Seasonal Variation Of Groundwater Quality Research Articles

Seasonal Variation of Groundwater Quality in Bonny Island, Rivers State Nigeria

This study investigated the seasonal variations in physicochemical parameters, heavy metals, and petroleum hydrocarbons in groundwater samples collected in nine locations in Bonny Island, Rivers State Nigeria. The water samples for the dry season were collected in December and January while for the wet season, water samples were collected in July and October. A quantitative approach was employed, involving the collection of quantitative data through field sampling and laboratory analysis. Physicochemical parameters, including pH, electrical conductivity, dissolved oxygen, and nutrient levels, were measured using standard analytical techniques. Heavy metal concentrations (Fe, Cd, etc.) were determined using atomic absorption spectrophotometry, while petroleum hydrocarbons (total hydrocarbons and polycyclic aromatic hydrocarbons) were analyzed through solvent extraction and gas chromatography techniques. The study revealed significant seasonal variations in several parameters, with notable significant decreases in phosphate during the wet season and significant increases in chromium and cadmium levels during the dry season (p-value < 0.05). Petroleum hydrocarbon concentrations also exhibited seasonal fluctuations, potentially influenced by precipitation patterns, oil and gas activities, and accidental spills or leaks which were observed during the dry season.

Seasonal recharge mechanism of the upper shallow groundwater in a long-term wastewater leakage and irrigation region of an alluvial aquifer

Understanding the mechanisms that control seasonal groundwater recharge at local and intermediate scales is critical for understanding contaminant transport. The recharge mechanism of seasonal precipitation and irrigation, companied with legacy wastewater in porewater in alluvial aquifer were complicated due to the seasonal variation of multiple recharge sources. In this study, a long-term wastewater leakage and irrigation region along the Tanghe Wastewater Reservoir (TWR) in the alluvial plain area of North China Plain to investigate the recharge mechanism from unsaturated zone to the upper shallow groundwater affected by multiple water sources. Water chemical ions and stable isotopes of water (2H and 18O) of 30 m deep sediment profiles and groundwater boreholes were used to trace the recharge processes. The porewater stable isotopes of the sediment profiles revealed vertical recharge rates ranging from 0.63 to 1.09 m/year for the layered unsaturated zone with silt and silty clay. Due to the matrix flow through unsaturated zone, the legacy wastewater in the unsaturated zone affected the variation of groundwater quality in long term. However, fast flow (i.e., preferential or lateral flow) occurred in sand layers of alluvial aquifers lead to significant precipitation contributions (44 to 61 %) to the upper shallow groundwater (USGW) recharge, resulting in the seasonal variation of stable isotopes and water chemical ions. Affected by the fast flow with seasonal variations and matrix flow with legacy wastewater in the unsaturated zone, the δ2H and δ18O relationship of the USGW showed two types of hysteresis loops in the dual isotope space: 1) groundwater in regions affected by the TWR wastewater leakage shows narrow loops and a nearly straight line with end-members of precipitation that recharged to groundwater by fast flow, and evaporated porewater plotting along the TWR evaporation line; and 2) groundwater in irrigated farmlands with low and high irrigation amounts and intense evaporation shows stronger hysteresis with loops overlapping with shallow porewater, suggesting the impact of legacy wastewater of the unsaturated zone on groundwater. The residual pollutants in soil and the type of fast flow determine the different seasonal variation of groundwater quality. Preferential flow in alluvial aquifer regions can increase the proportion of seasonal recharge from precipitation, resulting in the rapid introduction of contaminants from surface or shallow soils into the alluvial aquifer.

