Geo-Temporal Signatures of Physicochemical and Heavy Metals Pollution in Groundwater of Khulais Region—Makkah Province, Saudi Arabia

Seawater has intruded into many of Saudi Arabia’s Red Sea coastal aquifers, with varying degrees of extension depending on location, hydrogeology, and population density. This study aimed to evaluate and comprehend the processes that influence the hydrogeochemical characteristics of the coastal aquifer in Saudi Arabia’s Khulais region. Groundwater samples were taken from nineteen locations during the winter and summer of 2021, and data from major ions and trace elements were examined and interpreted using ArcGIS software. The total dissolved solids (TDS) concentrations ranged between 480 and 15,236 mg/L and 887–18,620 mg/L in winter and summer, respectively. Groundwater TDS concentration was observed to be influenced by groundwater flow, lithogenic, anthropogenic, and seawater intrusion in this study (2021) when compared to 2016. The concentration of nitrate (NO3−) and strontium (Sr) in most samples exceeds the drinking guidelines. The occurrence of high concentrations of bromide (Br), Fluoride (F), Iron (Fe) (winter and summer) and Aluminum (Al), Boron (B), Chromium (Cr), Nickel (Ni), lead (Pb), cadmium (Cd), cobalt (Co), copper (Cu) and manganese (Mn) (winter) was also exhibited and observed up to more than drinking and irrigation limits. The central part of the study area was affected by seawater intrusion. The hydraulic conductivity of the topsoil was measured, and it ranged from 0.24 to 29.3 m/day. Based on electrical conductivity (EC) and sodium absorption ratio, most aquifer samples were unsuitable for irrigation (SAR).

Physicochemical Parameters and Suitability for Irrigation of Groundwater Resources from Biskra Area (Southeastern Algeria)

This study is part of the more general framework for diagnosis of the quality of water resources in the Biskra area and its suitability for irrigation. This work reports the results of an analysis of physicochemical groundwater quality. Groundwater samples were collected from 12 boreholes in different aquifers exploited in the area, and used for drinking and domestic purposes. The results showed that the water of the limestone aquifer (Maastrichtian) is better than other aquifers (phreatic, Miopliocene, Lower Eocene). This affects more particularly the pH, conductivity (mineralization), total hardness, and concentration of the major elements. As far as the same aquifers (phreatic, Miopliocene, Lower Eocene), present water which classified mediocre highly mineralized for irrigation because EC > 2250 μS/cm (class 4). The Maastrichtian aquifer presents a poor water quality (class 3), according to the Riverside classification.

Concentration Mechanism of Fluorine, Arsenic, and Uranium in Groundwater of the Hailar Basin, China

Located in semi-arid regions of Hulun Buir League in China Inner Mongolia Autonomous Region, Hailar Basin is a region with less precipitation, where groundwater is the most important source for water supply. It is very important to study groundwater characteristics and hydrogeochemical processes for better management of the groundwater resource.The current status of fluorine (F), arsenic (As), and uranium (U) co-contamination exists in groundwater of the Hailar Basin, China. To understand the concentration mechanism of F, As, and U in groundwater in the study area, groundwater samples were collected for detection and analysis. The results showed that the main hydrochemical types were Cl-Na, HCO3-Na, and HCO3-Ca in the study area. The average values of F, As, and U were 3.94 mg/L, 0.04 mg/L, and 0.07 mg/L, respectively, which all exceeded the World Health Organization(WHO) guidelines. Through the Gibbs diagram and the end member diagram, it can be seen that the groundwater in the study area is mainly affected by the hydrogeochemical effects of evaporative crystallization, rock weathering mechanism, and the dissolution of silicate rock and evaporative salt rock minerals. Mineral dissolution, cation exchange, and weakly alkaline environment are important factors affecting F concentration; Low NO3ˉ and SO42- will cause a reducing environment and the competitive adsorption of HCO3ˉ will promote As pollution; The concentration of Ca2+,Mg2+, SO42-,and NO3ˉ have a great influence on the concentration of U.

Hydrogeochemistry of porphyry related solutes in ground and surface waters; an example from the Casino Cu-Au-Mo deposit, Yukon, Canada

