Total Dissolved Solids Range Research Articles

Assessment of water quality from selected borehole locations in Ado Ekiti, Ekiti State, Southwest Nigeria.

Borehole water is commonly believed to be pure and safe to drink. The present study assessed the quality of ten selected borehole locations within Ado -Ekiti. This was carried out by assessing the physicochemical parameters, microbial and heavy metal contamination using standard procedures. The physicochemical parameter results showed that Temperature range between 25.99 oC - 26.60 oC, Electrical conductivity range between 41.62 µs/cm - 202.54 µs/cm, pH range between 6.81-7.57, Total dissolved solids range between 28.15 mg/L - 116.22 mg/L, Total suspended solids range between 0.09 mgl -1.27 mgl, Turbidity range between 0.12 NTU-0.71 NTU, Total Hardness range between 29.64 mg/l -80.61 mg/l, Total Alkalinity range between 20.97 mg/l - 65.42 mg/l and all values were within World Health Organisation (WHO) permissible limits. The bacteria count of borehole water sample range from 10.66 ± 0.03 Cfu/ml to 12.56 ± 0.03 Cfu/ml. Highest fungi count of the borehole water sample was in the value range from 8.27 ± 0.00 Sfu/ml to 9.63 ± 0.02 Sfu/ml. The highest coliform detected in the borehole sample range from 5.33 ± 0.58 Cfu/ml to 8.67 ± 8.56 Cfu/ml. The bacteria, fungi and coliform count result observed in this study was higher than the WHO recommended limits. The metals occurred in the samples in this order Cr >Fe > Pb > As > Cd. The heavy metals were present in quantities higher than WHO recommended limit in some of the samples which is an indication of potential health hazards through the water consumption.

Evaluating the groundwater quality in Northern Tarim Basin by resistivity inverted from magnetotelluric data

Groundwater is a potentially significant resource for agricultural and industrial uses in Tarim Basin, the largest arid endorheic basin in China. Hydrogeochemical and hydrogeologic researches have provided detailed information of groundwater chemical type, composition, ion content and flow. However, there is lacking in quantitative estimation of groundwater in whole basin scale subject to the limits of samples as well as the unclear underground structure. To address the problem, 3-D electrical resistivity model constructed from inversion of magnetotelluric (MT) data was used to calculate the Total Dissolved Solids (TDS) of groundwater based on previous experimental studies and empirical equations. The TDS model shows relatively high value in the east of the study area and in deep, primarily controlled by depth, flow direction, stratigraphy, and water table gradient. Groundwater can be classified into five categories in terms of TDS range in Standard for Groundwater Quality. Finally, the volume of each type and average available quantity of Classes I ∼ III (TDS < 1 g/L) per person were estimated by taking account of population distribution. Mapping groundwater TDS and volume reveals that human activities also play a role in groundwater salinity. The evaluation of groundwater quality and volume based on TDS provides a basis for future urban construction and development as well.

An overview of water quality within the Colombo Municipal Council area; A retrospective report analysis

Access to safe and quality drinking water is a fundamental requirement and a basic human right. Water quality is determined by its biological, physical, and chemical properties. Colombo Municipal Council (CMC) area consists of the largest population who utilize pipe-borne water supplied by the National Water Supply and Drainage Board (NWS&amp;DB) Sri Lanka. The objective of the study was to assess the water quality of the drinking water under selected parameters within the Colombo Municipal Council area. In this quantitative, retrospective, cross-sectional study, 268 water analysis reports from 1st July to 30th November 2021 were considered with the permission of the Ethics Review Committee of KIU (KIU_ERC_21_194A) and relevant authorities of NWS&amp;DB. Data on selected parameters such as color, turbidity, pH, Total Dissolved Solids (TDS), Free Residual Chlorine (FRC), the total number of coliform bacteria, and the total number of Escheretia-Coli (E-Coli) were extracted. Data analysis was done using SPSS (Version 25). All values were considered based on reference ranges of Sri Lanka Standards (SLS) guidelines. The study indicated that, among nine water schemes and four water reservoirs, the highest contributions for purification were from the Maligakanda water scheme (15.9% n =56) and Maligakanda water reservoir (51.6%, n=139). All the samples were fully treated water and the mean of the color was 4.03 Hazen Units which was within the permissible level, though ( 3.7 % n=10) of samples exceeded the range. The mean value of the turbidity was 0.49 Nephelometric Turbidity Unit (NTU) which was within the permissible level and only one sample had deviated from the maximum permissible level. The mean pH value was 7.33 and except for one, all other samples were within the permissible level. The mean value of the TDS was 24.51mg/L and the majority (95.8 %, n= 257) of FRC values varied between 0.6-0.8mg/L which was within the permissible level, while 3.39% (n=10) of samples had 0 mg/L. All samples were free from coliform and E-Coli. Most of the samples were within the permissible range of color, pH, turbidity, TDS, FRC, and free from Coliform and E-Coli which can be recommended for use.

