S.Y. Chung

Pukyong National University, Korea, Department of Earth & Environmental Sciences, Faculty Member

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I am an Emeritus Professor in the Dept. of Earth Sciences, and interested in groundwater hydrology, AI methods to groundwater contamination vulnerability, and geostatistical applications to groundwater modeling and data estimation. I earned B.S. and M.S. from Seoul National University, Korea and Ph.D. from University of Nevada at Reno, USA. I published over 120 articles in International and Domestic Journals.

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Papers by S.Y. Chung

Novel machine learning algorithms to predict the groundwater vulnerability index to nitrate pollution at two levels of modeling

Chemosphere

The accurate mapping and assessment of groundwater vulnerability index are crucial for the preser... more The accurate mapping and assessment of groundwater vulnerability index are crucial for the preservation of groundwater resources from the possible contamination. In this research, novel intelligent predictive Machine Learning (ML) regression models of k-Neighborhood (KNN), ensemble Extremely Randomized Trees (ERT), and ensemble Bagging regression (BA) at two levels of modeling were utilized to improve DRASTIC-LU model in the Miryang aquifer located in South Korea. The predicted outputs from level 1 (KNN and ERT models) were used as inputs for ensemble bagging (BA) in level 2. The predictive groundwater pollution vulnerability index (GPVI), derived from DRASTIC-LU model was adjusted by NO3–N data and was utilized as the target data of the ML models. Hyperparameters for all models were tuned using a Grid Searching approach to determine the best effective model structures. Various statistical metrics and graphical representations were used to evaluate the superior predictive performance among ML models. Ensemble BA model in level 2 was more precise than standalone KNN and ensemble ERT models in level 1 for predicting GPVI values. Furthermore, the ensemble BA model offered suitable outcomes for the unseen data that could subsequently prevent the overfitting issue in the testing phase. Therefore, ML modeling at two levels could be an excellent approach for the proactive manage-ment of groundwater resources against contamination.

Inferences on metal pollution in the natural spawning zone of Bangladesh river and pollution management strategies

Environmental Monitoring and Assessment

Due to the coagulation and adsorption processes, it was shown that Fe and Zn had a substantial co... more Due to the coagulation and adsorption processes, it was shown that Fe and Zn had a substantial correlation of 0.96, Cu and Cd of 0.91, and Cr of 0.78 with Zn. Hazard quotient values of Cd show the not potable nature of Halda river surface water and might give adverse health effects for all age groups except Cu and Zn. Pollution load index values indicated the uncontaminated nature of the river bottom sediments. Natural and human

A review on global status of fresh and saline groundwater discharge into the ocean

Environmental Monitoring and Assessment

Submarine groundwater discharge (SGD) is the groundwater flow from land to the sea across the sea... more Submarine groundwater discharge (SGD) is the groundwater flow from land to the sea across the seabed, and it includes both terrane freshwater and recirculated seawater in the sub-surface. This review (i) ystematically evaluates findings of various quantification methodologies, (ii) examines the esti-mated SGD in scientific publications between 2000 and 2020, and (iii) quantitatively evaluates current situation of coastal zone management through the bibliometric analysis of research papers. Apart from enhancing the shortage of groundwater resources in coastal area, the SGD brings nutrients (nitrate and phosphate), toxic heavy metals, and organic com-pounds, and thus contaminate the seawater. There-fore, the improved understanding about location and quantity of global SGD is essential to conserve the coastal and ocean ecosystems.

Application of SVR-kernel models for nitrate contamination vulnerability assessment in the shallow aquifer of Miryang City, Korea

Groundwater Contamination in Coastal Aquifers

Hydrogeochemical Survey along the Northern Coastal Region of Ramanathapuram District, Tamilnadu, India

Applied Sciences

Ramanathapuram is a drought-prone southern Indian district that was selected for conducting a hyd... more Ramanathapuram is a drought-prone southern Indian district that was selected for conducting a hydrogeochemical study. Groundwater samples from 40 locations were collected during January 2020 (pandemic interdiction according to COVID) and January 2021. The hydrogeochemical properties of the groundwater samples were evaluated and compared with drinking water regulations to assess their water quality. The order of cation dominance was as follows: Na+ > Ca2+ > K+ > Mg2+ in January 2020 and Na+ > Ca2+ > Mg2+ > K+ in January 2021 with respect to the mean value. The order of anion dominance was as follows: Cl− > HCO3− > SO42− > NO3− > F− in January 2020 and Cl− > SO42− > HCO3− > NO3− > F− in January 2021 with respect to the mean value. In the study area, the southern coastal region was identified as a groundwater-polluted zone through spatial analysis based on all analysis results. The irrigation water quality was analyzed using various calculated ...