The Casino Cu-Au-Mo deposit is one of the largest and highest-grade porphyries of its kind in Canada, residing in an unglaciated region of west central Yukon. A batch of 22 stream water samples and eight groundwater samples were collected proximal to the deposit for the purpose of identifying the most diagnostic trace element and isotopic pathfinders associated with the hydrothermal mineralization, as well as establishing natural hydrogeochemical baselines for the area. Water chemistry around this deposit was investigated because: (i) the deposit has not yet been disturbed by mining; (ii) the deposit was known to have metal-rich waters in local streams; and (iii) the deposit has atypically preserved ore zones. Surface and ground waters around the Casino deposit are anomalous with respect to Cd (up to 5.4 µg/L), Co (up to 64 µg/L), Cu (up to 1657 µg/L), Mo (up to 25 µg/L), As (up to 17 µg/L), Re (up to 0.7 µg/L), and Zn (up to 354 µg/L) concentrations. Sulfur and Sr isotopes are consistent with proximal waters interacting with the Casino rocks and mineralization; a sulfide-rich bedrock sample from the deposit has δ34S = -1.2 ‰ and proximal groundwaters are only slightly heavier (-0.3 to 3.1 ‰). These geochemical and isotopic results indicate interaction and dispersion of porphyry related solutes in ground and surface waters and point to suitability of hydrogeochemistry as a medium for mineral exploration for porphyry-style mineralization in the Yukon, and elsewhere in Canada.Supplementary material: The physicochemical, major, trace, and isotopic data of stream and groundwaters used in this manuscript is publicly available as an Open File Report (OF 8823) from the Geological Survey of Canada.Thematic collection: This article is part of the Hydrochemistry related to exploration and environmental issues collection available at: https://www.lyellcollection.org/cc/hydrochemistry-related-to-exploration-and-environmental-issues

Isotopic Assessment of Groundwater Salinity: A Case Study of the Southwest (SW) Region of Punjab, India

In recent decades, due to rapid increases in water demand and greater usage of water for irrigation from surface canals, waterlogging problems have been created in the southwest zone of Punjab, coupled with a stagnation in saline zone formation due to salinity ingression. To understand these salinity issues, the present study has been conducted in three districts (Muktsar, Fazilka, and Faridkot) of Punjab to understand the root cause. To this end, groundwater samples were collected from 142 piezometers developed at 40 sites. Electrical conductivity (EC) observations were taken in the field, and collected samples were analyzed for isotopes in the laboratory. Results found that salinity in groundwater arises from the combination of evaporation enrichment and salt dissolution. The dissolved salts may be acquired due to salts from aquifer materials or salts from surface soils dissolving and leaching down with the recharging water. Besides, the zone of interaction is mapped using stable isotopic composition. The study suggests that zone of interaction between aquifers can be effectively used in groundwater augmentation, management, and contamination control at regional and/or global scales to curb water demand in the future.

Groundwater quality mapping for drinking and irrigation purposes using statistical, hydrochemical facies, and water quality indices in Tercha District, Dawuro Zone, Southern Ethiopia

When groundwater quality is good, it may be a substantial water supply for various applications. However, no systematic research on hydrogeochemistry and water quality features for drinking and irrigation has been undertaken in the present study area. As a result, the current study looked at hydrogeochemical variables and groundwater quality for drinking and irrigation in Tercha district, Dawuro Zone, Southern Ethiopia. Forty-seven groundwater samples were collected and tested to satisfy the required target for various physicochemical properties. The hydrogeochemical features of the groundwater in the study region were assessed using in-situ testing and laboratory analysis of physicochemical parameters. Groundwater samples from the research region were slightly acidic to slightly basic, with the principal cations and anions decreasing in sequence: Na+ > Ca2+ > Mg2+ > K+ and HCO3-> Cl-> SO42-. The hadrochemical facies of the studied region evolved from mildly mineralized dominant highland Ca-HCO3 water types to moderately mineralized mixed Ca-Na-HCO3 water types to highly mineralized deep rift floor Na-HCO3 water types. Additionally, the World Health Organization and the Ethiopian Standard Agency were utilized to compare the drinking water quality. Except for NO3- (4.25 %), Fe (8.51 %), and F- (2.12%), all groundwater samples from the research region were determined to be within permitted limits and appropriate for drinking. According to the Water Quality Index, about 80.86% of groundwater samples are excellent, and 19.14% are good drinking water. Sodium absorption ratio (SAR), sodium (Na) percentage, residual sodium carbonate RSC, permeability index (PI), and magnesium hazard were among the irrigation water quality indicators calculated (MH). The great majority of groundwater samples are suitable for agricultural use.

Health risk assessment of arsenic in drinking groundwater: A case study in a central high land area of Vietnam

Arsenic contaminated groundwaters is a global environmental issue which cause serious problems for human health risks. 188 groundwater samples were collected in private wells of Lam Dong Province, a central highland area, Vietnam to investigate the health risks to the local people by using arsenic contaminated groundwater for drinking purpose. The result showed that the arsenic concentration is average of 14 μg/L and maximum of 500 μg/L. About 12% out of the total groundwater samples have arsenic concentration exceeded that value of 10 μg/L recommended for drinking water by World Health Organization (WHO, 2019). The health risk assessment showed that hazard quotient (HQ) value for adults was up to 60.6 with an average of 1.7 and about 14% of total samples show the HQ values greater than 1. The HQ value for children is average of 4.7 (maximum of 166.7) and about 23% of total groundwater samples show HQ > 1 for children. Cancer risk (CR) values were up to 27x10-4 (average of 8x10-4) for adults and 75x10-4 (average of 21x10-4) for children. About 26% and 29% of out of the total samples show CR value for adult and children greater than the CR (1×10-4) proposed by the USEPA. The result also indicated that the consumption of arsenic contaminated groundwater may seriously damage the human health. Therefore, groundwater in the area needs to be treated for arsenic removal before drinking to minimize the adverse effect on local communities’ health.

