[Impact of polymetallic mine (Zn, Pb, Cu) residues on surface water, sediments and soils at the vicinity (Marrakech, Morocco)].
Metal sulphide tailings present a potential risk for the environment because of their natural oxidability which leads to the production of acid mine drainage. The prospected site close to Marrakech includes zinc, lead and copper sulphide deposits. This site is located in an agricultural area near the Tensift River which is used for irrigation. In addition to the tailing leachates, underground mine waters are also discharged into the river. This represents a potential risk for the environment and human health. The aim of this study was to assess the tailings impact on surface water, sediments and soil qualities. Chemical analysis of surface water and sediments collected downstream of the mine revealed that, water and sediments present high concentrations of major ions and heavy metals. The analysis also revealed spatial as well as temporal changes in the chemical properties of the studied water and sediments. These changes are attributed to the rising phenomena. The soil near the mine presents high content of sulphate. Its Zn, Pb, Cu and Fe contents are respectively 38, 15, 11 and 1.6 times higher than non contaminated soils located far away from the site. The soil irrigated with underground mine waters shows concentrations of SO4(2-), Cu, Zn, Fe, Cd and Pb which are respectively 4, 10, 28, 2, 9 and 12 times higher than soils which are not irrigated with this mine water. This study also showed that there has been a change in the physicochemical characteristics of water and sediments in the sampling points downstream of the mine before its closure and after its activity renewal.
El Adnani
M
M
Univ. Cadi Ayyad, FSS, Dépt. Biol., Lab. d'Hydrobiologie, d'Ecotoxicologie et d'Assainissement BP/2390, Marrakech 40 000, Morocco.
Rodriguez-Maroto
J M
JM
Sbai
M L
ML
Loukili Idrissi
L
L
Nejmeddine
A
A
D004784:Environmental Monitoring; D005618:Fresh Water / Q000032:analysis; D019015:Geologic Sediments / Q000032:analysis; D007220:Industrial Waste; D019216:Metals, Heavy / Q000032:analysis*; D008906:Mining; D009018:Morocco; D012989:Soil Pollutants / Q000032:analysis*; D014874:Water Pollutants, Chemical / Q000032:analysis*
D007220:Industrial Waste; D019216:Metals, Heavy; D012989:Soil Pollutants; D014874:Water Pollutants, Chemical