Current Science International Volume : 06 | Issue : 04| Oct.- Dec. 2017 ISSN: 2077-4435 Pages: 684-700

Application of Hydrogeochemical Modeling to Study Seawater Intrusion Phenomena in the area between and El-Qusier, Coast, Mohamed A. Gomaa1, Rasha A. Hussien2, Abdel-Hameed M. El-Aassar1

1 Hydrogeochemistry Department, Desert Research Center (DRC), , Egypt. 2Egyptian Nuclear Radiological and Regularoty Authority (ENRRA),Cairo, Egypt. Received: 15 August 2017 / Accepted: 25 Sept. 2017 / Publication Date: 08 Oct. 2017

ABSTRACT

This paper is dealing with the main Hydrogeochemical processes affecting groundwater salinization in the area between Marsa Alam and El-Qusier. Twenty-three groundwater samples were collected from water-bearing formations in addition to one sample from Red Sea. Hydrochemical results reflect variation in water salinities and types among the investigated groundwater samples. Studying Hydrogeochemical evolution processes in the study area reveals that the majority of samples of (Na-Cl type) that could be affected by Seawater mixing and are mostly constrained to the coastal areas. Other samples of (Ca-Mg-Cl type) are affected by mineral weathering or possibly reverse Base Exchange reactions. Applying PHREEQC model reveals that SI of most groundwater samples of Quaternary aquifer are supersaturated with dolomite (CaMg(CO3)2), calcite and aragonite (CaCO3). It is clear that groundwater chemical characteristics are mainly controlled by natural geochemical processes as dissolution of marine deposits, reverse ion-exchange and to a lesser extent by anthropogenic activities.

Key words: Groundwater Chemistry, Water-Rock Interaction, PHREEQC model, Hydrogeochemical Processes, El-Qusier and Marsa Alam.

Introduction

Egypt faces many challenges regarding water resources due to population growth and the increasing demand of water. Egypt has become under the water poverty line. It will be expected to reach per capita for 582 and 350 m3/year by 2025 and 2050, respectively. Due to overpopulation in the Nile valley, the successive governments put future plans to develop the promising areas such as Sinai and Red Sea. These two areas are identical in geographical conditions and away from the Nile River. The Red Sea region is promising for Egypt’s economic growth. The development of this area has been expanded south until Marsa Alam. In the future, it will be expected to reach the southern border with at and triangle. The only disadvantage for the development of this area that, it is suffering the water shortage problem and unsuitability of available water resources (Abou Rayan et al., 2003). The present study is focused on the area between El-Qusier and Marsa Alam, Red sea coast. This area is considered as an especially promising importance due to mining and tourist activities. This has led to a widespread need for the development and management of regional water resources in the study area. For sustainable development in such region and from the study, it has shown clearly that the water desalination is the most appropriate way to overcome the water shortage problem in the study area. So, many water desalination plants were established during last five years, such as El-Qusier water desalination plant with capacity 7500 m3/day and many plants that were established inside the scattered hotels and tourist resorts along the Red Sea coast region of El- Qusier- Marsa Alam. These desalination plants are depending mainly on drilling wells on shore to provide the requested feed water. Several studies were conducted in this area, (El-Ghazawi and Abdel Baki, 1991) investigated the groundwater in Wadi Essel basin through the study of the effect of some structural elements on groundwater. Saluma, (1992) studied groundwater on Queh-Saqia basin in El- Qusier area were four main productive aquifers have been distinguished. Indicated that there was a distinctive relationship between the alluvial, El-Dawi and Nubian sandstone aquifers. The latter aquifer may consider the main feeding source for the overlying ones. Aggour and Sadek, (2001) studied the recharge mechanism of different aquifers in the Eastern Desert. Concluding that the most

Corresponding Author: Rasha A. Hussien, Egyptian Nuclear Radiological and Regularoty Authority (ENRRA), Cairo, Egypt. E-mail: [email protected] 684 Curr. Sci. Int., 6(4): 684-700, 2017 ISSN: 2077-4435 productive aquifers are Miocene sandstone Upper and Lower Cretaceous sandstones and the Precambrian granite. The latter is continuously renewed from the present rainfall through fractures while the others reveal that the main bulk of the stored water was originated during Pleistocene pluvial times. Reda et al. (2012) present a model budget for groundwater in the Central Eastern Desert of Egypt, showing that approximately 4.8X109 m3 of recoverable groundwater is stored in sedimentary sub-basin aquifers, or approximately 550 years of water at present utilization rates. Ashraf Embaby et al. (2016) assessed the Hydrogeochemistry of groundwater in the Precambrian rocks south eastern desert, concluded that the groundwater chemical characteristics are controlled by natural geochemical processes (i.e,dissolution, ion-exchange and evaporation) but also to a lesser extent by anthropogenic activities. The aim study of this paper is to apply Hydrogeochemical model to study Seawater intrusion (SWI) phenomena and evaluate the source of water in different aquifer types and propose management policies for groundwater use in this area of study.

Physical Setting

The study area is situated on the western coast of the Red Sea in Egypt, about 140 km south of and about 160km east of the Nile Valley. It's situated between Lats. 24°15' & 26°15' N and Longs. 34°00' & 35°15' E. It covers an area of about 300 km2, Fig 1. The only permanent settlement in the region is El-Qusier city, small fishing and phosphate-mining communities with a population of about 50.000. The climate of the region is extremely arid, the rainfall is scarce over most of the study area. The rainfall intensity decreases southward. During the period of heavy showers the maximum rainfall precipitation was about 28.5mm/day (recorded in October 1993), while the minimum rainfall precipitation was about 19.5mm/day (recorded in November 1992), the air temperature reaches 40.5◦C in August in summer and decreases to 13.4◦C in January in the winter. The relative humidity reaches about 56.8 %, Mean values of the meteorological records of are indicated in Table 1.

Geomorphologic, Geologic and Hydrogeologic Settings

The Geomorphologic setting of the eastern is closely connected with its geologic structure and this is reflected on the recharge mechanism of the different aquifers. The investigated area is distinguished into two main units as in Fig. (2).

1-Coastal Plain

The coastal plain of the Red Sea and the Gulf of exhibits numerous NW-SE headlands separated by embayments. It is mainly consisted of gravel with sand forming alluvial terraces and raised beaches. It is well developed at the downstreams portions of the huge basins and ranges in elevation from 0 to 90 m. It reveals sabkhas parallel to the shoreline in the southern portion due to high evaporation.

