Drinking Groundwater Research Articles

Application of Geophysical and Hydrogeochemical Methods to the Protection of Drinking Groundwater in Karst Regions.

To provide theoretical support for the protection of centralized drinking groundwater sources in karst areas, it is necessary to accurately identify the development of karst conduits and analyze the differences in hydrogeochemical characteristics of different karst systems. This provides a scientific basis for the accurate designation of risk zones that may cause drinking groundwater pollution. In this study, a geophysical survey, hydrogeological chemical process analysis and optimized fuzzy cluster analysis were used to gradually improve the understanding of karst water systems. AMT and HDR methods were used to calibrate the resistivity around the water-filling karst conduits, which ranged from 39 to 100 Ω·m. A total of seven karst systems were identified, including four karst systems in the north of the study area, one karst system in the west and two karst systems in the south. Analysis of the hydrochemical data showed that HCO3-Ca and HCO3-Mg-Ca types accounted for 90% of all samples. The δD and δ18O values of their main conduits were −51.70‰ to −38.30‰ and −7.99‰ to −5.96‰, respectively. The optimized fuzzy clustering analysis method based on the weight of variables assigned by AHP more accurately verified karst water systems. Based on these findings, the drinking groundwater source risk zone was designated with an area of 33.90 km2, accounting for 34.5% of the study area. This study effectively improved the rationality and accuracy of the designation of drinking groundwater source risk zones in karst areas, and provided a scientific basis for the identification of karst water systems and decision-making of drinking groundwater source protection in karst areas.

Assessment of Major and Trace Elements in Drinking Groundwater in Bisha Area, Saudi Arabia

Drinking groundwater represents 30% of the world’s fresh water and 0.9% of the whole world’s water. Therefore, routine analysis and monitoring of the groundwater is a paramount issue, specifically the measurement of elemental concentrations due to aquifer characterization. Consequently, the purpose of this study was to determine major and trace elements in groundwater. In total, 25 samples of groundwater were collected from wells in the Bisha area, Asir province, Saudi Arabia. All samples were analyzed for major and trace elements by using Inductively Coupled Plasma Mass Spectrometry (ICP-MS). In total, 15 elements were measured including four major elements (Na, K, Mg, and Ca) and 11 trace elements (V, Cr, Mn, Co, Ni, Cu, Zn, As, Se, Cd, and Pb). Major elements (Na, Mg, and Ca) exceeded the guideline limits in some samples. In addition, only one trace element (Se) exceeded the World Health Organization (WHO) permissible limits in some samples. This could be due to rock characteristics in aquifers. Very hard water was shown in 92% of the samples. Moreover, a high percentage (32%) of the analyzed samples also exceeded the guideline levels for chloride. ANOVA analysis showed significant difference (p<0.05) between Bisha samples (North and South), Bisha samples (North), and the remaining samples, for V and pH, and Na, Cl−, EC, and TDS, respectively. No significant differences (p>0.05) were reported for Na, K, Mg, Ca, Cr, Mn, Co, Ni, Cu, Zn, As, Se, Cd, and Pb between all samples. In general, 25 significant (p>0.05) correlations were reported among the measured elements. For the positive correlations, similar distribution for the elements is anticipated. In conclusion, the groundwater in this study is not suitable for domestic use due to its hardness and only some are suitable for irrigation. More studies are needed to confirm our findings in the study area.

Evaluation of potable groundwater zones identification based on WQI and GIS techniques in Adyar River basin, Chennai, Tamilnadu, India

