Assessment of Heavy Metals Contamination in Spoil Heaps of Ain Aouda Mine (Taza, Morocco)

The purpose of this study is to evaluate the level of heavy metal contamination in the spoil heaps of the former Ain Aouda mine (Taza). In this regard, solid samples of the study area were sampled. The set of analyses carried out have detected the presence of zinc (Zn), lead (Pb), copper (Cu), arsenic (As) and nickel (Ni) that remain in these metal discharges. The calculation of contamination/pollution indices: the Geo Accumulation Index (Igeo), the Enrichment Factor (EF) and the Pollution Index (IP) were used to predict the extent of heavy metal contamination. The results of this study suggest that the spoil heaps reveal polymetallic contaminations allowing the trace metal elements to be classified in the following order Zn ˃ Pb ˃ As ˃ Cu > Ni. Knowing well that the alteration and erosion of this stock of mine waste could contribute to the degradation of the natural environment by these elements that are present.