Assessment of groundwater quality and its suitability for agricultural usage in and around Rangampeta area,Andhra Pradesh,south India

The aim of this study is to assess the groundwater quality of Rangampeta area for irrigation and domestic purposes. The groundwater samples were analyzed for distribution of chemical elements Ca, Mg, Na, K, Si, HCO₃, CO₃, Cl and SO₄. It also includes pH, electrical conductivity, total hardness, non carbonate hardness and total alkalinity. The parameters like sodium absorption ratio, adjusted sodium absorption ratio, sodium percentage, potential salinity, permeability index and residual sodium carbonate were calculated. The dominant hydrochemical facies of groundwater are Ca–Mg–Cl and Na–Cl Water Types. The Gibbs’s diagram plots suggest that the chemical weathering of rock forming minerals is the major driving force controlling water chemistry in this area. The positive chloro-alkaline indices revealed that the groundwater has suffered ion exchange between Na and K of water with Ca and Mg of soil during its flow.     

Integrative quantification and balancing of contaminant fluxes in urban groundwater, case study Darmstadt

The qualitative and quantitative impact of a city on groundwater is presented in the case study of Darmstadt. The impact of land use on groundwater quality in Darmstadt is higher than the impact of background geological processes. The occurrence of Cl, B and Fe is only influenced by land use, while EC, HCO₃ and PO₄ are controlled by geology and land use. An integrative, spatially differentiating quantification of mass fluxes shows that e. g. Cl and B are introduced from urban sources such as leaking sewers and road salting. Input is highest under industrial areas (Cl 317 mg/d?·?m², B 0,6 mg/d?·?m²). For N_tot agricultural input (114 mg/d?·?m²) is more important than urban input with a maximum of 14 mg/d?·?m². Comparing overall urban input with estimated urban input, it can be concluded that there are additional sources for HCO₃, Ca, Mg, SO₄, Na, Cl, B and NO₃, which are not included in the estimated input (e. g. geogenic sources, fill material, industrial sources & degradation processes). PO₄ and N_tot on the other hand are being degraded and COD is consumed. A decrease of concentrations downstream from the city can be ascribed to diving plumes.     

Effect of ash disposal ponds on groundwater quality at a coal-fired power plant

The impact of fly and bottom ash disposal ponds on groundwater quality was investigated at the coal-fired Columbia Power Plant at Portage, Wis. Groundwater sampling was conducted utilizing a network of piezometers and multilevel wells located at various cross-sections of the ash disposal facility. Analyses were performed for 16 major and minor elements, pH and conductivity. Data for a 3-yr monitoring program established the existence of large B, Na and SO₄ plumes in the groundwater system surrounding the ash disposal area. Substantial amounts of B, Na and SO₄ were present in the plume and portions were discharged into an adjacent wetland as the plumes moved with groundwater flow. The secondary fly ash settling pond was the major source of B and SO₄, while the main source of Na was from previous releases to the aquifer from the use of Na₂CO₃ to condition fly ash to enhance removal of SO₂ from flue gas by electrostatic precipitation. Movement into the groundwater of heavy metals such as Cu and Zn was not observed and their concentrations are likely attenuated in the pond.     

Combined biological treatment of high‐sulphate wastewater from yeast production

The wastewater from baker's yeast production contains above‐average concentrations of organic pollutants (25 000 mg/L total chemical oxygen demand, TCOD), nutrients (1500 mg/L N_tot, 100 mg/L P_tot) and sulphate (2900 mg/L SO₄^2?). Baker's yeast wastewater with a flow rate of 190 m³/day was treated in a mesophilic anaerobic/anoxic continuous stirred tank reactor (CSTR) system. At the expense of the reduction of trimethylglycine (or betaine‐component of sugar‐beet molasses) to other nitrogen‐containing compounds, it was possible to re‐oxidize the sulphides to elemental sulphur, remove them from the wastewater and increase biogas production. Therefore, the average removal efficiency in the anaerobic/anoxic system was 79% by TCOD, 100% by SO₄^2? in which the concentration of sulphides in the effluent did not exceed 50 mg/L. The application of this combined anaerobic/anoxic system to a full‐scale treatment plant supported biogas production up to 1300 m³/day, and the purification of wastewater was feasible without the use of granular sludge.     