The main objective of this study is to identify the potable groundwater zones in Adyar River Basin (ARB) that forms the major river of Chennai metropolitan and significantly contributes to the demands of this big city's water supply. Twenty eight groundwater samples were collected during postmonsoon and premonsoon seasons in 2016 from the wells of ARB which is downstream of Chembarambakkam Lake, which supplies drinking water to Chennai metropolitan city. All the water samples were analyzed using Portable meter and Ion Chromatography for physico-chemical parameters and major ions such as pH, TDS, Ca, Mg, Na, K, Cl, HCO3, SO4 and NO3. The analytical results were compared with the WHO, USEPA & BIS guideline values and reported that some of the samples exceeds these guideline values for drinking water quality. Spatial distribution maps were prepared to identify the potable groundwater available regions based on these water quality parameters. Piper and Gibbs plots are generated to identify the nature and type of groundwater with processes controls the groundwater chemistry. Principal component analysis was done to interpret the possible sources of chemical compounds present in the groundwater. To precisely delineate the potable groundwater region in ARB, Water Quality Index (WQI) approach is employed with the basic water quality parameters and spatial distribution maps were prepared using GIS for the obtained indexes. It is found that only 10.71% and 17.86% of the study area groundwater is within the excellent water quality for drinking during postmonsoon and premonsoon respectively, whereas 42.86% in postmonsoon and 14.29% in premonsoon is found as poor quality groundwater for drinking. The groundwater of the northwestern and western part of ARB is under very poor and unsuitable category for drinking in both the seasons. This region of ARB is recommended for implementation of artificial groundwater recharging to improve the groundwater quality and make it suitable for drinking.

Hydrochemical studies and evaluation of groundwater quality of the Quaternary aquifer at Faquss, Al Sharqiya Governorate, Egypt

The Quaternary deposits represent the main groundwater aquifer in the study area. During the last few years, the problem of groundwater contamination has been intensified mainly due to natural and human-related factors. The present work aims to study the hydrochemical characteristics and quality assessment of shallow groundwater of the Quaternary aquifer at Faquss district. To achieve that, 16 groundwater samples were collected and analyzed for major ions, trace elements, and microbiological analysis. Constructions of water level map of the Pleistocene aquifer and distribution maps for different ions in groundwater were made by surfer software. Statistical analyses for water quality parameters were carried out. Results indicate that most of the studied area is characterized by fresh water (TDS < 1000 mg/L) with low contents of K, Na, Mg, Ca, SO4, and Cl reflecting the suitability of ground water for drinking. High contents of TDS, Na, SO4, and Cl are recorded at the northeastern parts of the area; this refers to the existence of local pollution sources resulting from the infiltration of domestic, agricultural, and industrial wastes in the intensive populated area. The concentrations of trace elements (chromium, copper, cadmium, etc.) in groundwater are within the acceptable limits for drinking and domestic uses. Iron and manganese are over the acceptable limits in most of the area and the groundwater is unsuitable for drinking. Low contents of iron and manganese are recorded at the north, while aluminum contents are over the acceptable limits at the same site. The results of bacteriological analyses indicate the existence of E. coli bacteria in most of shallow wells ranges between 4 and 800 ml. So, shallow groundwater should be chemically treated before drinking. Generally, the groundwater in the studied area is suitable for irrigation, except 19% of wells suffer from sodium hazards. The ratio rNa/rCl varies between 1.012 and 1.56 in most groundwater samples and indicates the continental origin of groundwater in the study area. The ratio r (K + Na)-rCl/rSO4 reflects either Na2–SO4 water type (in 75% of groundwater samples) or NaHCO3 water type of shallow meteoric origin (in 25% of groundwater samples). The presence of Na2SO4 water type in deep meteoric water genesis at shallow depth is associated with sulfate salts (MgSO4, and CaSO4) which formed more than 25% of salt combination might reflect the influence of anthropogenic activities. The dominant process determining the water composition is evaporation.

