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Gaza Project (II) 2006-2009
Geochemical characterization of groundwater and the potential reuse of sludge and treated wastewater in the agricultural sector of the Gaza Strip Currently, about 60-80% of the domestic wastewater is discharged into the environment without treatment, either directly at the source, after collection from cesspits, or through the effluent of the sewer system or the overloaded treatment plants. Assuming that 60% of the water used for domestic usage comes back as wastewater, One of the key recommendations of the project “Monitoring of Groundwater and soil pollution levels in Gaza Strip” was that the treated wastewater is a promising water resource for agriculture, and regular monitoring systems on soil, crops and groundwater should be adopted. Up to now there has been very little production of sludge as all existing wastewater treatment plants are deficient and operating with old technologies. The construction of new wastewater treatment plants or the rehabilitation of the existing ones in To guarantee and safeguard hygienic standards and have no adverse effects on the human health, environmental quality must be given the highest priority. Although opponents of sludge use have many reservations, one of their main concerns is the long-term buildup of heavy metals in the soil. Over time, metals such as cadmium, zinc, and copper could build up to levels high enough to damage agricultural soils. Although the use of sludge on agricultural land is largely dictated by nutrient content (N and P), the accumulation of potentially toxic elements in sewage sludge is an important aspect of sludge quality, which should be considered in terms of long-term sustainable use of sludge on land. The most important nutrients in the sludge are nitrogen, phosphorus, and potassium. Other nutrients that may be present include calcium, magnesium, sulfur and they add copper even though it is considered as a heavy metal. According to the American standards of sludge used in agriculture, the average concentration of N and P in dry weight is 2% and <1% respectively; while the total solids are 3.4%. Although sludge is a valuable source of plant nutrients, the nutrient concentrations are significantly lower than most commercial fertilizers. It has been suggested that determination of adsorbable organic halogens (AOX) be used as an indicator for these priority substances. Moreover, AOX determination is a relatively easy technique to use. Because AOX is an analytical parameter and represents a wide range of substances, differing not only in their chemical structure but also in their toxicological profile, a description of relevant toxicological endpoints cannot be given. Several points are still suspended and need further research and investigation. Examples of these points are: the main sources of high Zn and AOX in the sludge; how and when exactly the Zn and AOX are build in the treatment process, origin and fate of Nitrate in Groundwater and wastewater; in addition to total metal concentrations the determination of specific chemical forms of heavy metals and their mode of binding in soil is very important in order to estimate their mobility, bioavailability and related ecotoxicity; education, information, and training of farmers also play an important role in promoting sensible reuse practices; by the reuse of treated wastewater, Gaza can not only reduce the pollution load of the Mediterranean Sea by wastewater contaminants but also consider wastewater as a precious source of water which could be used in agriculture.
Direct purposeTo carry on… the monitoring program and to establish a regional research methodology for potential reuse of wastewater and sludge achieving maximal use of wastewater, environmental protection, and to develop schemes and regimes of reuse based on socio-economic aspects of the region.
Objectives
1. To evaluate the environmental quality (groundwater, wastewater, sludge and soil) in the middle and south areas of the Gaza Strip. The project tries to reduce the dose of suffering of the people in the troubling area and we hope that the recent evacuation of the Israeli settlements in the region (which used to occupy more than 40% of the region) might open better horizons. 2. To study the sources and the buildup mechanism of the adsorbable organic halogens (AOX) in the wastewater and sludge of the Gaza Strip. 3. To study the sources and the buildup mechanism of the zinc (Zn) in the wastewater and sludge of the Gaza Strip. 4. To identify the major sources of nitrate (NO3) in the groundwater of the Gaza Strip by using N and O isotopes. 5. To introduce a scientific method for nitrate removal from groundwater and to simulate a computer model for NO3 removal. 6. To establish a pilot study for wastewater and sludge reuse beside 7. To highlight the various options that aim to reuse the treated wastewater and sludge in the Gaza Strip in a manner that will ensure agriculturally sustainable development. 8. To develop a concrete database for some important environmental themes, such as water quality, wastewater characteristics, the quality of soil and sludge and finally the characteristics of solid waste leachate in the Gaza Strip. General ApproachThe project will be academic oriented in full coordination with the Governorate of Gaza and the MSc program in the Faculty of Engineering at the Islamic University of Gaza. The objectives of the project will be formulated in research topic and each topic will be extended to a full research proposal which will be given to one MSc student or more.
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