الفهرس 
AcknowledgementOnly 14 pages are availabe for public view
 |  | from | 16 |  |  |
| | | from | 16 | | |
Abstract
Alexandria metropolitan area represents a case of unique and hi~h concentration of industry mixed with increasin~ number of population. For the master plan, the collection of industrial waste with the domestic waste and their treatment is recommended a head of their final discharge ei ther on land for agriculture purpose or to the sea. The aim of the present stud y was to assess Alexandria sewage toxicity on either plant or fish, to assess the toxicity removals achieved by treatments of waste. and to test the bioassay techniques for the validity and sensitivity in the toxicity asses smen t . The current s ituat ion of sewage drainage in Alexandria city was described through many formal and informal communications with the personnel working in Alexandria General Organization for Sanitary Drain age as regards the different pump stations, and types of waste in each as well as the treatment activities done. The existing sewerage system includes about 38 ma in pump stations of various capacities, and the East and West sewage treatment plants. The Eas t plant performance is not as designed while the West plant is still under construction. The various sources of wastewaters include, domestic waste, industrial wastes from the various industries located in the city, in addition to the unestimated sources of wastes from public services and small scale trades. This combined waste is being discharged without treatment to the local receiving waters through (a) Kai t Bay p. s . , (b) lake Maryout, and (c) some agricultural drains located in the East and South of the city. beach Other minor outfalls are located along the for the sake of disposal of rain water over flow during winter season. Characterization for the effluents of the 9 selected stations was determined to give a real image of the constituents of wastewaters. Certain parameters were selected for this purpose. The results showed variations in the composition of the different wastes. However- 1 L were characterized by high strength as indicated by the pollution loads that ranged from 298-1380 mg!l COD,164-80& mg!l BOD, and 170-1997 mg!l suspended sol ids. Nearly all parameters, except for N03,dissolved solids (D.S) and heavy metals ,for the different wastes, showed higher values than the standard values set by the Egyptian law. Moharram 1/1. Bay Industrial Complex effluent showed highest values 0 f many parameters; BOD (806 mg/l), colour (1058 p.c.s.unit) ,S04 (439 mg/l) Cl(3l46 mg/l), and settle able solids (s8ml/l after one hour settling). On the other hand, Maamoura p.s. waste showed the lowest values of nearly all parameters. No.2-west p.s. waste showed the highest values of solids, grease and oils. Biological treatment, using activated sludge applied process, and sand filtration treatment were on the raw effluents of the East and West zones of the city. Biological treatment induced partial removal of BOD, COD,S.S. detergents, NH3 and H2S. However, the values of most of these parameters in the biologically treated effluents exceeded the standard val ues set by the law. After B. T ., BOD val ues were reduced to be about twice the standard value, and COD val ue were about 3 times, whi le suspended sol ids (S.S) value -- was-about- 5 times - the standard value. The incomplete removal of organic matter by B.T. was attributed to the upset conditions from organic and toxic shock loading, resulting from industrial waste discharge, such as polychlorinated as well aromatic bi~’phenyl s, halogenated pesticides, as and hydrocarbons. Biotoxicity of the raw effluents of the selected 9 stations as well as the two stages treated effluents (B. T. and S. F . treatment) of both the East and West zones of was Root the city, evaluated: elongation bioassay technique, using 3 different seeds; beans, maize, and helba, was applied. The toxic effect of the effluents indicated by inhibitory the effect was on the root elongation process. EC50 was estimated. Fi sh bioas say technique was also applied using the fries of Mu~il cephalus. Toxicity effect was determined by fish mortality as well as changes in fish behaviour. Both tcso and estimated. seeds and Both L T50 were fish were exposed effluents. serial dilutions of different to The di fferent raw wastes were highly toxic as shown by fish from high mortalities, which ranged 100