Assessment of elements mobility in anthropogenic layer of historical wastes related to glass production in Izera Mountains (SW Poland).

A geophysical survey conducted in the remote forest glade, located in the Izery Mountains (SW Poland), revealed the existence of an anthropogenic layer of historical glass wastes dumped in this area during the activity of a glass factory in the 18th and 19th centuries and domestic wastes dumped during the second part of the 20th century. The aim of the study was assessment of potential ecological risk related to the release of potentially toxic elements to the soil, groundwater and surface waters. The assessment was done on the base of classical geochemical analysis supported by calculation of environmental indices as well as on mobility of elements (leaching test and BCR sequential extraction). As an innovative aspect in the geostatistical interpretation of the data, some magnetic parameters (magnetic susceptibility-χ, χ/Fe ratio) were also used. It allowed for a better understanding of the relationship of PTEs with various forms of iron. The BCR sequential extraction found that among the PTEs, only Zn (up to 43%) was in a potentially mobile fraction probably occurring in ionic form, associated with iron oxides only by surface adsorption forces. The leaching has shown a slight increase in Zn and Cu content in the surface waters; however, it was not considered to be a real ecological threat because the pH of the waste material and soil cover is >6.0 and the scenario of a radical decrease in pH is rather unrealistic. The other PTEs were associated with more stable E2, E3 and E4 fractions. Zinc, similar to Ni, Co and Cu in waste samples, was highly correlated with magnetic parameters (χ and χ/Fe). It means that a considerable part of these metals was associated with ferrimagnetic iron oxides, although they can also occur in the form of inclusions in aluminosilicates and enclosed in glassy phases.

Integrated geophysical and geochemical methods applied for recognition of acid waste drainage (AWD) from Zn-Pb post-flotation tailing pile (Olkusz, southern Poland).

Long-term underground exploitation of Zn-Pb ores has led to drainage of the area and formation of a huge dumping ground in the form of a pile. In its vicinity, processes of acid drainage have developed as a result of contamination of soils and groundwater. Geochemical transformations of mineral contents of waste can significantly affect physical and chemical properties of the soils and the bedrock. At the prospect of termination of the mining activity in the near future, determining the routes of the pollution migration, ability to monitor acid drainage processes and assessment of the risk of heavy metal pollution are really crucial. The paper presents a proposal for solving this problem by means of geophysical methods: Electrical Resistivity Tomography (ERT), Time Domain-Induced Polarisation (TDIP), Frequency Domain Electromagnetics (FDEM) and shallow-depth magnetometric surveys combined with geochemical investigations. The obtained results of geophysical surveys have been confirmed by geochemical investigations. The applied ERT and TDIP methods make it possible to identify the spread of the zones of pollution around the tailing pile, but their effectiveness depends on humidity of the ground. Soil magnetometry and shallow-depth induction profiling are a good tool to identify the medium contaminated with minerals redeposited by aeolian processes and allow to determine the range of the dust spread from the pile. It has been shown that the range of impact of the geochemical changes around the tailing pile is high and depends not only on directions and dynamics of water flow from the pile but also on aeolian transport.

Combination of different geophysical techniques for the location of historical waste in the Izery Mountains (SW Poland).

An initial magnetic survey conducted on the soil surface in the Orle forest glade, located in the Izery Mountains (south-western Poland), indicated the existence of a strong magnetic anomaly. Most cores collected in the glade outside the area of magnetic anomaly show a vertical distribution of magnetic susceptibility typical for soils formed on a diamagnetic or paramagnetic background, in unpolluted areas and influenced only by natural processes. The different patterns of magnetic susceptibility values exhibited by cores collected in the area of the magnetic anomaly reveal the source of the magnetic signal as an anthropogenic layer of waste buried in the subsoil, which was dumped in this area during the historical activity of a glass factory that was active in Orle in the 18th and 19th centuries. Topsoil measurements of magnetic susceptibility revealed that this anthropogenic material has completely different magnetic properties than the natural geological background, therefore making possible the use of magnetic and geoelectrical techniques to determine the location of buried historical waste. Application of different magnetic and geoelectrical methods (soil magnetometry, magnetic gradiometry, EM profiling, electrical resistivity tomography), in combination with a previous magnetic survey, enabled assessment of the location, depth and thickness of the anthropogenic layer. The anthropogenic layer consisted of historical slags and ashes from glass production mixed with modern bottom ashes and construction waste dumped here during the second part of the 20th century. The anthropogenic material occurs in the form of a nonhomogeneous layer characterized by high magnetic susceptibility (>100 × 10-5 SI units) and low resistivity (<200 Ωm) as well as high and variable apparent conductivity (>25 mS/m). These properties are firmly different from the properties of the natural soil and parent rocks and enable fairly precise location of the anthropogenic layer using magnetic and geoelectrical measurements.