2- The watershed areas (High lands):

The watershed areas are represented by the uplands and distinguished into 4 units as following: - The Red Sea mountainous terrain - The high plateaux -The hilly areas - The ridges

Based on the Digital Elevation Model, Fig 3. The regional slope is toward the northeastern side, i.e. towards Red sea. The elevation varies from less than 38 m (above mean sea level) at the northeast to more than 245 m in west direction.

685 Curr. Sci. Int., 6(4): 684-700, 2017 ISSN: 2077-4435

Table 1: Mean values of meteorological records at Ras Banas station for the period 1999-2006 (Egyptian Meteorological Authority).

January Feburary March April May June July August September October November December

Rainfall (mm) Mean 0.5 0 0 6.25 0 0 0 0 0 0 1.2 0

Relative humidity 53 50 47 37.8 30 30 35 32.6 34.4 47.6 55.4 56.8 %

Temperature 0C Mean 19.3 20.13 22.37 25.86 29.89 31.77 33.2 34.33 32.7 28.81 24.64 21.01

34°0'0"E 34°5'0"E 34°10'0"E 34°15'0"E 34°20'0"E 34°25'0"E 34°30'0"E 26°25'0"N ± 11 Wadi Queh7# 26°20'0"N

24 26°15'0"N Red Sea

Wadi El-Nakhil 26°10'0"N 4 #10 3 2 1 7#12 El-Quseir City 26°5'0"N

6 Wadi Zeriab 5 26°0'0"N

Mediterranean Sea 9 7 #8 # Main Aquifers Wadi Essel 25°55'0"N Quaternary # 30 Middle Miocene # Oligocene 00 Sinai 0 4.25 8.5 17 7# Cretaceous limestone Km

Western Desert Eastern Desert

R e d

26 S e 00 a S t u

d 34°45'0"E 34°50'0"E 34°55'0"E 35°0'0"E 35°5'0"E 35°10'0"E y

a r

Legend e a Study area 25°10'0"N 0 100 200 300 Km ± 22 00

26 00 30 00 34 00 25°5'0"N 21 ! 22 ! Marsa Alam

25°0'0"N 16 ! ! 23 Red Sea 15!

24°55'0"N

24°50'0"N 18 ! 19 !

24°45'0"N

20 17! !

24°40'0"N ! Quaternary samples

0 5 10 20 Km

Fig. 1: Study area, including groundwater sampling sites

686 Curr. Sci. Int., 6(4): 684-700, 2017 ISSN: 2077-4435

31 00 33 00 35 00 37 00 27 00

26 Quseir 00

Legend:

25 Red Sea Coastal Plain. Marsa Alam 00 Red Sea Mountanian Terrain.

Morphotectonic Depressions Abraq Nubian Sandstone Block. 24 Ras Banas 00

23 00

22 00 Fig 2: Geomorphological features in the study area, (Modified after Saleh, 1992).

33°40'0"E 34°0'0"E 34°20'0"E 34°40'0"E 35°0'0"E 35°20'0"E ± 26°0'0"N El-Quseir

Red Sea 25°40'0"N

25°20'0"N

Marsa Alam

25°0'0"N

Elevation 0 - 38 24°40'0"N 39 - 73 74 - 114 115 - 158 159 - 201 24°20'0"N 202 - 254

0 12.5 25 50 75 Km Fig. 3: Digital Elevation Model (DEM) for the study area

The geologic setting of the eastern desert shows the distribution of strata on both sides of the Red Sea suggests that the fundamental complex (basement rocks) were uplifted along north-northwest line after the deposition of the lower Eocene and caused the arching of the formerly unbroken cover. Increasing denudation eroded that cover. The basement complex (igneous and metamorphic rocks) represents the oldest rock exposures underlying a sedimentary cover related to Paleozoic, Mesozoic and Cenozoic Eras (Fig.4). Tectonically, the eastern desert represents one of the four segments (parallel crustal plates of Egypt), which are separated by NNW-SSE faults (El-Shazly, 1977). It comprises three main structures folds, faults and volcanisms.

687 Curr. Sci. Int., 6(4): 684-700, 2017 ISSN: 2077-4435

31 00 35 00 Mediterranean Sea

0 80 160 km

30

SINAI 00

e

l

i

N

r

e

v R i

R e d 26 S 00 Legend e Quaternary deposites a Neogene Paleogene Mesozoic Paleozoic Precambrian Extrusion Faults

Fig 4. The geological and structural map, Eastern Desert, Egypt (GSE, 1994).

The hydrogeological setting in the eastern desert is the groundwater availability from different water bearing formations and water points that exhibit different hydrogeologic and hydrochemical characteristics. Investigations of the spatial distribution of the existing wells are important in the development of groundwater resources. A field survey of the groundwater wells indicated that they exist mainly at the downstream portion of the basins (Fig. 1). These basins are running through extensional fracture zones. The groundwater exploration of the study area is still very limited to only 23 wells, in addition to one surface water (Table 2). The aquifers in the study area could be classified according to their stratigraphic position into Quaternary alluvial, Middle Miocene, Oligocene and Cretaceous limestone. The alluvial Quaternary aquifer has shallow groundwater and occurs under free water table conditions where the depth to water of shallow wells range between 10.3 m to 15 m in El-Qusier and 0 m to 120 m in Marsa Alam. Three wells are tapping Middle Miocene aquifer in wadi Essel. The depth to water ranges from 16m to 25m. In wadi El-Nakheil, the Oligocene sandstone is detected as a water bearing formation. The depth to water ranges between 3.5 and 18m. In Wadi Queh and El-Qusier old (Cretaceous limestone aquifer) the depth to water ranges from 3.5 to 75m.

Field work

Field trip has been took place within May 2015, during which twenty four groundwater samples were collected from the area between El-Qusier and Marsa Alam, (12 from El-Qusier and 11 from Marsa Alam) and 1 surface water sample from Red Sea as shown in Fig 1. Here, location (GPS), pH value, and electrical conductivity (EC) were measured in situ, in addition to the hydrogeological data, such as depth to water table, total well depth, and water-bearing formations.