Evaluation of groundwater quality for drinking purposes: a case study from the Beheshtabad Basin, Chaharmahal and Bakhtiari Province, Iran

Groundwater quality monitoring is of great importance in Iran’s arid and semi-arid regions where water scarcity exists. This study assessed background information on groundwater quality and heavy metals concentration in the spring water of the Beheshtabad Basin, located in Chaharmahal and Bakhtiari Province, Iran, to examine the suitability of the groundwater for drinking. Groundwater samples were collected from five springs in the basin during the time frame of February 2014 and September 2015 and analyzed in terms of physicochemical characteristics such as pH, electrical conductivity (EC), total dissolved solids (TDS), cations, anions, and heavy metal concentration. These parameters were used to determine the groundwater’s suitability for domestic purposes by comparing their measured values to the maximum permissible limits according to recommendations of the World Health Organization. The results revealed that most groundwater samples are suitable for drinking. During the rainy season, however, spring waters are bacteriologically contaminated and unsuitable for human consumption. As important parameters for determining drinking water quality, water quality index (WQI) values in the present study indicated very poor quality water for some groundwater samples in the area dominated by weathering of rocks and dissolution of salts from the bedrock into the water resources, which can be a serious threat to the ecological habitat.

Оценка современного состояния ресурсной базы пресных подземных вод южных районов Республики Коми

The state of the resource base of fresh underground waters of the southern regions of the Komi Republic (RK) is assessed. The distribution of groundwater reserves by the administrative-territorial objects of the south of the Komi Republic, by geological and hydrogeological structures, by 83 explored deposits of drinking and industrial groundwater is analyzed. The volumes of groundwater production in 2019 are given. A low degree of development of the resource potential and groundwater reserves is noted. The degree of development of reserves does not exceed 6 %. The degree of knowledge of groundwater is 1 %. The aquifers (horizons) of fresh groundwater of the research area are characterized.

Drinking Desalinated Water that Lack Calcium and Magnesium Has No Effect on Mineral Content of Enamel and Dentin in Primary Teeth.

Objective: The present study compared the mineral contents of enamel and dentin of primary teeth from children exposed to desalinated water with those from children drinking ground water. Study design: The study comprised of two groups of teeth, seven primary teeth from children living in areas supplied exclusively with desalinated water and seven primary teeth from children that have been exposed solely to ground water from in-utero until the teeth were either extracted or naturally shed. Mineral content of three tooth regions was determined by scanning electron microscopy with an energy dispersive X-ray spectrometer (EDS). The main ion content of each region was calculated. Results: Children exposed to ground water presented higher levels of magnesium in pre- and post- natal enamel than children living in areas supplied exclusively with desalinated water but without significant differences. The same was found for calcium levels. Excluding post-natal enamel calcium level (of borderline statistical significance), no significant differences were found in magnesium and calcium levels of primary teeth enamel and dentin of children exposed to desalinated water in comparison to children exposed to ground water. Conclusion: Mineral content of enamel and dentin in primary teeth is not affected by consuming desalinated water.

Effect of Micronutrient Powder (MNP) with a Low-Dose of Iron on Hemoglobin and Iron Biomarkers, and Its Effect on Morbidities in Rural Bangladeshi Children Drinking Groundwater with a High-Level of Iron: A Randomized Controlled Trial.

Micronutrient Powder (MNP) is beneficial to control anemia, but some iron-related side-effects are common. A high level of iron in the groundwater used for drinking may exacerbate the side-effects among MNP users. We conducted a randomized controlled trial examining the effect of a low-dose iron MNP compared with the standard MNP in children aged 2–5 years residing in a high-groundwater-iron area in rural Bangladesh. We randomized 327 children, who were drinking from the “high-iron” wells (≥2 mg/L), to receive either standard (12.5 mg iron) or low-dose iron (5.0 mg iron) MNP, one sachet per day for two months. Iron parameters were measured both at baseline and end-point. The children were monitored weekly for morbidities. A generalized linear model was used to determine the treatment effect of the low-dose iron MNP. Poisson regressions were used to determine the incidence rate ratios of the morbidities. The trial was registered at ISRCTN60058115. Changes in the prevalence of anemia (defined as a hemoglobin level < 11.0 g/dL) were 5.4% (baseline) to 1.0% (end-point) in the standard MNP; and 5.8% (baseline) to 2.5% (end-point) in the low-dose iron MNP groups. The low-dose iron MNP was non-inferior to the standard MNP on hemoglobin outcome (β = −0.14, 95% CI: −0.30, 0.013; p = 0.07). It resulted in a lower incidence of diarrhea (IRR = 0.29, p = 0.01, 95% CI: 0.11–0.77), nausea (IRR = 0.24, p = 0.002, 95% CI: 0.09–0.59) and fever (IRR = 0.26, p < 0.001, 95% CI: 0.15–0.43) compared to the standard MNP. Low-dose iron MNP was non-inferior to the standard MNP in preventing anemia yet demonstrated an added advantage of lowering the key side-effects.