Compositional Analysis of Conventional and Unconventional Permian Basin-Produced Waters: A Simple Tool for Predicting Major Ion Composition

Summary Treatment methods for produced water (PW) are significantly affected by a high concentration of total dissolved solids (TDS), a summation of dissolved organic and inorganic compositions. Understanding the constituents of TDS to eliminate or prevent chemical reactions is critical in the design optimization of the treatment processes. In this paper, two PW geochemical data sets generated from conventional and unconventional reservoirs in the Permian Basin were analyzed to correlate constituents with TDS. Compositional data sets from over 115,000 PW samples originally reported by the U.S. Geological Survey (USGS) and 45 oil and gas operations were analyzed. Data preprocessing, culling, systematized- and meta-analysis, and statistical techniques were adapted to associate the data. Subcompositional geochemical data were transformed into isometric log ratios and are presented in bivariate and multivariate plots. Results indicate that Na+ and Ca2+ were the dominant cations and Cl− was the dominant anion. No observable trend differences in the Na+, Cl−, Ca2+, Mg+, and SO42− concentrations between PW from conventional and unconventional wells were registered. Variations in the isometric log ratio of Na/Cl and Ca/SO4 with TDS revealed that Na/Cl was nearly constant over the range of TDS, suggesting mineral buffering or a lack of significant water/rock reactions involving Na and Cl, and that Ca/SO4 increased with TDS, indicating that low-salinity fluids may have dissolved anhydrite producing a value near zero, with Ca gain and/or SO4 loss with increasing salinity. In all 10 counties and 8 formations investigated in this work, the ln (Ca/SO4) denotes Ca gain/SO4 loss relative to their composition in anhydrite or Permian seawater. Likely mechanisms leading to elevated ln (Ca/SO4) include sulfate reduction, dolomitization of calcite, Na/Ca cation exchange, albitization, and anhydrite precipitation from Ca-rich fluids. Results from this work are important as it is revealed that Ca/SO4 and Na/Cl can potentially be predicted from PW TDS concentrations. This information was combined to create a reservoir or location-specific model to estimate Na, Cl, Ca, and SO4 concentrations in Permian Basin PW, a powerful tool to improve treatment and reuse options in areas with few direct data.

Isotopic signatures and hydrochemistry in assessing groundwater occurrence in the desert environs west Qena, Egypt

BackgroundDeveloping the desert zone outside the flood plain of the Nile River and targeting the reclamation of about 12,500 feddan in the desert environs of Qena governorate are considered one of the top priorities of both government and the private sectors. The present study is based on qualitative analyses of the groundwater of the Quaternary aquifer in the desert environs west Qena. Groundwater was chemically and isotopically analyzed to determine the origin of groundwater and assess its occurrence.ResultsThe obtained results indicate that the Quaternary aquifer represents the most important groundwater aquifer in the area. The water level ranges from + 40 to + 67 m above sea level. The groundwater movement direction in the study area is mainly from southeast to northwest direction, with some local flow groundwater directions from Nile River at the north to old alluvial plain and desert environs at the south. The hydraulic conductivity of the aquifer is determined from the pumping test range from 17.63 to 42.86 m/day, with an average value of 27.04 m/day, while the transmissivity ranges between 2142.8 and 1128.3 m2/day, with an average value of 1456.74 m2/day. The total dissolved solids range from 589 to 3832 mg/L. Isotopic analysis (oxygen eighteen and deuterium) of fifteen groundwater samples was carried out to define the recharge source of the Quaternary aquifer. The groundwater isotopic data reflect variability in recharge conditions during different ages and different climatic regimes. According to the minor and trace elements concentration and US Salinity Laboratory Staff nomogram, most water samples are suitable for drinking purposes, domestic use and irrigation.ConclusionThe current research concluded that from the foregoing hydrological study and the determined values of hydraulic conductivity and transmissivity, the Quaternary aquifer is classified as ranging between moderate and high potential aquifer. The high potentiality of the aquifer is detected close to the Nile River. In addition to the representative groundwater samples showing the isotope signature of the Nile River sample, this means that all these wells have the same source of recharge (meteoric water of the Nile River).