Chemical Analysis

The chemical analyses of the collected water samples included the determination of EC, Total 2+ 2+ + + 2- - 2- - Dissolved Salts (TDS), pH, concentration of major ions Ca , Mg , Na , K , CO3 , HCO3 , SO4 , Cl 3- 3+ 2+ 2+ 2+ 2+ in addition to the minor components as soluble heavy metals and PO4 , Fe , Mn , Cu , Cd , Pb , Sr2+ and Si. All the analyses were done at the Central Laboratory of Desert Research Centre according to ASTM, (2002). Measurements were carried out by EC meter model Orion (150 A+), pH meter (Jenway 3510), Flame photometer (Jenway PFP 7), Ion selectivity meter (Orion model 940 with 960 titration plus), UV/Visible spectrophotometer (Thermo-Spectronic 300) and ICAP (thermo 6500). The obtained chemical data are expressed in milligram per liter (mg/l) or part per million (ppm) with values have an ionic balance within 5%. The data obtained from the chemical analyses of major and

688 Curr. Sci. Int., 6(4): 684-700, 2017 ISSN: 2077-4435

trace elements were used as input data for geochemical modeling using the PHREEQC code (Parkhurst and Appelo 1999). The PHREEQC code was used to calculate saturation indices (SI) for minerals of interest. Saturation index determines whether a solution has thermodynamic potential for further dissolution or precipitation of a mineral. The saturation indices (SI) of relevant mineral are determined using the equation: SI= log (IAP/K), where IAP is the ion activity products, and KT is the solubility product of a mineral for a given temperature.

Table 2: Hydrogeological data of the wells tapping the studied aquifers. Well No. Location Aquifer Formation Type Depth To Water (m) TDS (mg/l) 1 El-Qusier, Shore Quaternary Alluvial Drilled 12 33216 2 El-Qusier, Shore Quaternary Alluvial Drilled 12 29952 3 El-Qusier, Shore Quaternary Alluvial Drilled 15 33600 4 El-Qusier, Shore Quaternary Alluvial Drilled 15 33536 5 Wadi Zeriab Quaternary Alluvial Hand dug 12.53 13670.4 6 Wadi Zeriab Quaternary Alluvial Hand dug 10.3 2950.4 7 Wadi Essel Middle Miocene Drilled 16 2726.4 8 Wadi Essel Middle Miocene Drilled 16 2694.4 9 Wadi Essel Middle Miocene Drilled 25 2393.6 10 Wadi El-Nakheil Oligocene sandstone Drilled 3.5 3232 11 Wadi Queh Cretaceous limestone Hand dug 75 2080 12 El-Qusier, old Cretaceous limestone Hand dug 3.5 8403.2 13 Mersa Alam Quaternary Alluvial Drilled 120-150 36992 14 Mersa Alam Quaternary Alluvial Drilled 120-150 33360 15 Mersa Alam Quaternary Alluvial Drilled 120-150 32380 16 Mersa Alam Quaternary Alluvial Hand dug 5.75 7570 17 Mersa Alam Quaternary Alluvial Flowing 0 33560 18 Mersa Alam Quaternary Alluvial Hand dug 3.7 6279 19 Mersa Alam Quaternary Alluvial Drilled 100 43347 20 Mersa Alam Quaternary Alluvial Drilled 33 46341 21 Mersa Alam Quaternary Alluvial Flowing 0 25038 22 Mersa Alam Quaternary Alluvial Flowing 0 39770 23 Mersa Alam Quaternary Alluvial Hand dug 2 6800 24 El-Hamrawain Red sea Surface water 0 34432

Results and Discussion

General Hydrochemistry

The results of chemical analysis listed in Table 3. Indicate a wide range of groundwater chemistry in different aquifers of the study area as in the followings: - PH values range between 7-8.4 with an average value of 7.69 in El-Qusier area (neutral to slightly alkaline) and between 8.1-9 with an average value of 8.39 in the Marsa Alam area (alkaline). In general, PH of water samples compared with WHO (2011) standards, all samples fall within the recommended limit (6.5 to 8.5) for human consumption except sample (no. 22) that have high PH value of 9. - EC values vary between 3250-52,500 µs/cm with an average value of 22,783 µs/cm in El-Qusier area which more less than the Marsa Alam area that range between 9200-57800 µs/cm with an average value of 39577 µs/cm. All of groundwater samples are above the permissible limits of WHO (2011) of 1,500 µs/cm.

689 Curr. Sci. Int., 6(4): 684-700, 2017 ISSN: 2077-4435

- Cations spatial distribution in El-Qusier Fig. 5 and Marsa Alam Fig. 6 illustrates that the maximum concentration of Na+ is found in the alluvial Quaternary aquifer (13,000 mg/l in well, no. 1) located in the coastal areas of both El-Qusier and Marsa-Alam areas. Potassium K+ concentrations show nearly the same trend as sodium, where it ranges from 7- 600 mg/l and 31-500 mg/l in El-Qusier and Marsa- Alam respectively. Calcium concentrations show a large range of variation from 240 in well no. 9 to 1236 mg/l in well no. 13, 17. Magnesium concentrations range between 138 mg/l in well no. 8 to 2740 mg/l in well no. 20.

Table 3: Chemical data of the investigated groundwater samples.

Well Cations (mg/l) Anions (mg/l) No. Temp. EC (µs/cm) 0 pH ( C) Na K Mg Ca Cl SO4 CO3 HCO3

1 51900 39.6 7.3 13000 600 951.2 378.1 23167 2055.8 9 61 2 46800 39.1 7.6 10800 550 864.7 585.2 19716 1923.4 6 67.1 3 52500 37.9 7.5 11200 580 1187 668.9 21688 2083.2 9 54.9 4 52400 37.7 7.6 12200 600 1294 663.2 23167 1677.6 6 67.1 5 21360 35.2 7.4 3500 170 538.6 824.6 7270 1945.4 3 54.9 6 4610 28.7 8.1 640 25 97.02 289.9 1121 921.04 3 48.8 7 4260 37.7 8.1 520 10 136.5 273.6 1072 760 18 112.9 8 4210 36.5 8 500 9 138 246.4 1060 710 12 97.6 9 3740 36.5 7.8 500 11 108.5 240.1 1060 620 0 39.65 10 5050 38.1 7 660 27 74.46 247.2 1651 158.18 0 9.15 11 3250 30.2 8.4 400 7 70.82 311 813 700.7 12 79.3 12 13130 36.5 7.5 1900 63 280 893 3598 2700 6 64.05 13 57800 38.9 8.4 9000 420 1900 1236 19000 2700 7 126 14 57300 38.9 8.4 8900 400 1800 1200 18900 2100 7 120 15 55300 38.9 8.4 8700 420 1700 1000 18000 2500 10 113 16 12300 28.7 8.4 1100 31 1001 247 4059 1079 0 113 17 43500 28 8.4 8500 450 1752 1236 19800 1781 0 100 18 9600 37.8 8.2 900 34 400 824 3465 506 0 299 19 51600 38.5 8.3 11125 410 2242 1230 24284 4000 0 113 20 56000 37.9 8.1 11500 410 2740 1230 26664 3720 0 153 21 42000 28 8.2 7100 260 1100 812 13400 2300 0 133 22 52900 28.5 9 10750 500 1850 609 17021 8966 33 93 23 9200 37.9 8.2 850 32 400 1000 2772 1681 0 150 24 53800 38.4 7.3 13000 600 951.2 378 23166.7 2055.8 9 61

Anions spatial distribution in El-Qusier Fig. 5 and Marsa Alam Fig. 6 shows the same trend as anions distributions where, they increase in the coastal areas as in El-Qusier and decrease towards SE direction in Marsa-Alam area. The maximum Cl- concentrations is found in well, no. 20 (Cl- = 26,664 mg/l) that could be affected by seawater encrochroment at Marsa-Alam area. On the contrary, bicarbonate concentration shows low variation range between 9.15 mg/l in well no.10 to 300 mg/l in well no. 18.

