الفهرس 
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Abstract
SUMMARY and CONCLUSION
The objective of the present thesis is to discuss the major chemistry of surface water, soil and Nile sediments of El Tebbin area. Water quality assessment and pollution level of Soil and Nile sediments are discussed through comparing of the evaluated results with the national and international standard limits as well as numerical methods. In this study, we gave a special attention to the binding of some heavy metals to the main fractions in soils, using five-step sequential extraction procedures.
El-Tebbin area is located about 20 Km south of Cairo, directly east of the River Nile. It extends between longitudes (31° 17̀ - 31° 21̀ E) and latitudes (29° 45̀-29° 48̀ N) it can be divided into three regions, a domestic region, an industrial region and agricultural farms. Geologically it consists of Quaternary deposits and flood plain sediments of the Nile River.
The main findings and conclusions obtained from the present study are summarized in the following:
A- Water:
1. TDS values indicated that, surface water of El Tebbin area range from fresh water to brackish water; following the order El Hager Canal > El Khashab Canal > El Tarkhaniya Canal > River Nile. Generally El Tebbin Surface water area shows no heavy metals pollution. Among nine analyzed heavy metals, Surface water at the study area shows no heavy metals pollution, just Sample No. 11 at El Hager canal is polluted with Iron. This may be attributed to the presence of ferrous metallurgical works and other industrial activities.
2. Surface water ranges between moderately and very hard class for laundry usage and from permissible to poor classes for domestic purposes, the water can be used under special conditions.
3. Concerning use of Nile water for drinking purposes, physicochemical Parameters, examined heavy metals and major ions were in the optimum range of WHO (2011), except bicarbonate concentrations were in an alarming state, this is fit with WQI calculation that Nile water is better for drinking purposes after simple treatment. Almost all three water canals exceed the limits for chloride, sulfate, sodium, potassium and calcium, regarding drinking purpose, WQI indicated the unfit of this canals water for drinking until primary treatment. The suitability of water for irrigation is evaluated based on SAR, EC results, US Salinity diagram and WQI, the Nile water was found to be excellent for irrigation while the canals water is good for many types of crops with minor degree of threat. All water samples require treatment for specific industries according to WQI values.
4. Factor analysis slightly referred to impact of temperature and some chemical constituents on chemistry of water.
B- Soil:
1. Apart from Co, Ni besides few samples polluted with Zn, Pb, Cd and Cu, the study area show no heavy metals pollution.
2. Generally, spatial distribution of pH, EC and CaCO3 for soil showed that the highest values are recorded eastward. Soil organic matter shows the highest values at the central pats of El Tebbin area with dense agricultural activities. Spatial distribution also classified the investigated area according to their potentiality into two Heavy metals groups:
a. Low potential concentration group including Zn, Cd, Pb, Cu and Cr.
b. Considerable concentrations potential group is represented by Co and Ni.
3. Four factor analyses (FA) were defined, pH factor, geogenic factor, clay factor and anthropogenic factor.
4. The calculated single pollution indices recorded that, investigated soil samples were varied from uncontaminated to very high contaminated. The calculated integrated pollution indices showed that, about 60% of the study area show considerable contamination values, followed by very high contaminated pattern according to contamination degree (DC) results. Drastic rectification measures are not needed according to Pollution load index (PLI) results.
C- Nile sediments:
1. Generally physiochemical parameters as well as heavy metals area depleted in most of river bank sediments comparing with soil samples, this is controlled by two factors; the textural characteristics and the anthropogenic influence. Soil is finer and more subjected to anthropogenic activities.
2. River bank sediments show no heavy metals contamination; all concentrations are lower than or flocculated within standard permissible limits.
3. Pollution indices indicated that, the Nile sediment uncontaminated and needn’t to drastic rectification measures.
D- Soil speciation:
speciation results showed that, the residual fraction is the most dominate one, these metals are enclosed in the crystal lattices of minerals with strong bindings consequently are unlikely to be released to the environment, they are generally neither have bioavailability nor effect on the environment. The metals like Cd, Zn, Cu, Pb (in few sample numbers) and Fe represent appreciable portions in non-resistant fractions (exchangeable, carbonate, organic, and reducible), under favorable conditions they can be released to pollute the environment.
The average potential mobility of the metals in the soil samples studied arranged in decreasing order as follows: Cd > Zn > Pb > Cu > Fe > Ni > Co. Risk assessment code (RAC) indicated that, all studied samples fall in low risk category (1-10%), except sample No. 25 fall in medium risk category recording RAC% of 27.8 for Zn metal.