Effect of seasonal variation in dielectric properties of groundwater from Vadodara region

Groundwater samples were collected during different months from the same site from Vadodara district of Gujarat state. The complex permittivity of the water samples were precisely determined over the frequency span 20 Hz to 2 MHz. Complex permittivity spectral data were converted into complex impedance formalism. Obtained results were analysed to get information of seasonal variation in groundwater quality. Dielectric constant for all samples is found to decrease linearly and rapidly with increase in frequency up to about 4 kHz, after which it decreases slowly and achieves static value approximately 78, near 2 MHz for all water samples. Dielectric loss for the water sample collected in monsoon season (August) is the highest, which shows the presence of ions dissolved from the soil in rain water. DC resistance values, determined from the complex impedance plane plot (Z′’ vs. Z″), suggested an increase in the conductivity of the water samples collected near the end of monsoon season, due to the dissolved minerals and salts from soil. The calculated values of ε′’/ε′’ DW and ε″/ε″DW ratio for the water sample of August’18 show a relatively large increase during the post-monsoon month of August’18, above 2 kHz, as compared to other months.

Seasonal Variations in Groundwater Quality under Different Impacts Using Statistical Approaches

The objective of this study was to evaluate seasonal fluctuations in groundwater quality, determine the effects of different stressors on this resource, and recognize the potential pollution sources in a coastal region of southern Vietnam. Eleven samples collected in Ben Tre province during the dry and wet seasons were then analyzed for sixteen parameters, including pH, total dissolved solids (TDS), salinity, total hardness (TH), ammonium (NH₄⁺-N), nitrite (NO₂ˉ-N), nitrate (NO₃ˉ-N), sulfate (SO₄²ˉ), chloride (Clˉ), iron (Fe), manganese (Mn), lead (Pb), mercury (Hg), arsenic (As), coliforms, and Escherichia coli (E. coli). Pearson correlation analysis, principal component analysis (PCA), and cluster analysis (CA) were employed. The results indicated that total dissolved solids, salinity, total hardness, Clˉ, E. coli and coliform were detected as contaminants in groundwater samples. The trend of fluctuations in the parameters was mostly higher in the dry season. Which Mn and coliform significantly fluctuated between the dry and wet seasons. Activities in industrial-craft areas, landfills and seawater-intruded areas negatively impacted groundwater quality, typically TDS in industrial-craft areas, coliform and E.coliat the landfill area. Six principal components obtained from PCA could explain 93.6% of the variance, and all parameters are responsible for variations in groundwater quality. Geology, discharged wastewater, landfill leachate, agricultural activities, and saltwater intrusion can be considered representative factors. CA grouped the collected samples into four clusters based on the similarity in water properties. The analysis results showed that the locations in each cluster have outstanding water quality characteristics, clusters I and III have high TDS characteristics, cluster II has coliforms, and cluster IV sets of locations with high salinity. This study is promised to partially fill the gap in comprehensive information on groundwater quality in the coastal province so that policymakers can develop sustainable water management strategies in the future. Doi: 10.28991/CEJ-2023-09-03-01 Full Text: PDF

CONCENTRATION LEVELS OF PHYSICO-CHEMICAL PROFILES AND QUALITY ASSESSMENT OF GROUNDWATER: A CASE STUDY OF SOUTHERN IJAW, BAYELSA STATE, SOUTHERN NIGERIA

This study examined the concentration levels of physico-chemical profiles of groundwater quality of communities in Southern Ijaw Local Government Area of Bayelsa State, Nigeria. The seasonal variation of groundwater quality were evaluated. Fifteen (15) communities within the LGA were selected and groundwater from hand-dug well (HDW-15samples) and borehole (BH-15samples) was sourced during the wet season (July) and dry season (March) and analyzed for seasonal variations. The difference in the mean of the parameters investigated during the dry and wet season revealed the difference in concentration level as influenced by the season attributes. The HDW showed a very strong correlation in wet and dry season physicochemical properties as well as no significant difference in the physicochemical properties of groundwater at both seasons. Also, the results of borehole water sample showed a very strong correlation in wet and dry season physic-chemical properties with no significant difference in the physicochemical properties of water at both seasons. There are similarities in various natural and anthropogenic activities influencing the concentrations during both wet and dry seasons. The mean values of parameters such as pH, TDS, TSS, Bicarbonate, Cl, SO34, NO2, Ca, Mg, K and P are within the permissible limit of WHO and NSDWQ during both seasons except TC.

