Petar Papic

Elements of groundwater protection in a karst environment

The large spread of karst in Yugoslavia (over one third of the territory) and the importance of its water resources due to the growing pollution of the environment lead to complicated research activities in various scientific fields. A multidisciplinary approach to this research should have the following basic directions: defining sources of pollution; classification of pollutants; defining hydrological, geological, and hydrogeological characteristics of the area studied; study of interaction among pollutants, groundwater, and rocks; and, finally, defining of specific protection measures. The prerequisite for any decision making should already exist in local and regional urban plans. Some basic principles of the listed directions of research are illustrated by examples from practice.

Hydrochemical characteristics of mine waters from abandoned mining sites in Serbia and their impact on surface water quality

Upon completion of exploration and extraction of mineral resources, many mining sites have been abandoned without previously putting environmental protection measures in place. As a consequence, mine waters originating from such sites are discharged freely into surface water. Regional scale analyses were conducted to determine the hydrochemical characteristics of mine waters from abandoned sites featuring metal (Cu, Pb–Zn, Au, Fe, Sb, Mo, Bi, Hg) deposits, non-metallic minerals (coal, Mg, F, B) and uranium. The study included 80 mine water samples from 59 abandoned mining sites. Their cation composition was dominated by Ca2+, while the most common anions were found to be SO42− and HCO3−. Strong correlations were established between the pH level and metal (Fe, Mn, Zn, Cu) concentrations in the mine waters. Hierarchical cluster analysis was applied to parameters generally indicative of pollution, such as pH, TDS, SO42−, Fe total, and As total. Following this approach, mine water samples were grouped into three main clusters and six subclusters, depending on their potential environmental impact. Principal component analysis was used to group together variables that share the same variance. The extracted principal components indicated that sulfide oxidation and weathering of silicate and carbonate rocks were the primary processes, while pH buffering, adsorption and ion exchange were secondary drivers of the chemical composition of the analyzed mine waters. Surface waters, which received the mine waters, were examined. Analysis showed increases of sulfate and metal concentrations and general degradation of surface water quality.

Specific chemical composition of karst groundwater in the Ophiolite Belt of the Yugoslav Inner Dinarides: A case for covered karst

The Ophiolite Belt of the Yugoslav Inner Dinarides, for its very complicated tectonic fabric, according to the existing geological theories was considered to be a chaotic melange of the olistostrome type. Its parts of Triassic limestone were understood as thin slide sheets over ophiolites (diabases, cherts, ultramafics). Complex hydrogeological researches, conducted in the last few years, refuted such theories. They showed that Triassic limestone is much wider spread and is covered with ophiolites of Jurassic age. Results of hydrochemical analysis were among ones of most importance. Established relationships between main chemical components in groundwaters of the area, made concluding about the origin of karst groundwaters, properties of karst aquifers, and influences of ultramafics on them, possible. With typical examples it is shown what conclusions can be made according to content of calcium, magnesium, and silica, their relationships, Ca2+/Mg2+ ratio, and temperature. Results collected during regional studies indicate that recharge of karst aquifers with groundwater from ultramafics can be significant.

Mineral and Thermal Waters of Serbia: Multivariate Statistical Approach to Hydrochemical Characterization

A new approach using hydrochemical characterization of mineral water in Serbia was applied in this paper. After field research and groundwater sampling, laboratory measurements were conducted. Trace and ultratrace elements in 174 samples of mineral water were analyzed using HR ICP–MS and methods to determine gross alpha/beta activities were applied. Hierarchical cluster analysis (HCA) was used on selected variables: major ions (Ca, Mg, Na, Cl, HCO3, SO4), Si, temperature, electrical conductivity (EC), pH and Eh. Results showed that variability of chemical characteristics, and diverse mineral and thermal water types were grouped into six clusters. Geochemical conditions of each cluster were considered in detail in terms of basic hydrochemical parameters, geological characteristics, and the contents of particular elements. There were certain regularities among the separated groups. Water differed in temperatures, dissolved mineral substances, pH, Eh values and gas content, which indicated different hydrogeological conditions. Variations among clusters in natural radioactivity, the content of essential elements and rare earth elements (REE) are also discussed.

Geochemistry of Bottled Waters of Serbia

Chemical analyses of 13 bottled mineral waters were carried out at the BGR geochemical laboratories. The analyses included pH, electrical conductivity, alkalinity and concentrations of 69 elements and ions. An aquifer lithology impacts on the chemical composition of ground water significantly, especially on the explanation of conditions of forming and circulation of ground water through different lithology environments. Basic composition of ground water is usually a reflection of the lithogeochemistry of the aquifer, while micro components indicate the circulation of ground water through the different lithological environment. The waters are most frequently tapped from Neogene carbonate rocks (dolomite, limestone), and to a lesser extent from granitoid rocks, shale, and serpentinite. Based on the analyses of bottled mineral waters, it has been observed that water quality is greatly affected by the chemical composition of igneous intrusions, regardless of the fact that the analysed waters have been sampled from different aquifers (Neogene sediments, limestone, flysch, schist). Bottled waters of Serbia are mostly HCO3-Ca, HCO3-Ca-Mg (from carbonate rocks) and HCO3-Na (from Neogene and igneous rocks). Among the micro components, increased concentrations of Cs, Ge, Rb, Li, and F are frequently present in bottled water, as a consequence of its circulation through granitoid rocks. Some samples contain a higher concentration of B, I, NH4, Tl, W, as the consequence of the aquifer environment.

