Suitability Assessment of Deep Groundwater for Drinking and Irrigation Use in the Parts of Hoskote and Malur Taluks, Karnataka (India)

Groundwater samples from thirty four bore wells used for drinking and irrigation in parts of Hoskote and Malur taluks, Karnataka State (India), were collected and geochemically analysed during December 2014. The hydrochemical characteristics was dominated by Ca2+-Mg2+ -Cl--SO42- (58.82%) and Ca2+-Mg2+-HCO3- (38.24%), with alkaline earth (Ca+Mg) exceeding alkalies (Na+K) and strong acidic anions dominating weak acidic anions. Weathering of rock-forming minerals regulated chemistry of the groundwater in the study area as indicated by Gibbs plot. The groundwater chemistry in the study area is influenced by silicate dissolution of host rock with contribution from weathering of carbonate rocks while positive CAI values indicated exchange of Na and K from the water with Mg and Ca of the rocks in the study area. The Ca2+/Mg2+ molar ratio plot further supported the fact that dissolution of calcite with effect of silicate minerals contributes calcium and magnesium to 97.06% of the groundwater. SAR, percent sodium, WQI and permeability index values demonstrated the suitability of a majority of the samples for irrigation.DOI: http://dx.doi.org/10.5755/j01.erem.71.1.9809</p

A comparative study on usage of Durov and Piper diagrams to interpret hydrochemical processes in groundwater from SRLIS river basin, Karnataka, India

In the present study, an attempt was made to evaluate and identify hydrogeochem. of water and the involved chem. processes using Durov and Piper diagrams. The prominent hydrochem. facies was Ca2+-​Mg2+-​Cl-​-​SO42-​ in both methods although slight variation in terms of Ca2+-​Mg2+-​HCO3-​ was also obsd. in few water samples. Piper diagrams indicated the dominance of mixed water type (70.84​%) having no one cation-​anion pair exceeds 50​%, while Durov specified the dominance of simple dissoln. or mixing (83.34 %) with no dominant major anion or cation. Thus, both the diagrams signify nonidentification of the water types with neither anions dominant nor cations dominant. Piper diagram, Durov plot and chloroalkaline indexes indicated the dominance of alk. earth elements were over alkalies in majority of samples due to direct exchange of Ca2+ and Mg2+ from the Aquifer matrix with Na+ and K+ from the groundwater. Further, SAR (0.41>SAR %Na WQI < 112.99) values recommended the suitability of 100, 91.67 and 62.5​% of samples for domestic and irrigation purposes

Air Quality Indices to Understand the Ambient Air Quality in Vicinity of Dam Sites of Different Irrigation Projects in Karnataka State, India

Ambient air quality monitoring was carried out in the vicinity of dam and nearby residential sites in four river basins in Karnataka with reference to SPM, RSPM, SO2 and NOx, employing Envirotech APM-460 Respirable Dust Sampler with provision to keep impingers having absorbing reagent. Further, three different methods of Air quality index (AQI) calculation on based on SPM and RSPM values were used to evaluate the prevailed ambient air quality in the near and surroundings areas at the time of dam constructional activities. The concentrations of SPM, RSPM, SO2 and NOx near the dam sites were respectively 540, 170, 5.8 and 17.9 .g/m3 in Varahi river basin; 440, 158, 3.8 and 11.4 .g/m3 in SLIS river basin and, 255.55, 83.3, 2.0 and 1.7.g/m3 in SRLIS river basin. The SPM, RSPM and SO2 concentrations was 340, 70 and 0.3 .g/m3 in the vicinity of dam site of Bellary nala river basin while NOx concentration was below the detectable limit. AQI calculations revealed that the dam sites in all four river basins were high to severely pollute compared to other monitored stations, owing to its construction activitie

Physico-Chemical and Bacteriological Investigation on the River Cauvery of Kollegal Stretch in Karnataka

