EJECTOR WELL

In a typical eductor well system a series of wells are installed with a spacing related to the soil condition. The well are equipped with a feed pipe, a venturi ejector and a return pipe. At the head of the well, the feed pipe is connected to a high pressure feed line and the return pipe is connected to a low pressure evacuation line. The two lines are connected to a special pumping plant which supply the feed line with high pressure water and collect and evacuate the water from the evacuation line. The high pressure water going through the venturi will ÇsuccionÈ the ground water and push it up to surface through the return pipe. This system can lower the water table to or Ð 100 ft. It is where the permeability of soil is low.

INSTALLATION

Despite higher installation cost, wells are being used more and more because they often prove more economical to operate than wellpoints. Well can be installed at ground surface outside the construction area and will lower water in a single lift without staging. Units are spaced (6to 60m) on centers. Each unit comprises a well, pump, and discharge piping. Educators are intalled at relatively close spacing similar to the array in wellpoint systems, but requires only a single stage to effect drawdowns up to 100 feets (30m). However, because the educator system is very power inefficient, its use generally is limited to soil of low permeability.