The changes of bamboo pulping waste water residuals in biological treatment process

The residuals of the bamboo pulping wastewater were analysed systematically. The COD (chemical oxygen demand) decreased significantly by adding appropriate coagulant (1.5 kg/m³ 10% Al₂ (SO₄)₃ as coagulant and 2 mg/L anionic PAM as coagulant aid) to the effluent in secondary sedimentation tank. The study found that hydrolytic bacteria in primary sedimentation tank and balancing tank may increase the ratio of BOD/COD and promote the release of ammonia nitrogen (NH₃‐N), which was benefit to further degradation of organic pollutants by aerobic biological treatment. Through optimizing biochemical process and adjusting contents of nitrogen, phosphorus, and mineral elements, the effects of wastewater treatment has been greatly enhanced and the quality of discharged water could met the new national standard GB3544‐2008.     

Effects of acid mine drainage on groundwater quality: a case study from an open-pit copper mine in eastern Turkey

This study was undertaken to determine the variation in groundwater quality of an open-pit copper mine in Maden (eastern Turkey) which has been in operation since 2000 BC, and with modern methods since 1939. Physical and chemical parameters (including pH, temperature, electrical conductivity, concentrations of Na, K, Ca, Mg, Cl, HCO₃, SO₄, NO₃, Fe, Co, Cr, Mn, Ni, Cu, Zn, Al, Cd, and Pb) of the groundwater and spring water samples from the study area were measured on a seasonal basis between October 2009 and July 2010. The groundwater quality was hydrochemically assessed in order to determine its suitability for human consumption and agricultural use. The measured and analyzed parameters in all the water samples were below the maximum admissible concentrations set out in international and national standards, guidelines, directives, and regulations for human consumption and for agricultural purposes. In addition, the results of previous studies on the possible effects of the mine site on soil, stream sediment, plants, and surface water in the same area are discussed.     

Variation in rainwater chemistry,and its relation to synoptic conditions,at a site in North‐West England

Detailed studies of the chemistry of rainwater from 28 storms have been made at a site near Lancaster, England, using a specially‐designed sampler. Major cations and anions show high concentrations in the first rainfall collected for each event, and rapidly decrease to low but finite values in later samples. High initial concentrations are attributed to dissolution of aerosols and dry deposits previously collected on the funnel. The total ionic contribution to the rainwater samples by this process can be related linearly to the length of the dry period preceding the storm. Comparison of rainwater chemistry and storm trajectories suggests that airmasses which have passed over industrial areas have rainwater chemistry (high SO₄, Ca; low Na, Cl) which is distinct from that associated with storms of marine origin (high Na, Cl; low SO₄).     

Estimation of environmental impacts on the water quality of Incesu-Dokuzpınar Springs in Kayseri,Turkey

Industrial and agricultural activities have directly or indirectly affected the concentrations of a large number of inorganic chemicals in groundwater, for example NO₃, N₂, Cl, SO₄, H⁺, K, Mg, Ca, Fe, Cu, B, Pb and Zn, as well as a wide variety of pesticides and other organic compounds. For reactive contaminants like NO₃, it is recommended that a combination of hydrochemical and environmental-tracer analytical approaches might be required to resolve changing inputs from subsequent alterations as causes of concentration gradients in groundwater. The water type of ncesu-Dokuzpnar Springs is mainly Na–Mg–Ca–Cl–HCO₃. Note that the water types of the Springs were directly related to the hydrogeochemical properties of outcrops at the study area. Thus, the high concentration of Ca⁺² and HCO₃ is mainly related to the high CO₂ contents in the marbles, whereas the high Na concentration arises from the existing syenite, volcanic ash, basalt and clay units, although the ncesu-Dokuzpnar Springs cover most of the drinking and irrigation water demands at the study area. Therefore, relevant hydrogeochemical and statistical studies were carried out for estimating the mentioned environmental impacts on the water quality of ncesu-Dokuzpnar Springs.     

Long-term water quality monitoring of the Sejnane reservoir in northeast Tunisia

The Sejnane reservoir in northeast Tunisia provides drinking and irrigation water. Long-term water quality monitoring data including precipitation, evaporation, temperature, pH, conductivity, dissolved oxygen, turbidity, total suspended solids, major anions and cations, fluoride, BOD₅, NO₃ ⁻, NO₂ ⁻, NH₄ ⁺, P _tot, fecal coliform bacteria, boron and heavy metals (Fe, Zn, Cu, Ni, Pb, Cr and Cd) are reported. The appropriateness for irrigation was estimated by the SAR and Na percentage and the water quality assessed using the Canadian Water Quality Index as good to excellent, which confirmed its suitability for drinking, aquatic life and irrigation purposes.      

