Interrelation between leachate and eluate

Leachate is one of the most important environmental problems generated at open dumps and sanitary landfills all over the world. Leaching of various pollutants within the solid waste body results in the pollution of the ground and surface waters. Therefore the leachate must be treated before discharged into the environment. In order to determine the most appropriate method of treatment, the amount and the characteristics of the leachate to be treated must be known. The most efficient data is the one collected after the leachate starts leaching out at the open dumps and sanitary landfills, which is obviously a late determination for deciding on the treatment method; because during this period the damage on the environment will already be in effect. To overcome this data problem, the characteristics of the eluates, representing the leachate characteristics, which are obtained from the same wastes to be landfilled, can be used as the data source. In the research conducted, the interrelation between the leachate and eluates obtained by different methods was determined. The purpose of this research was to determine the optimum method yielding the eluates resembling the leachate generated from the same solid waste. Two reactors filled with solid waste, simulating to a certain extent the sanitary landfill conditions, were used for the generation of leachate. Eluates from the same solid waste, that was filled in the reactors, were produced by different methods - Standard Leaching Test (SLT), International Unit Conversion System (IUCS) 48 Hours Shaking Test, Minnesota Test and DIN 38414-S4 Test. Then both the leachate generated in the reactors and the eluates obtained were analyzed for pH, biological oxygen demand (BOD), chemical oxygen demand (COD), 11 metals and inorganic elements and the results obtained were compared. The results showed that the SLT third day eluation yields the eluate having the closest values to the characteristics of the leachate generated at the reactors.