Quasi 3D model construction of artificial recharge through the vadose zone using time-lapse zero-offset profiling of cross borehole radar

Hydrologic processes in the vadose zone were studied by using a time-laps geophysical methodology. Main focus was on using the acquired geophysical data to inversely estimate the soil water retention and unsaturated hydraulic conductivity functions. The soil hydraulic properties were estimated from cross borehole radar data obtained during a ground water recharge test in a infiltration pit. We used the HYDRUS-2D software package for the inverse parameter estimation problem. The estimated soil hydraulic parameters were subsequently employed in a forward simulation to construct a quasi three-dimensional image of the variably-saturated flow process in the vadose zone.