Cauvery River is the major river system of south India was studied for 19 prime physicochemical and 2 bacteriological parameters at six locations of the Kollegal stretch, for a period of Two years (2006–2008) at monthly intervals. Over the years of time, river has been subjected to human interference regularly and water quality was to be getting deteriorated profoundly. Major anthropogenic activities practiced in and around the stretch: agriculture, abstraction of water for irrigation and drinking, washing cloths and utensils, discharging of sewage waste, sand dredging, boating, fishing, open defecation and religious ritual activities along the stretch were generating serious threat to the biota of the river by altering the physicochemical and biological concentration of the river system. The seasonal and yearly trends were discussed to comprehend anthropogenic interferences on the river stretch. Correlation analysis was also been tried in between physico-chemical parameters. The pH, Conductance, Alkalinity and Hardness levels indicate the moderate quality of water. The values of DO, BOD and COD levels indicate the absence of major organic pollution sources. Seasonal and yearly averages of plant nutrients like phosphate, nitrates, potassium and also sulphates at drain out falls and mixing zones, were not showing any significant variation in their concentration indicate no sign of problems like eutrophication, which is generally raise due to agricultural and sewage wastes. The other possibility is that since there are no major industries in the project area, the major source of organic pollutants is only the domestic source. Population density spread over sparsely located villages like Dasanapura and Harle certainly contributes towards total and fecal coliforms as excreta of the villagers due to lack of toilets in their houses. Thus present study concludes that river water was not polluted; all results are within permissible limit when compared with Bureau of Indian Standards (BIS) and National River water quality standards. DOI: 10.3126/kuset.v6i1.3310 Kathmandu University Journal of Science, Engineering and Technology Vol.6(1) 2010, pp50-5

Spatio-Temporal Variation in Radon Concentration in Groundwater with Respect to Rock Types: A Case Study from Chitradurga District, Karnataka

An attempt was made in the present study to delineate how the radon concentrations vary with respect to different geological formations and to evaluate annual effective dose exposure due to ingestion of radon. A total of 60 groundwater samples were collected from layered sequential aquifers in Chitradurga district having major rock types such as Bababudan Group, Charnockite, Chitradurga Group, Closepet granite, migmatites and granodiorite — tonalitic gneisses and Sargur Schist complex during pre-monsoon and post-season of the year 2011. Radon measurement was made using Durridge RAD-7 radon-in-air monitor, connected to RAD H2O accessory with closed loop aeration concept. In the present study, the radon activity ranged from 0 to 186.6 Bq/L and 0 to 150.6 Bq/L during pre- and post-monsoon seasons of the year 2011, with 56.67 % (17 samples) of samples during both the seasons exceeding the EPA's MCL value of 11.1 Bq/L. The annual mean radon activity in the groundwater was higher in the area having Chitradurga rock group formations (78.1 Bq/L) followed by Sargur-Satyamangalam schist complex group (56.8 bq/L), migmatites and granodiorite — tonalitic Gneisses group (56.3 Bq/L), Closepet granite (42.7 Bq/L), Charnonkite (29.1 Bq/L) and Bababudan Group (22.2 Bq/L). It is inferred that radon concentration found to depend on the tectonic structure, geology of the area and on the presence of uranium minerals in these rocks. The annual effective dose resulting from radon in groundwater in the Chitradurga district were significantly lower than UNSCEAR and WHO recommended limit of 1 mSv/y

Measurement of radon activity in soil gas using RAD7 in the Environs of Chitradurga District, Karnataka, India

A 222Rn survey was carried out in order to explore the pattern of geographical and seasonal changes of 222Rn activity in soil-gas at different locations in Chitradurga district of Karnataka State using RAD7 radon detector coupled with special accessories, without dilution by outside air technique. Radon activity in the soil gas varied from 0.5 to 812.9 (mean: 93.78 Bq/m3) and 0.8 to 810.4 Bq/m3 (mean: 92.84 Bq/m3) during pre-and postmonsoon seasons respectively, with an annual mean of 0.65 to 811.65 Bq/m3 (mean: 93.31 Bq/m3). A significant spatial and insignificant temporal variation in soil radon activity has been observed in the study area, which is in the order of Hosadurga taluk (346.56 Bq/m3)> Hiriyur taluk (95.10 Bq/m3)> Challakere taluk (36.45 Bq/m3)> Chitradurga taluk (20.40 Bq/m3)> Holalkere taluk (2.87 Bq/m3). The results showed the radon values in the soil-gas of Chitradurga district are low (< 0.8 kBq/m3) enough to categorize them under low radon risk areas (viz., 10 kBq/m3)

Quantifcation of radon concentration in groundwater around abandoned Gogi uranium mineralized zone, Yadagir district, Karnataka, India

