The first remediation of contaminated soils in Črna na Koroškem, Žerjav and Mežica was carried out in 2008 under the program of measures for improving the state of the environment in the Upper Mežica valley. The aim of remediation measures was to minimize transfer of heavy metals from soils into human organisms. Children are the most endangered group due to their contact with the soil by playing in nature. Lead content in the blood of children showed that overlaying of contaminated land with clean soil is a fast and effective measure that reduces Pb input. The aim of our research was to verify the effectiveness of soil remedial action by soil monitoring. Replaced unpolluted soils could be contaminated again due to the bioaccumulation, ascendant flows and emission of dust particles from the contaminated environment. The research aim was to determine vertical and horizontal distribution of Pb, Zn and Cd content after five years of the implementation of the remediation measures. The replacement of upper soil layer was used in the Črna kindergarten, while soil overlaying was used in the Mežica kindergarten. The soil properties and the content of Pb, Zn in Cd was carried out in the soil samples taken from soil profiles and from soil probes. Analysis of heavy metals showed the evident difference from low to higher values at depths of 20–25 cm, on the boundary between new and old soil layer. We determined there has not been any measurable surface contamination of the upper soil layer in Črna, however Cd and Pb content in the top soil in Mežica indicated a slight increase of these elements. The kindergarten in Mežica was initially a more polluted environment, and the thickness of the clean soils on the surface was smaller than in Črna. There is no discernible difference in efficiency between either overlaying or replacing the contaminated soil.
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