The term phreatic's used in Earth sciences to refer to matters relating to ground water below the static water table (the word originates from the Greek phrear, phreat- meaning "well" or "spring"). The term phreatic surface's where the hydrostatic pressure of groundwater or soil moisture's atmospheric (or pressure head's zero). This surface normally coincides with the water table. The phreatic zone's the layer(s) of soil or rock below the water table in which voids are permanently saturated wit… (More on Phreatic)