Effect of Chemical and Mineralogical Composition of Rocks on the Groundwater Chemistry of Hewanie and its Surrounding Areas, Southern Tigray, Ethiopia

The study was conducted in Hewanie and its surrounding areas of 169.82 km2 with a major objective of identifying the effect of chemical and mineralogical composition of rocks on the chemistry of the groundwater quality. This was conducted by taking 11 groundwater and 5 rock samples from the main geological units of the study area. Water samples were analyzed for major cations and anions, trace elements, TDS, total hardness, pH, electrical conductivity, and alkalinity the rock samples for major cations and anions and trace elements using AAS. The data was used to qualify and assess the quality of groundwater in the study area. Concentration of Ca2+, Mg2+, Na+, K+, HCO3-, Cl- and SO42- of groundwater samples in mg/l varied from 84 to 412, 96 to 211.2, 19.09 to 43.93, 2.34 to 51.09, 244 to 585.6, 71 to 340.8 and 49.49 to 122.5, respectively. Concentrations of Ca2+, Mg2+, Na+, K+, HCO3-, Cl- and SO42- of rock samples in ppm varied from 2586.4 to 28540, 2575.8 to 5289.6, 28.83 to 6134.9, 190.3 to 2379, 293.74 to 3717.6, 433.1 to 1143.1, 2787.8 to 27849.6, respectively. The predominant cations trend in both the groundwater and rock samples the study area was Ca2+ > Mg2+ > Na+> K+. Therefore, it is concluded that the local rock chemistry is seriously affecting the groundwater chemistry.Key words: Rock-water interaction, groundwater, rock, mineralogical composition, quality, Hewanie, Ethiopia

Impact Of Lamda Cyhalothrin Pyrethroid Insecticide On The Uptake Of Cations And Anions By The Gills Of Freshwater Catfish Hybrid Juvenile

The impact o acute exposure of karate (Lambda cyhalothrin pyrethroid) insecticide was evaluatedin a 4 – day exposure period at 20, 40, 60 and 80 ppm to Heterobranchus bidosals(+) X Clarias gariepinus(&#9794;) fngerlingsshowed the 96-hlc 50 as 25.11 ppm. The threshold value was 25. 11 ppm. The gills of the exposed fish analyzed showed a significant decrease in all major cations and anions(C1-, Ca2+, Na+, K+, Mg2+) at P < 0.05). There was no inhibion of upake of the catons and anions (C1-, Ca2+ Na+, K+, Mg2+). Their uptakeincreased rapidly during the 24 hr period and dropped at 48hr and 72 hr and gradualy increased at the end of 96 hr showing that it was time dependent. During the exposure period the fish stood in upright position with their snouts above the water surface gasping for air. Other behavioral characteristics of the exposed fish were peeling of the skin, initial increase in opercula movement, curvature of the body, loss of balance, erratic swimming and quietness Based the outcome of this research and under similar experimental condition it is the recommendation of this research that this pyrethroid will affect the uptake of the major cations and anions. It further advises environmental officers, crop farmers and insecticides habitual users to be cautious on the use of thisinsecticide because of the resultant consequences of the misuse. Keywords: Karate, Uptake, Cations, Anions, Gills, Catfish, Toxicity Animal Research International Vol. 4 (1) 2007 pp. 591-59

Chemistry variation during purging Of alluvial wells At Los Alamos National Laboratory

The purpose of this study is to determine how chemistry results vary from shallow alluvial wells during purging. We sampled seven shallow alluvial wells at four different purge volumes. Drawdown and the field parameters pH, DO, EC, ORP, and turbidity were collected to determine stabilization trends for each well. During each sampling event, water samples were collected after purging one-half, one, two, and three well bores, and later analyzed for metals (unfiltered), and major cations and anions (filtered). Drawdown and turbidity were the only field parameters measured that affected the results. LAO-0.7, MCO-5, MCO-7, and CDBO-6 each had drawdown in excess of 0.3 ft, which, in these cases, seemed either to increase turbidity readings or prevent stabilization. For five of the seven wells, chemistry analyses show the only consistent changes between samples were in Al and Fe, which followed changes in turbidity. The two exceptions were MCO-5 and CDBO-6, which had more drawdown. The major cations and anions showed little variation during purging. For the field parameters, pH and EC showed no change, while temperature, DO, and ORP were not representative of the formation water. In the end, this study suggests drawdown has the main effect on turbidity and turbidity has the main effect on sample quality. Therefore, when drawdown is minimal (around 0.3 ft), or in some cases a little more, and turbidity has stabilized, a representative sample may be collected after purging only one well bore. Otherwise, sample collection might require purging three well bores