Forecasting water quality parameters using artificial neural network for irrigation purposes

This study was aimed at analyzing the water quality of Ele River Nnewi, Anambra State for irrigation purposes with a view to predicting a one-year water quality index using Artificial Neural Network (ANN). Water pollution has posed a major problem and identifying the points of pollution in the River system is a very difficult task. To overcome this task, the need to determine the pollution level arose by modeling and predicting four water quality parameters at four (4) different locations using the Artificial Neural Network. These parameters include the pH, Total Dissolved Solids (TDS), Electrical Conductivity (EC), and Sodium (Na), respectively. The water quality results showed that the pH values which ranges from 6.01 to 6.87 were within the FAO standard in all the points for both rainy and dry seasons, whereas the TDS (mg/l), EC (dS/m) and Na (mg/l) parametric values range from 2001 to 2506, 3.01 to 5.76, and 40.42 to 73.45 respectively, were above the FAO standard from point 1 to point 3 and falls within the FAO standard at point 4 with values ranging from 1003 to 1994, 2.01 to 2.78 and 31.24 to 39.44, respectively. However, during the dry season, the TDS, EC, and Na values range from 2002 to 2742, 3.04 to 5.82 and 40.14 to 88.45 respectively, were all above the FAO standard. Generally, the artificial neural network modeled the actual water quality data set very well with good prediction. The training model performance evaluation shows that the R2 values ranges from 0.981 to 0.990, 0.981 to 0.988, 0.981 to 0.989 and 0981 to 0.989, for pH, TDS, EC, and Na. The testing model performance shows that the R2 value ranges from 0.952 to 0.967, 0.953 to 0.970, 0.951 to 0.967and 0.953 to 0.968, for pH, TDS, EC and Na while the forecast performance evaluation shows that the R2 values ranges from 0.945 to 0.968, 0.946 to 0.968, 0.944 to 0.967 and 0.949 to 0.965 for pH, TDS, EC and Na respectively. It was also observed that the Root Mean Squared Error (RMSE) ranges from 0.022 to 0.088, 0.012 to 0.087, 0.015 to 0.085 and 0.014 to 0.084 for pH, TDS, EC and Na, respectively. Information from this study will serve as a guide to researchers on the water quality index for irrigation purposes. Also, it will guide the government and agencies on policy, management and decision-making on water resources.

Assessment of Groundwater Quality: A Sample Study of Selective Drinking Water Sources in Diplo Area of Sindh

The present study aimed to determine the quality parameters of underground drinking water found in Diplo, a sub-district of Tharparkar. The quality parameters examined in the water samples were pH (acidity), total dissolved solids (TDS), and electrical conductivity (EC). A total of 20 samples were randomly collected from different sources of drinking water, namely dug well and hand pump, from the study area. The results showed that the quality parameters of water samples taken from the hand pump were not within the appropriate range (pH range was 5.7-6.0 and TDS range was 1579-2120 mg/L), while those of well water samples were within range (pH range was 5.09-6.60 and TDS range was 497-1182 mg/L). Therefore, it was concluded that water from the well sources was safe for consumption as per the guidelines set by WHO and EPA and could be used for drinking purposes. The findings revealed that water from the hand pump sources had high TDS and EC (greater than WHO limit), which pose several health risks. It was noted that TDS is directly proportional to electrical conductivity and inversely proportional to the pH level of water. Further, it was recommended that future studies need to be conducted at regular intervals to evaluate the quality of drinking water in rural areas of Sindh province, so that authorities can promptly provide solutions to such issues.&#x0D; Copyright (c) The Authors

Geochemical Survey of low- temperature geothermal resource of the Reşadiye Spa (Tokat, Northern Turkey)

The low-temperature geothermal area of Reşadiye is located within the Kelkit Valley in the middle of the Black Sea region of Turkey. The area is covered with widespread travertine deposits which are acquired immediately on deposition from hot spring waters. Thermal waters have temperatures between 42 °C and 49 °C and the discharge rate is 3 L/sec. Total dissolved solids range from 3686 to 4204 mg/L. These thermal waters are of Na-HCO3-Cl type. A geothermal reservoir having probable temperature of about 100° is the source of thermal water for the springs. Before emerging along the margins of exposed carbonate formations through the faults and fractures, the waters interacts sometimes with Na-rich Neogene sediments and/or with B-rich rising geothermal fluids as confirmed by high concentrations of Cl, and, to a greater degree, by the presence of B. The conductive process along with the mixing of thermal waters with shallow groundwaters is the main cooling mechanism. Deuterium and oxygen-18 signatures of thermal groundwater indicate its meteoric origin. Equilibrium states of the Reşadiye thermal waters studied by means of the Na–K–Mg triangular diagram, K–Mg–Ca geoindicator diagram, and finally the activity diagrams in the systems composed of Na2O–CaO–MgO-K2O–Al2O3–SiO2–CO2–H2O phases indicate that the springs and low-temperature geothermal well waters in the area can be classified as shallow or mixed waters which are likely to be equilibrated with muscovit at temperature similar to those calculated from the chemical geothermometers. It was also observed that mineral equilibrium in Reşadiye waters is largely controlled by CO2 concentration. Based on acquired data, a conceptual model of the geothermal system of Reşadiye is proposed.

