Arrangement for cleaning contaminated ground water

DETAILED DESCRIPTION Accordingly, it is an object of the present invention to provide an arrangement of the above mentioned general type, which is a further improvement of the known arrangement of this type.
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 the passage extending through the separating wall has a shaft insert provided with a gas chamber which is limited by a nozzle body arranged under a water level in the region of the shaft insert, so that a gas such as for example fresh air is supplied in the gas chamber during generation of a negative pressure above the water level, and the circulating pump operates as a suction pump in the water aspiration region of the shaft at the shaft insert and supplies the gas into a water receiving chamber which starts underneath the gas chamber and extends out of the region above the gas chamber.
The arrangement designed in accordance with the present invention combines the features of the arrangements proposed in the patent application P 39 31 012.
4 and in the older German document DE-OS 36 25 488.
It provides the advantage that the cleaning arrangement is located in easily accessible upper well shaft region practically independent from the position of the ground water level in the ground, and the ground water cleaning is performed both by a negative pressure treatment and also by a filter cleaning.
With this arrangement not only volatile impurities in gaseous state can be removed, but also the impurities which are dissolved in the ground water can be removed as well.
The location of the cleaning arrangement in the upper well region is especially advantageous for servicing of the filter.
The shaft insert can be formed preferably as a hollow cylinder which opens upwardly and is provided downwardly with at least one ground water inlet opening, wherein the gas chamber with the nozzle body and the water receiving chamber can be arranged or formed inside the hollow cylinder