Assesment of the potential risk elements at metal post-mining spoil heaps

Abstract

Metallic minerals mining and smelting are connected with the environment degradation, including spoil heaps arising. Even after processing, spoil still contains high levels of the metals, metalloids as well as other potential risk elements and became a potential source of air, water and soil metalliferous contamination for dozens of years. Eastern Slovakia is well known for its mining history and presence of old mining excavation, yet the spoil heaps represent almost the third of them. Method: We surveyed potential risk elements, including metals and metalloids in the substratum from overall nine spoil heaps (study sites) within the metal post-mining areas of Krompachy (KR) and Zlatá Baňa (ZB), located in Eastern Slovakia. The paper deals with characterization of substratum metalliferous contamination, with lay emphasis on the environmentally most relevant pollutants. Results: At all study sites, iron and aluminium were in the highest content, at both localities, Fe exceeded permissible limits and background values almost 43-times. Overloading of permissible limits as well as background levels of arsenic, cadmium, lead and mercury was noticed too. Clustering indicates the identical origin of risk elements, since iron and aluminium are supposed to be purely lithogenic and the rest of them are in increased concentrations as a consequence of mining activities. Conclusions: On the basis of results obtained, both of the areas could be characterized as highly polluted by environmentally relevant elements including arsenic, cadmium, copper, lead and especially mercury, i.e. heavy metals and metalloids found to be highly toxic even at low concentrations.

Metallic minerals mining and smelting are connected with the environment degradation, including spoil heaps arising. Even after processing, spoil still contains high levels of the metals, metalloids as well as other potential risk elements and became a potential source of air, water and soil metalliferous contamination for dozens of years. Eastern Slovakia is well known for its mining history and presence of old mining excavation, yet the spoil heaps represent almost the third of them. Method: We surveyed potential risk elements, including metals and metalloids in the substratum from overall nine spoil heaps (study sites) within the metal post-mining areas of Krompachy (KR) and Zlatá Baňa (ZB), located in Eastern Slovakia. The paper deals with characterization of substratum metalliferous contamination, with lay emphasis on the environmentally most relevant pollutants. Results: At all study sites, iron and aluminium were in the highest content, at both localities, Fe exceeded permissible limits and background values almost 43-times. Overloading of permissible limits as well as background levels of arsenic, cadmium, lead and mercury was noticed too. Clustering indicates the identical origin of risk elements, since iron and aluminium are supposed to be purely lithogenic and the rest of them are in increased concentrations as a consequence of mining activities. Conclusions: On the basis of results obtained, both of the areas could be characterized as highly polluted by environmentally relevant elements including arsenic, cadmium, copper, lead and especially mercury, i.e. heavy metals and metalloids found to be highly toxic even at low concentrations.