A voltammetric electronic tongue as tool for water quality monitoring in wastewater treatment plants

The use of a voltammetric electronic tongue as tool for the prediction of concentration levels of certain water quality parameters from influent and effluent wastewater from a Submerged Anaerobic Membrane Bioreactor pilot plant applied to domestic wastewater treatment is proposed here. The electronic tongue consists of a set of noble (Au, Pt, Rh, Ir, and Ag) and non-noble (Ni, Co and Cu) electrodes that were housed inside a stainless steel cylinder which was used as the body of the electronic tongue system. As a previous step an electrochemical study of the response of the ions sulphate, orthophosphate, acetate, bicarbonate and ammonium was carried out in water using the electrodes contained in the electronic tongue. The second part of the work was devoted to the application of the electronic tongue to the characterization of the influent and effluent waters from the wastewater treatment plant. Partial Least Squares analysis was used to obtain a correlation between the data from the tongue and the pollution parameters measured in the laboratory such as soluble chemical oxygen demand (CODs), soluble biological oxygen demand (BODs), ammonia (NH₄-N), orthophosphate (PO₄-P), Sulphate (SO₄-S), acetic acid (HAC) and alkalinity (Alk). A total of 28 and 11 samples were used in the training and the validation steps, respectively, for both influent and effluent water samples. The electronic tongue showed relatively good predictive power for the determination of BOD, COD, NH₄-N, PO₄-P, SO₄-S, and Alk.     

Rate constants of reactions of ozone with organic and inorganic compounds in water—III. Inorganic compounds and radicals

Second-order rate constants for reactions of ozone with 40 inorganic aqueous solutes are reported. Included are compounds of sulfur (e.g. H₂S, H₂SO₃, HOCH₂SO₃H), chlorine (e.g. Cl⁻, HOCl, NH₂Cl, HClO₂, ClO₂), bromine (e.g. Br⁻, HOBr), nitrogen (e.g. NH₃, NH₂OH, N₂O, HNO₂) and oxygen (e.g. H₂O₂), as well as free radicals (e.g. O₂⁻, OH^•). Most of these compounds exhibit an increase in rate constant with increasing pH corresponding to their degree of dissociation. Rate constants are based on ozone consumption rates measured by conventional batch-type or continuous-flow methods (10⁻³-10⁺⁶ M⁻¹ s⁻¹ range) and determinations of stoichiometric factors. Also listed are data determined by pulse-irradiation techniques using kinetic spectroscopy (10¹⁰ M⁻¹ s⁻¹ range). Additional literature data are reviewed for completeness. Results are discussed with respect to water treatment and environmental processes.     

Lecane tenuiseta rotifers improves activated sludge settleability in laboratory scale SBR system at 13°C and 20°C

Two experiments at different temperatures were conducted in five laboratory‐scale bioreactors with enhanced nutrient removal simulating the work of sequencing batch reactors (SBRs). The process was operated in three 8‐hour cycles. The oxygen concentration, pH and temperature were controlled and maintained at 1 mg of O₂/L, 7 and 13°C, respectively, throughout the first two weeks and at 20°C for the next 10 days. The introduction of Lecane tenuiseta improved the settling properties of the activated sludge dominated by Microthrix parvicella at both temperatures tested. L. tenuiseta rotifers led to a reduction in filamentous bacteria abundance and did not negatively affect the chemical parameters of the effluent. For each temperature, there were no differences in COD, N_tot, N‐NH₄ or P‐PO₄ values between the treatment and control bioreactors. The results have shown that the application of L. tenuiseta is a promising biological tool for bulking prevention especially in a cold season.     

Hydrogeological and Hydrochemical Study of the Al-Shagaya Field-F, Kuwait

The study area, Al-Shagaya Field-F, is located at the south western part of Kuwait and includes twenty-seven production water wells, tapping the Kuwait Group aquifer. The main objectives of this study were to identify the aquifer type, determine its properties, outline the geological factors and the hydrochemical processes that control the quality of the groundwater of the study area, and to assess the water quality of the Kuwait Group aquifer. Analyses of aquifer test data revealed that the Kuwait Group aquifer acts as a semi-confined to confined aquifer, with a range of transmissivity values between 103 and 1,198 m²/day. The initial water level ranges from 70 to 146 m (M.S.L). The estimated quantity of groundwater entering the study area is about 12,950 m³/day. The chemical analyses show that the groundwater of the study area is a brackish water type, with total dissolved solids ranging from 3,586 to 5,334 mg/l. The aquifer salinity increases in the direction of regional flow towards the NE. The average pH value is 7.7 and the average electrical conductivity is 5,349 s/cm. Groundwater is highly concentrated with Na⁺, Ca²⁺, Cl^- and SO₄^2- and is depleted in HCO₃^- and Mg²⁺ ions. It is characterized by secondary salinity, where the alkaline earths exceed the alkalies and strong acids exceed weak acids. Three groundwater chemical types are recognized: NaCl, Na₂SO₄ and CaCl₂. The NaCl water type is the most abundant in the study area. The main genetic types of water are: MgCl₂ and Na₂SO₄. It is found that the groundwater is oversaturated with respect to aragonite and calcite and undersaturated with respect to anhydrite, gypsum, halite and dolomite. A comparison of the hydrochemical coefficients of Na⁺/Cl^-, SO₄^2-/Cl^- and Ca²⁺/Mg²⁺ in the study area with those of seawater and river water shows that the groundwater of the study area is a mixture of marine and continental water.     

