Assessment of Soil Contamination by Mining Discharges in the Essouk River (Northeast Algeria)

Abstract

Soil pollution by heavy metals is a frequently encountered issue at many hazardous waste sites. Mining operations generate a significant volume of inert materials and waste, which are then deposited on the surface. The abandoned mine of Sidi Kambar could pose a major problem due to the potentially high concentrations of potentially toxic elements present in its discharges. To assess the level of soil contamination near the abandoned Pb-Zn mine in Sidi Kambar, heavy metal concentrations were determined in soil samples taken from the Essouk River. The results of the monitoring of the spatial evolution of metal trace elements (Zn, Pb, and Fe) during the month of February 2023 in the soil of this watercourse show that metal content is growing in the order: Pb > Zn > Fe. They also exhibit variations across the ten (10) study stations, ranging from 102.7 to 141.2 for Zn, 1918.8 to 3150.4 for Fe, and 115.5 to 134.5 for Pb. The degree and sources of contamination were determined by calculating metal contamination indices: the geoaccumulation index, the contamination factor, the degree of contamination, and the pollution load index. High levels of contamination have been observed around spills of mining waste, resulting in high levels of contamination. However, no cases of extremely high or ultra-high contamination were found in the mining fields of the studied area. Therefore, human activities could be the main factor in abandoned Pb/Zn mining areas.