Papers by Keyword: Groundwater

Abstract: The increasing demand for clean water necessitates the development of advanced and cost-effective treatment technologies. Nanofiltration (NF) membranes offer high efficiency in removing divalent ions, but their application is often limited by membrane fouling and stability issues. While various polymer blends have been studied to address these limitations, the effect of incorporating chitosan (CS) into polyethylene glycol/cellulose acetate (PEG/CA) membranes for treating calcium-rich water remains underexplored. This study aimed to evaluate the impact of CS incorporation on the performance of PEG/CA NF membranes, specifically focusing on water flux and salt rejection in the removal of calcium carbonate from simulated groundwater. Membranes with 1–3 wt % CS were fabricated and compared to unmodified PEG/CA membranes. Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) spectroscopy confirmed CS presence, while Scanning Electron Microscopy (SEM) revealed morphological changes. Performance testing showed that the 1 % CS membrane had the highest water flux, whereas the 3 % CS membrane achieved the highest salt rejection. An inverse relationship between flux and rejection was observed with increasing CS content. Statistical analysis confirmed significant performance differences between modified and unmodified membranes. These results indicate that chitosan incorporation enhances NF membrane performance, offering a promising approach for improving water purification systems, particularly for hard water treatment.

Abstract: The findings from this study proved the possible usefulness of shredded recycled rubbers from scrap tires as a cheap and effective method for eliminating nitrate ions from water, especially within a certain pH range. Maximum adsorption efficiency was found to occur around pH = 6 which suggested that the surface charge on the adsorbent and the concentration of ions in the medium observed were critical for adsorption. Under controlled conditions and a pH of 6 with an original concentration of 100 mg/L, the adsorption efficiencies of NaNO₃ and KNO₃ were 67% and 60% respectively. These increased to 77% and 70% at 200 mg/L, pH 6. These results elucidate that the type of cation and the chemistry of the solution influences the adsorption process. The kind of nitrate salt employed also had an impact on removal efficiency, with potassium nitrate performing better than sodium nitrate, highlighting the relevance of the associated cation type in the process. As a result, the utilization of recycled rubber might be regarded as an environmentally viable solution for treating nitrate-contaminated water, especially in decentralized treatment systems and mild pH conditions. In addition, shredded tire rubber provides an effective, low-cost, and sustainable solution for nitrate-contaminated groundwater treatment.

Abstract: This study addresses the increasing occurrence of sinkholes in northern and eastern Saudi Arabia, driven by soluble karst geology and unsustainable groundwater extraction. The primary objective is to understand the underlying mechanism of sinkhole formation and propose targeted mitigation strategies. By integrating geological, geophysical (ERT, GPR, microgravity), and hydrological data from previous studies, the research identifies key subsurface features and groundwater conditions contributing to sinkhole development. The results reveal that sinkhole formation is primarily governed by cover-collapse processes, strongly associated with aquifer over-extraction, low-resistivity anomalies, and irrigation-induced saturation. Groundwater declines of 2.5–3 m/year, along with acidic and saline conditions, further accelerate karst dissolution. The study concludes with a three-part mitigation framework: sustainable groundwater management, engineered stabilization of high-risk cavities, and an integrated early-warning system using geophysical monitoring and InSAR. These findings offer a practical roadmap for managing sinkhole hazards in arid karst environments.

