Mathematical Modelling to Trace the Leachate Plume of the Municipal Landfill in Groundwater Environment

At outside, the landfill A in Japan contamination has been found. It has been believed that the leachate must leak out from the municipal landfill site. Therefore, simulation of the movement of leachate was carried out to understand the behavior of the plume at the landfill site. The plume movement was simulated by the three-dimensional solute transport coupled with groundwater flow under different assumptions such as faults, leachate collection pipe, sheet wall. Only advection and dispersion are included in the present paper. The finite difference method was used as the numerical method to solve the partial differential equations of groundwater flow and solute transport. The method of characteristics was applied to solve the advection term of mass transport equation. A valuable attempt of the present paper is to simulate the leakage of leachate. The paper demonstrated that the effect of the faults at the landfill site is the most important factor which controls the movement of the leachate to the outside. There is a possibility that the leachate plume may leak under the sheet wall to outside.