Multivariate Statistical Interpretation and Seasonal Variation of Groundwater Quality for Southwestern Region of NCT Delhi, India

Groundwater (GW) is a major source of drinking water in many parts of the National Capital Region (NCT) Delhi including the southwest part of the city. To assess the GW quality in the study area total 52 GW samples were collected for both pre and post monsoon season for two consecutive years (2019-20) from 13 sampling locations. These samples were then analyzed for 16 physical and chemical water quality parameters including pH, Temperature, EC, Salinity, TDS, alkalinity, TH, NO3-, PO42-, SO42-, F-, Cl-, Ca2+, Mg2+, Na+ and K+. Descriptive analysis and normality check was executed before subjected to multivariate analysis. Pearson correlation explained, positively high correlation coefficient(r) for both pre and post monsoon seasons between TDS and Cl- (r=0.97(pre) and 0.93(post)); salinity and EC(r=0.82(pre) and 0.82(post)); TDS and TH(r=0.86(pre)and 0.83(post)); Na+ and Mg2+ (r=0.80(pre) and 0.81(post)). Factor Analysis depicted TDS, alkalinity, TH, SO42-, F-, Cl-, Ca2+ were significantly loaded components for both the seasons, contributing for 77.84% (pre monsoon) and 82.31% (post monsoon) of component loading respectively. Degradation of water quality is majorly due to growing population and human interventions adding to the diversity of topography and the geology. The interpolation maps generated depict high concentration of alkalinity, salinity, total dissolved solids (TDS), and electrical conductivity (EC) across the study area’.

Seasonal Variation in Groundwater Quality Revealed by the Multi-tracer near the Coastal Area of Sendai, Japan

Seasonal Variation in Groundwater Quality Revealed by the Multi-tracer near the Coastal Area of Sendai, Japan

Evaluation\xa0of\xa0groundwater\xa0quality\xa0and\xa0its\xa0impact\xa0on\xa0human\xa0health: a case\xa0study\xa0from\xa0Chotanagpur\xa0plateau\xa0fringe\xa0region\xa0in\xa0India

Groundwater is a vital and purest form of natural resource. In the recent years, various anthropogenic causes threat its natural quality. Therefore, its suitability for drinking, irrigation and other purposes make doubtful conditions of human well-being, especially in developing countries. In this present study, groundwater quality was evaluated for drinking, irrigation and human health hazard purposes particularly in Chotanagpur plateau fringe of India. In total, 58 water samples were collected from different locations in pre-monsoon (February–March 2020) and post-monsoon (October–November 2020) seasons to delineate seasonal variation of groundwater quality according to as reported by WHO (WHO guidelines for drinking-water quality, World Health Organization, Geneva, 2011) guidelines. Groundwater Quality Index (GWQI) and Heavy metal Pollution Index (HPI) have been applied to assess the suitability of drinking purposes. Irrigation parameters (SAR, SSP, MAR, PI, KR) showed the significant deterioration of water quality in pre-monsoon than post-monsoon period. Major cations (such as sodium, calcium) and major anions (such as bicarbonate, nitrate and fluoride) exceeded their standard limit in both the seasons. Non-carcinogenic health risk is found due to heavy metal contamination through drinking water. The health risk index was higher for children in comparison with adults. This research finding can definitely help to planners and administrators for immediate decision making regarding public health (for groundwater quality improvement).

Statistical assessment of seasonal variation of groundwater quality in Çarşamba coastal plain, Samsun (Turkey).