690 Curr. Sci. Int., 6(4): 684-700, 2017 ISSN: 2077-4435

34°0'0"E 34°5'0"E 34°10'0"E 34°15'0"E 34°20'0"E 34°25'0"E 34°30'0"E 34°0'0"E 34°5'0"E 34°10'0"E 34°15'0"E 34°20'0"E 34°25'0"E 34°30'0"E 26°25'0"N 26°25'0"N ± ± 11 Wadi Queh Wadi Queh7#11 #7 26°20'0"N 26°20'0"N

24 24 26°15'0"N Red Sea 26°15'0"N Red Sea

Wadi El-Nakhil Wadi El-Nakhil 26°10'0"N 26°10'0"N 4 # 4 #10 3 10 3 2 2 1 1 12 7#12 El-Quseir #7 El-Quseir City City 26°5'0"N 26°5'0"N

6 6 Wadi Zeriab 5 Wadi Zeriab 5 26°0'0"N 26°0'0"N

9 7 Na(mg/L) #9 #7 Cl (mg/L) # Wadi Essel#8 Wadi Essel#8 400 - 2,181 814 - 4,173 25°55'0"N 25°55'0"N 2,182 - 4,443 4,174 - 8,395 4,444 - 6,849 8,396 - 12,788 6,850 - 9,160 12,789 - 17,096 0 4.75 9.5 19 0 4.75 9.5 19 17,097 - 22,782 9,161 - 12,673 Km Km

34°0'0"E 34°5'0"E 34°10'0"E 34°15'0"E 34°20'0"E 34°25'0"E 34°30'0"E 34°0'0"E 34°5'0"E 34°10'0"E 34°15'0"E 34°20'0"E 34°25'0"E 34°30'0"E 26°25'0"N ± 26°25'0"N ± Wadi Queh11 7# Wadi Queh#711 26°20'0"N 26°20'0"N

24 24 26°15'0"N Red Sea 26°15'0"N Red Sea

Wadi El-Nakhil Wadi El-Nakhil 26°10'0"N 26°10'0"N 4 4 #10 3 #10 3 2 2 1 1 7#12 El-Quseir #712 El-Quseir City City 26°5'0"N 26°5'0"N

6 6 Wadi Zeriab 5 Wadi Zeriab 5 26°0'0"N 26°0'0"N

Mg (mg/L) 9 7 SO4 (mg/L) 9 7 #8 # #8 # 71 - 268 Wadi Essel 158 - 587 Wadi Essel 25°55'0"N 25°55'0"N 269 - 479 588 - 1,145 480 - 685 1,146 - 1,693 686 - 900 1,694 - 2,082 0 4.75 9.5 19 0 4.75 9.5 19 901 - 1,261 Km 2,083 - 2,690 Km

34°0'0"E 34°5'0"E 34°10'0"E 34°15'0"E 34°20'0"E 34°25'0"E 34°30'0"E 34°0'0"E 34°5'0"E 34°10'0"E 34°15'0"E 34°20'0"E 34°25'0"E 34°30'0"E 26°25'0"N 26°25'0"N ± ± 11 Wadi Queh Wadi Queh7#11 #7 26°20'0"N 26°20'0"N

24 24 26°15'0"N Red Sea 26°15'0"N Red Sea

Wadi El-Nakhil Wadi El-Nakhil 26°10'0"N 26°10'0"N 4 4 #10 3 #10 3 2 2 1 1 12 7#12 El-Quseir 7# El-Quseir City City 26°5'0"N 26°5'0"N

6 6 Wadi Zeriab 5 Wadi Zeriab 5 26°0'0"N 26°0'0"N

Ca(mg/L) 9 7 HCO3 (mg/L) 9 7 #8 # #8 # 241 - 390 Wadi Essel 9 - 23 Wadi Essel 25°55'0"N 25°55'0"N 391 - 505 24 - 41 506 - 579 42 - 66 580 - 681 67 - 84 0 4.75 9.5 19 0 4.75 9.5 19 682 - 893 Km 85 - 113 Km

Fig. 5: Spatial distribution of cations (Na, Mg, Ca; left column) and anions (Cl, SO4, HCO3, right column) in El-Qusier area.

691 Curr. Sci. Int., 6(4): 684-700, 2017 ISSN: 2077-4435

34°45'0"E 34°50'0"E 34°55'0"E 35°0'0"E 35°5'0"E 35°10'0"E 34°45'0"E 34°50'0"E 34°55'0"E 35°0'0"E 35°5'0"E 35°10'0"E 25°10'0"N ± 25°10'0"N ±

25°5'0"N 21 25°5'0"N 21 ! 22 ! 22 ! ! Red Sea Red Sea 25°0'0"N 25°0'0"N

16! 16 ! 23 ! ! 23 15! 15!

24°55'0"N 24°55'0"N

24°50'0"N 18 24°50'0"N 18 ! ! 19 19 ! !

24°45'0"N 24°45'0"N

Na (mg/L) 20 20 ! Cl (mg/L) ! 17 17 867 - 3,952 ! ! 2,807 - 9,261 3,953 - 5,787 24°40'0"N 24°40'0"N 9,262 - 12,816 5,788 - 7,204 12,817 - 16,090 7,205 - 8,705 16,091 - 19,738 8,706 - 11,498 0 5 10 20 0 5 10 20 19,739 - 26,660 Km Km

34°45'0"E 34°50'0"E 34°55'0"E 35°0'0"E 35°5'0"E 35°10'0"E 34°45'0"E 34°50'0"E 34°55'0"E 35°0'0"E 35°5'0"E 35°10'0"E

25°10'0"N ± 25°10'0"N ±

25°5'0"N 21 25°5'0"N 21 ! 22 ! 22 ! ! Red Sea Red Sea 25°0'0"N 25°0'0"N

16 16! ! ! 23 ! 23 15! 15!

