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UNIVERSITI PUTRA MALAYSIA
LEILA KHODAPANAH
FPAS 2012 16
EVALUATION OF GROUNDWATER VULNERABILITY TO CONTAMINATION AND GEOCHEMICAL CHARACTERISTICS IN AN
ALLUVIAL AQUIFER OF ESHTEHARD PLAIN, IRAN
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EVALUATION OF GROUNDWATER VULNERABILITY TO
CONTAMINATION AND GEOCHEMICAL CHARACTERISTICS IN AN
ALLUVIAL AQUIFER OF ESHTEHARD PLAIN, IRAN
LEILA KHODAPANAH
Thesis Submitted to the School of Graduate Studies, Universiti Putra Malaysia,
in Fulfilment of the Requirements for the Degree of Doctor of Philosophy
August 2012
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Abstract of the thesis presented to the Senate of Universiti Putra Malaysia
infulfilment of the requirement for the Degree of Doctor of Philosophy
EVALUATION OF GROUNDWATER VULNERABILITY TO
CONTAMINATION AND GEOCHEMICAL CHARACTERISTICS IN AN
ALLUVIAL AQUIFER OF ESHTEHARD PLAIN, IRAN
By
LEILA KHODAPANAH
August 2012
ABSTRACT
Chairman: Associate Professor Wan Nor Azmin B Sulaiman, PhD
Faculty: Environmental Studies
Amajority of the population in Eshtehard district depends upon the availability of
quality groundwater from public or private sources. Eshtehard alluvial aquifer is the
main source for irrigation, industrial and domestic uses. Recent anthropogenic
activities, though, have created a potentially vulnerable environment as groundwater
becomes exposed to contamination from municipal, industrial, and agricultural
practices threatening the short and long term sustainability of high quality
groundwater as a natural resource. Industrial discharge, waste disposal sites,
application of pesticidesand fertilizers, poultry farms and municipal sewage are
examples of potential source contamination in Eshtehard.
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Groundwater vulnerability to contamination from surface sources was evaluated for
Eshtehard aquifer using a modified GIS based DRASTIC and GOD vulnerability
methods. The study also evaluates groundwater quality and hydrochemistry.
Chemical compositions of 114 groundwater samples were used to assess the
groundwater quality in the study area and to validate the vulnerability mapsproduced
by the two mentioned methods above.
Most water samples aregrouped into two categories: relatively low mineralizedof
Ca–HCO3 type and high mineralizedwaters of Na–Cl type,which indicate the
intrusion of saline water and dissolution of carbonate minerals.Based onMANOVA
test (P=0.05) on water samples collected during wet and dry seasons didn’t show
any significant difference. Concentrations of most of the groundwater quality
indicators exceed the maximum allowable limits set by WHO drinking water
standards. The chemical analysis also indicates strong affect of anthropogenic
activities on the groundwater quality as implied by high nitrate, chloride, and
sulfateconcentrations. High levels of salinity and sodium content suggest that the
most of groundwater samples are of poor to medium quality for irrigation
purposes.The factor analysis reveals that there are two sources of solutes: (1) saline
water intrusion with high loading of Cl, Na, Ca, EC, TDS and K; (2) anthropogenic
activities, characterizedby high loadings of NO3, SO4 and Mg.
For evaluating the groundwater vulnerability in Eshtehard area based on DRASTIC
model, two challenging issues were encountered in this study: recharge estimation
and alluvial media rating. Direct groundwater recharge from precipitation in semi-
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arid areas is generally small, usually less than about 5% of the average annual
precipitation, with a high temporal and spatial variability. A combined groundwater
balance and water table fluctuation method was applied to estimate the groundwater
recharge in the research area. Original rating tables provide sufficient detail for
mapping at theregional scale, where broad ranges of geologic material are present.
However,modified rating tables improved spatial representation of input parameters
atlocal scales, which is useful for local planning.
