Geochemical Characterization of the Spoil Heaps of the Ain Aouda Mine and its Impact on the Soil (Morocco)

Abstract

The exploitation of the Ain Aouda zinc lead mine in the Tazekka massif (Morocco) has abandoned spoil heaps stored directly on a karstified carbonated ground, without any means of precaution. The heaps were exposed to the weather agents, such as water infiltration and air circulation, which would generate a real source of pollution for the ecosystem. This pollution will inevitably produce effluents that can be loaded with metals and metalloids, which will have a significant negative influence on the soil and the environment. In this regard, the objective of this study was to confirm the existence of contamination of soils by using the technique of atomic emission spectrometry with inductively coupled plasma, and of spoil heaps by X-ray diffractometry, which confirmed the contamination by zinc, arsenic, lead and copper. Their maximum concentrations are 19858.800 (ppm), 1280.700 (ppm), 495.750 (ppm), and 328.65 (ppm), respectively. Nevertheless, it was noted that the pH of the majority of soils always remains basic, due to the significant presence of carbonates, the majority of soils are calcareous (15% to 30%) to very calcareous (> 30%). It was noticed that the phenomenon of neutralization occurs.

Physicochemical and geochemical characteristics of Bouaazza’s mine embankments and river sediments (Taza province, Morocco)

“…The Kingdom has become more alarmed and aware of the negative impacts caused by the discharges left by mining activities, which is witnessed in the studies and articles done to highlight the hazards connected to current or previous mining actions [6][7][8][9][10], that generate acid mine drainage AMD [11].…”