lecturers-barbaraBarbara Čenčur Curk, Ph.D., assistant professor at the University of Ljubljana, Faculty of Natural Sciences and Engineering, Department of Geology.
She has over 20 years experiences in various field of hydrogeology. She started her career at the Institute of Mining, Geotechnology and Environment, where she gained professional experiences in geological, geotechnological and hydrological investigations of landslides; various hydrogeological studies; environmental impact assessments and environmental and hydrogeological aspects of waste disposal sites. Moreover, she was also involved in national and European research projects concerning solute transport through the soil and unsaturated zone of karst-fractured rock and coarse gravel aquifers. In the last 10 years she was a part-time teacher at the University of Nova Gorica and University of Ljubljana, where she is now fully employed. In the last years she was collaborating in European transnational and cross-border projects concerning water management and climate change impacts on drinking water resources.

Lecture description:

Coarse gravel aquifers – from detailed studies to management of drinking water supply

The Ljubljana field aquifer is one of the biggest unconfined porous aquifers in Slovenia and is a very important drinking water source. More than half of the aquifer area lies below the city, thus there is several decades of evidence showing changes in groundwater quality and quantity. The most endangered water well field is Hrastje, where human activities in the area degraded groundwater quality in the past. The aquifer consists of very coarse gravel (particle sizes ranging up to 50 mm and more) and is very heterogeneous. The heterogeneities consist of several clay and conglomerate lenses, which drive the parameter variability and create large uncertainties reflecting complicated hydraulic and chemical processes. Therefore, detailed studies of these processes have to be performed on a small and large scale.
For determining water transport in variably saturated porous media we need the soil water retention curve and the hydraulic conductivity function. A combination of the simplified evaporation experiment (HYPROP) and the dew point method (WP4 PotentiaMeter) was used to obtain the information across a wide moisture range on natural, albeit adjusted samples (sieved to fine (diameter <2 mm) and coarse (diameter <8 mm) samples). Results on coarse samples were compared with the calculated results according to mass-based gravel correction. In order to study pollution transport, several tracer experiments were carried out in the past. Despite a great risk, the experiments were performed on the catchment area of the Hrastje waterworks, inside the second water protection zone. During the experiments the water from Hrastje waterworks was still in use for drinking water supply. A water supply management system regarding optimization of water extraction and land use restrictions under climate change scenarios was set up. Several management options regarding water quantity were selected and evaluated: (i) establishing of new water well field, (ii) artificial recharge with infiltration wells, (iii) implementation of farming restrictions in the first and second safe guard zone (compensations because of lower farming production) and (iv)drinking water treatment.