Contamination of soils and groundwater is considered as one of the major environmental problems. So, water and contaminate movement through soil especially in layered soil should be studied thoroughly. This research aims to study the contamination movement in a layered soil considering; water table fluctuation and applying the theories of transfer and diffusion in the unsaturated case. Numerical model with GEOSLOP software was used for simulating the movement of the contaminant through both saturated and unsaturated layered soils.
The study shows that various physical properties of soil layers has a serious impact on the movement of the contaminants, also it shows that the order of layers has a effective role in the extent of the movement and concentration of leachate in the area surrounding the location of landfills in the case of unsaturated soil, while changes in the level of groundwater don't make any change that can be mentioned with the number and order of layers but leads to a small changes in concentration of leachate. Whereas steady saturated soil conditions did not affect by the order and number of layers on the movement of leachate, but it is effected by the change in ground water level ,the change including the concentration and extend of the contaminate movement.