Çarşamba aquifer is one of the most important coastal aquifers in Turkey. This aquifer is confronted by overexploitation due to the agricultural and industrial activities. The aim of the present study is to investigate the seasonal variations of hydrogeochemical parameters and to assess the suitability for drinking and irrigation of groundwater in the coastal aquifer of Çarşamba plain. For this purpose, in July and December of the year 2019, 33 and 30 groundwater samples respectively were taken from boreholes in the study area and for these samples, EC, pH, TDS, Na+, Ca+, K+, Mg2+, CO3-, HCO3-, Cl-, SO42-, NH4+, NO3-, and NO2- values were determined. Strong correlation was observed between Cl- and Na+ during both seasons indicating the seawater intrusion on groundwater in the study area. Principal component analysis showed that in the study area, seawater intrusion, rock-water interaction, and anthropogenic activities from agricultural areas are the main factors that impact the groundwater chemistry. Seawater intrusion is the most important factor which affects the groundwater chemistry in July while in December, the main factor is rock-water interaction. In December, NO2- and NH4+ values of most water samples exceed the authorized limits of Turkish Standard and WHO. Water quality index indicated that most of the water samples are suitable for drinking. Wilcox diagram and US salinity diagram used to evaluate the suitability of groundwater for irrigation suggested that in July, 87.87% (90% in December) (for Wilcox diagram) and 96.96% (100% in December) (for US salinity diagram) of the water samples belonged to the good to permissible class, and therefore are suitable for irrigation purpose. In addition, the EC, %Na, TH, RSC, SAR, PI, KI, and MH values of samples showed that during both seasons, most of the water samples are suitable for irrigation. However, in July, 51.52% (43.43% in December) of samples have extremely high potential salinity values, thus revealing the unsuitability of most groundwater samples for irrigation in the study area.

Multivariate Analysis of Seasonal Variation in Groundwater Quality within Federal University of Agriculture Abeokuta, Southwestern Nigeria

This research work was aimed at analyzing the data of the seasonal variation of groundwater quality in the Federal University of Agriculture Abeokuta (FUNAAB) environment using descriptive statistics and a covariance matrix analysis of the data set for both rainy and dry seasons to see the effect of the water quality parameters on each other. Cluster analysis was also carried out on the data set to check the level of the Euclidean distance between the water quality parameters. The data used for this analysis was secondary data obtained from groundwater sources (ten wells) within the University environment during the rainy and dry seasons respectively. It was observed that there is a slight variation in the quality of groundwater in the FUNAAB environment as regards the dry season and the rainy season. In the result of the cluster analysis, the water quality parameters are clustered into seven groups for the dry season and eight groups for the rainy season which indicate that the dissimilarities in the data set increase during the rainy season. It was observed that for the dry season covariance data, 36% of the values have a negative relationship within themselves and 64% has a positive relationship, as compared to the rainy season data which possesses a 31% negative relationship and a 69% positive relation. This implies that there is only a 5% variation in the entire data set of the dry season and the raining season as regards the interdependence of the water quality parameters on each other.
 Keywords: Groundwater, Physico-Chemical, Water Quality, Wells

Seasonal Variation in Physicochemical Properties of Groundwater, a Case Study of Kamiti-Marengeta Subcatchment Kiambu, Kenya

The seasonal variation and quality status of groundwater systems of Kamiti-Marengeta sub-catchment were evaluated through analysis of boreholes and 17 shallow wells water samples in May 2016 and September 2017. Consequently, the results were compared against the Kenya Bureau of Standards (KEBS) and World Health Organization (WHO) guidelines for drinking water purposes, and its suitability for drinking was established. The results showed that turbidity, calcium, potassium, iron, and fluoride levels in some of the boreholes and pH, calcium, sodium, and iron levels in some shallow wells exceeded the KEBS and WHO standards for drinking water quality. Turbidity, dissolved oxygen, and total hardness significantly varied across the regions of the study, and one-way ANOVA (P < 0.05) indicated a significant difference in the mean concentration of electrical conductivity, turbidity, total hardness, calcium, and iron in boreholes and in all parameters in shallow wells except for magnesium during the two seasons. The findings of this study provide baseline information on the quality of the groundwater systems of the area. It also contributes to knowledge on seasonal variation of groundwater quality of volcanic aquifers like the Nairobi Aquifer System (NAS) which is important for water quality monitoring.

