Geochemical Assessment for Trace Metal Contamination of Mining Wastes of Fel and Its Environs in Adamawa Region (Cameroon)

Abstract

Mining waste due to gold exploitation has a great consequence for the environment and needs to be assessed where mining sites are developed for good sustainable environmental management because it is responsible for the release of massive amounts of hazardous metals. For this purpose, the diagnosis of the current state of the environment of the mining sites of Fel and its environs was carried out through physical and geochemical analysis to assess evidence of pollutant capacity. Physical analyses focus on the granulometry of wastes while geochemical analyses concern the assessment of the amount 10 Metallic trace elements (MTE) on 9 samples from three mining sites. The results of the granulometric analyses reveal heterogeneity and discontinuity in the sandy gravel texture of the waste. Geochemical analyses show that a fine fraction less than 80 μm presents the best geochemical result for all chemical elements. The geoenvironmental assessment of the wastes according to the Geoaccumulation Index (Igeomax=7,14), the Contamination Factor (CFmax=212,45), the Degree of Contamination (DCmax=252,86) and the Sediment Pollution Index (SPI), characterized by low polluted sediment (SPImax=4,07), made it possible to establish the high link between As and Sb with very high concentrations, thus extreme pollution of these elements in the mining waste of the study area, particularly in Foum, Mama Wassande and Fel. Strong to very strong positive correlations observed between As and Cu, Pb, Cd and Cr, suggest that these MTE originated from a common source of contamination. Therefore, these MTE should be assessed on groundwater to prevent and avoid or minimize their effect on human health in this environment.