High Altitude Lake and Hydrochemistry: A Study of Lam Dal and Six Consecutive Lakes of Dhauladhar, Himachal Himalaya, India

Increased human influence has warmed the atmosphere, ocean and land thereby resulting in widespread and rapid changes in the atmosphere, ocean, cryosphere and biosphere (IPCC, 2021). High altitude lakes are generally small and quite sensitive to natural and anthropogenic perturbations. The present work is a preliminary work to investigate different hydro chemical processes and factors that controls the geochemistry of a high altitude lake, Lam Lake (dal) and its consecutive six lakes flowing through the Chamba district, Himachal Pradesh. Two hundred and eighty (n=280) water samples were collected in the year 2017 during the pre-monsoon and post-monsoon season. The anion concentration for all the seven lakes followed the trend HCO3- > NO3- > Cl- > SO42- > PO43- whereas the order of cation concentrations was Ca2+> Mg2+> Na+> K+ for both the seasons. Less EC of the water samples shows its serene nature. Components of bicarbonate (HCO3-) were found to be the major anion whereas calcium (Ca2+) was found to be the major cation present in the lakes. Piper Plot and Durov plot indicated Ca2+ – HCO3- as the major hydrogeochemical facies with comparatively less contribution from Mg2+–HCO3- type. The dominance of Ca2+ – HCO3- over Mg2+– HCO3- reflects the possibility of the natural order of dominance in the geology of the catchment area. The low Na+ + K+/TZ+ (total cations) ratios and the high Ca2+ + Mg2+/TZ+ (total cations) and (Ca2+ + Mg2+)/(Na+ + K+) ratios showed dominance of carbonate weathering. The average carbon ratios during pre-monsoon and post-monsoon were found to be 0.97 and 0.98, respectively, suggesting that proton is primarily derived from the oxidation of sulphide involving carbonate dissolution. The baseline data generated for a high-altitude lake shows that weathering and erosion during monsoonal precipitation and snow melt runoff during ablation season are the main sources of the chemical composition of lake water. Further to trace the imprints of climate change and seasonal variations in the high-altitude lakes, long term monitoring is recommended along with isotopic tracer techniques.

Hydrogeochemical Assessment of Groundwater Quality and its Suitability for Irrigation and Domestic Purposes in Rural Areas, North of Baiji City-Iraq

Background: The present study was conducted to highlight the importance of environmental pollution and its negative impacts on aquatic, plants and animals lives, especially in industrial areas. Objective: This research involved studying the hydrogeochemistry of the groundwater and assessing its quality for irrigation and domestic purposes using quality parameters. In this study, 33 groundwater samples were collected from wells during May 2013 and were analyzed for major ions and TDS. Results: The hydrogeochemical facies of groundwater were identified using the Gibbs model and Chloro – alkaline indices. The results of the Gibbs graph suggest that groundwater chemistry is controlled by evaporation factors. It was found that the values of chloro – alkaline indices were positive, indicating ionic exchange between Na+ in groundwater with Ca2+ and Mg2+ in the aquifer material. Conclusion: The current study of corrosivity ratio showed that groundwater wells are unsuitable for domestic uses.

Assessment of seasonal groundwater quality using CHIDAM software in Virudhunagar district of Tamil Nadu.

Hard rock aquifer is the most predominant in the southern peninsula exclusively in Tamil Nadu, India. Virudhunagar district is situated in the South west part of Tamil Nadu, mostly of hard rock topography. Groundwater plays a major role in this area contributing to domestic, irrigation and industrial practices. Running down of groundwater by extreme consumption and less recharge in the study area has reduced the level of groundwater. On the other hand, intensive domestic, agriculture and industrial practices impacts the quality of quality of groundwater as well. Hydro geochemistry plays an important role in evaluation of suitability of groundwater for its usage in several purposes. A total of 72 samples from North East Monsoon (NEM) and Post Monsoon (POM) has been analyzed hydrochemically. The irrigation quality parameters such as sodium adsorption ratio (SAR), %Na, Residual Sodium Carbonate (RSC), Kelley’s index and Magnesium hazard were calculated using CHIDAM software 2020 in conjunction with USSL and Doneen diagrams. During NEM, EC and TDS ranges from 273 to 5869 mg/L and 194 to 4159 mg/L and during POM is from 235 to 6850 mg/L and 233.8 to 6916 mg/L. The hydrogeochemical facies represents that Ca-HCO3 and mixed Ca-Mg-Cl facies are predominant during NEM and Na-Cl and mixed Ca-Mg-Cl are predominant during POM. The higher concentration of TDS and EC in the samples reflects the unsuitability of groundwater in both seasons.

