Assessment of the Concentration of Heavy Metals in a Municipal Solid Waste Dumpsite Leachate

Abstract

Although municipal solid waste landfills are an indispensable part of modern-day society, the presence of heavy metals in leachates from such pose a contamination threat to ground water and surface water, especially if the landfill is unlined. The assessment of physicochemical characteristic and heavy metals in an unlined landfill at Nekede, Nigeria were carried out. Leachate samples were collected from actual streams from different locations in the landfill and analyzed using standard analytical procedures. The results show that certain heavy metals contained in the leachate were above permissible limits of drinking water and waste water discharge standards set by international regulatory bodies. Mn, Zn, Cd, Cu, Hg, As, Ni and Pb were in concentration ranges of 0.16-0.93,1.12-7.34,0.02-0.05,0.15-1.62,0.16- 0.27, 0.15-0.20, 0.28-0.62 and 0.12-0.36mg/100g respectively, which are several multiples of the acceptable standards. In the light of the potential of this leachate to contaminate the surrounding surface and groundwater sources in the vicinity of the landfill, appropriate control measures should be taken by the concerned authorities to rehabilitate the landfill and also to continuously monitor the groundwater sources around the area in order to contain any contamination that might occur.