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Environmental and Morphological Detrimental Effects of Microplastics on Marine Organisms to Human Health

The ubiquitous presence of microplastics (MPs) in all oceans has become a significant threat to n... more The ubiquitous presence of microplastics (MPs) in all oceans has become a significant threat to nature as global plastic production continues to increase. Now, and over the next 20 to 30 years, it is the time to address the consequences of the rise of the plastic industry global production of millions of items, ranging from a single pen to automobiles. Inappropriate management, lack of awareness of the harmful effects, reckless universal use, and indiscriminate disposal of plastics have turned the earth into a "plastic planet”. The aim of the present study review is to identify the scenarios for the structure, and functions of MPs and the resulting impacts on marine organisms. The different origins of MPs in the oceans and their negative impacts on marine organisms are critically discussed in this review. Due to their small size, these plastic particles are easily ingested by a wide range of marine organisms (e.g., fish, Mollusca, Arthropoda, Annelida, Echinodermata, Nematoda, ...

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Supplement of Missing Data in Groundwater-Level Variations of Peak Type Using Geostatistical Methods

GIS and Geostatistical Techniques for Groundwater Science, 2019

Groundwater-level data of monitoring wells are often missed because of electrical power outage or... more Groundwater-level data of monitoring wells are often missed because of electrical power outage or digital-sensor problems. The missing data need to be interpolated using proper statistical methods, because they degrade the continuity of monitored data. In this study, kriging and conditional simulation were applied for the supplement of the missing groundwater-level data in alluvium and bedrock aquifer with peak type variations. Groundwater-level data of alluvial aquifer were artificially eliminated at the intervals of 10, 20, 40, and 60 days to evaluate the capability of kriging and conditional simulation. Conditional simulation was statistically and graphically superior to kriging in the interpolations of 40 days. Although conditional simulation produced larger statistical errors than kriging in the interpolations of 20 and 60 days, it was more efficient than kriging in producing complicated fluctuations. The interpolated data produced using conditional simulation at the actual missing intervals of a groundwater monitoring well were also reproduced without errors from the original data and represented the fluctuations of original groundwater levels very well. However, conditional simulation has few limitations in the reproduction of fluctuations in the case of a very large missing interval or a very large difference in the data value of a missing interval.

Comparative study of machine learning models for evaluating groundwater vulnerability to nitrate contamination

Ecotoxicology and Environmental Safety, 2022

The accurate evaluation of groundwater contamination vulnerability is essential for the managemen... more The accurate evaluation of groundwater contamination vulnerability is essential for the management and prevention of groundwater contamination in the watershed. In this study, advanced multiple machine learning (ML) models of Radial Basis Neural Networks (RBNN), Support Vector Regression (SVR), and ensemble Random Forest Regression (RFR) were applied to determine the most accurate performance for the evaluation of groundwater contamination vulnerability. Eight vulnerability factors of DRASTIC-L were rated based on the modified DRASTIC model (MDM) and were used as input data. The adjusted vulnerability index (AVI) with nitrate values was used as output data for the modeling process. The performance of three models was verified using the statistical performance criteria of MAE, RMSE, r2, and ROC/AUC values. The ensemble RFR model showed the highest performance in comparison with standalone SVR and RBNN models. Specifically, ensemble RFR kept all promising solutions during the model performance due to its flexibility and robustness, and the vulnerability map obtained by the RFR model was more accurate for predicting the most vulnerable areas to contamination. It was concluded that ensemble RFR was a robust tool to enhance the evaluation of groundwater contamination vulnerability, and that it could contribute to environmental safety against groundwater contamination.

Impacts of Microplastics on Marine Organisms and in Human Health

The ubiquitous presence of microplastics (MPs) across all oceans has emerged as a significant mar... more The ubiquitous presence of microplastics (MPs) across all oceans has emerged as a significant marine hazard as worldwide plastic production continues to grow. Now and during the next 20-30 years will be the time to confront the implications of the plastic industry's rise, which has resulted in the large-scale global production of millions of plastic-based items, varying from a single pen to automobiles. Inappropriate management, lack of awareness of the detrimental effects, reckless universal use, and the indiscriminate disposal of plastic based synthetic materials, has turned Earth into a "plastic planet”. It is critical to have a throughout understanding of MPs' potential from sink to source as well as the processes that govern their distribution and uptake and exchange in ecosystems, to properly comprehend their potential consequences and ecological harm. The goal of the present study was to identify the scenarios of microplastics structure, functions and subsequent ...