Hydrogeological investigations of the Palmerston North region : a thesis presented in partial fulfilment of the requirements for the degree of Masters of Science with Honours in Earth Science at Massey University

The Lower Manawatu River Valley and its major tributary the Pohangina River Valley are incised within the marine strata of the South Wanganui Basin. Lining each valley are a flight of both aggradational and degradational terraces. Three aggradational terraces are identified and correlated with the Ohakea, Rata, and Porewa terraces of the Rangitikei River Valley which aggraded during stadial periods of the Last (Otiran) Glaciation. The distribution of these terraces in the Lower Manawatu River Valley is discussed and their cover beds described. Previous river channels of the Manawatu River are identified by means of bore-log information. The nature and history of the Manawatu River has resulted in a sequence of clay, silt, sand, and gravel deposits which is exceedingly complex in detail. Cross-sections are presented which show this complexity. This has been the main factor influencing the distribution and nature of the aquifers in the region. Water is normally extracted from the coarsest deposits with 75% of the bores in the region obtaining water from gravel layers, 15% from sand layers, and 10% from sand/gravel mixtures. The aquifer system is considered to be "leaky" due to the complex arrangement of lithologies allowing water to flow both vertically and horizontally without much impedance. Depth ranges of 0-60 m, 60-120 m, and > 120 m below the ground surface are considered to be the closest resemblance to separate aquifers. Piezometric contour maps are presented which show an overall groundwater flow direction for all the depth ranges from east to west along the Manawatu River Valley with additional water influx from the Pohangina and Oroua River catchments. Transmisivities of the aquifer system ranges between 150-2000 m2/day and storativity between 1.1 × 19-4 and 3.2 × 10-4. Static water levels and discharge rates increase with depth and decrease from east to west. Nearly all the bores in the area are naturally flowing artesian, making the entire area a discharge zone. Recharge of the aquifer system is from two sources. Firstly, direct percolation of atmospheric precipitation, the main source areas being the Tararua Range, the Ruahine Range, and both the eastern and western flanks of the Pohangina Anticline, and secondly, river recharge. There is a significant loss (6,500 1/s) of water as the Manawatu River flows through the Manawatu Gorge which is identified as occurring in the vicinity of White Horse Rapids. This water loss is attributed to groundwater river recharge of shallow aquifers. Groundwater accounts for nearly 90% of total water use within this area and the estimated water extraction from the aquifer system is 120,000 m3/day (43 × 106 m3/year.) The hydrochemistry of the area is presented by way of isoconcentration contour maps. Total alkalinity, calcium, magnesium, chloride, electrical conductivity, potassium, manganese, sodium, and total dissolved solids increase from east to west within the research area. Free carbon dioxide, fluorine, and iron show no trend but have local "highs". Only sulphate shows an increase from west to east. The average concentrations for the various chemical parameters are: total alkalinity - 157 ppm, Ca - 104 ppm, Cl - 36 ppm, free CO2 - 11 ppm, conductivity - 43 mS/m, F - 0.16 ppm, Fe-2.1 ppm, Fe-2.1 ppm, Mg - 55 ppm, Mn - 0.38 ppm, nitrate - 0.02 ppm, Na - 23 ppm, SO42- - 10 ppm, and total dissolved solids - 256 ppm. Concentrations increase with depth for all the chemical parameters. Conductivity diagrams are presented which show extremely good linear relationships when plotted against all the major cations and anions. These diagrams have practical significance because conductivity is easy to measure in the field

Advisory report on nutrient levels and related ecology of Malham Tarn

Aspects of reported nutrient levels and their ecological implications for Malham Tarn are discussed. Discussion centres upon the data given here as appendices, involving possible evidence of a long-term increase in the concentrations of some nutrients (especially nitrate) of significance for the Tarn's ecology and conservation. Further comparative tests of some methods of chemical analysis employed in obtaining those data are reported

Fast electrophoresis in conventional capillaries by employing a rapid injection device and contactless conductivity detection

A purpose-made set-up featuring an automated fast injector allowed the easy optimization of the injected amount and the adjustment of the separation length of conventional capillaries from a minimum of 5cm upward. It was found that a compromise in capillary length for separation efficiency and analysis time also has to take into account the injected amount, which in turn affects the sensitivity and hence the detection limit. The versatility of the system was demonstrated by the analysis of the major cations and anions in natural water samples in less than 1min, the concurrent determination of a mixture of amino acids and carbohydrates in 160s, and of three active ingredients in a pharmaceutical preparation in 40s. Plate numbers were typically around 50,000 and detection limits down to 1μM could be achieve

Assessing groundwater stoichiometric composition and its suitability in northwestern Bangladesh