24°55'0"N 24°55'0"N

24°50'0"N 18 24°50'0"N 18 ! ! 19 19 ! !

24°45'0"N 24°45'0"N

20 20 Mg (mg/L) ! SO4 (mg/L) ! 17 17 ! ! 400 - 996 506 - 2,330 24°40'0"N 997 - 1,345 24°40'0"N 2,331 - 3,158 1,346 - 1,675 3,159 - 4,352 1,676 - 2,015 4,353 - 6,076 6,077 - 8,960 0 5 10 20 2,016 - 2,730 0 5 10 20 Km Km

34°45'0"E 34°50'0"E 34°55'0"E 35°0'0"E 35°5'0"E 35°10'0"E 34°45'0"E 34°50'0"E 34°55'0"E 35°0'0"E 35°5'0"E 35°10'0"E 25°10'0"N ± 25°10'0"N ±

25°5'0"N 21 25°5'0"N 21 ! 22 ! 22 ! ! Red Sea Red Sea 25°0'0"N 25°0'0"N

16! 16! ! 23 ! 23 15! 15!

24°55'0"N 24°55'0"N

24°50'0"N 18 24°50'0"N 18 ! ! 19 19 ! !

24°45'0"N 24°45'0"N

20 20 Ca (mg/L) ! HCO3 (mg/L) ! 17 17 ! ! 249 - 779 93 - 132 24°40'0"N 780 - 895 24°40'0"N 133 - 158 896 - 992 159 - 192 993 - 1,104 193 - 237 1,105 - 1,236 0 5 10 20 238 - 299 0 5 10 20 Km Km

Fig. 6: Spatial distribution of cations (Na, Mg, Ca; left column) and anions (Cl, SO4, HCO3, right column) in Marsa-Alam area.

692 Curr. Sci. Int., 6(4): 684-700, 2017 ISSN: 2077-4435

2- The concentration of SO4 ranges between 620 mg/l in well no. 9 and 4000 mg/l in well, no.19 such high values may be due to leaching and dissolution of sulfate salts. - The cation chemistry is in the following order: Na> Mg> Ca>K (Quaternary aquifer) and Na> Ca> Mg>K in (Middle Miocene, Oligocene and Cretaceous aquifers) and Cl> SO4>HCO3 for anions. Where Cl and Na are the dominant ones showing a complete resemblance to that of the salt water in Quaternary aquifer may be due to the impact of marine conditions and the final stage of groundwater evolution (Sulin, (1948). But in Middle Miocene, Oligocene and Cretaceous limestone aquifers an ion-exchange process between Na and Ca may be occurring. - 2- -Hypothetically, the ions of the strong acids (Cl and SO4 ) form a chemical combination with alkalis (Na+ and K+) and the rest of the acid radicals combine with the alkaline earths (Ca2+and Mg2+) (Collins 1923; Zaporozec 1972). In the present study, the combination between major cations and anions reveals the formation of two main assemblages of the hypothetical salts combinations in the study area. These recorded assemblages are: I- NaCl, KCl, MgCl2, MgSO4, CaSO4 and Ca (HCO3)2, Samples no. (1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 12, 15, 16, 20, 21& 22). II- NaCl, KCl, MgCl2, CaCl2, CaSO4 and Ca (HCO3)2, Samples no. (14, 17, 18, 19, 24).

The majority of groundwater samples is characterized by assemblages I&II (more advanced stage of chemical development). The presence of MgCl2 and CaCl2 salts in the Quaternary alluvial groundwater is due to the dissolution of minerals and effect of seawater intrusion at these wells. The major ion chemistry is shown by Piper diagram in Fig 7. Piper diagram (Piper, (1953) is drawn by plotting the proportions (in equivalents) of the major cations (Ca, Mg, Na, K) on one triangular diagram, the proportions of the major anions (CO3+HCO3, Cl, SO4) on another, and combining the information from the two triangles on a quadrilateral. The position of this plotting indicates the relative composition of groundwater in terms of the cation-anion pairs that correspond to four vertices of the field. All groundwater samples fall where the subdivision of alkaline metals exceeds alkaline earths and strong anions exceed weak acid anion, reflecting a sodium-chloride water type.

Fig. 7: Piper diagram for different aquifers in the study area

693 Curr. Sci. Int., 6(4): 684-700, 2017 ISSN: 2077-4435

A hydrochemical diagram proposed by Chadha, (1999) has been applied in this study to interpret the hydrochemical processes occurring in the study area. The same procedure was successfully applied by Karmegam et al. (2010); Vandenbohede et al. (2010) in a coastal aquifer to determine the evolution of two Hydrogeochemical processes. The data were converted to percentage reaction values (milliequivalent percentage) and expressed as the difference between alkaline earths (Ca+Mg) and alkali metals (Na+K) for cations, and the difference between weak acidic anions (HCO3+CO3) and strong acidic anions (Cl+SO4). The hydrochemical processes suggested by Chadha 1999 are indicated in each of the four quadrants of the gra pH. These are broadly summarized as: Field 1: Ca-HCO3 type of recharging water Field 2: Ca-Mg-Cl type of reverse ion exchange water Field 3: Na-Cl type of end-member waters (Seawater) Field 4: Na-HCO3 type of base ion-exchange waters The resultant diagram is shown in Fig 8. and the majority of samples falls in the Field 3 (Na- Cl) suggesting that the waters show typical Seawater mixing and are mostly constrained to the coastal areas. Some samples (Nos. 16, 18& 23 of Quaternary and No.7, 8 of Middle Miocene and No.11 of Cretaceous Limestone aquifers) are located in the Field 2 (Ca-Mg-Cl type) reverse ion- exchange revealing that these groundwater samples have (Ca+Mg) in excess to (Na+K) may be from mineral weathering or possibly reverse base exchange reactions of Ca+Mg into solution and subsequent absorption of Na into mineral surfaces (Karmegan et al., 2010) such as in equation (1): Ca2+ - clay + 2Na+ (water) Ca2+ (water) + 2Na+ - clay (1)

Fig. 8: Chadha,s geochemical process evolution plot.