The DRASTIC and GOD’s index values and maps for Eshtehard alluvial aquifer
were generated in GIS environment. The Classic DRASIC was modified and
optimized by incorporation of simple statistical and geostatistical techniques for the
revision of the factor rating and weighting of all the parameter. The criterionfor
these modifications was based on the correlation coefficientof each parameter with
the nitrates concentration in groundwater.The correlation coefficient was obtained as
r = 0.53, r = 0.42 and r = 0.68 (p< 0.01) for the original DRASTIC, GOD and
modified DRASTIC methods, respectively. On the basis of their statistical
significance, original ratings and weighting of the parameters werechanged in the
DRASTIC equation. Following the above-mentioned modifications,the correlation
coefficient between groundwater pollution potential and nitrates concentration was
considerably improvedand rose to 15% higher than the original method. The results
also showed that both GOD and modified DRASTIC indices values are relatively
high and thus Eshtehard aquifer is considered vulnerable to pollution. However, the
results indicated that the vulnerability prediction by DRASTIC proved superior to
GOD in this particular hydrogeologic setting. These classification of the
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vulnerability index showed that central and downstream parts of the aquifer are most
vulnerable to pollution. The salt flat in north and the alluvial fans of the southern
heights yielded moderate scores. The aquifer in and around Eshtehard township,
industrial zone and cultivation lands are highly susceptible to contamination.
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Abstrak tesis yang dikemukakan kepada Senat Universiti Putra Malaysia
sebagai memenuhi keperluan untuk ijazah Doktor Falsafah
PENILAIAN KETERDEDAHAN AIR BAWAH TANAH KEPADA
PENCEMARAN DAN CIRI-CIRI GEOKIMIA DALAM AKUIFER
ALUVIUM ESHTEHARD PLAIN, IRAN
ABSTRAK
Oleh
LEILA KHODAPANAH
August 2012
ABSTRAK
Pengerusi: Professor Madya Wan Nor Azmin B Sulaiman, PhD
Fakulti: Pengajian Alam Sekitar
Majoriti penduduk di daerah Eshtehard bergantung kepada kebersihan air bawah
tanah dari sumber-sumber awam atau swasta. Eshtehard akuifer aluvium adalah
sumber utama untuk pengairan, industri dan penggunaan domestik. Aktiviti
antropogenik yang berlaku kebelakangan ini, walau bagaimanapun, telah
mewujudkan persekitaran yang berpotensi terdedah kepada pencemaran hasil
daripada amalan perbandaran, perindustrian, pertanian dan boleh mengancam
kemapanan sebagai sumber air semula jadiyang berkualiti tinggi dalam jangka masa
pendek dan panjang. Pelepasan perindustrian, tapak pelupusan sampah, permohonan
racun perosak dan baja, ladang ternakan dan kumbahan perbandaran adalah
sebahagian dari contoh sumber pencemaran yang berpotensi di Eshtehard.
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Keterdedahan air bawah tanah kepada pencemaran dari sumber permukaan telah
dinilai bagi akuifer Eshtehard dengan menggunakan kaedah keterdedahanDRASTIC
dan GOD diubahsuai dalam persekitaran GIS. Kajian ini juga menilai kualiti air
bawah tanah dan sifat hidrokimia. Komposisi kimia mewakili 114 sampel air bawah
tanah telah dianalisisbagi tujuan menilai kualiti air bawah tanah di kawasan kajian
dan mengesahkan peta keterdedahan yang dihasilkan oleh dua kaedah tersebut.
