The aim of this thesis was a qualitative and a quantitative analysis of the function of soils in natural and artificial substrates, i.e. mining dumps, as sources and sinks for substances dispersed by uranium mining activities in eastern Thuringia, Germany. For this purpose soil and soil water samples were taken from a covered mining dump and from a floodplain adjacent to two mill tailings ponds. A geochemical analysis allowed the determination of the input, distribution and mobilisation probability of mining related metals (U, Pb, Cu, Ni, Ba) and other substances (Cl-, SO42-, Na+, Ca2+, Mg2+).
Atmospheric or biogenic depositions on the surface of the covered heap are responsible for the enrichment of carbon and other mining related substances . Additionally, in the lower part of the covering, capillary ascending water causes the accumulation of carbon, heavy metals, and sulphur. These typical mining related substances are released due to decay of the carbon, sulphur, and heavy metal rich substrates, which build up the heap. Carbon is the most important sink for mining related pollutants; thus the accumulation in the covering has to be rated positively.
The sample sites in the floodplain were located upstream, in between, and downstream from two mill tailings ponds. On the basis of the latter two sample sites it was possible to prove that the input of mining related substances originate from these two ponds. In general there is a negative gradient of the content of heavy metals in the soils and a long term fixation is guaranteed due to high contents of soil organic matter and pedogenetic oxides. While the enrichment of mining related substances in soils between the two mill tailings ponds is caused by capillary or ground water ascent, the contamination of the soils downstream from the tailings ponds can be attributed to flood events or dam failures. The possibility of mobilisation of heavy metals is very low because of their strong fixation in the soils. However, high concentrations of uranium were detected in the soil waters indicating that the polluted floodplains may become sources of uranium in the future.
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The aim of this thesis was a qualitative and a quantitative analysis of the function of soils in natural and artificial substrates, i.e. mining dumps, as sources and sinks for substances dispersed by uranium mining activities in eastern Thuringia, Germany. For this purpose soil and soil water samples were taken from a covered mining dump and from a floodplain adjacent to two mill tailings ponds. A geochemical analysis allowed the determination of the input, distribution and mobilisation probabil...
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