Uranium minerals of Bukulja mountain controls on storage reservoir water

Headwaters of the Bukulja stream on southern slope of Bukulja Mountain were confined in 1976 by the Garasi Dam for water supply to Aranđelovac and nearby communities. Geological explorations from 1949 detected several uranium occurrences on Bukulja Mt. and later identified uranium mineral deposits. This work considers the trend of total beta-particles radioactivity in the Garasi storage reservoir for the period 1991-2004. Samples for radioactivity analyses were collected from three depth levels near the dam: directly below the lake surface, at the lake mid-depth and above the lake bottom. A highly plausible assumption is that the rising trend of total beta radioactivity in Garasi lake water is genetically associated with the geological nature of the terrain.

Natural attenuation of petroleum hydrocarbons—a study of biodegradation effects in groundwater (Vitanovac, Serbia)

The role of natural attenuation processes in groundwater contamination by petroleum hydrocarbons is of intense scientific and practical interest. This study provides insight into the biodegradation effects in groundwater at a site contaminated by kerosene (jet fuel) in 1993 (Vitanovac, Serbia). Total petroleum hydrocarbons (TPH), hydrochemical indicators (O2, NO3−, Mn, Fe, SO42−, HCO3−), δ13C of dissolved inorganic carbon (DIC), and other parameters were measured to demonstrate biodegradation effects in groundwater at the contaminated site. Due to different biodegradation mechanisms, the zone of the lowest concentrations of electron acceptors and the zone of the highest concentrations of metabolic products of biodegradation overlap. Based on the analysis of redox-sensitive compounds in groundwater samples, redox processes ranged from strictly anoxic (methanogenesis) to oxic (oxygen reduction) within a short distance. The dependence of groundwater redox conditions on the distance from the source of contamination was observed. δ13C values of DIC ranged from − 15.83 to − 2.75‰, and the most positive values correspond to the zone under anaerobic and methanogenic conditions. Overall, results obtained provide clear evidence on the effects of natural attenuation processes—the activity of biodegradation mechanisms in field conditions.

Mineral Waters of Montenegro

Mineral water resources, and especially thermal water resources, are relatively sparse in Montenegro. This is a result of the specific geological makeup and complex tectonic relationships. However, due to insufficient insight into the origin of these water resources, particularly the hydrogeological conditions, as well as geochemical relationships, as surveys in this area have been relatively modest in terms of both extent and scope, no optimal results have been achieved that would enable the utilization of these water resources for useful purposes. Mineral and thermal waters are found in three hydrogeological zones of Montenegro: coastal, central and Inner Dinarides. Five types of mineral water are allocated on the basis of hydrochemical characteristics: Na–Cl; Ca–HCO3; Mg, Ca–HCO3 with CO2; Na, Ca–HCO3 with CO2 and Na–HCO3, Cl with CO2.

Hydrogeologic structures in two Serbian spa towns - Sijarinska Banja and Selters Banja

The objective of the paper is to identify the boundaries of hydrogeologic structures in which natural mineral waters occur, using two examples: old mineral water (Sijarinska Banja) and young mineral water (Selters Banja). The research addresses the distance from recharge zones, depth of occurrence, and points of discharge. Apart from the three spatial dimensions, the study also includes the time dimension – water age. The following parameters are examined: geologichydrogeologic conditions in the places of occurrence of mineral water, connection between mineral water and permeable fault zones, distance of surface water divides, previously-defined maximum possible depths of occurrence, possible flow rates, and the determined age. If the flow followed a straight line, the maximum distance of the recharge zone would be up to 7 m for the young and up to 11 km for the old mineral water. However, it is obvious that this is never the case in fractured systems, given that water travels much longer distances from the point of entry to the point of drainage from aquifers. Assessment of geologic-hydrogeologic and hydrodynamic conditions, relative to the determined age of the mineral water, leads to the conclusion that the distance between the recharge and drainage zones can be less than 5 km. The paper shows that insight into the depth of infiltration into permeable fault zones can also be gained by studying the depth of circulation relative to known hydrodynamic zones. The inference is that the largest amount of groundwater is restored in the hydrodynamic zone of slow groundwater renewal, which is below a depth of 1.5 km at Sijarinska Banja and below 1.3 km at Selters Banja.

Hydrogeochemistry of Uranium in the Groundwaters of Serbia

For the present study, 172 groundwater samples (collected from wells and natural springs in Serbia) were analyzed for different chemical parameters including uranium. For each groundwater sample, information was compiled about the basic parameters of its chemical composition. Most of the samples were found to be of the Na – HCO3 and Ca, Mg − HCO3 water types, while only a few were classified as the Ca, Mg – SO4 or Na − Cl type. HR–ICP–MS is an analytical technique used for uranium determinations. The measured concentrations of uranium were in the range from 0.0005 μg/L to 25.34 μg/L.