Groundwater Quality in the Vicinity of an Abandoned Mining Site – The M'fis Mine, Southeast of Morocco

Abstract

The diagnosis of the current state of the environment (groundwater quality and tailings composition) was carried out in the vicinity of the M'fis mine (Southeast of Morocco) in order to evaluate the impact of mine tailings on groundwater.Water samples from the well in the center of the mine site and from other nearby wells were collected and analyzed.In addition, the characterization of the tailings shows the presence of sulfides and other chemical elements, constituting the main source of pollution.In turn, the results of geochemical analyses show that groundwater is characterized by low levels of metals, despite the presence of these pollutants in the tailings and in the waste rock piles.The concentrations of metallic trace elements in well groundwater, slightly exceeding the standards of potability (the WHO standard), remain acceptable for irrigation and for livestock.These results can be explained by the carbonate geological formation, constituting the transfer medium of the pollutants towards the aquifer and also by the weak circulation of the metal ions under the desert climate which prevent dissolution and infiltration.