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Groundwater decrease and contamination around subway tunnels in a coastal area of Busan City, Korea

Environmental Earth Sciences, 2021

Groundwater decrease and quality deterioration are common phenomena at coastal areas with subway ... more Groundwater decrease and quality deterioration are common phenomena at coastal areas with subway tunnels in the world. This study investigated the problems in Busan Metropolitan City of Korea, using the integrated techniques of hydrogeological, hydro-geochemical, geostatistical, multivariate statistical and isotopic analyses. Groundwater around the subway was heavily discharged, and the groundwater level around the subway was fallen to −25.3 m on basis of mean sea level. The deep drawdown of groundwater level spurred the induction of seawater and salinized river water toward the inland area, and the groundwater was contaminated around the subway. This study identified that groundwater-level largely descended due to the excessive utilization of groundwater and the severe groundwater discharge from the subway tunnels, and that seawater and salinized river water intruded the inland groundwater and contaminated the groundwater around the subway. It is considered that this study will contribute to the investigation for the causes of groundwater decrease and contamination around subway tunnels in the worldwide metropolitan cities as well as the Busan City of Korea.

The Characteristics of Hydrogeological Parameters of Unconsolidated Sediments in the Nakdong River Delta of Busan City, Korea

Journal of Soil and Groundwater Environment, 2017

This study dealt with the characteristics and the interrelations of hydrogeological parameters su... more This study dealt with the characteristics and the interrelations of hydrogeological parameters such as hydraulic conductivity, dispersivity and effective porosity of unconsolidated sediments for providing the basic data necessary for the planning of the management and preservation of groundwater quality in the Nakdong River Delta of Busan City, Korea. Groundwater quality in this area has been deteriorated due to seawater intrusion, agricultural fertilizer and pesticide, industrial wastewater, and contaminated river water. The physical properties (grain size distribution, sediment type, sorting) and aquifer parameters (hydraulic conductivity, effective porosity, longitudinal dispersivity) were determined from grain size analysis, laboratory permeability test and column tracer test. Among 36 samples, there were 18 Sand (S), 7 Gravelly Sand (gS), 5 Silty Sand (zS), 5 Muddy Sand (mS), and 1 Sandy Silt (sZ). Hydraulic conductivity was determined through a falling head test, and ranged from 9.2 × 10 -5 to 2.9 × 10 -2 cm/sec (0.08 to 25.6 m/day). From breakthrough curves, dispersivity was calculated to be 0.35~3.92 cm. Also, effective porosity and average linear velocity were obtained through the column tracer test, and their values were 0.04~0.46 and 1.06E-04~6.49E-02 cm/sec, respectively. Statistical methods were used to understand the interrelations among aquifer parameters of hydraulic conductivity, effective porosity and dispersivity. The relation between dispersivity and hydraulic conductivity or effective porosity considered the sample length, because dispersivity was affected by experimental scale. The relations between dispersivity and hydraulic conductivity or effective porosity were all in inverse proportion for all long and short samples. The reason was because dispersivity was in inverse proportion to the groundwater velocity in case of steady hydrodynamic dispersion coefficient, and groundwater velocity was in proportion to the hydraulic conductivity or effective porosity. This study also elucidated that longitudinal dispersivity was dependent on the scale of column tracer test, and all hydrogeological parameters were low to high values due to the sand quantity of sediments. It is expected that the hydrogeological parameter data of sediments will be very useful for the planning of groundwater management and preservation in the Nakdong River Delta of Busan City, Korea.