Multivariate Investigation of Heavy Metals in the Groundwater for Irrigation and Drinking in Garautha Tehsil, Jhansi District, India

Groundwater is an important source for drinking and irrigation purposes. Due to anthropogenic activities, heavy metals have been leaching due to industrial waste and agricultural activities to the groundwater causing pollution. The assessment of groundwater quality is necessary to reduce the pollution to acceptable levels. Therefore, the aim of this study is to investigate heavy metal concentrations in the groundwater of the villages of Garautha Tehsil, Jhansi where the anthropogenic activities are active. The groundwater samples were analyzed by inductively coupled plasma – mass spectrometry (ICP-MS) and the results were compared to the 2012 Bureau of Indian Standard limits. Three multivariate statistical methods were used to analyze the groundwater quality for irrigation and drinking purposes and to investigate the geological and hydrogeological processes. The results of principal component analysis (PCA) identified four factors responsible for the data structure by illuminating the total variance of 77.83% of the dataset. The majority of groundwater samples contained Al, Co, Cu, Mn, Ni, Cr, Pb, and Fe within the acceptable limits except at few locations. However, the Al, Fe, and Mn concentration were high at a few sites due to rock–water interactions, whereas the concentration of As, Cd, and Zn were lower than their respective permissible limits in all groundwater samples. Furthermore, the groundwater quality for the use of irrigation is found to be acceptable at 19 locations, with only one high result.

Hydrogeochemistry of High Fluoride Groundwater to Understand the Suitability of Groundwater for Drinking and Irrigation Purposes in Granulite Belt Part of Bhopalpatnam Area, Bijapur District, Chhattisgarh, India

Present study describes the hydrogeochemistry of Bijapur district, Chhattisgarh, with the aim to understand fluoride concentration by geochemical behavior of groundwater, from recharge to discharge through factors such as rock weathering, aquifer lithology, cation exchange etc. Sixty-two representative groundwater samples from Bijapur District were collected during two different seasons pre-monsoon and post-monsoon (2016) and analyzed for major cations and anions. Results clearly demonstrate that the seasonal effect imposes a serious impact on the concentration of ions due to the dilution of water in pre-monsoon and post-monsoon seasons. High concentration of fluoride is observed during pre-monsoon (3.58 mg/L) and post-monsoon (3.12 mg/L) periods which are higher than the BIS permissible limit i.e. 1.5 mg/L. Gibbs diagram shows rock-water interaction dominance and evaporation dominance, which are responsible for the change in the quality of water in hard rock aquifer of the study area. Suitability of groundwater for drinking and irrigation purpose also assessed this study. Considering the findings from the present study, the study area needs special attention to ensure the supply of potable water to maintain sustainable life.

Groundwater as a Source of Drinking Water in Southeast Asia and the Pacific: A Multi-Country Review of Current Reliance and Resource Concerns