The Continental Intercalaire groundwaters of the Tidikelt (In-Salah region, Algeria). Hydrochemical and isotopic features

ABSTRACT The Continental Intercalaire (CI) groundwaters of the Tidikelt (In-Salah region) are characterized by a high salinity and ion concentrations higher than the maximum standards for drinkability. The total dissolved solids range from 850 to 3390 mg L–1 for conductivities ranging from 1470 to 6780 μS cm–1. Their chemical facies is dominated by Cl–, SO4 2– and Na+, respectively. Alkali ions, Cl– and SO4 2– are acquired through the dissolution of Halite (NaCl) and Gypsum (CaSO4, 2H2O). CI waters have depleted δ values for 18O and 2H, corresponding to a cold end-member. This is an indication of a very homogeneous aquifer which is similar to what was observed for the CI in the eastern sub-basin (Great Oriental Erg) and for palaeowaters elsewhere in the Middle-East and Libya. Tritium analyses show that these waters are all very weakly tritiated, which is a testimony of the non-renewed character for these waters. Both δ 13C and 14C measured on more than a dozen of samples also show that CI groundwaters are old, with ages comprised between 19,000 and 35,000 years with an average δ 13C of –10 ‰. This means that these waters are derived from old precipitation whose features were totally different from the very scarce prevailing ones.

Appraising the risk level of physicochemical and bacteriological twin contaminants of water resources in part of the western Niger Delta region

This study was carried out to assess the physicochemical and bacteriological contaminants of surface, shallow well and municipal borehole waters in part of the western Niger Delta as a way of safeguarding public health against waterborne diseases. A total of 72 water samples collected from the study area were analysed and their results show that the pH average value ranges from 6.2 in the dry to 8.5 in the rainy seasons for surface water, 6.6 and 8.3 for shallow well water and 6.5 to 8.4 for borehole water. The turbidity in surface water varies from 8.1 to 26.2 Formazin Attenuation Unit (FAU), 0.3 to 2.9 FAU in shallow well water and 0.4 to 4.8 FAU in borehole water. Electrical conductivity (EC) value varies from 1010 to 1840 μs/cm for surface water, 201 to 950 μs/cm for shallow well water and 670 to 1650 μs/cm for borehole water. Total dissolved solids range from 0.1 to 2.6 mg/l in surface water, 0.2 to 4.1 mg/l in shallow well water and 0.3 to 4.4 mg/l in borehole water. The value of the total hardness ranges from 44 to 120 mg in surface water, 46 to 96 mg in shallow well water and 70 to 130 mg in borehole water. The nitrate value ranges from 1.1 to 10.6 mg in surface water, 3.0 to 8.4 mg in shallow well water and 3.7 to 9.6 mg in borehole water. The value of sulphate content varies from 4.6 to 38.5 mg in surface water, 6.2 to 34.8 mg in shallow well water and 5.7 to 55.7 mg in borehole water. The value of phosphate concentrations in surface water varies from 1.0 to 9.0 mg, 0.7 to 3.4 mg in shallow well water and 1.0 to 4.7 mg in borehole water. The bacteriological analysis using the membrane filtration technique revealed the presence of faecal bacteria and total coliform counts. The presence of the analysed twin contaminants in the studied water resources reduced their water quality. The physicochemical and bacteriological data were subjected to statistical and correlation tests. It was concluded that their concentration levels were independent of intra-seasonal changes. The likely natural and artificial sources of contaminants are run-offs from fertilized lands, septic tanks, industrial discharges, sewage and waste disposal, algae blooms and erosion from natural deposits. The inherent risk is water-related diseases such as waterborne diseases, water-washed diseases, water-based diseases and diseases transmitted by water-related insect vectors. Water resources should be protected through proper sanitation systems, limiting of up-stream discharges, maintenance of wellheads, boiling and municipal water treatment plants. Educational advice should be given to the inhabitants on the dangers posed by continuous drinking of contaminated water. These measures will prevent disease outbreak and public health burden in the area.

