(WELL) (Hydraulics) The watertight seal established in the annular space between the outermost water well casing and the drill hole to prevent the inflow and movement of surface water or shallow ground water, or to prevent the outflow or movement of water under artesian pressures. The term also includes a Sanitary Seal.
SEAL
Meaning of SEAL in English
Environmental engineering English vocabulary. Английский словарь экологического инжиниринга. 2012