GIS-based approach to investigate the vulnerability of the Amman – Zerqa groundwater basin to contamination

Dissertant

al-Rawabidah, Abd Allah Mustafa

Thesis advisor

al-Ansari, Nazir Abbas
al-Adamat, Rida

Comitee Members

al-Farajat, Muhammad
Awawidah, Muhib

University

Al albayt University

Faculty

Institute of Earth and Environmental Sciences

University Country

Jordan

Degree

Master

Degree Date

2007

English Abstract

The Amman-Zerqa Basin is considered as one of the most important hydrological basins in Jordan.

It is located in the transitional area between the high lands in the west and the desert in the east.

This is not only reflected in the climatological changes from wet to dry but also it is characterized by different land use patterns and also by large changes of habitat.

While the western hilly areas are relatively densely populated, the southeast of the basin is fully desert and almost without population.

However more than 60% of the population of Jordan (3,720,000 inhabitant, DOS 2003) are living inside this basin.

(OPTIMA, 2004).

Information about vulnerability of groundwater to contamination is essential to facilitate groundwater planning and management.

The vulnerability of shallow groundwater to contamination in Amman Zerqa Basin is evaluated using the DRASTIC method within a Geographic Information System (GIS).

A groundwater pollution potential map been prepared using an enhancement DRASTIC modeling approach.

The DRASTIC system consists of two major elements: the designation of mappable units, termed hydrogeologic settings, and the superposition of a relative rating system for pollution potential.

Hydrogeologic settings incorporate hydrogeologic factors that control round water movement and occurrence including depth to water, net recharge, aquifer media, soil media, topography, impact of the Vadoze zone media, and hydraulic conductivity of the aquifer.

These factors, which form the acronym DRASTIC, are incorporated into a modified relative ranking scheme that uses a combination of weights and ratings to produce a numerical value called the ground water pollution potential index.

Hydrogeologic settings are combined with the pollution potential indexes to create units that can be graphically displayed on a map.

Groundwater pollution potential analysis in Amman Zerqa Basin resulted in a map, which illustrates areas of varying groundwater pollution potential indexes, ranging from 47 to 159.

DRASTIC parameters are calculated from geological, soil, elevation contour maps, groundwater level data of the study area; thematic maps are prepared, and integrated through the DRASTIC model within the GIS to demarcate vulnerable zones.

The final DRASTIC (Original) values have been grouped together into low, moderate, and high pollution potential classes.

These classes represent the relative pollution potential within the study area.

The vulnerability map shows approximately more than 69.18 % of the area is classified as having low pollution potential with DRASTIC index values range between 65-96.

The No vulnerability DRASTIC index values range between 33-64 and it represent are area of 0.98%.

29.61 % is classified as having moderate pollution potential within DRASTIC index values range of 97- 128.

and 0.22 % of the total area is classified as having a High pollution potential with DRASTIC index values ranging between 129-160.

The DRASTIC Modified Lineament density values represent the relative pollution potential within the study area.

The vulnerability map shows approximately more than 87.03 % of the area is classified as having Low pollution potential with DRASTIC Modified Lineament density index values range between 76-122.The No vulnerability DRASTIC Modified Lineament density index values range between 29- 75 is classified about 5.13%.

7.83 % is classified as having Moderate pollution potential within DRASTIC index values range between 123-169.

0.01 % is classified as having a High pollution potential within DRASTIC Modified Lineament density index values range between 170-216.

The DRASTIC Modified risk assessment MD(i) values represent the relative pollution potential within the study area.

The vulnerability map shows approximately more than 70.99 % of the area is classified as having Low pollution potential with DRASTIC MD(i) values range between 69-108, The No vulnerability DRASTIC MD(i) values range between 29-68 is classified about 0.55% and 28.35 % is classified as having Moderate pollution potential within DRASTIC MD(i) values range between 109-148.and High vulnerability DRASTIC MD(i) values range between 149-188 is classified about 0.11% .

The final DRASTIC (DI+DL+MD) represent the relative pollution potential within the study area.

The vulnerability map shows approximately more than 89.66 % of the area is classified as having Low pollution potential with final DRASTIC values range between 83-131.

The No vulnerability final DRASTIC values range between 34-82 is classified about 5.95% and 4.36 % is classified as having Moderate pollution potential within final DRASTIC values range between 132-180.and High vulnerability final DRASTIC values range between 181-229 is classified about 0.03% .

Water samples from 54 wells were collected in April 2007.

There are about 41 wells occurred in the region with low risk, which has the highest concentration of nitrate in the region (60) mg / L in the well No.

(AL2573) However, the lowest concentration (5.8) mg / L were present in the well No.

(AL1392) and the average of nitrate in these wells is approximately 31 mg / L and 7 wells occurred in the region with moderate risk, which has the highest concentration of nitrate in the region (61.8) mg / L in the well No.

(AL2691) However, the lowest concentration (3.5) mg / L were present in the well No.

(AL2032) and the average of nitrate in these wells is approximately 42.1 mg / L.

4 wells occurred in the region with moderate risk, which has the highest concentration of nitrate in the region (107.2) mg / L in the well No.

(AL2690) However, the lowest concentration (81) mg / L were present in the well No.

(AL1843) and the average of nitrate in these wells is approximately 97.7 mg / L.

The multi element analyzed about 13 (AL, V, Cr, Mn, Co, Ni, Cu, Zn, As, Cd, Pb, Fe, Br) determination from the Inductivity Couple plasma (ICP) technique and then compared with standard calibration curve.

Results showed that 8 elements, there was no concentration in the samples they are (AL, V, Ni, Cu, Zn, Cd, Fe, Br),There was a concentration of the following elements (Pb, Co, Cr, Mn, AS) with varying degrees.

While the concentration of the elements (Co, Cr, Mn) within the limit by the World Health Organization and the Jordanian standard of drinking groundwater.

Main Subjects

Earth Sciences, Water and Environment

Topics

• Pollution
• Groundwater
• Jordan
• Geographical information systems
• Environmental aspects

No. of Pages

172

Table of Contents

• APA
• MLA
• AMA

Language

English

Data Type

Arab Theses

Record ID

BIM-302934