EVOLUTION SPATIO-TEMPORELLE DE LA PHYSICO-CHIMIE, MICROBIOLOGIE ET ÉCOTOXICOLOGIE DES LIXIVIATS DE LA DÉCHARGE PUBLIQUE D’EL-KERMA (ORAN, ALGÉRIE)

Abstract

This work is part of the rehabilitation of landfills. Indeed, the dump of El Kerma (Oran, Algeria) is the central storage facility and disposal of solid waste (domestic, industrial, hospital and other) of the city of Oran. Huge quantities of waste discharged into the landfill, generate highly polluting leachate waters, rich in organic matter (average COD = 14,000 mg O2 / l), salt (mean EC = 130 mS / cm) and micro organisms. The physicochemical characterization of raw leachate generated by the landfill showed that these juices and stabilized discharge old, carrying a large pollution load (BOD5/COD = 0.052). The compositional analysis of heavy metals showed the significant metal loading of these effluents, in which iron is the most abundant metal (8 mg / l). The results of the bacteriological characterization indicated a very poor microbiological quality of the leachate. Indeed, rates of over 18,000 organisms per 100 ml of leachate were recorded for total coliforms and fecal streptococci, considered as tracers of the first rank of microbial pollution in the juice of landfills. Trials of acute ecotoxicity test Toxtracer made on these leachates showed a very high inhibition rate, exceeding 50% for dilutions greater than or equal to 0.5. This makes these effluents extremely toxic and thus presents a continuous danger to the health of local population and surrounding environment. Therefore, these wastes require a specific treatment prior to discharge into the receiving landfills.