Estimate Mixing with different water

Major element data were used to confirm the source of the groundwater using the concentration rate (CR) and Enrichment factor (EF) relative to Chloride of Seawater. The concentration ratio (CR) of Cl- in the studied groundwater in relation to its concentration in Seawater Table 4. Indicates the mixing rate of Seawater and Meteoric water. The results indicate that in Quaternary aquifer about (66.7% of groundwater samples in El-Qusier and 27% in Marsa Alam have CR>0.82 reflecting high mixing ratio with Seawater. On the other hand, this mixing effect was less pronounced in Middle Miocene, Oligocene and Cretaceous Limestone aquifers that may be recharged by seasonal precipitation. The chloride is chosen as an indicator of sea intrusion, since seawater solutes are specifically characterized by excess Cl-. Also, the Enrichment factor (EF) is calculated to show the degree of enrichment of a given common element (i.e., Na+, Mg2+) compared with the relative abundance of this element in Seawater. The Enrichment Factor is defined as (Duce et al., - - 1975): EF (X) = (X/Cl ) rain / (X/Cl ) sea

694 Curr. Sci. Int., 6(4): 684-700, 2017 ISSN: 2077-4435

- - Where: (X/Cl ) rain is the ratio between substance X concentration and Cl concentration in rainwater, - - and (X/Cl ) sea is the ratio of substance X relative to Cl in seawater. Calculation of EF is given in Table 4. revealed that EF for Mg2+ was more than 1 in all groundwater samples and near 1 (with 3 samples below 0.5) for Na+. These results clarify the impact of rock-water interactions where the water bearing formation is composed mainly of limestone and dolomite. Fig 9. shows the rate of influence of mixing rate of seawater whereas carbonate or terrestrial materials have effective contributions in groundwater chemistry. Ionic ratios are commonly used to evaluate the salinization sources and the origin of groundwater in coastal aquifers (Barbecot et al., 2000). The changes in the chemical composition of fresh groundwater are caused by mixing with different waters as well as by chemical reactions. The Na/Cl ratio is used for discriminating brackish and saline water, where the values of this ratio are always higher than unity in the worldwide fresh and meteoric water while it is less than unity in seawater or saline water (Starinsky et al., 1983). Fig 10. Shows that most of groundwater has a low Na/Cl ratio compared to seawater, and groundwater with the highest Cl- concentrations is characterized by a low Ca/Cl and Mg/Cl ratios. There is no discernable difference between the aquifers in the study area. These ratios of brackish groundwater are relatively low compared to fresh groundwater reflecting the dominance of Cl- as the main anion. The water-rock interaction, the effect of solution and leaching processes on the mineralization of groundwater in the studied aquifer was studied with the implementation of the PHREEQC model (follow the convention: saturation index= log [IAP/KT]). Although the source of recharge of this area was rainfall, it is clear that the increase of groundwater salinity is due to soluble salts in marine deposits and mixing with seawater. The data obtained from the PHREEQC model was summarized in Table 4. These data revealed that most groundwater samples of Quaternary aquifer are supersaturated with dolomite (Ca-Mg (CO3)2), calcite and aragonite (CaCO3). One of the most important hydrochemical coefficients (ion ratios) is the Ca/Mg ratio. Most of the analyzed groundwater samples from different aquifers have an Ca2+/Mg2+ ratio less than unity, i.e., magnesium ions exceed calcium ions except Wadi Zeriab (no.6), Wadi Essel (no. 7,8,9), sample no. 10 of Wadi Nakheil and samples no. 11,12 of Wadi Queh where calcium exceeds magnesium ions. The values of Ca2+/Mg2+ ratios were calculated (meq/l concentration), they range from 0.15 to 2.63 with an average value of 0.86. These values are above that of the seawater (0.24) but below that of the rainwater in the study area (1.12).This is due to the presence of CaCO3 and (CaMg(CO3)2) materials which is confirmed by the saturation indices of carbonate minerals in the groundwater samples. It seems reasonable that the sources of the magnesium leading to the increase of Mg2+ in the groundwater are the dolomitic limestone and dolomite which form the main rocks in the watershed area and water-bearing formation where these rocks are subjected to leaching and dissolution after rainfall which recharges groundwater.

Statistical study

Factor analysis is a useful statistical tool for the geochemical data interpretation, evaluating the fundamental factors governing the general behavior of the aquifer system. The most important feature of factor techniques is their ability to reduce a large number of variables down to a smaller number of factors. Three main reasons can be identified for the application of factor analysis on an original data set: (i) to detect and identify groups of well correlated original variables, (ii) to reduce the number of variables under investigation, and (iii) to produce new combinations of the original variables (groups) that can then be used as new variables in some further analyses (Davis, 1986; Papathe-odorou et al., 2007). The statistical multivariate treatment based on Principal Component Analysis (PCA) has been applied to the study area. Correlation matrix (Table 5) illustrate that the relationships between TDS to Na+, Cl- to Mg2+ and Mg2+ to Cl+, Ca2+ show relatively high correlation levels (0.96, 0.97, 0.93, 0.87 and 0.73) respectively. Ca2+, Mg2+ are thus significant and attributable to seawater intrusion significantly raising the concentration of these ions in the water, as well as, the chloride concentration in the water is raised proportionally. According to the principle component analysis (PCA), Table 6, the set of parameters was grouped in four major factors explaining various processes affecting groundwater chemistry.

695 Curr. Sci. Int., 6(4): 684-700, 2017 ISSN: 2077-4435

Factor 1 was able to explain 52% of the variance of the total geochemical data set and has a + + 2+ - 2- strong positive loading (>0.5) for EC, TDS, Na , K , Mg , Cl and SO4 , suggesting seawater intrusion. Factor 2 was able to explain 16% of the variance of the total geochemical data set and has - strong positive factor loadings for pH and 0.685 for HCO3 . High pH values 7-8.4 in El-Qusier and 8.1-9 in Marsa-Alam areas enhance the conversion of dissolved carbon dioxide to bicarbonate ion as in El-Qusier area. Increasing the pH beyond 8.3, the bicarbonate ion is converted to carbonate ion as in Marsa-Alam area that carbonate concentration reached to 33 mg/l in well no.22.

Heavy Elements Distribution

Heavy element concentrations were determined and compared to national drinking water guidelines (WHO, 2011) to assess whether the waters contain high concentrations of elements that could affect human health in the hypothetical case that impact shallow groundwater used for drinking water purposes. The results of the collected water samples include: Fe, Mn, Cd, Cu, Pb, Sr, P, Si and SiO2 were shown in Table 7. The concentration of iron varies from 0.0052-26.51 mg/L (average of 4.179 mg/L). These high values compared with 0.3 mg//L for WHO, 2011) may be due to weathering of source rocks rich in these minerals. Concentration of Mn varies from (0.0246-2.041 mg/L) with an average value of 0.468 mg/L compared with the permissible limits of 0.05 mg/L for WHO 2011.