GROUNDWATER POLLUTION STUDIES IN CHIKHALTHANA MIDC AREA, AURANGABAD DISTRICT

The water shortage is amongst the most critical concerns of this century. Groundwater quality is being severely harmed by the industries’ rapid expansion and the careless dumping of their industrial waste water nearby. One of the main cities in the Deccan sub-region is Aurangabad, which is situated in the heartland of Maharashtra State, India, which is prone to drought. In order to determine how seasonal variations in groundwater quality affect irrigation and human health, the Chikalthana neighborhood of Aurangabad was chosen. Using the analytical methods. There has been an effort to investigate the state of the water in the current study. Groundwater around Chikhalthana industrial areas underwent physicochemical investigation. In the summer and winter seasons, 5 locations provided the samples of groundwater, that were analyzed for temperature, pH, electrical conductivity, total hardness, total dissolved solids, turbidity, alkalinity, DO, BOD, COD, chloride, ammonia, calcium, magnesium, iron and nitrate. According to the findings of the physicochemical analysis of 16 water quality indicators, the pH, electrical conductivity, total hardness, chloride, ammonia, calcium, magnesium, iron, and nitrates were all within acceptable limits. While the turbidity, dissolved oxygen, and biochemical demand of the groundwater were higher than allowed in both time periods.

Seasonal Variations in Groundwater Quality and Hydrogeochemistry in the Endemic Areas of Chronic Kidney Disease of Unknown Etiology (CKDu) in Sri Lanka

Groundwater quality and geochemical processes were investigated in the endemic areas of chronic kidney disease of unknown etiology (CKDu) in Sri Lanka. Representative groundwater samples (n = 60) were collected from 30 dug wells located in the Anuradhapura district, over the dry and wet seasons. The samples were analyzed for pH, electrical conductivity (EC), total dissolved solids (TDS), alkalinity, major cations and major anions. Calcium-magnesium-bicarbonate ion combinations are predominant in this groundwater, and the simultaneous occurrence of high hardness (382–394 mg/L as CaCO3), alkalinity (364–379 mg/L as CaCO3) and ionicity is a salient characteristic. Alkalinity, TDS, hardness, and magnesium exceeded the safe limits for drinking in over half of the samples, regardless of the season. The major ion chemistry (Ca2+, Mg2+, Na+ and HCO3−) is primarily governed by the weathering of carbonate and silicate minerals, ion exchange, and evaporation which is accelerated by the semi-arid climate. Fluoride and chloride inputs are regulated by dissolution of fluoride-bearing minerals and anthropogenic causes, respectively. Saturation indices suggested supersaturation of carbonates and silicates, and undersaturation of evaporites and fluorite. Persistent high ionicity, and hardness of groundwater that is seldom impacted by seasonal variations might be playing a vital role in the genesis of CKDu.

Seasonal Variation of Groundwater Quality for Irrigational uses in Gadilam River Basin, Tamil Nadu, India

The present research work pertains to the Gadilam river basin groundwater quality for irrigation uses with respect to the Archaean formation, the Quaternary formation, the Tertiary formation and the Cretaceous formation. Experiments were carried out for two seasons (rainy season and summer season) for two successive years (November 2018 and June 2019). Overall, 120 groundwater samples were collected from the Gadilam river basin, excluding the reserved forest area. The 50 samples were collected from the Archaean formation, 34 samples from the Quaternary formation, and 35 samples from the Tertiary Formation. The remaining sample is from the Cretaceous formation. Based on the obtained analysed data, the following agricultural water quality parameters were calculated using the following expressions: The irrigational quality parameters are used, such as sodium percentage (Na%), sodium adsorption ratio (SAR), Kelly’s ratio (KR), permeability index (PI), magnesium ratio (MR), residual sodium carbonate (RSC), and potential salinity (PS) are calculated and assessed for irrigation purposes.

