Assessment of groundwater potential and pollution risk using mathematical modeling case of Gash basin, Kassala Area
Dissertant
Thesis advisor
University
Omdurman Islamic University
Faculty
Unesco Chair in Water Resources
University Country
Sudan
Degree
Ph.D.
Degree Date
2009
English Abstract
This study has been carried out in the Kassala area which is situated between latitudes 15° 31''-15° 20.3'' north and longitudes 36° 14''-36° 32'' east covering an area of 232 Km2 in Eastern Sudan .It is typically a semi arid area with an annual rain fall of 247mm.
the purpose of this study is to predict the behavior of the hydraulic system of the Gash aquifer towards groundwater abstraction by using numerical models.
The study also deals with the general hydrogeology of the Kassala area and the sources and magnitude of pollution .Both field and laboratory methods were carried out to achieve these objectives (several soft ware programs were employed) The main aquifer in the Kassala area is constituted by the alluvial sediments of the Gash River which are composed of fine to coarse grained sandy, gravelly deposits.
This aquifer is mainly under non confined conditions and the groundwater levels vary from 3mto25m below the land surface.
The groundwater movement is parallel to the Gash River toward the North West.
The permeability of the aquifer varies from moderate to high pending on the lithology of the aquifer.
The recharge of groundwater is mainly derived from the infiltration of the surface water of the Gash River during the flood season.
It is equal to 96 million cubic meters per year.
The total annual groundwater abstraction amounts to 108million cubic meters and groundwater storage is equal 384 million cubic meters.
Monitoring of the groundwater levels indicated a long decline trend during the last three decades .However there is state of partial hydrologic equilibrium in the last decade and the groundwater levels remained slightly stable The groundwater of the study area is characterized by a calcium carbonate water type with light to moderate hardness it is dominated by alkaline earth and weak acids.
The salinity is generally low but Wad shereifi, Northern Sawagi areas contain brackish groundwater. The groundwater of Kassala area is under saturated with anhydrite, aragonite, gypsum and fluorite.
It is slightly saturated with calcite and dolomite.
Such minerals occur in the aquifer sediment in the kanker and caliches deposits Groundwater modeling predicts that the designed abstraction rates of the city supply are not sustainable and it is expected that the decline of the water level in the pumped areas will continue and after 20 years of operation the expected drawdown will reach 3 m in the northern and the southern parts of the Kassala area.
It is expected that many wells will become dry with a significant decrease in the yield of the other wells because of the reduction in the saturated thickness. The modeling shows that after 20 years more Nitrate contamination zones will be encountered in the (western, northeastern and southeastern parts).
High concentration of NO3 (500mg / l) contaminants from the south can travel and eventually will reach the north (the north Sawagi area). Based on this study several recommendations are proposed to protect the Gash alluvial aquifer from depletion and pollution hazard
Main Subjects
Earth Sciences, Water and Environment
Topics
No. of Pages
161
Table of Contents
Table of contents.
Abstract.
Chapter One : Introduction.
Chapter Two : Geological and Structural Setting.
Chapter Three : Methodology.
Chapter Four : Hydrology and hydrogeology.
Chapter Five : Hydro chemical characteristics of the aquifer.
Chapter Six : Mathematical Modeling.
Chapter Seven : Conclusion and recommendations.
References.
American Psychological Association (APA)
Muhammad, Sayf al-Din Yusuf. (2009). Assessment of groundwater potential and pollution risk using mathematical modeling case of Gash basin, Kassala Area. (Master's theses Theses and Dissertations Master). Sudan
https://search.emarefa.net/detail/BIM-392613
Modern Language Association (MLA)
Muhammad, Sayf al-Din Yusuf. Assessment of groundwater potential and pollution risk using mathematical modeling case of Gash basin, Kassala Area. (Master's theses Theses and Dissertations Master). (2009).
https://search.emarefa.net/detail/BIM-392613
American Medical Association (AMA)
Muhammad, Sayf al-Din Yusuf. (2009). Assessment of groundwater potential and pollution risk using mathematical modeling case of Gash basin, Kassala Area. (Master's theses Theses and Dissertations Master). Sudan
https://search.emarefa.net/detail/BIM-392613
Language
English
Data Type
Arab Theses
Record ID
BIM-392613