Table 4: Concentration rate (CR), Enrichment Factor (EF) for Na, Mg with Saturation indices (SI) in the study area

Well no. CR EF (Na) EF (Mg) Anhydrite Aragonite Calcite Dolomite Gypsum Sulfur 1 1.00 1.00 1.00 -0.95 -0.37 -0.24 0.44 -0.83 -51.25 2 0.85 0.98 1.07 -0.76 0.12 0.25 1.18 -0.63 -53.61 3 0.94 0.92 1.33 -0.72 -0.01 0.12 1.01 -0.59 -52.65 4 1.00 0.94 1.37 -0.84 0.13 0.26 1.33 -0.7 -53.54 5 0.31 0.86 1.81 -0.43 0.01 0.15 0.57 -0.26 -51.34 6 0.05 1.02 2.12 -0.76 0.35 0.49 0.88 -0.55 -56.08 7 0.05 0.84 2.44 -0.82 0.84 0.98 2.1 -0.67 -57.63 8 0.05 0.84 2.33 -0.89 0.63 0.76 1.71 -0.73 -56.43 9 0.05 0.86 2.30 -0.92 -0.57 -0.43 -0.78 -0.76 -54.87 10 0.07 0.48 6.01 -1.46 -1.7 -1.57 -3.19 -1.31 -49.29 11 0.04 0.80 1.92 -0.78 0.95 1.09 1.93 -0.58 -58.78 12 0.16 0.77 2.16 -0.14 0.26 0.39 0.72 0.02 -52.06 13 0.82 0.46 2.81 -0.41 1.22 1.35 3.4 -0.28 -59.94 14 0.82 0.82 2.25 -0.52 1.2 1.33 3.36 -0.39 -60.04 15 0.78 0.77 2.50 -0.51 1.13 1.26 3.26 -0.37 -59.94 16 0.18 0.94 2.00 -1.15 0.67 0.81 2.63 -0.95 -58.73 17 0.85 0.55 3.51 -0.59 1.05 1.19 2.97 -0.4 -58.65 18 0.15 0.86 3.11 -0.83 1.58 1.72 3.61 -0.68 -58.6 19 1.05 0.84 3.18 -0.29 1.06 1.19 3.15 -0.16 -58.94 20 1.15 0.84 2.50 -0.36 1.04 1.17 3.21 -0.23 -57.34 21 0.58 0.71 1.10 -0.55 0.92 1.06 2.67 -0.36 -56.83 22 0.73 0.88 2.13 -1.57 -2.84 -260.7 -2.58 -1.37 -63.29 23 0.12 0.94 1.90 -0.26 1.32 1.46 2.97 -0.11 -58.08 24 1.00 1.00 1.00 -0.96 -0.45 -0.31 0.29 -0.83 -51.1

696 Curr. Sci. Int., 6(4): 684-700, 2017 ISSN: 2077-4435

Fig. 9: The concentration ratio of Cl- Vs Enrichment factor of Na, Mg

Fig. 10: Graphs showing (a) Na/Cl ratios; (b) Mg/Ca; (c) Ca/Cl ratios; (d) Mg/Cl ratios vs. Cl concentrations (epm) in groundwater. SW indicates seawater based on sample composition reported in Table 2.

697 Curr. Sci. Int., 6(4): 684-700, 2017 ISSN: 2077-4435

Table. 5: Correlation matrix between variables of the study area.

EC TDS Temp DTW pH Na K Ca Mg CO3 HCO3 Cl SO4

EC 1.00

TDS 0.98 1.00

Temp 0.21 0.17 1.00

DTW 0.42 0.37 0.35 1.00

pH 0.16 0.21 0.41 0.34 1.00

Na 0.97 0.96 0.23 0.27 0.01 1.00

K 0.94 0.92 0.22 0.23 0.04 0.98 1.00

Ca 0.63 0.66 0.21 0.45 0.35 0.51 0.45 1.00

Mg 0.88 0.93 0.08 0.45 0.44 0.81 0.73 0.73 1.00

CO3 0.16 0.14 -0.11 0.04 0.25 0.17 0.21 0.23 0.04 1.00

HCO3 0.05 0.08 0.07 0.10 0.56 -0.04 - 0.09 0.42 0.23 -0.13 1.00

Cl 0.97 0.98 0.25 0.33 0.06 0.98 0.95 0.60 0.87 0.05 0.03 1.00

SO4 0.58 0.65 -0.17 0.09 0.41 0.56 0.51 0.37 0.63 0.57 0.038 0.51 1.00

Table 6: Varimax factor loading matrix, communalities for variable analyzed the variance and cumulative proportion of variance of each factor Factor 1 Factor 2 Factor 3 Factor 4 Communalities

EC (µS/cm) 0.980 -0.116 -0.011 -0.016 0.973 TDS (mg/l) 0.992 -0.061 -0.031 -0.079 0.995 Temp 0.205 -0.456 0.550 0.507 0.810 DTW (m) 0.446 0.191 0.388 0.635 0.789 pH 0.267 0.921 -0.089 0.073 0.932 Na (mg/l) 0.944 -0.269 -0.096 -0.078 0.979 K (mg/l) 0.905 -0.330 -0.135 -0.067 0.949 Ca (mg/l) 0.703 0.297 0.462 -0.120 0.810 Mg (mg/l) 0.936 0.203 0.073 -0.097 0.931

CO3 (mg/l) 0.174 0.138 -0.762 0.534 0.915

HCO3 (mg/l) 0.132 0.685 0.433 -0.092 0.682 Cl (mg/l) 0.961 -0.211 0.038 -0.119 0.983

SO4 (mg/l) 0.662 0.272 -0.548 0.045 0.815 Variance % 51.881 15.591 13.676 7.812

Cumulative % 51.881 67.473 81.149 88.961

698 Curr. Sci. Int., 6(4): 684-700, 2017 ISSN: 2077-4435

Table 7: Trace elements concentrations for collectin groundwater samples

Well Fe Mn Cd Cu pb Sr Si SiO2 No. mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l 1 <0.02 <0.003 <0.001 <0.003 <0.006 5.45 0.86 1.84 2 <0.02 <0.003 <0.001 <0.003 <0.006 6.79 1.80 3.85 3 0.2128 <0.003 <0.001 <0.003 <0.006 9.14 2.22 4.76 4 0.165 <0.003 <0.001 <0.003 <0.004 9.63 2.52 5.39 5 1.124 0.0609 <0.001 <0.003 0.0126 27.51 9.06 19.38 6 <0.02 <0.003 <0.001 <0.003 0.0114 12.45 12.45 26.63 7 1.506 0.3742 <0.001 <0.003 <0.004 3.95 12.33 26.38 8 19.59 0.4835 <0.001 <0.003 0.1154 3.80 13.43 28.73 9 26.51 1.057 <0.001 <0.003 <0.004 3.26 2.20 4.71 10 11.06 1.261 <0.001 <0.003 <0.004 7.86 1.49 3.19 11 <0.02 <0.003 <0.001 <0.003 <0.006

