. "zone of saturation"^^ . . "ENVO"^^ . "A zone beneath the land surface in which all interstices are filled with water. Water in the phreatic zone has a hydraulic head greater than atmospheric pressure due to the weight of overlying groundwater."^^ . "Wikipedia:Phreatic_zone"^^ . "phreatic zone"^^ . "ENVO:00000329"^^ .