Abstract: A wellpoint pumping system having a frame and a positive displacement rotary pump for pumping air, water or a mixture thereof mounted on the frame. The pump has two rotors with intermeshing lobes mounted on horizontal and parallel shafts, an inlet port below the rotors and an outlet port above the rotors. A motor for driving the rotors is mounted on the frame and a coupler connects the motor to the rotors. A closed inlet reservoir is formed in the frame below the pump, and an outlet reservoir is mounted on the frame at a level above the inlet reservoir. A conduit depends from the pump inlet port into the inlet reservoir and terminates close to the bottom of the inlet reservoir and a conduit connects the outlet port of the pump with the outlet reservoir.