Study of the soil contamination degree in the area of the former mining plant Plumbum (Adrianópolis, PR) due to the disposal of mining waste

Abstract

The area of the former mining plant Plumbum, located in the city of Adrianopolis (Paraná) received mining wastes enriched with potentially toxic metals. These mining wastes were disposed directly on the ground without any previous treatment, being exposed to weathering processes until the year 2007, when such materials received thin soil coverage. Even with the coverage, mining waste in diverse places of the deposit are still exposed to weathering processes. Thus, the main objective of this research is to evaluate in an integrated manner, using geochemical and biological methods, the contamination degree of the soils where these wastes were disposed. To achieve this goal, samples of waste and soil will be analyzed. The mining waste will be characterized using mineralogical analysis, determination of physico-chemical parameters, solubilization test, leaching, toxicity, sequential extraction and pH variation. In soils, geological and geotechnical characterizations will be conducted to determine whether soil characteristics favor or not the retention of metals, as well as the determination of physico-chemical parameters, solubility tests, toxicity, sequential extraction and determination of bacteria in soil. With the results of this research, it is intended to better understand the toxicity degree and the release of metals from the wastes and their interaction with soil and the biota. This way, it will be possible to determine whether or not these metals are contaminating the soil, and whether they are available to the biota. (AU)