HONEY INFLUENCE ON THE PHYSICOCHEMICAL CHARACTERISTICS OF WATER AND TEAS

The combination of honey with tea or honey with water is one of the most traditional flavour improvement, nutrition and therapy. The aim of the study was to determine the influence of different types of honey on selected physicochemical properties of water and teas. For experimental purposes, we used 50 types of polyfloral honey obtained from different regions of Ukraine. For testing, we used 5 g of honey, which was mixed in 100 ml of water or tea prepared from dried inflorescences Sambucus nigra L. Using the EUTECH equipment, we determined the pH, electrical conductivity (EC) and total dissolved solids (TDS) content in each sample. In the samples water with honey we determined pH in the range from 6.82 (WH-16-01) to 7.70 (WH-16-25), electrical conductivity ranging of 424.0 (WH-16-30) to 545.0 (WH-16-37) μS·m -1 , and content of total dissolved solids range of 252.00 (WH-16-01) to 344.00 (WH-16-47) mg.l -1 . In the samples tea with honey we determined pH ranging of 6.84 (TH-16-01) to 7.56 (TH-16-24; HT-16-25; TH-16-48; TH-16-49 TH-16- 50), electrical conductivity with values from 555.00 (HT-16-02) to 1450.00 (HT-16-01) μS·m -1 , and content of total dissolved solids in the range from 350.00 (TH-16-02) to 913.00 (TH-16-01) mg.l -1 . Correlation analyses between the evaluated physicochemical parameters of water and teas by the addition of various honey have unambiguously demonstrated significant differences between honey samples, which is explained by the fact that the honey has a different plant origin, and hence a different chemical composition.

Evaluation and characterization of groundwater of the Maastrichtian Lafia formation, Central Benue trough, Nigeria

Hydrochemical assessment of groundwater in the Lafia formation, Central Benue trough, Nigeria was carried out with the aim of determining its quality for domestic and irrigation purposes. Thirty groundwater samples from boreholes and hand-dug wells were analyzed using atomic spectrometry and titrimetric methods. The water quality index (WQI) was evaluated from physicochemical parameters and used in assessing the groundwater quality for drinking, while the electrical conductivity (EC), percentage sodium (%Na), sodium absorption ratio (SAR) and magnesium hardness (MH) were evaluated to assess its suitability for irrigation. The physico-chemical parameters in order of dominance are \(\hbox {HCO}_{3}^{-} >\hbox {NO}_{3}^{-}>\) Cl- > \(\hbox {PO}_{3}^{-} >\hbox {SO}_{4}^{2-}\) for the anions and \(\hbox {Fe}^{3+}>\hbox {Na}^{+}>\hbox {Ca}^{2+}>\hbox {Mg}^{2+}>\hbox {Pb}^{2+} >\hbox {K}^{+}\) for the cations. The pH indicates acidic to weakly alkaline water (5.1–7.3); EC ranges from 110 to 1396 \(\upmu \)S/cm, while the total dissolved solids range between 136.9 and 3.4 mg/l, based on which it is classified as freshwater. WQI showed that only 40% of the groundwater samples are suitable while 60% are unsuitable for drinking and will therefore require treatment. Three water facies: \(\hbox {Ca}^{2+} + \hbox {Mg}^{2+}, \hbox {Ca}^{2+} + \hbox {Na}^{+} + \hbox {K}^{+}\) and \(\hbox {HCO}_{3}^{-}\) characterized the area indicating the groundwater-quality situation. Based on EC classification, 33.33% of the water samples are considered excellent, 60% as good, 6.67% as permissible while on the basis of %Na, only 13.34% are unsuitable for irrigation. SAR of 96.67 and 3.33% of the groundwater samples indicate excellent and doubtful waters, respectively. 93.4% of groundwater samples has MH < 50 and are considered suitable for irrigation.