Groundwater is widely acknowledged to be an important source of drinking water in low-income regions, and it, therefore, plays a critical role in the realization of the human right to water. However, the proportion of households using groundwater compared with other sources is rarely quantified, with national and global datasets more focused on facilities—rather than resources—used. This is a significant gap in knowledge, particularly in light of efforts to expand water services in line with the inclusive and integrated agenda of the Sustainable Development Goals. Understanding the prevalence of groundwater reliance for drinking is critical for those involved in water services planning and management, so they can better monitor and advocate for management of water resources that supports sustainable services for households. This paper contributes data that can be used to strengthen the integration of resource considerations within water service delivery and inform the work of development partners supporting this area. We approach this issue from two perspectives. Firstly, we collate data on the proportion of households using groundwater as their primary drinking water source for 10 Southeast Asian and Pacific nations, finding an average of 66% (range of 17–93% for individual countries) of households in urban areas and 60% (range of 22–95%) of households in rural areas rely on groundwater for drinking. Together, these constitute 79% of the total population across the case study countries. Secondly, we review current and emerging groundwater resource concerns within each country, using a systems thinking approach to assess how groundwater resource issues influence household water services. Findings support the case for governments and development agencies to strengthen engagement with groundwater resource management as foundational for achieving sustainable water services for all.

Response of groundwater contamination hazard rating systems to variations in subsoil conditions beneath municipal solid waste (MSW) dumps in developing countries

Groundwater hazard rating systems are generally based on source-pathway-receptor approach. This study determines the response of rating system to the variations in subsurface conditions (generally designated as pathway component). Besides, the study also investigates the ability of the rating systems to respond to the changes in other components too (i.e., source and receptor components). For the purpose, three groups of sites with various combinations of site conditions, that may be encountered in the field, are employed, e.g., a smaller site located in sandy soil with receptors all around it using groundwater or a larger site having a thick clay layer underneath it and the receptors in vicinity using groundwater for drinking. For the analysis, four sets of corresponding rating scores are determined in this study from the selected eleven rating systems (ten earlier rating systems and mGW-HARS, a recently developed system). The investigation shows that mGW-HARAS performs the best for the three sets; for the remaining one set, the performance of mGW-HARAS is marginally lower than its predecessor, GW-HARAS. The sensitivity analysis of the selected rating systems with respect to four critical pathway parameters depicts that mGW-HARAS is sensitive to all the four parameters and has the highest sensitivity to soil permeability, i.e., 83% amongst all the selected rating systems. When these rating systems are applied to ten waste dumps from Indian cities, only one system, i.e., mGW-HARAS, is able to categorize these waste dumps in four hazard categories and responds suitably to the subsurface conditions encountered at these waste dumps.

Field demonstration of solar-powered electrocoagulation water treatment system for purifying groundwater contaminated by both total coliforms and arsenic

ABSTRACT People who drink groundwater in rural areas of Southeast Asia are exposed to pathogens and arsenic (As)-related health problems. A water treatment system consisting of electrocoagulation reactors, using iron (Fe) electrodes and a filtration tank, was designed to treat complex contaminated groundwater for drinking. Its applicability was demonstrated near the Red River in Vietnam. The water treatment system reduced 10.3 CFU/mL of total coliform and 376 μg/L of As(III) in the groundwater to 0 CFU/mL and 6.68 μg/L, respectively. Total coliforms were attenuated by Fe(II) infiltration or enmeshed during Fe precipitate formation. Of the total As, 43% formed As(III) complexation with the Fe precipitates and the other 57% was oxidized to As(V) then adsorbed to Fe precipitates. The Fe precipitates, containing total coliforms and As, were separated from the discharge water in the filtration tank. The system required 49 W of power to operate, which equates to 423 kWh/year, to continuously purify 0.5 t water/day. This requirement was powered by a 380–750 W solar panel, without external energy supply, making the water treatment system an appropriate option for addressing drinking water problems in rural areas.

Distribution of radon and risk assessment of its radiation dose in groundwater drinking for village people nearby the W-polymetallic metallogenic district at Dongpo in southern Hunan province, China