Kebanyakan sampel air terkumpul kepada dua kategori: secara relatif agak rendah
kandungan mineral jenis Ca-HCO3 dan tinggi mineral jenis Na-Cl, yang
menunjukkan pencerobohanair masin dan pembubaran mineral karbonat telah
berlaku. Berdasarkan ujian statistik, MANOVA (P = 0.05) ke atas sampel air yang
dikumpul semasa musim hujan dan panas tidak menunjukkan sebarang perbezaan
yang signifikan. Kepekatan kebanyakan penunjuk kualiti air bawah tanah melebihi
had maksima yang ditetapkan oleh piawaian bagi air minum, WHO. Analisis kimia
juga menunjukkan kesan dari aktiviti antropogenik yang tinggi terhadap kualiti air
bawah tanah sebagimana yang ditunjukkan oleh kepekatan kandungan nitrat,
klorida, dan sulfat yang tinggi. Disamping itu, tahap kemasinan dan kandungan
natrium yang tinggi mencadangkan bahawa kebanyakan sampel air bawah tanah
terdiri dari kualiti sederhana hingga rendah tujuan pengairan. Analisis faktor
menunjukkan terdapat dua sumber bahan larut: (1) pencerobohan air masin dengan
muatan Cl, Na, Ca, EC, TDS dan K yang tinggi; (2) aktiviti antropogenik, dicirikan
oleh beban NO3, SO4 dan Mg yang tinggi.
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Untuk menilai keterdedahan air bawah tanah kepada pencemaran di kawasan
Eshtehard berdasarkan model DRASTIC, dua isu yang mencabar dihadapi dalam
kajian ini: anggaran imbuhan dan pengkadaran media aluvium. Kadar imbuhan dari
curahan hujan di kawasan separa gersang umumnya adalah kecil, biasanya kurang
5% daripada purata curahan hujantahunan, dengan ciri variasi ruang dan masa yang
agak tinggi. Gabungan kaedah imbangan air bawah tanah dan pembuaian muka air
tanah telah digunakan untuk menganggar imbuhan air bawah tanah di kawasan
kajian. Jadual pengkadaranmedia asal menyediakan butir-butir yang mencukupi
untuk pemetaan pada skala serantau, di mana julat luas bahan geologi hadir. Walau
bagaimanapun, ubahsuai kepada jadual pengkadaran jadual tersebut telah
meningkatkan perwakilan ruang parameter input pada skala tempatan, yang mana
sangat berguna untuk perancang tempatan.
Indek DRASTIC dan GOD telah dihasilkan dalam persekitaran GIS. Kaedah
DRASIC Classic telah diubahsuai dan dioptimumkan melalui penggabungan teknik
statistik mudah dan geostatistik untuk semakan semula penarafan faktor pemberatan
bagi semua parameter terlibat. Kriteria untuk pengubahsuaian ini adalah berdasarkan
pekali korelasi setiap parameter dengan kepekatan nitrat dalam air bawah tanah.
Pekali korelasi yang diperolehi sebagai r = 0.53, r = 0,42 dan r = 0.68 (p <0.01) bagi
kaedah DRASTIC asal, GOD dan kaedah DRASTIC yangdiubahsuai, secara
berturutan. Atas dasar keertian statistik ini, penilaian asal dan wajaran bagi
parameter telah diubah dalam persamaan DRASTIC. Berikutan pengubahsuaian di
atas, pekali korelasi antara potensi pencemaran air bawah tanah dan kepekatan nitrat
didapati telah jauh bertambah baik dan meningkat kepada 15% lebih tinggi daripada
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kaedah asal. Keputusan juga menunjukkan bahawa kedua-dua indek bagi kaedah
GOD dan juga DRASTIC yang diubahsuai adalah agak tinggi dan seterusnya akuifer
Eshtehard dianggap terdedah kepada pencemaran. Walau bagaimanapun, keputusan
menunjukkan bahawa ramalan keterdedahan air bawah tanah kepada pencemaran
oleh kaedah DRASTIC terbukti lebih tinggi berbanding kaedah GODbagi keadaan
hidrogeologi berkenaan.Klasifikasi indeks keterdedahan ini jelas menunjukkan
bahawa bahagian tengah dan hiliran akuifer Eshtehard paling terdedah kepada
pencemaran. Garam rata di utara dan lapisan aluvium di bahagian ketinggian selatan
telah mempengaruhi skor yang sederhana. Akuifer di bawah dan sekitar perbandaran
Eshtehard, zon perindustrian dan tanah pertanian adalah sangat mudah terdedah
kepada pencemaran.
