Vacuum extraction apparatus and process

A method for multi-phase vacuum extraction, comprising:

• providing an apparatus comprising:
• a first substantially vertically oriented conduit having an upper end portion and a lower end portion, said upper end portion including a vacuum suction port, wherein said first substantially vertically oriented conduit has sidewalls which define an inner surface at the upper end portion of said first substantially vertically oriented conduit;
• a second substantially vertically oriented conduit having an open upper end portion and a lower end portion, said lower end portion having plural openings spaced from the lowest point to the highest point thereof, wherein said second substantially vertically oriented conduit has sidewalls which define an outer surface at the upper end portion of said second substantially vertically oriented conduit;
• wherein said plural openings are characterized by cross-sectional flow area which is gradated to increase from the lowest point to the highest point of said lower end portion;
• and wherein said second substantially vertically oriented conduit is axially disposed within said first substantially vertically oriented conduit;
• a seal disposed between the outer surface of the upper end portion of said second substantially vertically oriented conduit, and the inner surface of the upper end portion of said first substantially vertically oriented conduit below said vacuum suction port;
• and
• a gas inlet port disposed in said first substantially vertically oriented conduit below an elevation level of said seal;
• positioning said end portion of said second substantially vertically oriented conduit through a level of liquid between said highest point and said lowest point;
• and,
• drawing a vacuum on said vacuum suction port sufficient to withdraw a multi-phase effluent from said vacuum suction port.

An apparatus for removing contaminants from a contaminated area of a subsurface comprising:

• a riser pipe extending downwardly from the surface and having a perforated lower portion;
• a drop tube located within said riser pipe, said drop tube having a lower portion having an open end and having perforations, and having an upper open end;
• a movable seal,
• wherein said drop tube is held within said riser pipe by said movable seal to be movable along a longitudinal axis of the drop tube, wherein said movable seal separates a first atmosphere of the riser pipe below said movable seal from a second atmosphere of the riser pipe above said movable seal;
• said riser pipe having an inlet for feeding entrainment gas to the first atmosphere of said riser pipe;
• said riser pipe having an outlet for drawing a vacuum from said second atmosphere of said riser pipe;
• and
• a vacuum forming apparatus in fluid communication with the riser pipe outlet, the upper portion of riser pipe in fluid communication with the drop tube upper end, and adapted to form a zone of reduced pressure in the subsurface around the riser pipe below the movable seal,
• whereby gases and liquid are drawable from the subsurface into the riser pipe below the movable seal and into the drop tube and conveyed to the surface as a common stream, said drawn gases including those in the contaminated area and entrainment gas.