Radon in the household water (especially groundwater) which is an important source of indoor radon, has become a potential health hazard to residents. In this study, radon concentrations in groundwater sampled from five villages near Dongpo W-polymetallic metallogenic region were measured using RAD-7 detector with RAD H2O accessory, and the effect of regional geology and mineralization on radon concentration in groundwater was studied. In addition, we also estimated the radiation doses received by people via ingestion of radon in water and inhalation of the radon from the indoor air while using water. The results show that the radon concentration in groundwater samples varies from 1.29 Bq L−1 to 31.31 Bq L−1 with 10.47 Bq L−1 on average, and about 31.3% of the groundwater samples analyzed have a higher radon concentration than the maximum contaminant level of 11.1 Bq L−1 recommended by United States Environmental Protection Agency (USEPA). The relatively high radon level in groundwater can be attributed to a relatively high uranium background produced by the magmatic activity and magmatic-hydrothermal system. The values of annual effective dose (AEDing) due to ingestion of radon in groundwater range from 0.002 mSv y−1 to 0.055 mSv y−1, 0.005 mSv y−1 to 0.11 mSv y−1 and 0.008 mSv y−1 to 0.188 mSv y−1 for adult, child and infant respectively. The values of annual effective dose due to the inhalation of radon released from water are 63.6, 15.4 and 3.8 times of those through the ingestion of radon in groundwater by the adults, children and infants, respectively. In addition, the values of estimated total annual effective doses are 0.020–0.480 mSv y−1, 0.017–0.406 mSv y−1 and 0.020–0.484 mSv y−1 for adult, child and infant, respectively. These values are much lower than the reference dose level of 1 mSv y−1 recommended by World Health Organization (WHO) and United Nations Scientific Committee on the Effect of Atomic Radiation (UNSCEAR).

Assessment of the Nutrients in the Leachate and the Groundwater Quality for Drinking and Farming around the Nkolfoulou Landfill in Yaoundé, Cameroon

This study focuses on the assessment of the nutrients in the leachate and the groundwater quality around the Nkolfoulou landfill in Yaoundé known in French as “Centre de Traitement de Déchets (CTD).” Landfilling generates leachate that can pollute groundwater. Leachate along with groundwater samples (n=1+13) was collected in January (long dry season) and May (long wet season) 2014 and explored for various parameters including pH, temperature, EC, turbidity, TDS, TA, TSS, TH, BOD5, COD, Na+, K+, Mg2+, Ca2+, NH4+, NO3−, Cl−, F−, SO42−, PO43−, HCO3−, and colour using standard methods. In the leachate samples, values of TSS (700.2 and 130.2 mg/L), BOD5 (140 mg/L), COD (1350 and 1750 mg/L), NH4+ (82.50 and 39.51 mg/L), NO3− (159.32 and 74.82 mg/L), and Cl− (702.69 and 345.50 mg/L) exceeded the Cameroonian standards for effluent discharge. All the values of pH and some values of turbidity (4.55 and 4.50 NTU) and NH4+ (0.51 and 0.73 mg/L) in the groundwater samples violated the Cameroonian standards for drinking water. Based on the water quality index (WQI), an average of 11.53% of groundwater samples was improper for drinking in both seasons. Based on the parameters assessed, all the samples complied with the standard set for irrigation, poultry, and livestock. The hazard quotient (HQ) and the hazard index (HI) of NO3− and F− for children and adults were &lt;1, and hence, the increased non-cancer risks due to these ions through the drinking of groundwater was low. From the statistical analysis, the Nkolfoulou landfill may not be the main source of major ions to the nearby groundwater.

A Review of Metal oxide Nanomaterials for Fluoride decontamination from Water Environment

