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Shrivastava R.,Bhabha Atomic Research Center | Dash S.K.,Indian Institute of Technology Delhi | Oza R.B.,Bhabha Atomic Research Center | Hegde M.N.,Environmental Survey Laboratory
Annals of Nuclear Energy | Year: 2015

In this study, the Weather Research and Forecasting (WRF) model performance with various combinations of parameterization schemes is analyzed in predicting surface and upper air meteorology around the Kaiga nuclear power plant site. The case studies selected for simulation correspond to occurrences of annual maximum, minimum temperature and maximum wind speed in the years (2004-2007). Based on the collective performance of the various combinations of the schemes in reproducing observed winds, temperature and relative humidity at Kaiga site, the most suitable combination of parameterization schemes are identified. For temperature and relative humidity, the combination consisting of Asymmetric Convective Model (ACM2) as the Planetary Boundary Layer (PBL) scheme, the Monin Obhukhov as the surface layer (SL) scheme and the 5 layer thermal diffusion model as the land surface model (LSM) is found to be better than other combinations whereas the combination consisting of Mellor Yamada Janjic (Eta) as the PBL scheme, Monin Obhukhov Janjic (Eta) as the SL scheme and Noah LSM performs reasonably well in reproducing the observed wind conditions. This indicates that the selection of parameterization schemes may depend on the intended application of the model for a given site. © 2014 Elsevier Ltd. All rights reserved.

Patra A.K.,Environmental Survey Laboratory | Wagh S.S.,Environmental Survey Laboratory | Jain A.K.,Environmental Survey Laboratory | Hegde A.G.,Bhabha Atomic Research Center
Environmental Monitoring and Assessment | Year: 2010

Concentration of trace elements such as Fe, Cu, Ni, and Zn were measured in cereals, pulses, vegetables, fish, meat, milk, egg, and water samples collected around Kakrapar, Gujarat, India. A wide variation of the trace element concentration was observed among all the dietary matrices. The concentration of Fe is comparatively more in all the dietary matrices. The concentrations of these elements are translated into intake rates through ingestion pathways. Daily intake (milligrams/day) of Fe, Cu, Ni, and Zn by adult population of Kakrapar, Gujarat were 16.5 ± 6.2, 3.3 ± 1.2, 1.8 ± 1.0, and 3.6 ± 1.3, respectively. Dietary sources of Fe, Cu, and Ni by Kakrapar adult population are comparable with RDA. In case of Zn, the daily dietary intake is comparatively lower than that of RDA. © Springer Science + Business Media B.V. 2009.

Shrivastava R.,Bhabha Atomic Research Center | Dash S.K.,Indian Institute of Technology Delhi | Hegde M.N.,Environmental Survey Laboratory | Pradeepkumar K.S.,Bhabha Atomic Research Center | Sharma D.N.,Bhabha Atomic Research Center
Journal of Environmental Radioactivity | Year: 2014

The TRMM rainfall product 3B42 is compared with rain gauge observations for Kaiga, India on monthly and seasonal time scales. This comparison is carried out for the years 2004-2007 spanning four monsoon seasons. A good correlation is obtained between the two data sets however; magnitude wise, the cumulative precipitation of the satellite product on monthly and seasonal time scales is deficient by almost 33-40% as compared to the rain gauge data. The satellite product is also compared with APHRODITE's Monsoon Asia data set on the same time scales. This comparison indicates a much better agreement since both these data sets represent an average precipitation over the same area. The scavenging coefficients for 131I and 137Cs are estimated using TRMM 3B42, rain gauge and APHRODITE data. The values obtained using TRMM 3B42 rainfall data compare very well with those obtained using rain gauge and APHRODITE data. © 2014 Elsevier Ltd.

Rao D.D.,Environmental Survey Laboratory | Baburajan A.,Environmental Survey Laboratory | Sudheendran V.,Environmental Survey Laboratory | Verma P.C.,Bhabha Atomic Research Center | Hegde A.G.,Bhabha Atomic Research Center
Journal of Environmental Radioactivity | Year: 2010