Nitrogen transformations in a simulated overland flow wastewater treatment system

Overland flow treatment of municipal and industrial wastewater has been proposed as an economical and effective method of removing pollutants. Properly designed and manipulated nitrification-denitrification in this technique could remove a significant amount of N.Applications of wastewater containing NH₄⁻ −N to a simulated overland flow model led to the disappearance of NH₄⁺ −N and the formation of nitrate. The N balance in simulated overland flow system was estimated by using labeled ¹⁵N. The amount of N removed in the system depends upon denitrification rates. The results of this study indicated N was absorbed by soil and applied NH₄⁺ −N was assimilated by the vegetation. The absorbed NH₄⁺ −N on the aerated surface soil mass was nitrified and converted to oxidized forms of N. The nitrate formed diffused downward to the reduced zone during subsequent wastewater applications. Some of this nitrate was denitrified to gaseous forms of N or was reduced to organic forms by assimilatory processes. Thus, the net loss of N in an overland flow system was less than would have been predicted from non-labeled N mass balance calculations.     

Groundwater quality assessment of Dhanbad district, Jharkhand, India

Groundwater quality assessment is important to ensure sustainable safe use of water. However describing the overall water quality in the Dhanbad coal mining area of India is difficult due to the spatial variability of multiple contaminants and wide range of indicators that could be measured. An attempt has been made to study the spatial variation of groundwater quality based on an integrated analysis of physico-chemical parameters and use of Geographic Information System (GIS). Using GIS contouring methods with Arcview 3.2a, spatial distribution maps of Hardness, pH, TDS, HCO₃, SO₄, NO₃, Ca, Mg, Cl, and F have been created. From the Water Quality Index map it is inferred that despite the mining and heavy industry, the quality of water is predominantly good to excellent.     

Chemical composition of precipitation in tropical marine atmosphere around Indian subcontinent

Precipitation samples collected on board Indian Naval ships over the oceans surrounding peninsular India during MONEX-79 experimental programme of GARP, were assayed for Na, Cl, Mg, Ca, K, Sb, Th, Fe, Zn, Sc, Cr, Co and SO₄ concentrations. The Na/Cl and Mg/Cl distribution is observed to be in the same ratio as that found in sea water. SO₄/Na ratio in rain water also lies very close to sea water ratio of 0.25, unlike that reported for marine aerosols. K and Ca levels indicate an enrichment with reference to Na. Samples collected far away from the coast suggest enrichment of Ca in the sea salt aerosol and that from nearer the coast also gave high Ca excesses indicative of its contribution from the land. Major source of Fe and Sc appears to be of soil origin, while continental derived elements of anthropogenic origin such as Zn and Sb correlate with Rn concentrations and are useful as tracers for air mass movements.     

Investigating the potential role of ammonia in ion chemistry of fine particulate matter formation for an urban environment

