Organic pollutants enter the groundwater as well as drinking water due to various anthropogenic activities on the surface of the aquifer. The purpose of the research within the framework of the doctoral dissertation was to investigate the presence, degradation and the dynamics of organic pollutants in groundwater and to determine their anthropogenic origin. Special attention was paid to the study of the dynamic processes of three pharmaceuticals, propyphenazone, caffeine and carbamazepine, in the unsaturated zone. On the basis of the combined tracking experiment, we determined the hydraulic properties of the unsaturated zone of the aquifer and the parameters of sorption (Kd) and degradation (?, T1/2 ) of propyphenazone and caffeine. The breakthrought curves for carbamazepine, with advection- disperzion eqations, could not be modelled with Hydrus 1-D program, which indicates more complex transport mechanisms for the compound. We found that caffeine has the lowest sorption capacity (average Kd = 0.027), but it decays rapidly (the highest T1/2 = 69.31 days). The coefficient of sorption of propyphenazone is higher, and its degradation compared to caffeine is slower (the highest T1/2 = 92.42 days). At the Dravsko polje aquifer, these three compounds were not detected above the detection limit of the analytical method. In the three- year research period, 382 organic compounds were found in the groundwater of the Dravsko polje aquifer with the passive sampling method. Among the compounds, the largest percentage was the unknown compounds (29 %), followed by 27 % of urban compounds, among which there were also pharmaceuticals, 19 % of pesticides, 7 % of solvents and 19 % of other compounds, including industrial compounds. The passive sampler method has proved to be a very useful tool for the preliminary determination of the presence of pollutants in groundwater. For each type of pollution, we have identified typical indicators of agricultural, urban and industrial impacts on groundwater. We showed the links between the appearance of pollutants, the properties of pollutants, pollution sources and hydrogeological conditions on maps, which were made on the basis of the multiple linear regression calculations. By statistical analysis, it was found that the occurrence of a particular type of pollutant is influenced by the direction of the groundwater flow, the coefficient of permeability, as well as the thickness of the unsaturated and saturated area. Agricultural areas are the most important areas for the presence of the agricultural pollutants group; while the sewerage network, railways, roads, agricultural land and forest influence the group of urban pollutants. In addition to hydrogeological conditions, the impact of the urban hinterland, roads and railways is also responsible for the presence of industrial pollutants in groundwater.
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