Identification of pollution sources in closed mining sites with an Impact on the quality of surface water in the Brad area

Pollution caused by closed mining activities is particularly difficult to treat because it dates back a very long time. Water contamination results from large-scale disturbance of the land on which the underground exploitation of the useful mineral substance took place. Discharges from underground mines can be treated as diffuse point sources; water quality is due to reactions that occur in an area that can cover tens of square kilometres. The main sources are groundwater, which increases after the pumping is stopped, and tailings stored in dumps and tailings ponds. When the mine closes, the pumps are stopped and the groundwater level rises until it reaches the surface or discharges into the aquifers above. Although discharges from wells and galleries are often the most visible sources, surface activities such as mineral processing, tailings and waste disposal are also a significant source of pollution. The river is located on the Barza gold-silver ore mining operation took place. The runoff waters present in this perimeter can transport contaminated sediments, where the tailings dumps are washed away by precipitation. The paper aims to identify the sources of surface water pollution in the Barza closed mining site that influences the quality of surface water