Three wells lying downstream of the Kirbet es-Samra sewage treatment plant (KS) waste stabilization ponds, and two wells lying upstream of them were monitored. Historic results over the two past decades were used in evaluating of KS effluent on the groundwater resources of the area. Prior to 1985, the downstream wells were of high quality, but later the water started to deteriorate. An increases in all parameters was encountered, although initially, the increase in certain parameters was mild and due to overpumping of the well water. Later this increase continued at a much higher rate, although the water table in the area by some 20m with a variety of indications showing domestic wastewater pollution effects. Groundwater measurements indicated a recharge mouth in the KS area and along Wadi Dhuleil. Hence, it can be deducted that a source of inferior water quality is recharging the groundwater and causing this increase in parameters. Since no source of pollution other than KS is encountered in the area, and because the parameters in the groundwater increase towards the KS and Wadi Dhuleil, it can be deducted that the effluent from KS is polluting the groundwater and rendering it unsuitable for almost all purposes. Comparatively, the two sample wells taken upstream of KS showed a mild increase in the water quality parameters until 1981-82, due to overpumping of the well water. But due to several wet years, the water table rose and these values decreased, continuing at a constant level. Since the groundwater flow is in the direction of Wadi Dhuleil, the negative effect of KS on groundwater resources can be clearly seen. If not stopped, this continuous manipulation of the groundwater resources will further pollute the groundwater resources of the entire area

A short historical review shows that treatment plants have been developed only after problems have occurred. The high diversity pollutants of totally different origins and natures, and chemical and biological characteristics require different tools. A good approach is to select one basic tool and try to integrate tools for other tasks within this main tool. The main tool will be in almost every case (for municipal wastewaters) an activated sludge plant surrounded by other elements of polishing or for the elimination of nitrogen, phosphorus, etc., according to the local situation. Some tasks like elimination of pathogens or eggs of intestinal worms, are automatically performed to a high degree in connection with the task of eliminating degradable organics. Special wastewaters with certain pollutants have to be treated at the place of their origins. For wastewater of agricultural production direct or indirect recycling should be favoured. For wastewater of industrial background containing toxicants, treatment must be economically included in the production process of the main product. Besides this, there appears a multitude of organics of unknown chemical composition and environmental significance. They should be permitted for public application only after lab tests have proved their degradability and the conditions of their degradation. Finally, one should always be aware that treatment plants have to be composed according to local conditions. Depending on the amount and composition of wastes, an integration of tool has to be found that not only meets the demands stemming from the wastewaters but also can be integrated into the existing economical and ecological frame