Abstract Fluoride pollution in water emerges a challenging problem to environmental researchers especially in regions where people depend on groundwater for drinking. Natural water bodies are experienced Fluoride impurities from geogenic and anthropogenic sources. Fluoride contamination in drinking water sources has been recognized as a major problem in many countries worldwide especially in several parts of India, China, Sri Lanka, South Africa, Tanzania, Argentina, East Africa, part of South Africa, Turkey and some part of South America. Intrusion of Fluoride with drinking water manifests several health effects such as dental caries and teeth mottling besides skeletal fluorosis. Due to clinical manifestations caused by drinking Fluoride contaminated water, the World Health Organization (WHO) has recommended 1.5 mg L-1. Hence, it is very much needed to supply water with safe F¯. Various physico-chemical methods are available for defluoridation of water, out of which adsorption method is common and widely be used .to remove fluoride from water. Till date, activated alumina is most conventional adsorbing material that are conveniently being used for this purpose. However, activated alumina performed well in acidic environment and regeneration issue poses a complex problem. Other traditional adsorbents though are able to uptake Fluoride from water environment the low sorption capacities and efficiencies restricted their wide application. A major breakthrough took place in recent years due to application of nanomaterial in water purification. As compared with traditional materials used, nanostructure based adsorbents exhibited much higher performance and efficiency of water decontamination as well as providing a sustainable approach to safe water supply. Nonmaterial is being used throughout the globe as possible solution for removal of fluoride from water as an engineering tool. In the past ten years, many researchers have dealt with low cost and effective adsorbent nanomaterials for the removal of fluoride from aqueous solution and contaminated water. Among them Iron, Magnesia, Alumina, Cerium and calcium, Titania, Silica and Zirconium based metal oxide nanomaterials and composites have proven themselves as excellent adsorbents due to their unique features. The increased surface area of the metal oxide nanoparticles highly favours fluoride adsorption. Their high adsorption capacity, non-toxic nature, limited solubility in water and good desorption potential makes metal oxides a material of choice. The present paper discusses use of nanomaterial and composite nanomaterials for enhanced removal of fluoride contaminated water. The present study also highlights the various key factors (pH, agitation time, initial fluoride concentration, temperature, particle size, surface area, etc) which governs efficacy of different materials in the removal of fluoride from water.

Health Risk Assessment of Inorganic Arsenic Through Groundwater Drinking Pathway in some Agricultural Districts of Hamedan, West of Iran

Groundwater resources are an important portion of potable water in Hamedan Province, Iran. Therefore, monitoring the pollutants especially heavy metals in these resources are vital to protect the residents’ health. This study aimed to assess the health risks caused by inorganic arsenic pollution through groundwater drinking pathway in four important agricultural areas of Hamedan Province, Iran. In so doing, a total of 180 groundwater wells were chosen randomly for sampling during the spring and summer seasons in 2015. The samples were filtered (0.45 μm), preserved with HNO3 at a pH level lower than 2, and stored in acid-washed polyethylene bottles at 4°C for further analysis. Finally, arsenic content was determined using inductively coupled plasma- optical emission spectrometry (ICP-OES). The results showed that the mean contents of arsenic (mg/L) in groundwater samples taken during the spring were 0.052 for Asadabad plain, 0.007 for Ghahavand plain, 0.006 for Razan plain, and 0.004 for Toyserkan Plain; whereas, the mean content in groundwater samples taken during the summer from Asadabad, Ghahavand, Razan, and Toyserkan plains were 0.058, 0.009, 0.007, and 0.004, respectively. Moreover, based on the computed values of the noncarcinogenic risk of groundwater samples from Asadabad plain, the hazard quotient (HQ) was greater than 1. Therefore, a non-carcinogenic effect is considered to be possible for the inhabitants of this study area. Accordingly, serious considerations including managing the use of agricultural inputs especially arsenical pesticides or herbicides and treatment of arsenic-contaminated groundwater with some proper methods before water ingestion are recommended.

Chromium and fluoride contamination in groundwater around leather tanning industries in southern India: Implications from stable isotopic ratio δ53Cr/δ52Cr, geochemical and geostatistical modelling