Integrated approach for the evaluation of groundwater quality through hydro geochemistry and human health risk from Shivganga river basin, Pune, Maharashtra, India.

The present study is focused on seasonal variation in groundwater quality, hydrochemistry, and associated human health risk in the Shivganga river basin, Western Maharashtra, India, to promote sustainable development of groundwater resources of this semi-arid region. The qualitative geochemical analysis, contamination levels, and human health risk assessment (HHRA) of groundwater are integral steps in groundwater management in the Deccan Plateau basalt flow region of India. Representative groundwater samples (n = 68) collected from the Shivganga River basin area of Pune district, Maharashtra, during pre-monsoon (PRM) and post-monsoon (POM) seasons in 2015 were analyzed for major cations and anions. According to the World Health Organization (WHO, 2017) drinking standards, EC, total dissolved solids, hardness, bicarbonate, calcium, and magnesium surpassed the desirable limit. Boron and fluoride content exceeded the prescribed desirable limit of the WHO. The pollution and drinking suitability were assessed by computing pollution index of groundwater (PIG), groundwater quality index (GWQI), and HHRA particularly for boron and fluoride toxicity. PIG values inferred that about 6% of groundwater samples has moderate, 24% has low, and 70% has insignificant pollution in the PRM season, while only 1 sample (3%) showed high pollution, 6% showed low, and 91% showed insignificant pollution in the POM season. GWQI classification demonstrated that 27% and 15% samples are within the poor category, and only 15% and 18% of the samples fall into excellent water category in the PRM and the POM seasons, respectively. Total hazard index (THI) revealed that 88% of children, 59% of adults, and about 38% of infants are exposed to non-carcinogenic risk, as THI values (>1) were noted for the PRM season, while 62% of children, 47% of adults, and 24% of infants are vulnerable to non-carcinogenic health hazard during the POM period.

Seasonal variation in groundwater quality and beneficial use for drinking, irrigation, and industrial purposes from Deccan Basaltic Region, Western India.

Sustainable management of groundwater resources requires detailed basin-wide water assessments. Semi-urbanized areas surrounding metropolitan cities in the western part of India were assessed for their suitability for domestic, irrigation, and industrial purposes. These study areas reflect rapid urban growth with residential complexes, combined with agricultural, horticultural, and industrial uses. Therefore, 68 representative groundwater samples were collected during the pre-monsoon (PRM) and post-monsoon (POM) seasons of 2015 and analyzed for major ions. According to the World Health Organization (WHO) drinking standards, parameters like EC, TDS, TH, HCO3, Ca, and Mg were found to exceed the desirable maximum limits, and the B and F content exceeded the permissible limits. The drinking suitability was studied using the modified water quality index (MWQI). The irrigation suitability was assessed using indices such as sodium adsorption ratio (SAR), percent sodium (%Na), and permeability index (PI). The industrial suitability was evaluated based on Langelier saturation index (LSI), saturation index (SI), Ryznar stability index (RSI), etc. MWQI results corroborate that 52.94 and 70% samples fall in no pollution category, and 47% and 30% samples were identified to be in the moderate category of pollution in the PRM season and POM season, respectively. The spatial variation maps of LSI, SI, RSI, Puckorius scaling index (PSI) and Larson-Skold index (LaI) show that the majority of the samples in the PRM season have low to insignificant scaling and corrosive potentials as compared to POM samples. The study results provide reliable information for water reserve managers to prepare the sustainable and more accurate basin management plans.