A systematic study of uranium in groundwater and its correlation with other water quality parameters

A parametric investigation was carried out to estimate the Uranium concentration and other associated water quality parameters for the groundwater in Deoghar district, Jharkhand. Total 150 groundwater samples have been collected from dig wells, hand pumps, tube wells, etc. for the pre and post-monsoon seasons. A Quantalase Uranium analyzer was used to measure the uranium concentration. The distribution of pH, TDS, DO, nitrate, sulfate, uranium along with the radiation has been determined. It was found that the uranium concentration in groundwater varies from 0.10 to 11.30ppb in pre-monsoon and 0.15–6.50ppb in the post-monsoon which is well below the normal tolerance limit (i.e.30 μg/l WHO). This low availability of Uranium has been attributed due to the existence of a lesser number of rocks containing uranium as a source in that area. An attempt has been made to correlate the uranium concentration with the water quality parameters for both seasons. The correlation data reveals that ORP, nitrate, phosphate, calcium, and magnesium show a positive correlation with uranium concentration for both seasons on the other hand TDS, EC, temperature, DO, fluoride, and chloride show negative correlation. The positive correlation implies that uranium may be present in groundwater as a dissolved salt of these parameters. Comparative studies for the parameters have been done for both the seasons and various factors have been discussed for the occurrence of the same. The annual effective dose associated with the ingestion of uranium by the population of the region has been estimated using USPEA equations.

Resilience to climate change: adaptation strategies for the water supply system of Formia and Gaeta (Province of Latina, Central Italy)

The aqueduct serving the municipalities of Formia and Gaeta (Latina province, Italy), an area under the enforcement and control responsibility of “ATO 4” Autorità d’Ambito Territoriale Ottimale – (Integrated Urban Water Management Agency), is supplied by two important karst springs. These springs, fed by the western Aurunci Mountains system are known as Mazzoccolo and Capodacqua having an average flow rates of 1100 l/s and 1300 l/s, respectively. Although these sources have been used since ancient Roman times and the quality of their water is excellent, variations in the precipitation regime, possibly related to worldwide climate changes, has exacerbated the following problems: a decrease in the flow rates of the springs caused by the reduction in winter rainfall, and an increase of turbidity due to concentrated rainfall events. In order to mitigate these problems, which affect a resident population of about 150,000 inhabitants, Acqualatina S.p.A. - the water utility company - promoted a series of geological and hydrogeological surveys. These studies aim at increasing the knowledge on the geological setting and to find additional sources to improve the existing supply. Within the framework of these activities, we studied a strategy aimed at diversifying the water supply by identifying new exploitable aquifers in the area, to reduce the aforementioned problems. This paper presents the results of research carried out before and during the construction of the water well field “25 Ponti” located in the coastal area of the plain of Formia. The research consisted in laboratory analyses of 130 groundwater samples and in monitoring of piezometric trends. The data show a seasonal variation in groundwater chemical composition caused also by aquifer exploitation, which in some periods of the year affects the regulated reserves. This seasonal phenomenon was however present in absence of pumping.

Prevalence of pesticides in Krško-Brežice polje aquifer

Groundwater pollution with pesticides is a problem that occurs all over the world as well as in Slovenia. Considering the past high loads of groundwater with pesticides, the purpose of the presented research was to determine the presence of pesticides in the groundwater of Krško-Brežiško polje in the period 2018-2019 and to check the applicability of the passive sampling method. A total of 21 groundwater samples were taken at 11 locations and 2 samples each in the Sava and Krka rivers. We identified 15 pesticides and their degradation products. Atrazine and its degradation product desethylatrazine were most frequently determined in groundwater samples. They are followed by desethylterbutylazine, terbutylazine, metolachlor and simazine. Atrazine, desethylatrazine, chlortoluron, metolachlor and terbuthylazine were detected in surface water. A total of 24 samples were taken in groundwater and surface water using the qualitative passive sampling method. We singled out 8 pesticides that appear in two campaigns. The frequency and occurrence of individual pesticides by both methods are comparable. Passive sampling has proven to be an appropriate method of identifying the presence of pesticides. The highest loads in the Krško-Brežiško field arise from the agricultural land areas. Groundwater is more contaminated with pesticides in the central part of the field in the direction of groundwater flow from west to east. In the groundwater of the Krško-Brežice field, atrazine and desethylatrazine are still the most frequently detected pesticides with higher concentrations, despite a 20 years long ban on the use of atrazine-based plant protection products.