Radon activity concentrations have been measured by analysing a total of 93 bore well water samples, geographically spread over three taluks of Yadagir district. The analysis involved usage of Durridge’s RAD7 radon analyser equipment with RADH2O accessories by closed loop aeration concept. Having geometric mean concentrations of 37.0, 20.75 and 9.98 Bq/L, radon concentration in 5.71, 14.29 and 6.67% groundwater samples from Yadagir (8.88 Bq/L<Rn<160 Bq/L), Shahapur (1.98 Bq/L<Rn<591 Bq/L) and Surpur (0.586 Bq/L<Rn<206 Bq/L) taluks respectively exceeded the alternative maximum contaminant level (AMCL) of the USEPA (148 Bq/L). Nearly 15% of the groundwater samples had radon concentrations higher than WHO reference level of 100 Bq/L. The calculated total annual efective dose in 38.71, 44.09, and 55.92% of the samples respectively for infants, children and adults was not in consistent with WHO recommended dose level of 100 µSv/y

Evaluation of water quality using geochemical modeling in the Bellary Nala Command area, Belgaum district, Karnataka State, India

The present study aimed at assessment of geochemical composition of 25 water samples to evaluate their suitability for drinking and irrigation purposes in the Bellary Nala command area. Geochemical modeling carried out using PHREEQC program confirmed that majority of the samples in the study area were saturated and/or supersaturated with respect to anhydrite, calcite and gypsum while few were undersaturated with respect to calcite, gypsum, fluorite and halite. From Piper trilinear diagram, Ca2+-Mg2+-HCO 3 - was found to be the dominant water type (~68 ), which could be as a result of dissolution of carbonate minerals such as dolomite and calcite prevailing in the study area. However, cation-exchange processes could be responsible for the formation of the Ca2+-Mg2+-Cl —SO4 2- water type (~32 ) from the CaSO 4 and NaCl types, which in turn formed due to the dissolution of anhydrite, gypsum and halite. Wilcox's and USSL graphical representations showed that majority of the samples belong to good to permissible and high salinity-low sodium (C3S1) category, respectively. Factor analysis concluded that the water quality parameters and saturation indices that are falling under factors 1 and 2 with a strong loading (&gt;75 ) and eigen values (&gt;1) are mainly responsible for controlling the variation in the groundwater chemistry, accounting to 83.3 and 80.72 of total variance, respectively. © 2013 Springer-Verlag Berlin Heidelberg

Geochemistry of groundwater and groundwater prospects evaluation, Anekal Taluk, Bangalore Urban District, Karnataka, India

Anekal Taluk lies in the southern part of the of Bangalore urban district, known for Bannerghatta wildlife sanctuary, Jigani industrial estate, silk industry, and the electronics city, the pride of India and hub of Bangalore's information technology. In the present study, evaluation of geochemistry of 28 representative bore wells samples from Anekal Taluk was undertaken. It was found that most of the samples (92.9) belong to Ca2+-Mg 2+-Cl- SO24- water type with Ca-Mg-Cl and Ca-Cl hydrochemical facies. The groundwater sources were further categorized as normal chloride (32.14) and normal sulfate (100) water types based on Cl and SO4 concentrations. Majority of the samples (64.3) belong to C3-S1 water class, indicating water with high salinity and low sodium. Positive index of base exchange indicates the chloro-alkaline equilibrium in the study area. Groundwater potential zonation map for Anekal Taluk was generated using multiparametric and weighted overlay method using the spatial analyst tool in ArcGIS v9.2. Accordingly, five distinct classes corresponding to good(high), moderate (medium), moderate to poor (low), poor (very low), and poor to nil (very low) groundwater potential zones were identified in the region. Of this, 85.27 of the study area belongs to good/high to moderate/medium groundwater potential and only 14.73 belonging to moderate/poor to nil groundwater potential zones. © 2010 Springer Science+Business Media B.V

Temporal Variation in Indoor Air and Soil-Gas Radon Concentrations

Airborne indoor radon activity ranged from 0.0 to 67.10 Bq/m3 with an average value of 20.71 Bq/m3 over a period of 48 hours, which was very less compared to the respective action level values of 148 and 100 Bq/m3 prescribed by EPA (1991) and WHO (2009). The radon progeny (PAEC) concentration varied from 0.0 to 7.25 mWL (average: 2.24 ± 2.11 mWL) while their resultant lifetime fatality risk varied from 0.0 x 10−4 to 0.90 x 10−4 (average: 0.28 x 10−4). The study area is categorized as low radon risk area (<10 kBq/m3) as the soil gas radon concentration varied from 7130 to 9590 Bq/m3 (viz., 7.13 to 9.59 KBq/m3)