12 2.41 1.001 <0.001 <0.003 <0.006 23.34 5.05 10.81 13 0.2283 0.0462 <0.001 0.0349 <0.004 9.20 5.81 12.42 14 0.501 0.0658 <0.001 0.0244 <0.004 9.87 5.90 12.63 15 0.0052 0.0394 <0.001 0.0335 <0.004 6.78 5.58 11.93 16 0.459 0.0246 <0.001 0.0262 0.0064 12.26 12.31 26.33 17 0.1087 0.2817 <0.001 0.04 <0.004 14.01 6.80 14.55 18 2.146 2.041 <0.001 0.042 <0.004 12.96 13.11 28.05 19 <0.02 <0.001 <0.001 0.037 <0.004 7.03 2.68 5.73 20 <0.02 <0.001 <0.001 0.029 <0.004 12.54 7.48 15.99 21 <0.02 0.044 <0.001 0.0232 <0.004 8.24 <0.02

22 0.3172 0.1636 <0.001 0.037 <0.004 15.59 10.14 21.69 23 0.53 0.0799 <0.001 0.0591 0.0141 37.27 17.44 37.31 24 <0.02 <0.003 <0.001 <0.003 <0.006 6.11

Min 0.0052 0.0246 0.0232 0.0064 3.26 0.86 1.84

Max 26.51 2.041 0.0591 0.1154 37.27 17.44 37.31

Average 4.17 0.46 0.035 0.031 11.52 7.17 15.35

WHO 2011 0.3 0.05 0.005 1 0.05

Conclusion

The main aquifers in the area between Marsa-Alam and El-Quseir are Quaternary Alluvial, Middle Miocene, Oligocene, Cretaceous limestone. The groundwater salinity is classed between highly saline and very highly saline groundwater at El-Qusier shore and Marsa-Alam coastal areas. This may be due to evaporation, limited recharge and leaching of some soluble salts in rocks (limestone, dolomite, gypsum, shale and marl). However, Na and Cl presence in majority of groundwater samples reflect the contribution of leaching and dissolution of marine deposits. Interaction of seawater-aquifer groundwater can generate an increase in salinity due to lateral seawater intrusion and upcoming of deep saline water due to high pumping. Pumping groundwater in these areas, especially shallow aquifers should be managed to protect these aquifers from further deterioration with some recommendations in the future to desalinate brackish and saline water to improve its quality.

699 Curr. Sci. Int., 6(4): 684-700, 2017 ISSN: 2077-4435

References

Abou Rayan, M.B. Djebedjian, I. Khaled, S. El-Sarraf, 2003. Desalination option within water demand management and supply for red sea coast in Egypt", Seventh International Water Technology Conference, IWTC, Cairo, Egypt. Ahmed W. Mohamed, 2005 .Geochemisry and sedimentology of core sediments and the influence of human activities; Qusier, and Hurghada harbors, Resacoat, Egypt', Egyptian Journal of aquatic research, vol. 31, 1. Ahmed, K. A., 2010. Evaluation of water resources of some drainage basins in the area between El Quseir and El Shalateen, Red Sea Coast, Eastern Desert, Egypt." Unpubl. PH.D. Thesis, Fac. Sci., Al Azhar Univ., Egypt. American Society of Testing and Materials (ASTM), 2002. Water environmental technology ‘‘Annual book of ASTM standards, Sec. 11.01 and 11.02, West Conshohocken, U.S.N. Barbecot, F., et al., 2000. Hydrochemical and isotopic characterisation of the Bathonian and Bajocian coastal aquifer of the Caen area (northern France). Applied Geochemistry, 15, 791–805. Cohen, S. D., Ed., 1973. Oxford world atlas: New York, Oxford University Press, 190 p. Collins, W.D., 1923. Graphic representation of analyses. Ind. Eng Chem 15:394. Chadha, D.K., 1999. A proposed new diagram for geochemical classification of natural waters and interpretation of chemical data. Hydrogeol J 7 (5): 431-439. David C. Greene, 1984. Structural geology of the Quseir area, Red Sea coast, Egypt", Department of Geology and Geography, University of Massachusetts Amherst, Massachusetts. Davis, J.C., 1986, Statistics, Data analysis in Geology. Wiley, New York. Duce, R., G. L. Hoffman and W. H. Zoller, 1975. Atmospheric trace metals at remote northern and southern hemi-sphere sites: pollution or natural, Science 187: 339-342. Karmegam, U., S. Chidambaram, P. Sasidhar, R. Manivannan, S. Manikandan, P. Anandhan, 2010, Geochemical characterization of groundwaters of shallow coastal aquifer in and around Kalpakkam, South India. Res Environ Earth Sci 2(4): 170-177. Papatheodorou, G., N. Lambrakis and G.Panagopoulos, 2007. Application of multivariate statistical procedure to the hydrochemical study of a coastal aquifer an example from Crete. Greece Hydrological Processes 21, 1482-1495. Vandenbohede, A., C. Courtens and L. William de Breuk, 2010. Fresh-salt water distribution in the central Belgian coastal plain: an uptate, Geol Belg, 11 (3): 163-172. Parkhurst, D.L. and C.A.J. Appelo, 1999. User’s guide to PHREEQC. A computer program for speciation, batch-reaction, one-dimensional transport, and inverse geochemical calculations: U.S. Geol Surv Water-Resour Investig Rep : 99–4259. Piper, A.M., 1953. A graphical procedure in the Geo-chemical interpretation of water analysis. USGS groundwater note, pp.12. Starinsky A., M. Bielski, B. Lazar, G. Steinitz and M.Raab, 1983. Strontium isotope evidence on the history of oilfield brines, Mediterranean Coastal Plain, Israel. Geochim. Cosmochim. Acta 47,687-695. Zaporozec, A., 1972. Graphical interpretation of water quality data. Groundwater. 10(2): 32-43.

700