Impact of stabilized leachate residues from the uncontrolled landfill of Mohammedia city on the ''Oued El Maleh'' river and on the soil

The evaluation of pollution generated by residues of the uncontrolled landfill of mesbahiat of mohammedia city at the level of the river ''oued el maleh''(omr),nearby soil and puddles of leachate from their percolation in the soil,show that the river and the surrounding sheet are still threatened by non-biodegradable inorganic pollution despite the closure of this landfill more than six years ago. these leachate puddles have very high electrical conductivities ranging from 34600 to 40900 μs / cm and that obtained at the river is about 4610 μs / cm. these high values are due to the presence of high concentrations of mineral salts,k+,na+,mg2+,ca2+ responsible for salinity and hardness,and various metals with varied forms. the concentrations of these salts in the stabilized leachate,as well as the metals as,cd,cr,cu,ni,pb,zn,v,cr,mn and ni are higher than those of the river water. otherwise,aluminum concentrations are very high in the river water samples compared to the leachate samples. for the same landfill,the results obtained for the metals,compared with those obtained by some previous studies shows that the metallic pollution generated by these metals decreased after six years of the landfill closure. the high cod content (1200 to 7700 mg o2 / l) and the absence of bod in the leachate samples reflect the introduction of non-biodegradable into the puddles of leachate,as well as the removal of biodegradable organic pollutants as the original leachate percolates into the soil before reaching the river edges. the metal analysis of soil samples near and far from puddles indicates that the soil seems to be less contaminated by leachate residues. © 2017,university of mohammed premier oujda morocco