Water movement through unsaturated soil above the water table (the vadose zone) involves air and water phases where hydraulic conductivity depends non-linearly on soil moisture content. Richards’ Equation governs 3D transient flow in unsaturated porous media by combining Darcy's Law with the continuity equation: $\frac{\partial \theta}{\partial t} = \nabla \cdot \left[ K(\psi) \cdot \nabla (\psi + z) \right]$ Where $\theta$ is volumetric soil moisture content, $t$ is time, $\psi$ is soil matric suction head $(\psi < 0),$ $z$ is vertical elevation, and $K(\psi)$ is unsaturated hydraulic conductivity. Soil water retention curves $(K(\psi)$ and $\theta(\psi))$ are mathematically described using Van Genuchten’s Model: $\Theta = \left[ 1 + (\alpha \cdot |\psi|)^n \right]^{-m}$ Where $\Theta = \frac{\theta - \theta_r}{\theta_s - \theta_r}$ is effective saturation, and $\alpha$, $n,$ $m$ are empirical soil pore-structure parameters $(m = 1 - 1/n).$ Accurate estimation of aquifer r...