To investigate the potential role of ammonia in ion chemistry of PM_2.5 aerosol, measurements of PM_2.5 (particulate matter having aerodynamic diameter < 2.5 µm) along with its ionic speciation and gaseous pollutants (sulfur dioxide (SO₂), nitrogen oxides (NO_x), ammonia (NH₃) and nitric acid (HNO₃)) were undertaken in two seasons (summer and winter) of 2007-2008 at four sampling sites in Kanpur, an urban-industrial city in the Ganga basin, India. Mean concentrations of water-soluble ions were observed in the following order (i) summer: SO₄²⁻ (26.3 µg m^− 3) > NO₃⁻ (16.8) > NH₄⁺ (15.1) > Ca²⁺ (4.1) > Na⁺ (2.4) > K⁺ (2.1 µg m^− 3) and (ii) winter: SO₄²⁻ (28.9 µg m^− 3) > NO₃⁻ (23.0) > NH₄⁺ (16.4) > Ca²⁺(3.4) > K⁺(3.3) > Na⁺ (3.2 µg m^− 3). The mean molar ratio of NH₄⁺ to SO₄²⁻ was 2.8 ± 0.6 (mostly >2), indicated abundance of NH₃ to neutralize H₂SO₄. The excess of NH₄⁺ was inferred to be associated with NO₃⁻ and Cl⁻. Higher sulfur conversion ratio (F_s: 58%) than nitrogen conversion ratio (F_n: 39%) indicated that SO₄²⁻ was the preferred secondary species to NO₃⁻. The charge balance for the ion chemistry of PM_2.5 revealed that compounds formed from ammonia as precursor are (NH₄)₂SO₄, NH₄NO₃ and NH₄Cl. This study conclusively established that while there are higher contributions of NH₄⁺, SO₄²⁻ to PM_2.5 in summer but for nitrates (in particulate phase), it is the winter season, which is critical because of low temperatures that drives the reaction between ammonia and HNO₃ in forward direction for enhanced nitrate formation. In summary, inorganic secondary aerosol formation accounted for 30% mass of PM_2.5 and any particulate control strategy should include optimal control of primary precursor gases including ammonia.     

Source identification of nitrous oxide on autotrophic partial nitrification in a granular sludge reactor

Emission of nitrous oxide (N₂O) during biological wastewater treatment is of growing concern since N₂O is a major stratospheric ozone-depleting substance and an important greenhouse gas. The emission of N₂O from a lab-scale granular sequencing batch reactor (SBR) for partial nitrification (PN) treating synthetic wastewater without organic carbon was therefore determined in this study, because PN process is known to produce more N₂O than conventional nitrification processes. The average N₂O emission rate from the SBR was 0.32 ± 0.17 mg-N L⁻¹ h⁻¹, corresponding to the average emission of N₂O of 0.8 ± 0.4% of the incoming nitrogen load (1.5 ± 0.8% of the converted NH₄⁺). Analysis of dynamic concentration profiles during one cycle of the SBR operation demonstrated that N₂O concentration in off-gas was the highest just after starting aeration whereas N₂O concentration in effluent was gradually increased in the initial 40 min of the aeration period and was decreased thereafter. Isotopomer analysis was conducted to identify the main N₂O production pathway in the reactor during one cycle. The hydroxylamine (NH₂OH) oxidation pathway accounted for 65% of the total N₂O production in the initial phase during one cycle, whereas contribution of the NO₂⁻ reduction pathway to N₂O production was comparable with that of the NH₂OH oxidation pathway in the latter phase. In addition, spatial distributions of bacteria and their activities in single microbial granules taken from the reactor were determined with microsensors and by in situ hybridization. Partial nitrification occurred mainly in the oxic surface layer of the granules and ammonia-oxidizing bacteria were abundant in this layer. N₂O production was also found mainly in the oxic surface layer. Based on these results, although N₂O was produced mainly via NH₂OH oxidation pathway in the autotrophic partial nitrification reactor, N₂O production mechanisms were complex and could involve multiple N₂O production pathways.     

The risks from airborne asbestos in the urban environment

The objective of this full‐scale study is to determine the treatment performance of the activated sludge process for treating low strength municipal wastewater. The plant is located in Painesville, Ohio, and discharges its treated effluent into Grand River. The average plant wastewater flow was 3.43 MGD (million gallons per day). The plant performance was evaluated for a 12‐month period in 1989. The low strength municipal wastewater contained 104 mg/L TSS (total suspended solids), 105 mg/L BOD (biochemical oxygen demand), 17.76 mg/L TKN (total kjeldahl nitrogen), 9.66 mg/L NH₃‐N, and 3.90 mg/L P (phosphorus). The treatment performance after various degrees of treatment is as follows: primary treatment: 30% BOD and 54% TSS removal, secondary treatment: 97% BOD and 87% TSS removal, and tertiary treatment: 98% BOD and 98% TSS removal. The primary effluent contained 73 mg/L BOD and 48 mg/L TSS; the secondary effluent contained 3 mg/L BOD and 13 mg/L TSS; and the final effluent contained 2 mg/L BOD and 2 mg/L TSS. The effluent contained 0.22 mg/L NH₃‐N and 0.49 mg/L P, which were far below the US EPA standard of 10 mg/L BOD, 10 mg/L TSS, 1 mg/L NH₃‐N, and 1 mg/L P.