Abstract: Source fondamentale d'eau potable et d'irrigation agricole, les eaux souterraines sont indispensables, notamment dans les régions où les eaux de surface restent rares. L'aquifère du Saïss, situé dans le bassin du Sebou au nord du Maroc, joue un rôle crucial dans le maintien des communautés locales et des activités économiques. Cependant, les pressions anthropiques croissantes et les conditions environnementales changeantes menacent sa qualité et sa disponibilité. Cette étude examine l'impact des activités humaines, des conditions géochimiques et des fluctuations saisonnières sur la composition des eaux souterraines. Des analyses physico-chimiques approfondies ont été menées sur des échantillons d'eau prélevés sur plusieurs saisons afin d'évaluer les concentrations d'éléments indicateurs de qualité tels que les nitrates, les sulfates, les chlorures et les ammoniums. Des approches statistiques descriptives ont été utilisées pour l'analyse des données, complétées par une analyse en composantes principales (ACP) afin de déterminer les relations entre les caractéristiques et de différencier les effets des causes géologiques et anthropiques. Les résultats indiquent une baisse significative de la qualité des eaux souterraines, principalement due aux pratiques agricoles intensives, à l'infiltration d'engrais et de pesticides, et aux effluents d'origine domestique et industrielle. En saison sèche, la pollution est plus marquée, caractérisée par des concentrations élevées de chlorures (850 mg/L), de sulfates (440 mg/L) et de sodium (320 mg/L). À l'inverse, pendant la saison des pluies, l'infiltration due aux précipitations intensifie la contamination, notamment en raison des niveaux élevés de nitrate et d'ammonium. Les résultats soulignent la vulnérabilité de l'aquifère du Saïss aux pressions anthropiques et aux fluctuations climatiques, soulignant la nécessité immédiate de stratégies de gestion durable pour réduire les risques de contamination et garantir la préservation à long terme de cette ressource en eau essentielle pour les besoins, tant pour l'eau potable que pour l'agriculture.

Abstract: The chemical characterization of the Ghis-Nekor aquifer has attracted significant attention from researchers in Morocco. It is a crucial indicator of the environmental situation and the socio-economic development of this Moroccan region. Indeed, it helps decision makers to conduct a conscious and sustainable management. The primary objective of this study is to investigate the origin of salinity using isopoly elements such as Stronstium and Bromide and to evaluate the physicochemical quality of groundwater in the Ghis-Nekor aquifer region and to determine the sources of pollution in order to establish maps of the qualities of the Ghis-Nekor water table. For this reason, of Ghis-Nekor aquifer 19 samples were examined during the month of July 2023, in terms of isotopic elements such as bromine (Br) and strontium (Sr) et tantalum (Ta) (03 samples), and in terms of physico-chemical parameters such as pH, temperature, electrical conductivity (EC), Chlorides, Nitrates, Ammonium, Nitrite, Sulfates, Sodium, Potassium, Bicarbonates, Calcium, orthophosphates and Magnesium . The spatial distribution of the results was visualized through thematic maps generated using a Geographic Information System (GIS), offering crucial insights for decision-making processes related to water resource management in the region.The water temperature varies between 15.1 and 49°C. The pH is close to neutral, varying between 6.65 and 7.86. The waters are classified into three distinct chemical facies: chlorinated and sulfated calcic-magnesium facies, bicarbonated calcic-magnesium facies, and chlorinated sodium-potassium facies.The degradation of water quality in the aquifer of the basin of Ghis-Nkour could have geological and anthropogenic origins. The analysis of bromide and strontium contents allows to discriminate the origin of salinity anomalies. Molar ratios such as Cl/Br, Br/Cl, and Sr/Ca are employed to distinguish areas influenced by geological factors, such as the leaching of salt formations and facies, from those impacted by anthropogenic activities.

Abstract: The paper explores the problem of optimizing groundwater sampling in areas affected by multiple rocket launcher systems (MRLS). Taking into account modern challenges to the safety of the population and the environment in the conditions of hostilities, an express method of preliminary zoning of groundwater pollution based on the measurement of electrical conductivity has been proposed. The method is based on modeling the spread of contaminants in combination with cluster analysis of these measurements. The results of the study can be used for operational monitoring of territories affected by hostilities and in management decision-making systems in the field of civil protection.