Assessment of Chaves Low-Temperature CO2-Rich Geothermal System (N-Portugal) Using an Interdisciplinary Geosciences Approach

This paper reviews the results of a multi- and interdisciplinary approach, including geological, geomorphological, tectonic, geochemical, isotopic, and geophysical studies, on the assessment of a Chaves low-temperature (77°C) CO2-rich geothermal system, occurring in the northern part of the Portuguese mainland. This low-temperature geothermal system is ascribed to an important NNE-trending fault, and the geomorphology is dominated by the “Chaves Depression,” a graben whose axis is oriented NNE-SSW. The study region is situated in the tectonic unit of the Middle Galicia/Trás-os-Montes subzone of the Central Iberian Zone of the Hesperic Massif comprising mainly Variscan granites and Paleozoic metasediments. Chaves low-temperature CO2-rich geothermal waters belong to the Na-HCO3-CO2-rich-type waters, with pH≈7. Total dissolved solids range between 1600 and 1850 mg/L. Free CO2 is of about 500 mg/L. The results of SiO2 and K2/Mg geothermometers give estimations of reservoir temperature around 120°C. δ18O and δ2H values of Chaves low-temperature CO2-rich geothermal waters indicate a meteoric origin for these waters. No significant 18O-shift was observed, consistent with the results from the chemical geothermometry. δ13CCO2 values vary between −7.2 and −5.1‰ vs. V-PDB, and CO2/3He ratios range from 1×108 to 1×109, indicating a deep (upper mantle) source for the CO2. 3He/4He ratios are of about 0.9 (R/Ra). The Chaves low-temperature CO2-rich geothermal waters present similar 87Sr/86Sr ratios (between 0.728035 and 0.716713) to those of the plagioclases from granitic rocks (between 0.72087 and 0.71261) suggesting that water mineralization is strongly ascribed to Na-plagioclase hydrolysis. Geophysical methods (e.g., resistivity and AMT soundings) detected conductive zones concentrated in the central part of the Chaves graben as a result of temperature combined with the salinity of the Chaves low-temperature CO2-rich geothermal waters in fractured and permeable rock formations. This paper demonstrates the added value of an integrated and multi- and interdisciplinary approach for a given geothermal site characterization, which could be useful for other case studies linking the assessment of low-temperature CO2-rich geothermal waters and cold CO2-rich mineral waters emerging in a same region.

Isotopic composition and content of coalbed methane production gases and waters in karstic collapse column area, Qinshui Coalfield, China

The Qinshui Coalfield is one of the most important coalbed methane (CBM) coalfields in China with vast CBM resources, in which the Carboniferous Taiyuan Formation is one of the main coal-bearing sequences. Eleven CBM production gas samples and associated production waters were collected from the Taiyuan Fm. in the karstic collapse column (KCC) area of Sijiazhuang mining area, Qinshui Coalfield. The gas molecular and isotopic compositions and water quality, water carbon and hydrogen isotope compositions were analyzed. Results in this study reveal that CBM from Taiyuan Fm. of Sijiazhuang is dominated by CH4 (95.9–99.4mol%, air-free basis) with minor amounts of N2 (average: 1.07%), CO2 (average: 0.25%), and ethane (average: 0.02%). The carbon isotope ratios of the production CH4 range from −40.8‰ to −33.2‰, with an average of −37.1‰, and the corresponding hydrogen isotope ratios of CH4 −196‰ to −178‰, with an average of −186‰ (n=11). Thermogenic methane is the primary source of CBM from the Taiyuan Fm. of Sijiazhuang, and its estimated proportion is calculated to range from 72% to 95%.The type of CBM production water is Na–HCO3, and the concentrations of total dissolved solids range from 1282mg/mL to 1718mg/mL, with an average of 1417mg/mL. The δD values of the water samples range from −74.8‰ to −61.1‰, the δ18O values from −9.6‰ to −8.0‰. The isotope compositions of water samples fall to the right of the GMWL, suggesting a combination of fluid–rock interaction under high temperature conditions and evaporation.There is a good correlation between the distribution of KCCs and the isotopic compositions of CBM production gases and waters in the study area. KCCs in this area can be the free pathways going through the surface, the limestone beds and the 15# coal seam of Taiyuan Fm. KCC presence makes the CH4 carbon isotopic composition become more enriched in 13C in shallower areas, because of the stronger desorption–diffusion–migration isotope fraction effect of CBM in the north of Sijiazhuang mining area. In contrast, the δ13C1 and δ13CCO2 values are lighter in deeper areas in the southwest of the study area. This could be due to the stronger groundwater stripping process in that area. The results can be used for CBM exploration and exploitation in KCC areas.

