Trace Metals Assessment in Soils and Sediments near the Abandoned Mine of “El Abed” Pb-Zn deposit – Northwestern Algeria

Abstract

El-Abed is one of the largest historical and abandoned mining operations for Pb–Zn deposits in northwestern Algeria, leaving large amounts of mining wastes accumulating under the influence of wind erosion. This study aims to verify the concentrations and sources of heavy metals for fifty-six (56) surface samples of environmental media (soil, sediments and mining residues).Chemical analyzes were performed using an optical emission spectrophotometer. A set of environmental quality indicators and multivariate statistical methods with geographic information system was obtained. In this study the mean values ​​of the concentrations of trace metals are: (As = 30,82), (Pb = 1219,27), (Zn = 2855,94), (Cu = 5,3),mg/Kg, and the order as following : Zn > Pb > As > Cu. Based on these results, all trace metals except Copper (Cu) bypassed the the Geochemical background value in the Earth's crust. The results of the multivariate census indicated that there is a strong relationship for pollution indicators for trace elements lead (Pb), zinc (Zn) and arsenic (As). This factors indicate that they are from human sources, and a weak relationship for pollution indicators for trace elements copper (Cu), which is a natural source. Using Geographic Information System and based on spatial distribution maps, many hotspots have been identified. All sampling sites indicate general pollution, poor site quality and environmental hazards.