Abstract: A sparging well borehole has a single pipe extending downwardly in it. The lower end of the pipe terminates in the saturated zone and has orifices for discharging pressurized gas, usually air, which is injected into the saturated zone to liberate volatiles. A layer of impervious material is in the bore hole above the orifices and the hole is filled to the top from above the impervious layer with a porous material. A dome is positioned at the upper end of the borehole with an opening in the dome over the borehole. The dome is connected to a vacuum source to cause the vapor that is produced in the saturated zone and that is induced to migrate through the vadose zone and permeate the porous material in the borehole to be accumulated in the negative pressure interior of the sealed dome and collected for treatment by way of a piping system.