The evaluation and assessment of monitoring data generated over a period of 1983-2007 (25 years) of a nuclear facility is presented. Time trends of particulate radioactivity, correlation between 137Cs in discharge canal seawater and station discharged activity and correlation of 137Cs, 60Co, and 131I in marine species such as sponge and Nerita (gastropod) and corresponding discharged activity are discussed. The concentration of 137Cs and 131I in seawater versus biota are discussed. A good correlation between 137Cs in seawater and 137Cs in liquid waste discharged was observed (R2 = 0.8, p < 0.001). Similarly, correlation was good for Nerita and discharged concentration of 137Cs, 131I and 60Co (R2 = 0.55-0.73 and p < 0.001). The measurements over the years indicated that there is no accumulation of radionuclides in either the terrestrial or aquatic environments. The mean 137Cs decreased from the pre-operational levels: 7.0-3.6 Bq kg-1 in soil, 0.91-0.016 Bq L-1 in milk and 0.28-0.036 Bq kg-1 in vegetation. Similarly, the mean 90Sr in these matrixes decreased from 3.9 to 0.26 Bq kg-1; 0.37-0.011 Bq L-1 and 0.34-0.022 Bq kg-1 respectively. Cesium-137 of about 700 μBq m-3 was measured in the air filter disks during 1986 and there was a decrease of three orders of magnitude in concentration over the 25 years. The evaluation of environmental data indicated that the radionuclide concentrations and potential impacts, in terms of effective dose to the members of public, have significantly reduced since 1969. © 2010 Elsevier Ltd.

Karunakara N.,Mangalore University | Ujwal P.,Mangalore University | Yashodhara I.,Mangalore University | Rao C.,Mangalore University | And 3 more authors.
Journal of Environmental Radioactivity | Year: 2013

Detailed studies were carried out to establish site-specific soil to grass transfer factors (Fv) and grass to cow milk transfer coefficients (Fm) for radioactive cesium (137Cs) and stable cesium (Cs) for Kaiga region, where a nuclear power station has been in operation for more than 10 years. The study included adopted cows, cows of local farmers, and cows from the dairy farm. A grass field was developed specifically for the study and 2 local breed cows were adopted and allowed to graze in this grass field. The soil and grass samples were collected regularly from this field and analyzed for the concentrations of 137Cs and stable Cs to evaluate the soil to grass Fv values. The milk samples from the adopted cows were analyzed for the 137Cs and stable Cs concentrations to evaluate Fm values. For comparison, studies were also carried out in dominant grazing areas in different villages around the nuclear power plant and the cows of local farmers which graze in these areas were identified and milk samples were collected and analyzed regularly. The geometric mean values of Fv were found to be 1.1×10-1 and 1.8×10-1 for 137Cs and stable Cs, respectively. The Fm of 137Cs had geometric mean values of 1.9×10-2dL-1 and 4.6×10-2dL-1, respectively, for adopted Cows 1 and 2; 1.7×10-2dL-1 for the cows of local farmers, and 4.0×10-3dL-1 for the dairy farm cows. The geometric mean values of Fm for stable Cs were similar to those of 137Cs. The Fm value for the dairy farm cows was an order of magnitude lower than those for local breed cows. The Fm values observed for the local breed cows were also an order of magnitude higher when compared to the many values reported in the literature and in the IAEA publication. Possible reasons for this higher Fm values were identified. The correlation between Fv and Fm values for 137Cs and stable Cs and their dependence on the potassium content (40K and stable K) in the soil and grass were also studied. In order to estimate the ingestion dose accurate data of the dietary habits of the population was necessary and this data was collected through a well planned demographic survey. The internal doses to a child due to the ingestion of 137Cs along with the milk of the local cows and from the dairy farm were found to be 0.29μSvy-1 and 0.04μSvy-1,while that to an adult were 0.39μSvy-1 and 0.05μSvy-1, respectively. © 2013 Elsevier Ltd.

Rao D.D.,Bhabha Atomic Research Center | Sudheendran V.,Environmental Survey Laboratory | Sarkar P.K.,Bhabha Atomic Research Center
Applied Radiation and Isotopes | Year: 2012

Determination of actinides in environmental and biological samples is an important activity of radiation protection program at nuclear energy facilities. High resolution alpha spectrometry with passivated ion implanted Silicon detectors is widely used for the determination of actinides concentration. Low levels of activity concentrations in these samples often require long counting duration of a few days to obtain accurate and statistically significant data for further impact assessment. In alpha spectrometry, the chamber in which Si detector operated is a critical component and maintained at a desired vacuum for minimizing the alpha particle attenuation. Experimental evaluation of variations in energy resolution and tailing of alpha spectra was investigated under different chamber air pressures from about 6.7. Pa to more than 2700. Pa under the chamber hold mode and pump electrically switched off conditions. As part of validation, data collected on an IAEA inter-comparison exercise sample are presented under short and long counting durations with pump operating and switched off conditions respectively. It has been observed that the FWHM values do not significantly degrade, to impact the low and medium level concentration alpha spectra, for variations in vacuum chamber pressures from about 6.7. Pa to 2700. Pa. © 2012 Elsevier Ltd.

