Groundwater contamination has become increasingly prevalent in recent years, emerging as a major environmental issue. Effective groundwater management requires tools that can track and predict the movement and behaviour of contaminants within subsurface environments. There is an increasing reliance on using numerical groundwater modeling to predict fate and transport of contaminants as well as employing predictive simulations to anticipate concentrations of contaminants in groundwater in order to evaluate a remedial action. Soils are porous media and exhibit a heterogeneous, multi-scale architecture. Their non-linear material properties have a significant influence on the soil water dynamics, which poses difficulties for numerical models. This study examines the numerical approximations applied to model water flow within the variably saturated soil zone, and transport of particles through this unsaturated condition.