Introduction

A common technique for reducing the seepage loss from a reservoir is to line the reservoir with a clay blanket. Alternately, a compacted cap layer near the ground surface can limit infiltration into underlying waste material. If the waste is coarser in nature relative to the cap material, a capillary break phenomenon often results.

The problem is challenging to analyze because of the sharp contrast in the saturated hydraulic conductivity of the compacted material and that of the underlying material. As well, the underlying material is often sandy, with a very steep hydraulic conductivity function that requires a robust, iterative numerical solution. 

The objective of this example is to compare the computed steady-state water transfer solutions completed in SEEP/W for fully unsaturated flow with a known solution. In addition, it will be shown that flow across a capillary