Arrangement for cleaning contaminated ground water

DETAILED DESCRIPTION Accordingly, it is an object of the present invention to provide an arrangement for cleaning contaminated ground water which has a simple construction and is simple to use.
In keeping with these objects and with others which will become apparent hereinafter, one feature of the present invention resides, briefly stated, in an arrangement for cleaning contaminated ground water, in which a tightly insertable partition is arranged under the ground water level in a water impermeable portion of the shaft wall located between the water permeable portions and has an opening for a throughgoing passage which forms a part of a flow path circulating pump arranged in the wall shaft and ends above the ground water level in the well shaft, and a filter is located in the region of the well shaft in the flow path of the pump.
When the arrangement is designed in accordance with the present invention, the cleaning is performed inside the built shaft.
Aspiration of the ground water outside of the shaft and its return through additional absorption is dispensed with.
Here the available drilled shafts can be referred to as long as they have at least locally a water permeable shaft wall above the ground water level.
The arrangement of the absorption and withdrawal wells one above the other in a shaft prevents lifting of the ground water in the surrounding area of the well shaft as in the case of conventional withdrawal wells.
Thereby the danger of structure sinking is avoided, which is observed in the vicinity of the withdrawal wells.
Moreover, the constant ground water level in the surrounding area of the well shaft guarantees a uniform flow of the ground water in all ground layers.
In contrast to this, in the case of the withdrawal wells higher speeds in the well shaft vicinity occur due to the sinking of the ground water level.
Therefore the ground water from ground layers which have high flow speed of water drives water from the layers with slower flow speed.
Slower flowing ground water is as a rule contaminated stronger than faster flowing ground water, so that the efficiency of filtering devices with separate shafts for absorption and withdrawal wells is low