Volume XXII |

Evaluation of water contamination in a crossborder river catchment affected by mining activities (a case study between Republics of Serbia and Bulgaria)

Abstract: The current article aims to evaluate water contamination in the crossborder section of the Timok River in terms of metalloids and heavy metals. Water pollution comes due to the unregulated discharges of untreated effluents from the Bor mining area (Eastern Serbia) and surrounding ore-smelting plants, dressing and processing factories. Input data includes information concerning the values of eight chemical parameters (As, Cd, Cu, Fe, Mn, Ni, Pb, and Zn), measured at one water sampling site from 2015 until 2020. The analysis follows the Environmental Quality Standards (EQS) for priority substances and some other pollutants recommended in Directive 2013/39/EC and their equivalent criteria transposed into Ordinance H-4/2012. The Heavy Metal Pollution Indеx (HPI) to assess the suitability of water resources for various human needs is calculated. Results obtained show the content of Cd, Cu, Fe, Mn, Ni, and Zn does not fulfill the EQS. The contamination with Cd and Cu is the most severe, the highest concentrations exceeding the normatively determined standards by more than 20 times. The HPI achieves scores ranging from 200.58 (2015) up to 1163.65 (2019), indicating “High pollution” and suggesting the water resources are inappropriate for human consumption. This work complements past studies with findings for a recent period.