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Povzetek: The distribution of the high concentrations of arsenic (As) and fluoride (F-) in groundwater on a Pan-European scale could be explained by the geological European context (lithology and structural faults). To test this hypothesis, seventeen countries and eighteen geological survey organizations (GSOs) have participated in the dataset. The methodology has used the HydroGeoToxicity (HGT) and the Baseline Concentration (BLC) index. The results prove that most of the waters considered in this study are in good conditions for drinking water consumption, in terms of As and/or F- content. A low proportion of the analysed samples present HGT≥ 1 levels (4% and 7% for As and F-, respectively). The spatial distribution of the highest As and/or F- concentrations (via BLC values) has been analysed using GIS tools. The highest values are identified associated with fissured hard rock outcrops (crystalline rocks) or Cenozoic sedimentary zones, where basement fractures seems to have an obvious control on the distribution of maximum concentrations of these elements in groundwaters.
Ključne besede: trace elements, arsenic fluoride, groundwater, geo-hydrochemistry, spatial analysis
Objavljeno v DiRROS: 30.01.2023; Ogledov: 783; Prenosov: 105
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Povzetek: This work aims at evaluating mercury (Hg) occurrence, spatial distribution and speciation in groundwater of the Isonzo/Soča River upper alluvial plain downstream from the Idrija Hg mine (Western Slovenia). Several wells and piezometers were sampled both in static and dynamic mode. On the basis of hydrochemistry and isotopic composition, the main sources of groundwater were established. Hg concentrations in the Slovenian sector, supplied by local rainfall, are comparable to values measured close to the Isonzo River. Possible further Hg local sources have been suggested. Stability field analysis for the aqueous Hg species revealed that in the presence of chloride Hg solubility may be increased by the formation of chlorocomplexes. Mercury that rarely enters reduced surrounding conditions can be bound to sulphur to form polysulphide species depending on the pH of water. Since Hg-contaminated alluvial sediments of the Isonzo River may act as a secondary Hg source in groundwater, a borehole was dug down to the water table. Mercury content and speciation revealed that cinnabar (HgS) is the prevalent form followed by the matrix-bound Hg (Hgbound). Variations of the physico-chemical boundary conditions, as well as the raising/lowering of the water table, may be locally responsible for the slight variability of Hg concentrations in the aquifer.
Ključne besede: aquifers, groundwater, mercury
Objavljeno v DiRROS: 22.06.2022; Ogledov: 336; Prenosov: 178
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Povzetek: Slope stability strongly depends on the prevailing hydrological and hydrogeological conditions. The amount and intensity of precipitation and changing groundwater levels are important landslide triggering factors. Environmental tracers, including the chemical and stable isotope compositions of precipitation and groundwater, were used to gain insight into the groundwater dynamics of the Urbas landslide. The landslide is situated in a mountainous area with steep slopes and high precipitation amount and poses a high risk for the safety of the Koroška Bela settlement that lies downstream. The stable isotope analyses of oxygen-18 (18O) and deuterium (2H) in the precipitation and groundwater were used to estimate the groundwater mean residence time and the average altitude of the landslide recharge area. This information will help to plan and prioritize remedial landslide measures aiming to reduce the recharge of the landslide body and, thus, lower the risk of transformation of the sliding material into debris flow. The results of the chemical analysis of samples taken from springs and a piezometer show a Ca–HCO3 water type. This indicates low water–rock interaction in a landslide area composed of Upper Carboniferous and Permian clastic rocks and points to upper laying carbonate rocks and scree deposits as the main recharge area. Water samples for stable isotope analyses of δ18O and δ2H were collected from a rain gauge, springs, and a piezometer over a two-year period (2018–2020). The estimated mean recharge altitude of the groundwater at sampling points was from approximately 1700 to 1800 m a.s.l. with a mean residence time of 2–5 months.
Ključne besede: landslide, groundwater, stable isotopes, oxygen-18, deuterium, hydrogeology, recharge dynamic
Objavljeno v DiRROS: 16.03.2022; Ogledov: 499; Prenosov: 220
Celotno besedilo (3,55 MB)

Povzetek: Triglavska Bistrica is a typical Alpine river in the north-western part of Slovenia. Its recharge area includes some of the highest peaks in the Julian Alps. The hydrogeological conditions and flow of the river depend largely on groundwater exchange between the karstified aquifer in the carbonate rocks and the intergranular aquifer in the glaciofluvial deposits. The average volume of the river flow is up to several m3/s. In this study, water samples from different locations along the river were analysed for stable isotope ratios of oxygen and hydrogen, major ions, and concentration of tritium activity. The correlation of major ions suggests that the recharge area consists of both limestone and dolomite rocks. The δ18O and δ2H values decrease downstream, implying that the average recharge elevation increases. At the downstream sampling site V-5, located approx. 300 m upstream from the confluence of the Sava Dolinka River, the calculated mean recharge altitude is estimated to be 1,996 m.
Ključne besede: groundwater, oxygen and hydrogen isotopes, hydrogeochemistry, recharge area, Alpine aquifer, Slovenia
Objavljeno v DiRROS: 09.03.2022; Ogledov: 658; Prenosov: 218
Celotno besedilo (3,01 MB)

Povzetek: In Europe, emerging organic compounds (EOCs) in groundwater is a growing research area. Prioritisationfor monitoring EOCs in Europe was formalised in 2019 through the development of thefirst voluntarygroundwater watch list (GWWL). Despite this, groundwater occurrence data in the peer reviewedliterature for Europe has not been reviewed to date. Questions surrounding the effect, toxicity, move-ment in the subsurface and unsaturated zone make the process of regulating EOC use difficult. The aim inEurope is to develop a unified strategy for the classification, and prioritisation of EOCs to be monitored ingroundwater. This paper compiles evidence from the recent published studies from across Europe, since2012, when the last major literature global review of EOCs in groundwater took place. A total of 39studies were identified for review based on specific selection criteria (geography, publication date,sample size>10, inclusion of EOCs data). Data on specific compounds, and associated meta-data, arecompiled and reviewed. The two most frequently detected EOCs, carbamazepine and caffeine, occurredin groundwater at concentrations of up to 2.3 and 14.8mg/L, respectively.
Ključne besede: emerging organic chemicals, environmental exposure, groundwater contaminants, compounds of concern, groundwater hazards
Objavljeno v DiRROS: 13.01.2021; Ogledov: 1224; Prenosov: 601
Celotno besedilo (1,90 MB)