Remediation of Leachate Contaminated Groundwater in Unconfined Aquifer by MSL System

The multiple-soil-layer system (MSL) used in this study consisted of blocks of mixture of clay, sawdust and granular iron. Zeolite was used as an intermediate layer. Aeration was done with the aeration to non-aeration period ratio of 4 and 8 hr. The influent and effluent were analyzed twice a week for pH, conductivity, COD, BOD, TKN, NH3-N and TP. Two sets of the experiments with various hydraulic loading rates were conducted in this study. The 1st set consisted of 3 hydraulic loadings at 0.1, 0.3 and 0.5 m3/(m2 x d) while the 2nd set consisted of 3 hydraulic loadings at the rate from the 1st run that gave the highest removal efficiencies and ± 0.05 m3/(m2 x d). The results of the 1st experiment show that the hydraulic loadings at 0.1 m3/(m2 x d) gave the maximum removal efficiencies. The removal rates of COD, BOD, TN, NH3-N and TP were 19.1 %, 97.9 %, 37.1 %, 99.2 % and 46.8, respectively. The results of the 2nd experiment show that the hydraulic loadings at 0.05 m3/(m2 x d) gave the maximum removal efficiencies. The removal rates of COD, BOD, TN, NH3-N and TP were 22.1 %, 99.2 %, 88.5 %, 99.5 % and 78.5 %, respectively.