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Groundwater pollution index (GPI) and GIS-based appraisal of groundwater quality for drinking and irrigation in coastal aquifers of Tiruchendur, South India

Environmental Science and Pollution Research, 2021

We assessed groundwater pollution index (GPI) and groundwater quality of coastal aquifers from Ti... more We assessed groundwater pollution index (GPI) and groundwater quality of coastal aquifers from Tiruchendur in South India for drinking and irrigation by evaluating the physico-chemical parameters of 35 samples of mainly Na-Cl type in an area of 470 km2 with respect to the World Health Organization (WHO) standard as well as by estimating different indices such as total hardness (TH), sodium percentage (Na%), magnesium ratio (MR), Kelley’s ratio index (KR), potential salinity (PS), Langelier saturation index (LSI), residual sodium carbonate (RSC), sodium adsorption rate (SAR), permeability index (PI), and the irrigation water quality index (IWQI). Minimal influence of aquifer lithology and the dominant influence of evaporation on groundwater chemistry reflected the semi-arid climate of the study area. Electrical conductivity (EC) of about 89% of the samples across 418 km2 exceeded the permissible limit and Ca values of 74% of samples, however, remained within the allowable limit for drinking. More chloride was caused by influx of seawater and salt leaching and higher K was due to excessive fertilizer usage for agriculture. The spatial distribution map created using inverse distance weighting (IDW) method shows that the suitable groundwater is present close to the river basin. GPI values between 0.40 and 4.7, with an average of 1.5, classify insignificant pollution in 43% of the study region and the groundwater suitable for drinking purposes. In addition, 17% of the groundwater samples are also marginally suitable for drinking. The irrigation water quality indices provided contradictory assessments. Indices of TH, Na%, MR, PS, and LSI suggested 32–95% of the samples as unsuitable for irrigation, whereas the indices of RSC, SAR, and PI grouped 72–100% samples as permissible for irrigation. The IWQI map, however, indicated that the groundwater from more than half of the study area are not apt for irrigation and the groundwater of about one-third of the area could only be applied to salt-resistant plants.

Variations of water quality deterioration based on GIS techniques in surface and groundwater resources in and around Vembanad Lake, Kerala, India

Geochemistry, 2020

Abstract This study evaluated the status of deteriorating water quality around the Vembanad Lake ... more Abstract This study evaluated the status of deteriorating water quality around the Vembanad Lake of Kerala State in India. A total of 40 water samples from lake (L, n = 5), river (R, n = 6), open well (W, n = 26), and bore well (BW, n = 9) and were analysed for major ions as per the APHA methods. Different concentrations of Ca (10–190 mg/L), Mg (2–220 mg/L), Na (10–216 mg/L), K (2–50 mg/L), HCO3 (20–400 mg/L), CO3 (10–50 mg/L), Cl (46.5–950 mg/L), NO3 (0.62–19.75 mg/L), SO4 (20.8–423 mg/L) and PO4 (1.63–16.18 mg/L) represent the three different water types: Ca HCO3, Na Cl and mixed type of Ca Na HCO3. Strong connection between the host rock and groundwater quality indicated substantial water-rock interaction. Factor analysis helped to understand the associations of chemical parameters and their sources. TDS, TH, calcium, magnesium, sodium, potassium and chloride exceeded the BIS (2010) based on desirable drinking water and irrigational quality standards in SE, W, and NW directions due to man-made bunds, industrial wastes, agricultural wastes, household sewages, tourism, lime shell, and sand mining. All point and non-point sources of pollution adversely affected water in and around the Vembanad Lake system and caused by water quality deterioration.

Processes and characteristics of hydrogeochemical variations between unconfined and confined aquifer systems: a case study of the Nakdong River Basin in Busan City, Korea

Environmental Science and Pollution Research, 2020

This study is to assess the hydrogeochemical characteristics of groundwater at the deltaic region... more This study is to assess the hydrogeochemical characteristics of groundwater at the deltaic region of the Nakdong River Basin in the Busan Metropolitan City of Korea. The study area is covered by the Quaternary sedimentary deposits and the Cretaceous granites associated with unconformity. The thick sedimentary deposits consists of two aquifers, i.e., unconfined and confined aquifers on the basis of clay deposit. Groundwater samples were collected from seven boreholes: two from unconfined aquifer and five from confined aquifer systems during the wet season of 2017 year. ORP and DO indicates that the groundwater of the unconfined aquifer exists in the oxidization condition and that of the confined aquifer pertains in the reduction condition. Piper’s trilinear diagram shows CaSO 4 type for groundwater of the unconfined aquifer, and NaCl type for that of the confined aquifer. Ionic concentrations of groundwater increase in the confined aquifer because of direct and reverse ion exchange processes. Carbonate weathering and evaporation are other mechanisms in the water-rock interaction. Saturation indices of dolomite and calcite are observed as oversaturated, while halite reveals undersaturation. Hierarchical cluster analysis (HCA) exhibits that cluster 1 and cluster 2 represents the properties of groundwater in unconfined and confined aquifers, respectively. Factor analysis shows that groundwater of the confined aquifer is much influenced by seawater, and includes heavy metals of iron and aluminum. Groundwater samples in unconfined and confined aquifers are located at the rock weathering and evaporation zones in the Gibbs diagram. Inverse geochemical modeling of PHREEQC code suggests that carbonate dissolution and ion exchange of major ions are the prevailing geochemical processes. This comprehensive research provides the distinguished hydrogeochemical characteristics of groundwater in confined and unconfined aquifer systems of the Nakdong River Basin in Busan City, Korea.

