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Abstract: The indoor radon concentration was estimated based on the radon flux in soil and groundwater. The indoor radon concentration in Budhakedar area of Garhwal Himalaya, India is estimated to be 3.0–131.4Bq/m3 in summer and 4.6–92.4Bq/m3 in winter. Based on the available data from study area, the calculated value of diffusion coefficient for the soil ranges from 0.1×10−2 to 3.0×10−2 cm2 s−1 in the summer season and 0.1×10−2 to 0.4×10−2 cm2 s−1 in the winter season. The calculated value of diffusion flux in the study area is found to vary from 0.1×10−2 to 16.1×10−2 Bqm−2 s−1 in summer season and 0.1×10−2–12.2×10−2 Bqm−2 s−1 in winter season. The formulation was tested by comparing the results of radon values from two different seasons of a year. [Copyright &y& Elsevier]

Abstract: The radon content in groundwater sources depends on the radium concentration in the rock of the aquifer. Radon was measured in water in many parts of the world, mostly for the risk assessment due to consumption of drinking water. The exposure to radon through drinking water is largely by inhalation and ingestion. Airborne radon can be released during normal household activities and can pose a greater potential health risk than radon ingested with water. Transport of radon through soil and bedrock by water depends mainly on the percolation of water through the pores and along fractured planes of bedrock. In this study, radon concentration in springs and hand pumps of Kumaun and Garhwal Himalaya, India was measured using radon emanometry technique. The study shows that radon concentration in springs and hand pumps is controlled by geohydrological characteristics, which in turn is also governed by tectonic processes. [Copyright &y& Elsevier]

Radon was measured in soil-gas and groundwater in the Budhakedar area of Tehri Garhwal, India and related to the gamma dose rate in the same area. A laboratory experiment was also performed to measure the radon exhalation rate from soil samples collected from the same area. Radon exhalation rate from collected soil samples was found to vary from 0.1×10-5 Bq·kg-1·h-1 to 5.7×10-5 Bq·kg-1·h-1 with an average of 1.5×10-5Bq·kg-1·h-1. Radon concentration in soil and groundwater of the Budhakedar area varies from 1098 to 31,776 Bq·m-3 with an average value of 7456 Bq·m-3, and from 8 to 3047 Bq·L-1 with an average value 510 Bq·L-1, respectively. Surface gamma dose rate in the study area varied from 32.4 to 83.6 μR·h-1 with an overall mean of 58.7 μR·h-1. The observed value of the gamma dose rate was not found to be related to the value of radon concentration in groundwater but a weak positive correlation was observed between the gamma dose rate and soil-gas radon concentration. A weak negative correlation was observed between radon exhalation rate from soil and radon concentration in the soil. Radon exhalation rate from the soil was also not found to be correlated with the gamma dose rate, while it shows a positive correlation with radon concentration in water. [ABSTRACT FROM AUTHOR]

Abstract: Environmental radiation exists as a consequence of cosmic, terrestrial and man made sources. Terrestrial radiation are emitted from natural radionuclide present in varying amounts in all types of soils, rocks, air, water and other environmental materials; radon is emitted from the soil surface, although secondary contributors include the oceans, natural gas, geothermal fluids, volcanic gases, ventilation from caves and mines, and combustion of coal. Radon and thoron levels were measured in soil-gas, ground water and indoor air in Budhakedar area of Tehri Garhwal, India. Radon concentrations in soil and groundwater of the Budhakedar area were found to vary from to with an average value and to with mean value , respectively. Measurement of indoor radon, thoron and their daughter products were also measured in the houses of the same area for four different seasons (autumn, winter, summer and rainy) using LR–115 plastic track detectors. The detector is fixed in a twin chamber radon dosimeter, which can record the values of radon, thoron and their decay products separately. The film fixed in bare mode holder gives the concentrations of radon, thoron and their progeny while the films fixed inside the cup with filter and membrane modes give the concentrations of radon/thoron gases and of pure radon gas, respectively. Detailed analysis of the effects of seasonal variation on radon, thoron and their decay products inside the houses are reported in this paper. [Copyright &y& Elsevier]

Abstract: Research on earthquake-related radon monitoring has received enormous attention recently. Anomalous behaviour of radon in soil and groundwater can be used as a reliable precursor for an impending earthquake. While earthquake prediction may not yet be possible, earthquake prediction research has greatly increased our understanding of earthquake source mechanisms, the structural complexities of fault zones, and the earthquake recurrence interval, expected at a given location. This paper presents some results of continuous monitoring of radon in soil-gas in Garhwal Himalaya, India. Daily soil-gas radon monitoring with seismic activity and meteorological parameters were performed in the same laboratory system, located at H.N.B. Garhwal University Campus, Tehri Garhwal, India. Radon anomalies along with meteorological parameters were found to be statistically significant for the seismic events within the magnitudes M2.0-M6.0 and epicentral distances of 16–250km from the monitoring station. The frequent positive and negative anomalies with constant environmental perturbation indicate the opening and closing of micro cracks within the volume of dilatancy by strain energy. The spike-like and sharp peak anomalies were recorded before, during and after earthquakes occurred in the area. The variations in radon concentrations in soil-gas are found to be correlated with seismic activities in the Garhwal Himalaya. The correlation between radon level and meteorological parameters is also discussed. [Copyright &y& Elsevier]

Abstract: This paper presents the results of investigation of radon levels in the soil–gas and groundwater of Uttarkashi, India within the distance of 5km in vertical and horizontal directions from the landslide of Varunawat hill. Radon release from the soil and groundwater was found higher than the normal values. Radon concentration in groundwater over and around the landslide was found to vary from 0.51 to . The soil–gas radon concentration was found to vary from 219 to along the slope of landslide. Radon exhalation rate in collected soil samples was found to vary from to . Radon values were not found correlated with major and trace element contents in the upper soil of the area, which indicate that the migration of radon from deeper part of the earth along with landslide contribute to the surface radon concentration. Recorded values show a close association with local geology and Varunawat eruptions. [Copyright &y& Elsevier]