 20 times more than the ones for the small, conditioned rooms.

The overall objective of the CHENILLE project is to performed an in-situ experiment in the Underground Reaserch Laboratory of Tournemire (Southern France) consisting of hydraulic and thermal stimulation of a fault zone. This experiment is monitored with extensive geophysical means (passive seismic, active seismic, distributed fiber optics for temperature measurements) in order to unravel the physical processes taking place during the stimulation for a better charactization of fault zones.

Data on geothermal properties are notoriously scarce, both on a good temporal and spatial resolution. We compared two data sets of a geothermal well in Bavaria (one had yearly analyses of a great number of ions, the other one tested the water every five minutes but only on a small number of variables) and found that yearly data systematically neglect seasonal variations taking place in the aquifer. Virtual sensors might help to combine the two data sets when the aquifer is well known.