Deciphering Groundwater Quality for Drinking and Irrigation Purposes – A Study in Lefunga Block of West Tripura District, Tripura, India

The aim of the present study is to assess the groundwater quality of Lefunga block, west Tripura district, Tripura, for irrigation and domestic purposes. Nine samples were collected from bore wells used for drinking and irrigation purposes. The water samples were analyzed for major cations like calcium, magnesium, sodium, potassium, iron and anions like chloride, bi-carbonate and sulfate. Samples were also analyzed for arsenic and fluoride concentration. The important constituents that influences water quality for irrigation such as Electrical conductivity (EC), Total Dissolved Solids (TDS), Sodium Adsorption Ratio (SAR), Magnesium Adsorption Ratio (MAR), Soluble Sodium Percentage (SSP) and Permeability Index (PI) were determined and compared with standard limits. The values of TDS range from 29.33 – 86.00 mg/L, SAR values range from 0.04 – 0.07, MAR values range from 33.56 – 53.68 and SSP range from 3.01 – 5.87. Results show that they all lie within the safe limits and thus largely suitable for irrigation purpose. Hence, the groundwater of this area is free from salinity hazard and has no adverse effect on soil properties. Furthermore, the water samples also fall within recommended limits and are found suitable for drinking purposes except one sample having high levels of iron and thus rendering it to be very poor for drinking purposes as per WQI classification.

Biocorrosion Study of Mild Steel in Dumpsite Leachates

Biocorrosion due to dumpsite leachates can lead to rupture and failure of engineering materials such as mild steel. This study was carried out to assess the effect of dumpsite leachates in corrosion process of mild steel. Mild steel coupons were prepared and immersed completely in leachates from Olusosun dumpsite (A), Ewu Elepe dumpsite (B) and Abule Egba dumpsite (C). The following parameters were measured at regular interval in each of the leachate: Total Dissolved Solids (TDS), Conductivity, pH, Temperature and Dissolved Oxygen (DO) using a multi – parameter water quality monitor and Total Bacterial Count (TBC) using standard method for biological analysis of water flood injection water. The corrosion rate was determined using weight loss method. The results revealed that the weight loss varied between 0.27 and 0.58 g in leachate A, between 0.05 and 0.29 g in leachate B and between 0.02 and 0.50 g in leachate C. Corrosion rate varied between 2.35 and 7.61 mm/yr in leachate A, between 1.15 and 1.48 mm/yr in leachate B and between 1.48 and 7.03 mm/yr in leachate C. Leachate A has the highest range of TDS ranging between 18, 686 and 125, 856 mg/L as well as highest range of Conductivity ranging between 8.62 and 57.75 µS/cm. Moreover, leachate A has the highest range of pH ranging between 5.11 and 5.34 while it has the least range of DO varying between 2.94 and 3.59 mg/L. Leachate B has the highest range of temperature varying between 27.60 and 32.30°C. Leachate C has the least range of TBC ranging between 100 x 103 and 126 x 103 Cfu/ml. The leachates from dumpsites have the potential to cause corrosion of mild steel due to the presence of bacterial in the leachates. It was recommended that dumpsites should not be cited where there are pipelines.

Quantitative Assessment of the Chemical Safety of Groundwater Wells in Two Selected Districts of Rwanda

This research was conducted on groundwater wells of Bugesera and Muhanga districts in Rwanda where its physico-chemical parameters were determined as main aim. The study period was between February and May, 2015. A total of 18 water samples were collected from 12 sites. The laboratory experiment focused on the following quantitative determination parameters: Turbidity, pH, Temperature, Electrical Conductivity (EC), Total Dissolved Solids (TDS), Iron, Zinc, Manganese, Nitrate, and Phosphate. Alkalinities (range from 153 to 224 mg/l) in all studied wells were above the standard. Except in one well above the standard, Zinc was detected below the standard in all wells (0.01 up to 0.3 mg/l). Except one well below the range, Iron was found within the normal range in all wells (0.005 – 1.00 mg/l). Manganese was within the normal range in five wells of Bugesera district (0.122 – 0.420 mg/l), whereas below the WHO standard in all wells of Muhanga district (0.003 – 0.087 mg/l). Except one well in Bugesera district all heavy metals in all wells were not exceeded the permissible limits. The samples from Kanogo groundwater well were containing a very high amount of Zinc and Manganese. In some wells detection were found below the standard. TDS (range from 70.5 to 232mg/L), pH (range from5.5 to 6.3) and Electrical conductivity (range from 128 to 335 μs/cm) values in all studied wells were lower than standards provided by Rwanda Bureau of Standards (RBS) and World Health Organization (WHO). This study provides an insight on the quantitative measurements of some chemicals which do have relevance in the use of groundwater wells for domestic consumption. The wells can be utilized with proper management and regular monitoring. However, due to the high amount of heavy metal pollutants in the Kanogo groundwater well of Bugesera district this well should be monitored and treated for the moment. The government and other stakeholders together with the community should seek an alternative safe water supply source. Some preventive measures like planting trees around the well to protect it against entry discharge of residual waste and periodically cleaning of the wells are suggested. It is also important to sensitizing the community so that they can take precautionary measures to the cause; extent and impact of the contamination by these chemicals.