GIS and Geostatistical Techniques for Groundwater Science

GIS and Geostatistical Techniques for Groundwater Science, 2019

Lithofacies modeling of Late Jurassic in upper Ulayyah reservoir unit at central Saudi Arabia with inference of reservoir characterization

Journal of Petroleum Science and Engineering, 2019

Abstract Saudi Arabia is reported to have an extensive hydrocarbon potential in the carbonates of... more Abstract Saudi Arabia is reported to have an extensive hydrocarbon potential in the carbonates of Jurassic age. This has been proved by several studies considering their economic significance. These studies focused mainly on the petroleum related research. However, there were few studies about the reservoir characteristics focusing on the sedimentology and the micro paleontology. But still a detailed study is essential to develop a clear insight on the stratigraphic relationship between the reservoir, their sedimentological characters and their non-homogeneity between the wells of the individual oil fields. This study aims to establish 3-D geo-cellular stochastic models of the lithofacies to characterize the reservoir geometries, architecture and heterogeneity of a formation similar to the late Jurassic (Oxfordian-Kimmeridgian age). The central Saudi Arabia is represented by the late uppermost Ulayyah reservoir a representative of Hanifa Formation. The study attempts an integrated approach considering high resolution sediment analysis, spatial continuity of semi-variogram and 3-D geostatistical facies modeling. The outcrop strata consist mostly of grainstone, medium to thick limestone with different skeletal remains of foraminifera, bivalve, brachiopods stramatoporoid, corals and echinoderms. They also consist of non-skeletal components like ooids, peloids and intraclasts. The outcrop facies analysis revealed that the depositional environment ranges from relatively Outer ramp, Middle ramp and Inner ramp. The major axis of variograms (N-S) represent the lithofacies with good continuity (high degree of continuity) at the outcrop of the upper Ulayyah member. Minor axis (E-W) depicts poor continuity. The variogram of the lithofacies reflects a minor tendency of geometrical anisotropy. The geometry and architecture of the facies stacking pattern presented a genetics correlation with the variogram parameters at the outcrop scale. The 3-D model at low resolution reveals the existence of layer cake pattern. Subsequently at higher resolution a greater extent of non-homogeneity exists. Outcrop analogue of the uppermost Ulayyah reservoir equivalent is perfect for developing and understanding their basic geometry. This study will also help to get an insight into the distribution of petrophysical properties (e.g., porosity and permeability) along with the horizontal details of well spacing that might help to improve field appraisal and towards planning and development.

Time series analyses of hydrological parameter variations and their correlations at a coastal area in Busan, South Korea

Hydrogeology Journal, 2018

Monitoring and time-series analysis of the hydrological parameters electrical conductivity (EC), ... more Monitoring and time-series analysis of the hydrological parameters electrical conductivity (EC), water pressure, precipitation and tide were carried out, to understand the characteristics of the parameter variations and their correlations at a coastal area in Busan, South Korea. The monitoring data were collected at a sharp interface between freshwater and saline water at the depth of 25 m below ground. Two well-logging profiles showed that seawater intrusion has largely expanded (progressed inland), and has greatly affected the groundwater quality in a coastal aquifer of tuffaceous sedimentary rock over a 9-year period. According to the time series analyses, the periodograms of the hydrological parameters present very similar trends to the power spectral densities (PSD) of the hydrological parameters. Autocorrelation functions (ACF) and partial autocorrelation functions (PACF) of the hydrological parameters were produced to evaluate their self-correlations. The ACFs of all hydrologic parameters showed very good correlation over the entire time lag, but the PACF revealed that the correlations were good only at time lag 1. Crosscorrelation functions (CCF) were used to evaluate the correlations between the hydrological parameters and the characteristics of seawater intrusion in the coastal aquifer system. The CCFs showed that EC had a close relationship with water pressure and precipitation rather than tide. The CCFs of water pressure with tide and precipitation were in inverse proportion, and the CCF of water pressure with precipitation was larger than that with tide.