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ACKNOWLEDGEMENTS
I would like to thank, first and foremost, Allah Almighty and God's Messenger
Muhammad (peace be upon him) for the opportunity to take on this challenge.
Thank you for providing me strength, talents, tools and special people that aided me
in the completion of this task.
I wish to express my sincere appreciation to my supervisor Assoc. Prof. Dr. Wan
Nor Azmin Bin Sulaiman for his assistance, guidance and encouragement through
this study. Thank you for the long hours that you dedicated to this script, for helping
me to achieve my best. Your support is greatly respected.
I would also like to thank to my advisory committee; Dr. Kourosh Mohammadi and
Dr. Shaharin Ibrahim for being very supportive and helpful during the work process
of this thesis. I would like to thank my classmates and friends in Faculty of
Environmental Studies for their friendship and help.
I cannot finish without saying how grateful I am with my family. I would like to
give an extra thanks to my beloved father for his love and the way he makes me feel
proud of my accomplishments, and the way he supports and encourages my work.I
also would like to thank my dear sistersLida and Nasrin and my brother Abbas, for
their love and support in every moment of my life.
I wish to express my gratitude to my dear husband, Dr. Hassan Soleimani, who has
supported me along the way to achieve my study dreams, for hislove and strong
moral support. Finally, I would like to dedicate this work to a Super Little Boy, my
lovely son, AmirAli, for being a terrific child, for having a curious, eager and
sensitive mind, for enduring my absence all the time when I was away from home
and above all bringing daily joy to my life.
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I certify that a Thesis Examination Committee has met on 16 August 2012 to
conduct the final examination of Leila Khodapanah on her thesis entitled
"Evaluation of Groundwater Vulnerability to Contamination and Geochemical
Characteristics in an Alluvial Aquifer of Eshtehard Plain, Iran" in accordance with
the Universities and University Colleges Act 1971 and the Constitution of the
Universiti Putra Malaysia [P.U.(A) 106] 15 March 1998. The Committee
recommends that the student be awarded the Doctor of Philosophy.
Members of the Thesis Examination Committee were as follows:
Ahmad Makmom bin Abdullah, PhD
Associate Professor
Faculty of Environmental Studies
Universiti Putra Malaysia
(Chairman)
Mohamad Pauzi Zakaria, PhD
Professor
Faculty of Environmental Studies
Universiti Putra Malaysia
(Internal Examiner)
Mohammad Firuz bin Ramli, PhD
Associate Professor
Faculty of Environmental Studies
Universiti Putra Malaysia
(Internal Examiner)
Kyoung-Woong Kim, PhD
Professor
School of Environmental Science and Engineering
Gwangju Institute of Science and Technology
South Korea
(External Examiner)
APPROVAL
SEOW HENG FONG, PhD
Professor and Deputy Dean
School of Graduate Studies
Universiti Putra Malaysia
Date: 23 January 2013
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This thesis was submitted to the Senate of Universiti Putra Malaysia and has been
accepted as fulfillment of the requirement for the degree of Doctor of Philosophy.
The members of the Supervisory Committee are as follows:
Wan Nor Azmin B Sulaiman, PhD
Associate Professor
Faculty of Environmental Studies
University Putra Malaysia
(Chairman)
Shaharin Ibrahim, PhD
Associate Professor
Faculty of Environmental Studies
University Putra Malaysia
(Member)
Kourosh Mohammadi, PhD
Associate Professor
Tarbiat Moddaress University
Tehran, I.R.Iran
(Member)
BUJANG BIN KIM HUAT, Ph.D.
