Abstract: A method and system for collecting and containing leachate from a landfill uses a submerged drainage sink to develop a flow pattern towards the drainage sink contained within a containment zone, and therefore minimizes the chance of contaminating area groundwater. In a first embodiment of the invention for use in a substantially flat area, a perimeter barrier wall is provided and extends downward into a bottom barrier layer, such as an aquitard, a clay layer, or a synthetic material. The barrier wall and the bottom barrier layer define a containment zone containing the drainage sink, which is disposed below the groundwater level. Leachate and groundwater are permitted to mix within the sink. The desired flow pattern towards the drainage sink is induced by collecting and removing the leachate/groundwater mixture from the drainage sink to lower the leachate level in the drainage sink to a level which is below the groundwater level outside of the wall and below the piezometric level below the sink.