Characterisation of the physicochemical qualities of a typical rural-based river: ecological and public health implications

The physicochemical qualities of a typical rural-based river were assessed over a 12-month period from August 2010 to July 2011 spanning the spring, summer, autumn and winter seasons. Water samples were collected from six sampling sites along Tyume River and analysed for total nitrogen, orthophosphate, biochemical oxygen demand (BOD), temperature, pH, dissolved oxygen (DO), electrical conductivity (EC), total dissolved solids (TDS) and turbidity. BOD regimes did not differ significantly between seasons and between sampling points and ranged from 0.78 to 2.76 mg/L across seasons and sampling points, while temperature ranged significantly (P < 0.05) between 6 and 28 °C. Turbidity varied significantly (P < 0.05) from 6 to 281 nephelometric turbidity units while TDS (range 24–209 ppm) and conductivity (range 47.6–408 mg/L) also varied significantly (P < 0.05) across sampling points with a remarkable similarity in their trends. Orthophosphate concentrations varied from 0.06 to 2.72 mg/L across seasons and sampling points. Negative correlations were noted between temperature and the nutrients, DO and temperature (r = −0.56), and TDS and DO (r = −0.33). Positive correlations were noted between TDS and temperature (r = 0.41), EC and temperature (r = 0.15), and DO and pH (r = 0.55). All nutrients were positively correlated to each other. Most measured parameters were within prescribed safety guidelines. However, the general trend was that water quality tended to deteriorate as the river flows through settlements, moreso in rainy seasons.

Value of information methodology for assessing the ability of electrical resistivity to detect CO2/brine leakage into a shallow aquifer

Subsurface sequestration of CO2 has uncertainties and potential consequences. Decision analysis and the value of information (VOI) can aid in (1) linking subsurface uncertainty to economic outcomes and (2) determining when additional information may be useful before making further decisions. This study uses an uncertainty quantification (UQ) evaluation of CO2 and accompanying brine leakage into a shallow aquifer via an abandoned wellbore from a deep reservoir to demonstrate both of these functions.First, we equate the range of TDS (total dissolved solids) plume results into a range of possible economic outcomes from a decision for an agricultural application of the resource, where the groundwater is used to irrigate corn crops, and therefore high saline concentrations result in economic losses. We use the concept of perfect information and these risk quantification results to identify that any information source will be only relevant when considering plumes which exceed 2000ppm concentration. Next, we provide a physics-based methodology to calculate the reliability of electrical resistance data to detect pH/brine plumes. We simulate the electrical resistivity response for all of the leak simulations from the UQ study. This gives us the information reliability which, along with the economic outcomes, is used to calculate the value of imperfect information (VOIII). The calculated reliabilities demonstrate that electrical resistivity generally can determine the existence of a plume but it cannot perfectly determine if the plumes’ concentration is ≥2000ppm. We present VOIII measures for three different electrical resistivity field acquisitions that vary in their distance to the leaking wellbore.

Investigation of physicochemical characteristics and heavy metal distribution profile in groundwater system around the open dump site

In this study, the characterization of solid waste and the effect of the leachate from an open dumping site in Ariyamangalam, Tiruchirappalli District, Tamil Nadu, on groundwater is investigated. A total of 14 groundwater samples and 20 leachate samples were collected for monitoring purpose. All the samples were analyzed for various physical and chemical parameters according to standard methods: this includes pH, electrical conductivity, total dissolved solids (TDS), total hardness, and total alkalinity, major cations such as Ca2+, Mg2+, and Fe2+, major anions such as NO3−, Cl−, and SO42− and heavy metals such as Cd, Cu, Mn, Pb, and Zn. The results indicated that, very few parameters such as pH, sulfates and nitrates concentration in the groundwater samples are within the recommended maximum admissible limits approved by WHO (World Health Organization 940–949, 2002) and Bureau of Indian standards (IS 10500:1991). The TDS (range between 740 and 14,200 mg/L) in groundwater reveal the saline behavior of water and was found to be very high according to standards. The range of chlorides in all the locations under investigation is 215.15–4,098.73 mg/L. The contour plots also indicated that the groundwater was rigorously contaminated with various heavy metals. The presence of high concentration of Pb (0.59 mg/L) in groundwater samples nearby dumping site implies that groundwater samples were contaminated by leachate migration from an open dumping site.