Major ion composition and 87Sr/86Sr of groundwater in the coastal Gujarat alluvial plain, India

<p>Major ions, Sr concentration, and <sup>87</sup>Sr/<sup>86</sup>Sr have been analyzed in groundwater of the coastal Gujarat Alluvial Plain, collected during monsoon, post-monsoon, and pre-monsoon seasons of 2016–2017. The major objective of this study was to understand the regional groundwater salinization mechanism. In the study area, the groundwater is mostly characterized by Na-Cl facies, with few samples of Ca-Cl, Ca-Mg-Cl, Na-Ca-HCO<sub>3</sub>, and Ca-Mg-HCO<sub>3</sub> types. Whereas, the Narmada and the Tapi river water samples are particularly of Ca-Mg-HCO<sub>3</sub> type. The hydrogeochemical facies evolution (HFE) diagram depicts the coastal groundwater freshening irrespective of the season ruling out the lateral seawater intrusion far inland. However, the <sup>87</sup>Sr/<sup>86</sup>Sr and Br/Cl ratios strongly suggest the modern marine influence on the regional groundwater. In the plot of 1/Sr versus <sup>87</sup>Sr/<sup>86</sup>Sr, most of the groundwater samples fall on the binary mixing line between the seepage groundwater and modern seawater endmembers. Therefore, we suspect that the up-coning of recently trapped seawater by groundwater over-extraction is the most plausible reason for the groundwater salinization, which indicate the vulnerability of the coastal Gujarat alluvial plain to the near future sea ingress under the global warming scenario. A few exceptional groundwater samples far north of the Narmada River show more radiogenic <sup>87</sup>Sr/<sup>86</sup>Sr indicative of silicate weathering.</p>

Hydrogeochemical assessment of groundwater of Igboora Area, Southwestern Nigeria

The people of Igboora rely on groundwater for their domestic water supply. A hydrogeochemical study was carried out on twenty-seven groundwater samples collected from various boreholes across the study area to determine the suitability of the groundwater for drinking purpose. The total dissolve solids (TDS), electrical conductivity (EC) and pH of the water were measured in the field directly, while the concentrations of major ions were done in the laboratory using flame photometry and spectrophotometry methods. The hydrogeochemical facies classes was done with piper plot and the likely enrichment source(s) of the chemical facies were interpreted with Gibbs plot in conjunction with correlation analysis. The results showed that the pH was between 5.0 and 6.7 at an average (av.) of 5.8; TDS ranged from 50 – 280 (av. 183) mg/L and EC was 110 – 560 (av. 373) μS/cm. The concentrations of the major cations in mg/L were: 5 – 105.5 Ca2+, 1 – 11.9 Mg2+, 0 - 95 Na+, 0 – 112 K+, while for anions the ranges were, 9 - 58 HCO3 - , 6.8 – 28.8 CO3 2-, 1.1 – 29.4 SO4 2-, 2.9 – 26 Cl- and 16 – 90.5 for NO3 -. From the mean values, the order of the cationic dominance was Ca2+ > K+ > Na+ > Mg2+ while that of anionic was NO3 -> HCO3 - > CO3 2- > CI- > SO4 2- . The hydrogeochemical facies in the groundwater was mainly Ca-HCO3 type with minor occurrences of Na-HCO3 and Ca- Na-HCO3 types. Enrichment source of the cationic chemical facies was mainly rock dominated, while that of the anionic were from meteoric and biogenic sources. From the results of correlation analyses, the TDS has direct and positive relationships with most chemical constituents, indicating that the analysed ionic constituents dominated the dissolved solids in the groundwater. The groundwater can be said to be potable except that the water in the boreholes is slightly acidic and nitrate concentration exceeded recommended limit of 50 mg/L in many of the samples.