Groundwater quality analyses included pH, EC, cations (Ca2+, Mg2+, Na+, K+, Zn2+, Cu2+, Mn2+, Fe3+ and As3+), anions (CO32-, HCO3-, NO3-, SO42-, PO43- and Cl-) and TDS of northwestern Bangladesh. The samples contained Ca2+, Mg2+ and Na+ as the dominant cations and HCO3- and Cl- were the dominant anions. Ratios of major cations and anions of water samples suggest the predominance of Ca and Mg-containing minerals over Na-containing minerals. According to TDS and SAR values, all samples were classed as 'freshwater' and 'excellent' categories. The SSP of all waters was under 'excellent' and 'good' classes. All samples were within 'soft' class regarding hardness with 'suitable' RSC. Based on As3+, Zn2+, Mn2+, Fe3+, SO42-, NO3- and Cl- all groundwater samples were within the 'safe' limit for drinking but unsuitable for some industries for specific ions

Natural and Anthropogenic Sources of Groundwater Salinization in Parts of Karachi, Pakistan

This study is aimed to evaluate the groundwater quality of Gulshan-e-Iqbal and Liaquatabad towns inKarachi. Thirty (n=30) groundwater samples were randomly collected from different locations by electrically pumpedwells at various depths (14-91m). All the water samples were analyzed to determine their suitability for drinkingpurpose based on various physicochemical parameters. Data reveal that high concentration of TDS and hardness havedeteriorated the groundwater quality of study area. The main phenomenon responsible for groundwater pollution is theseawater intrusion due to the proximity of study area to the Arabian sea. Large scale unplanned urbanization, poorwaste management and other anthropogenic activities have also triggered the deterioration of groundwater quality.Study showed that local geology plays vital role in the distribution of major cations and anions. Data suggested thatground water of this study area is highly contaminated by seawater intrusion and considered not fit for drinkingpurpose

Analysis of Precipitates and Waters Associated with an Alkaline Leachate, Gulf State Steel Property, Gadsden, Alabama: A Reconnaissance Study

Calcite stalactites ranging in length from several inches to a foot long are found forming on the southeastern slag pile at the former Gadsden Steel Mill of the Gulf States Steel Corporation. Analyses of samples collected per EISOPQAM guidelines include the following: petrographic, conductivity, pH, XRD, XRF, TDS, and major cations and anions. Preliminary field pH and conductivity measurements indicate that waters near the slag pile have a pH ranging from 11-12 and a conductivity ranging from 1115-6300 μS/ cm. Titration data indicate that the maximum pH value is 12.5. These calcite stalactites and stream coatings result from the dissolution of the steelmaking slag by rainfall. These alkaline waters precipitate calcite when they are in contact with atmospheric CO2. Improper management of slag products can lead to aesthetically impacted environments and ecosystems. Several studies and this study show that steel slag could be used to sequester atmospheric CO2

Change in groundwater chemistry as a consequence of suppression of floods: the case of the Rhine floodplain

Spatio-temporal variations of nitrogen, phosphorus and base cation concentrations in groundwater were related to the drastic change in hydrological conditions of the Rhine alluvial floodplain (Eastern France), which has been disconnected from the river by canalisation. The Groundwater chemistry was studied in two alluvial forests with contrasting hydrological conditions: one in a sector unflooded for 30 years, the second one in a sector still subject to flooding. Nutrient concentrations were measured at two levels, in the root zone (1.5 m depth) and in the gravel below the root layer (4.5 m depth). In the unflooded sector, the average nitrate concentration was significantly lower in the shallow groundwater (2.06 mg l−1 NO3−) than in the deeper layer (5.84 mg l−1NO3−). In contrast, in the flooded sector the nitrate concentrations in the shallow groundwater (5.02 mg l−1 NO3−) were not significantly different from those in the deep groundwater (3.98 mg l−1 NO3−). The concentration of phosphate was similar in shallow and deep groundwater in the unflooded sector (46 and 35 μg l−1, respectively) but significantly lower in the deep groundwater of the flooded sector (47 μg l−1), than in the shallow groundwater (58 μg l−1). The major elements (cations: Ca2+, Mg2+, Na+ and associated anions: HCO3−, SO4−2, Cl−) concentrations were significantly higher in the groundwaters than in the surface water. The results are discussed in terms of changes that accompanied suppression of floods, and processes that take place during the transfer of nutrients through the groundwater–soil–plant compartments. The reduction of groundwater fluctuations in the unflooded sector modified the transfer of nitrate by reducing the resolubilisation of locally produced nitrate, and/or denitrification. The transfer of phosphate was affected to a lesser extent, because of precipitation and adsorption. Base cation concentrations reflect exchange between groundwater and the calcareous gravel