The article describes basic chemical properties of the Kamniško-Bistriško polje aquifer groundwater. The aquifer is composed of the upper aquifer in sand and gravel deposits of the Kamniška Bistrica river and of the lower, dolomite aquifer. The water of both aquifers differs significantly as to its chemical composition. Compared to the lower aquifer, the water of the upper aquifer is more mineralized and also more loaded with pollutants originating from agricultural activities. On the basis of chemical properties of groundwater from both aquifers it can be concluded that the recharge area of both aquifers is different; the upper aquifer is recharged mainly by precipitation and infiltration of the Kamniška Bistrica river, while the larger quantity of water from the lower aquifer is estimated to originate from carbonate rocks on the western fringes of the Kamniško-Bistriško polje.
The study deals with radionuclides in precipitation, the source of groundwater in the aquifers. This paper evaluates the results of measurements and the impact on the environment. Tritium levels in precipitation are indispensable information to determine the age of groundwater. The paper also looks dry deposition.
Most gamma emitters in groundwater samples are close to the limits of detection, so precise and accurate measurements are very pretentious. To ensure the quality of results that is required within the project Dating of groundwater in deep aquifers Slovenia, it was necessary to find all the parameters in a method that can be improved, upgraded the model and built the knowledge into the software procedures for the calculation of the sample activities. The first step was a good characterization and knowledge of the counting background of gamma spectrometers and its reduction. Papers no. 1, 3 and 4 address the impact of radon, thorium and uranium species in the background counting. Usage of Bayesian statistics is effective in reduction of uncertainties, which are always high close to the detection limits.