Study on Seasonal Variations and Spatial Distribution of Major Ions with Focus on Paper Industry Effluents - A Case study of Sirpur Paper Mills (SPM) Telangana

The present paper examines the seasonal variations in groundwater quality (Pre-monsoon &amp; Post- Monsoon) with an emphasis on paper industry effluents from the Sirpur-Kaghaznagar area. Spatial distribution of samples from 24 sites collected during pre and post-monsoon using surfer software gives an insight of important parameters such as pH, EC, TDS, BOD, COD, DO, Ca+, Mg2+, Na+, F, Cl-, NO3,- SO42- and TH to be significantly elevated beyond the acceptable and permissible levels prescribed by BIS limits. Also, the Physico-chemical analysis of paper mill effluent collected from 12 different sites revealed that parameters such as pH, EC, TDS, BOD, COD, Alkalinity, SO42-, Cu, and Fe were beyond the BIS permissible limits for effluent discharge and designated a profound negative impact on groundwater quality and lead us to conclude that the overall quality is deteriorated due to the influx of paper industry effluents.

Seasonal Variation of Groundwater Quality for Irrigational Uses in Gadilam River Basin, Tamil Nadu, India

Seasonal Variation of Groundwater Quality for Irrigational Uses in Gadilam River Basin, Tamil Nadu, India

Multivariate statistical interpretation on seasonal variations of fluoride-contaminated groundwater quality of Lalganj Tehsil, Raebareli District (UP), India

Quality of groundwater is concerned with various processes such as precipitation, weathering and dissolution of mineral, cation exchange and ground water exploitation. Present study aims to interpret the seasonal variation of groundwater quality contaminated with fluoride. Sixty water samples were collected during pre- and post-monsoon seasons from Lalganj Tehsil of Raebareli District, UP (India). Multivariate statistical analyses such as factor analysis (FA), principal component analysis (PCA), cluster analysis and correlation matrix were applied on 14 hydro-chemical constituents, i.e., pH, EC, TDS, TBDT, TH, bicarbonate (BiC), NO3−, SO42−, F−, Cl−, Ca2+, Mg2+, Na+ and K+. Factor analysis explained that TH, Mg2+, SO42−, Cl−, EC, TDS and F− were significantly loaded parameters during both seasons that influence the groundwater quality due to weathering and dissolution of mineral during aquifer recharging. The source of F− appears to be geogenic due to the alluvial sediments deposited in the geological past as no hard rock terrain was present in the nearby areas that were dominantly made up of mud with pocket of sand. The cumulative variance obtained from PCA suggested that the groundwater quality in pre-monsoon was better than that of post-monsoon. Correlation explained that EC of groundwater completely depends on the dissolved solids. Dendrogram of cluster analysis indicated that parameters were grouped into four clusters on the basis of similarity, during both seasons. Values of Mg+, F−, TH, and TDS exceeded more than the drinking water standard during both seasons. It will bring alertness to the people regarding whether the groundwater is suitable or unsuitable for drinking purpose.

Appraisal of seasonal variation of groundwater quality near an uncontrolled municipal solid waste landfill in Kolkata, India

The present study was aimed to evaluate the impact of leachate derived from uncontrolled municipal landfill on surrounding groundwater quality in Kolkata, India. Seasonal variation of twenty physico-chemical parameters in pre-monsoon (PRM) and post-monsoon (POM) season were analysed in forty groundwater samples around the landfill site. Groundwater pollution was identified by the spatial distribution maps of TDS, Na⁺, Cl⁻, Mn and Fe along with the heavy metals like Pb, Hg andCr in both the seasons. Hydrogeochemical characteristics of groundwater samples showed that the area was dominated by brackish water, [Ca⁺2−Cl⁻], [Mg⁺2−Cl⁻] and [Na⁺−Cl⁻] type in PRM season whereas [Na⁺−HCO3⁻] type dominated in POM season. Hierarchical cluster analysis (HCA) was also applied to identify the source of groundwater pollution. In PRM season, groundwater samples closer to the active landfill site were physico-chemically different from upstream samples but more related to downstream samples. However, in POM season, groundwater samples closer to the active landfill site represented distinctly different physico-chemical characteristics from upstream and downstream samples as a result of high influx of leachate pollutants. In specific, the present study urges for proper pollution control measures along with landfill leachate treatment process to improve the surrounding water quality.