Senthilkumar B.,Anna University | Dhavamani V.,AVVM Sri Pushpam College | Ramkumar S.,Environmental Survey Laboratory | Philominathan P.,AVVM Sri Pushpam College
Journal of Medical Physics | Year: 2010

This study assesses the level of terrestrial gamma radiation and associated dose rates from the naturally occurring radionuclides 232 Th, 238 U and 40 K in 10 soil samples collected from Thanjavur (Tamil Nadu, India) using γ-ray spectrometry. The activity profile of radionuclides has clearly showed the existence of low level activity in Thanjavur. The geometric mean activity concentrations of 232 Th, 238 U and 40 K is 42.9±9.4 Bq.kg-1 , 14.7±1.7 Bq.kg-1 and 149.5±3.1 Bq.kg-1 respectively are derived from all the soil samples studied. The activity concentration of 232 Th, 238 U and 40 K in soil is due to the presence of metamorphic rocks like shale, hornblende-biotite gneiss and quartzofeldspathic gneiss in these areas. Gamma absorbed dose rates in air outdoors were calculated to be in the range between 32 nGy.h-1 and 59.1 nGy.h-1 with an arithmetic mean of 43.3± 9 nGy.h-1. This value is lesser than the population weighted world-averaged of 60 nGy.h-1. Inhabitants of Thanjavur are subjected to external gamma radiation exposure (effective dose) ranging between 39.2 and 72.6 μSv.y-1 with an arithmetic mean of 53.1±11 μSv.y-1. The values of the external hazard index determined from the soil radioactivity of the study area are less than the recommended safe levels.

Sowmya M.,Anna University | Senthilkumar B.,Anna University | Seshan B.R.R.,Anna University | Hariharan G.,Anna University | And 3 more authors.
Radiation Protection Dosimetry | Year: 2010

The activity concentration of naturally occurring radioactive elements such as 226Ra, 232Th and 40K were measured for 46 soil samples collected in the vicinity of the Madras atomic power station, Kalpakkam, South India using gamma-ray spectroscopy. The average activity concentration of 226Ra, 232Th and 40K in soil samples were found to be 22.6±12.6, 92.8±44.3 and 434.1±131.1 Bq kg-1, respectively. The activity concentration of natural radionuclides is higher than the world average except for 226Ra. The external absorbed gamma dose rates due to 226Ra, 232Th and 40K are observed to be 74.6±30.8 nGy h-1 with a corresponding annual effective dose of 91.5±37.8 μSv y-1, which are also above the world average. The values of radium equivalent activity and external hazard index are less than the world average. Whereas, the values of the radioactivity level index (Iγ) and the total gamma dose rate were found to be above the required criterion. © The Author 2010. Published by Oxford University Press. All rights reserved.

Ross E.M.,Scott Christian College Autonomous | Raj Y.L.,Scott Christian College Autonomous | Wesley S.G.,Scott Christian College Autonomous | Rajan M.P.,Environmental Survey Laboratory
Journal of Environmental Radioactivity | Year: 2013

The activity concentrations of certain radionuclides were quantified in some plant foods cultivated around Kudankulam, where a mega-nuclear power plant is being established. The activity concentrations were found more in the 'pulses' group and were the lowest in 'other vegetable' category. The annual effective dose was computed based on the activity concentration of radionuclides and it was found to be higher due to the consumption of cereals and pulses. Other vegetables, cereals, pulses and nuts recorded high transfer factors for the radionuclide 228Ra. Fruits, leafy vegetables, tubers and roots, and palm embryo registered high transfer factors for 226Ra. Group-wise activity concentration, radiation dose to the public and soil-plant-to-transfer factor are discussed in detail. © 2012 Elsevier Ltd.

Singh M.,Guru Jambheshwar University of Science and Technology | Garg V.K.,Guru Jambheshwar University of Science and Technology | Gautam Y.P.,Environmental Survey Laboratory | Kumar A.,Environmental Survey Laboratory
Journal of Radioanalytical and Nuclear Chemistry | Year: 2015

This field study was undertaken to quantify the transfer factor of 137Cs from agricultural soil to wheat grains and ingestion dose evaluation around Narora Atomic Power Station, Narora, India from 2010 to 2012. 137Cs activity was measured using NaI (Tl) well type gamma-spectrometry system. Transfer factor of 137Cs from soil to wheat grain samples was in the range of 0.12–0.46. Annual ingestion dose to man from 137Cs activity was significantly lower than permissible limit (1.0 mSv year−1). The risk measured due to 137Cs is also insignificant to members of public residing around Narora Atomic Power Station, Narora, India. © 2014, Akadémiai Kiadó, Budapest, Hungary.

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