Abstract: Apparatus and method for sparging ground water by developing density driven convection and promoting the physical removal and biodegradation of contaminants. The method includes providing a well casing having two fluid permeable sidewalls separated by a fluid impermeable sidewall, and inserting the well casing into a generally vertical borehole so that the fluid permeable sidewalls are positioned below the water table. An injector tube is provided in the well casing so that a lower end thereof is located at the lower end of the well casing and below the level of ground water collected in the well casing. Gas under pressure is forced out the lower end of the injector tube and into the ground water collected in the well casing to cause the gas to carry water upwardly within the well casing and out the well casing through the uppermost fluid permeable sidewall.