HYDROGEOCHEMICAL CHARACTERIZATION AND GROUNDWATER QUALITY APPRAISAL IN OKITIPUPA AND ENVIRONS, NIGERIA

The objectives of study was to determine hydrochemistry of groundwater in Okitipupa and environs to assess the quality of groundwater for drinking, domestic and irrigation. A total of 27 groundwater samples were collected randomly from different sources and analyzed for major cations and anions. The domination of cations and anions was in the order of K>Na>Ca>Mg and SO4>Cl >HCO3>NO3. The hydrogeochemical facies indicate three dominant facies: non-carbonate hardness exceeds 50 %; non-carbonate alkali exceeds 50 %; and transition zone with no one cation-anion pair exceeds 50 %, while precipitation is the dominant process in the hydrogeochemical evolution of the groundwater samples. The WQI calculated exhibits good (60 %) and poor (40 %) quality water for drinking and domestic purposes. For irrigation assessment, residual sodium carbonate values revealed good irrigation, permeability index values indicates suitable and marginal class, sodium absorption ratio, Kelly ratio, and %Na indicate good irrigation water. The processes controlling the groundwater chemistry are mixing of saline with fresh water and anthropogenic contamination; weathering and cation exchange; mineral precipitation/anthropogenic pollution; and groundwater dilution and mineral dissolution. Consequently the water is fairly suitable for drinking/domestic, and good for irrigation purposes.

Integrative Groundwater Studies in a Small-Scale Urban Area: Case Study from the Municipality of Penafiel (NW Portugal)

The occurrence of groundwater in urban hard rock areas is mostly controlled by secondary permeability caused by the fracturing degree and weathering grade. Vulnerability GIS-mapping, monitoring, and infiltration/recharge of water resources, and the delineation of the environmental protective background are key issues in evaluating, planning, managing, and decision-making for urban water systems. A small-scale urban area in Penafiel City was used as a case study. Historical and current scenarios were compared using hydrogeological GIS-based modelling. Water sources and potential contamination sources were mapped around the study area. Groundwater is mainly acidic, with a low mineralization and a Cl-Na to Cl-SO4-Na or Cl-Ca to Cl-SO4-Ca hydrogeochemical facies. Considering potential contamination sources, the moderate and the moderate-high classes dominate the area. The combined approach of the vulnerability indexes suggests that most of the area has a low to moderate vulnerability to contamination. The Infiltration Potential Index in urban areas (IPI-urban) indicates the prevalence of a low to moderate infiltration. Groundwater recharge evaluation indicates values < 2.3 mm/year and <60 mm/year for summer and winter scenarios, respectively. Finally, the investigation addresses insights for decision-makers for the appropriate planning and sustainable management of groundwater resources in small-scale urban areas.

Hydrogeochemistry of Ground Water in Mbeere South Sub-County, Kenya

This paper presents the experimental and simulated results of ground water in Mbeere South Sub -County, Kenya. A total of 30 samples from 10 boreholes were collected and used to investigate the chemical characteristics of groundwater. The samples were analyzed for physicochemical characteristics such as pH, temperature and Total Dissolved Solids along with major cations and anions using standard analytical procedures. The laboratory data obtained was run into a hydrogeochemical computer model, PHREEQC for aqueous speciation modelling. Origin pro and AqQA computer software were also used to reveal more hydrogeochemistry of the groundwater in the area. The results showed that the Na+ ˃ Ca2+ ˃ Mg2+ ˃ K+&gt; Fe3+were the dominant cations while HCO3-˃Cl-&gt;SO42-&gt;NO3-˃F- were the dominant anions. The hydrogeochemical facies indicated that 40% of the samples belong to the Ca2+-Mg2+-Cl--SO42- type, 40% belong to the Ca2+-Mg2+-HCO3-, 20 % are of the type Na+-K+-HCO3- with no Na+-K+-Cl--SO42- water type. The facies also illustrated atmospheric precipitation, dissolution of salt deposits within the vadose zones and weathering of halite, anhydrite, gypsum, huntite, hydromagnesite, artinite, dolomite and magnesite as the major contributors to the variation in Mbeere South groundwater chemistry. The Saturation Indices (SI) showed that the specimens were slightly saturated with aragonite, calcite, and dolomite; slightly under-saturated with anhydrite and gypsum; moderately under saturated with halite and under-saturated with hydromagnesite, trona and portlandite.