Source and remediation for heavy metals of soils at an iron mine of Ulsan City, Korea

Arabian Journal of Geosciences, 2018

Ulsan mine produced the iron ore minerals of magnetite, arsenopyrite, and scheelite in 1992, and ... more Ulsan mine produced the iron ore minerals of magnetite, arsenopyrite, and scheelite in 1992, and serpentine was developed from 1977 to 2002. The soils of the mine were contaminated by heavy metals such as As, Zn, Ni, and Cd. Heavy metals of Ni and Zn came mostly from serpentinite, and As was derived mainly from arsenopyrite in the scan-type iron ore body. As, Zn, and Ni were major contaminants, but Cd was a minor contaminant on a basis of Korean standard. The heavy metals in the deep depth (> 5 m) came from the host rocks, and those in the shallow depth (< 5 m) were derived from the organic–mineral complexation soil. The remediation plan was a soil washing for highly contaminated soils and the containment of clay materials for less contaminated soils. Even though the remediation methods were successful, the continuous monitoring and the analysis of monitoring data are still necessary for the conservation of soil and groundwater around the study area.

Interrelationship between geochemical elements of sediment and groundwater at Samrak Park Delta of Nakdong River Basin in Korea: multivariate statistical analyses and artificial neural network approaches

Environmental Earth Sciences, 2017

This research was conducted at Samrak Park Delta of Nakdong River Basin in Busan Metropolitan Cit... more This research was conducted at Samrak Park Delta of Nakdong River Basin in Busan Metropolitan City, Korea. The main objective of this study was to evaluate the interrelationship of geochemical elements in sediments and groundwater through multivariate statistical analyses and a multilayer perceptron artificial neural network model. The mean concentrations of chemical elements were Si (46%), Fe (16.9%), Al (15.7%), K (7.5%) and Ca (4.5%) in sediments, and Na (8650 mg/L), Mg (999 mg/L), Ca (432 mg/L), K (293 mg/L) and Cl (17,640 mg/L) in groundwater, respectively. The principal component analysis produced 3 kinds of factors with the variances of 63.37, 27.02 and 9.62%, respectively. It is suggested that the chemical components of sediments and groundwater were mainly originated from source rocks and seawater intrusion, with the minor impacts of irrigation and industry. Cluster analysis also showed that chemical elements were mainly controlled by the natural geogenic sources and seawater intrusion. Multilayer perceptron of artificial neural network (ANN) presented the good interrelationship between sediment and groundwater. The determination coefficients (R2) between ANN predicted values and observed values in groundwater showed the high values of 0.61–0.97 except Mg, Mn and Sr. It is revealed that the chemical components of sediment and groundwater were derived from local geological origin and from the minor impact of anthropogenic sources. Multivariate analyses and ANN contributed to the identification of the mutual relationship between the geochemical elements of sediment and those of groundwater.

Evaluation of physico-chemical parameters in water and total heavy metals in sediments at Nakdong River Basin, Korea

Environmental Earth Sciences, 2015

Fourteen water and sediment samples were collected from the Nakdong River Basin in Korea to evalu... more Fourteen water and sediment samples were collected from the Nakdong River Basin in Korea to evaluate the physico-chemical parameters (pH, dissolved oxygen, chemical oxygen demand, biological oxygen demand, total organic carbon) in water and total heavy metals (Cu, Zn, Pb, Cd, As) in surface sediments. The assessment of physico-chemical parameters indicates that river water and sediments in the study area were strongly impacted by industrial wastewater, irrigational effluents and domestic sewage. The overall average concentrations of metals in sediments were Cu (6.41 mg/kg), Cd (0.11 mg/kg), Pb (4.72 mg/kg), Zn (16.8 mg/kg), As (0.19 mg/kg), and the order of the concentrations was Zn > Cu > Pb > As > Cd. Geo-accumulation index (Igeo) indicates that most of samples fall at unpolluted to medium category, while contamination factor values fall at the medium to very high pollution zone. Pollution load index also suggests that all samples fall at progressive pollution sector. Multivariate statistical analysis and pollution index methods were helpful for the classification on the basis of the contamination sources and origin of heavy metals. In conclusion, this study clearly infers the fact that the cause of metal pollution in this region is mainly due to the effluents discharged from factories, agricultural fields and sewers.

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