Abstract: About a third of the world's population relies on groundwater for their water supply. However, in some cases, the quality of these sources is not suitable for human consumption. Reverse osmosis (RO) membrane technology is used in many cases to improve groundwater quality. Often, for effective performance of RO membranes pre-treatment of source water is required. This study aimed to assess the performance of the pre-treatment components of the brackish water RO desalination plants at the Grünau and Bethanie water supply areas. To assess the performance of the pre-treatment components at these two water supply areas, samples for water quality analyses like turbidity, fluoride, nitrate, and hardness were collected from the raw water and pre-treated water. The average removal efficiency of Bethanie’s sand filters was -2.14% for turbidity, hardness, nitrate, and fluoride. Sand filtration is a technology employed to reduce suspended solids (i.e. turbidity) and can improve microbiological quality. Sand filtration can also be used to remove precipitates formed after an oxidant was applied for example removal of iron and manganese. The negative value indicates that the sand filters were not effective in removing these contaminants, and in fact, they increased in concentration. The raw water was classified as group C, and the pre-treated water after sand filtration was group C as well. The average removal efficiency of Grünau’s sand filters was -43.28% for turbidity, hardness, nitrate, and fluoride. Again, this negative value indicates that the sand filters were not effective in removing these contaminants, and in fact, increased the concentrations. The raw water quality was classified as group D which remained as group D after sand filtration. The raw sources of water at both the treatment plants are groundwater abstracted from boreholes. This study demonstrated that the sand filters used in the pre-treatment at both plants provided minimal to no improvement in raw water quality and increased water losses through backwashing. Suspended solids and microbiological quality often do not require treatment with the use of groundwater, and therefore application of sand filtration technology as pre-treatment component not clearly justified. Therefore, future considerations regarding the use of these pre-treatment components in relation to raw water quality dynamics should be taken into account.

Abstract: The Dumoga area, which includes the districts of Dumoga, West Dumoga, East Dumoga, Central Dumoga, South-east Dumoga, and North Dumoga in Bolaang Mongondow Regency, North Sulawesi Province, is an agricultural area that relies on groundwater for agricultural irrigation. To ensure the sustainability of the groundwater resources, it is crucial to protect the recharge areas. This study aimed to determine the locations of groundwater recharge areas in the Dumoga region using stable isotopes, specifically oxygen-18 (18O) and deuterium (D). Measurements of groundwater levels (GWL) were conducted to understand the direction and flow of groundwater, while measurements of electrical conductivity (EC) and groundwater temperature served as supporting parameters to assess the groundwater conditions in the research area. The findings revealed that the groundwater in the Dumoga region originates from the surrounding hills, with estimated recharge areas in surronding hills ranging in elevation from 326 meters above sea level (masl) to 462 masl.

Abstract: The Northern Slope of Lawu Volcano has great groundwater potential and is widely used for agricultural irrigation. During the dry season, rainfed agricultural land relies on groundwater extracted from deep wells to fulfil its irrigation water requirements. However, this practice has led to a decline in the groundwater table in the shallow wells used by the local community. Effective groundwater management is essential to strike a balance between groundwater extraction and recharge. The objective of this study is to identify groundwater recharge areas on the Northern Slope of Lawu Volcano. The research methodology involves collecting samples of rainwater and groundwater for the analysis of stable isotopes, specifically Oxygen-18 and Deuterium. These stable isotope values are employed to determine the source of the groundwater. Rainwater samples were taken at seven different elevations, with a range between 54 and 1,052 meters above sea level (masl), to form the Local Meteoric Water Line (LMWL). In addition, groundwater samples were taken to determine groundwater sources, consisting of four samples of spring water, two samples of dug wells, and four samples of deep wells. The results of this study are expected to reveal that the water recharge area originates from an altitude of around 1,500 to 2,900 masl. These findings serve as an initial step in identifying the location of the groundwater protection zone for converse the sustainability of groundwater resources on the Northern Slope of Lawu Volcano.

Abstract: The rich karstic limestone aquifer in Kinta Valley, Perak is a potential resource of clean water in the future when the surface water resources will deplete and insufficient to support the growing population. A proper preliminary evaluation of groundwater hydrogeochemistry is essential for knowing the proper application and maintaining the available groundwater as a sustainable resource. Four production wells in Kinta Valley are sampled and analyzed for physicochemical parameters from 2018 to 2020. In this study, major chemical compounds, pH, total hardness (TH), and total dissolved solids (TDS) are interpreted to construct Piper’s trilinear diagram and Gibbs plot which describe the hydrochemistry of the samples. Drinking Water Quality Standard from the Ministry of Health Malaysia (MOH) and the United States Environmental Protection Agency (US EPA) National Primary Drinking Water Regulation is used as guideline standards for water quality evaluation. Based on the results from this study, the quality of groundwater in Kinta Valley is healthy and has the potential to be used as drinking water besides using as irrigation water. The predominant hydrochemical reaction of the groundwater is found to be a bicarbonate-calcium-magnesium reaction, which shows the aquifers are in contact with the subsurface karst system as the main ions originated from the dissolution of carbonate bedrocks.