Professor and Dean
School of Graduate Studies
Universiti Putra Malaysia
Date:
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DECLARATION
I declare that the thesis is my original work except for quotations and citations,
which have been duly acknowledged. I also declare that it has not been previously,
and is not concurrently, submitted for any other degree at Universiti Putra Malaysia
or at any other institutions.
LEILA KHODAPANAH
Date: 16 August 2012
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TABLE OF CONTENT
Page ABSTRACT iii
ABSTRAK vii
ACKNOWLEDGEMENTS xi
APPROVAL xii
DECLARATION xiv
TABLE OF CONTENT xv
LIST OF TABLES xviii
LIST OF FIGURES xx
1 INTRODUCTION 1
1.1 Introduction 1
1.2 Background 2
1.3 Problem Statement 6
1.4 Research Purpose and Objectives 8
1.5 Scope of Thesis 9
2 LITERATURE REVIEW Error! Bookmark not defined. 2.1 Introduction Error! Bookmark not defined.
2.2 Groundwater Recharge Error! Bookmark not defined.
2.3 Groundwater Quality Studies Error! Bookmark not defined.
2.4 Groundwater Vulnerability Definitions Error! Bookmark not defined.
2.5 The purpose of vulnerability assessments Error! Bookmark not defined.
2.6 Approaches to groundwater vulnerability assessment Error! Bookmark
not defined. 2.6.1 Index and overlay methods Error! Bookmark not defined.
2.6.2 Process-based simulation models Error! Bookmark not
defined. 2.6.3 Statistical methods Error! Bookmark not defined.
2.7 Vulnerability assessment using Index and overlay simulation models
Error! Bookmark not defined. 2.8 Comparison of aquifer vulnerability Assessment Techniques Error!
Bookmark not defined. 2.9 Validation of groundwater vulnerability assessment Error! Bookmark
not defined. 2.10 GIS in Groundwater Vulnerability Assessment Error! Bookmark not
defined.
3 METHODOLOGY 48
3.1 Introduction 48
3.2 Study area 52
3.2.1 Location and Accessibility 52
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3.2.2 Data Collection 54
3.2.3 Climate 57
3.2.4 Physiography 61
3.2.5 Surface Water 64
3.2.6 Geology 66
3.2.7 Geoelectrical investigation 75
3.3 Well Log Analysis 81
3.4 Hydrogeology 87
3.4.1 Hydraulic Characteristics of Aquifer 88
3.4.2 Groundwater Level Fluctuations 91
3.5 Groundwater Recharge 96
3.6 Geochemical analysis 106
3.6.1 Graphical methods 111
3.6.2 Statistical methods 112
3.7 Groundwater vulnerability assessment 115
3.7.1 DRASTIC model 116
3.7.2 GOD model 122
3.8 Geostatistical techniques 125
3.8.1 Introduction to interpolation 125
3.8.2 Theoretical basis 127
4 RESULTS AND DISCUSSION 132
4.1 Introduction 132
4.2 Groundwater quality assessment 133
4.2.1 Major ion chemistry 133
4.2.2 Water classification 142
4.2.3 Hydrochemical Facies 154
4.2.4 Statistical analysis 157
4.3 Geostatistical analyses 170
4.3.1 Depth to water 171
4.3.2 Nitrate concentration map 173
4.4 Aquifer vulnerability assessment 175
4.4.1 Depth to water 176
4.4.2 Recharge 179
4.4.3 Aquifer media 182
4.4.4 Soil media 185
4.4.5 Topography 188
4.4.6 Impact of vadose zone 190
4.4.7 Hydraulic conductivity 192
4.4.8 DRASTIC index 194
4.4.9 GOD index 196
4.5 Modified DRASTIC index 200
4.6 Comparison between DRASTIC and GOD scores 206
4.7 Validation of DRASTIC and GOD 209
5 CONCLUSION 221