Khalil A., Hanich L., Hakkou R., Lepage Michel. (2014). GIS-based environmental database for assessing the mine pollution : a case study of an abandoned mine site in Morocco. Journal of Geochemical Exploration, 144 (SI), p. 468-477. ISSN 0375-6742.
Titre du document
GIS-based environmental database for assessing the mine pollution : a case study of an abandoned mine site in Morocco
Journal of Geochemical Exploration, 2014,
144 (SI), p. 468-477 ISSN 0375-6742
Morocco with important mining activities is increasingly concerned about impacts of mining on the environment. In Morocco, there are approximately 200 abandoned mine sites which vary from small scale underground mines to large scale open-pit mines. Some of these mines, with reactive tailings and waste rocks, are problematic. Indeed, Acid Mine Drainage (AMD) pollution from abandoned mines is responsible for soil and water contamination, land resources degradation, changes in landscapes, habitat destruction and human health hazards. In the current case study about the abandoned Kettara mine site, the impact of the old mining activity is assessed by the design and elaboration of an environmental database which will be supported by Geographic Information System (GIS) technology. This database includes multidisciplinary data related to geochemistry, hydrochemistry, hydrology, land cover, geology and climates. The current research demonstrated the efficiency of integrating multidisciplinary data and using GIS technologies when assessing the environmental impact of abandoned mines and forecasting how the pollution is occurred. The obtained results show that in addition to the soil, the surface water and groundwater of the Kettara mine are also contaminated by pollutants which were previously released from mine wastes by AMD action. The sulphate content and the Electrical Conductivity (EC) of the surface water and groundwater are high. The average values for surface water are: sulphate approximate to 7920 mg/L and EC approximate to 256851 mu S/cm. However, in groundwater they are: sulphate approximate to 2088 mg/L and EC approximate to 631 mu S/cm. These values exceed the guidelines for drinking water quality prescribed by the World Health Organization (WHO) 600 mg/L and 1500 mu S/cm for sulphate and EC respectively. The developed GIS based environmental database will serve as a reference study for other abandoned mine sites. Finally, it will be employed for the establishment of a web-based GIS Decision Support System which will assist decision makers in assessing and monitoring the occurred mine pollution.