This study investigates the contamination of groundwater by chromium and fluoride around leather tanning industries. Major ions, chromium, δ53Cr/δ52Cr and fluoride were analyzed by advanced analytical methods. High degree of variation was observed in the concentration of chloride in groundwater, which ranged between 205 and 3310 mg/L, around 56% of the samples were recorded above the acceptable limit indicating the quality of groundwater is fresh to saline and it could be due to mixing of tannery effluents with freshwater aquifers. The chromium in the groundwater around 40% of the sampling wells exceeds the permissible limit whereas, 37% of wells were with fluoride above the accepted limit. Geochemical modelling using Phreeqc suggest that the saturation index of minerals such as calcite, dolomite, fluoride, gypsum and anorthite is affected by precipitation, dissolution and ion exchange processes. Concentration of chromium isotopes δ53Cr and δ52Cr reveals the source of Cr in the groundwater is more likely from tannery effluents. Accumulation of fluoride in groundwater is contributed by bedrock, charnockite, granite, epidote hornblende gneiss, fissile hornblende biotite gneiss in the study area. Groundwater contamination in this area is caused by both natural as well as anthropogenic sources. Around 37% of the samples exceeds HQI limit (HQI>1), which indicates possible health problems to the public upon prolonged use of untreated groundwater for drinking. To overcome this situation, it's essential to improve the performance of the effluent treatment plants and recharge structure to recover the quality of groundwater.

Spatial analysis of groundwater suitability for drinking and irrigation in Lahore, Pakistan.

This study used a total of 474 groundwater samples analyzed from 2014 data to evaluate the distribution of groundwater quality in the Water and Sanitation Agency (WASA) jurisdiction of Lahore city, Pakistan. The study further assessed the variations in suitability of groundwater for drinking (emphasis on arsenic and fluoride) and irrigation using spatial correlation technique in GIS. The hydrochemical analysis revealed a predominance of Mg-Ca-HCO3-SO4 and Ca-Mg-HCO3-SO4 type. Distribution analysis indicated relatively higher salinity (TDSmax = 1667mg/L), total hardness (THmax = 558mg/L), and alkalinity (HCO3-max = 584mg/L) in the south-eastern region of the city, while the central part displayed the highest levels of SO4 and NO3. Also, the eastern region (north-south) of Lahore had significantly elevated As concentrations (up to 86μg/L). The order of exceedance in terms of arsenic was Gunj Bakhsh town (17.4%), Nishter town (16.4%), Iqbal town (9.8%), Aziz Batti and Shalimar town (8.1%), and Ravi town (3%). The groundwater was classified as average saline to highly saline, except few samples in Aziz Batti/Shalimar town that were in non-saline group. Otherwise, the various indices classified the groundwater for irrigation as generally acceptable. With the various irrigation quality indices displaying discernible variations for the entire study area, it was observed from the distribution maps that the groundwater suitability for irrigation is relatively excellent in the areas away from industries and landfill locations. Also, the chloride analysis shows 98.7% of the groundwater samples belong to the very fresh and fresh water class. Thus, continued monitoring and studying the changes in groundwater quality in Lahore is imperative.

Utilization of Anion Exchange Resins: Amberlyst A21 for Sulfate Reduction in Drinking Ground Water and its Characterization

AbstractSulfate (SO4)-2 is ubiquitous in groundwater, with both natural and anthropogenic sources. At high levels, sulfate can give water a bitter or astringent taste and can have mild laxative effectsThe aim of this work is to present experimental results on the evaluation and removal of Sulfate ions from drinking ground water in Wadi El-Assiuti – Egypt using anion exchange resin: Amberlyst A21. The drinking groundwater samples were collected from different places of El-Fath region (Assiut Government) Egypt Amberlyst A21 was characterized by swelling, solubility, thermal properties like: thermal gravimetric analysis (TGA) and differential thermal gravimetric (DTG), X-ray diffraction analysis, and scanning electron microscopy (SEM) were also determined and the data were discussed. Moreover, the present study, anion exchange resins was used to the removal of sulphate (SO4)-2 from ground water used as a drinking water. The effects of different parameters such as different resin dose, pH and contact time were examined. The results show that anion exchange resin (Amberlyst A21) has good affinity towards sulfate (SO4)-2 ion removal that uses especial conditions such as large weight of resin or long time for treatment. And the loading increases with acidity. The Langmuir constants model for (SO4)-2 ions are fitted well on the adsorption isotherms. The RL value in the present investigation was equal or less than one, indicating that the adsorption of (SO4)-2 ion by Amberlyst A21 is favorable.