Depth Wise Radiological Analysis of Sediment Sands in Cauvery and Kollidam Rivers in Tiruchirappalli District, Tamilnadu, India

The specific activity of primordial radionuclides (U, Th and K) in the sediment sand of different depth-wise samples in Cauvery and Kollidam rivers in Tiruchirappalli district, Tamil Nadu, India, were estimated using NaI (Tl) gamma ray spectrometry. The mean activities of the radionuclides of all the sediments (depth-wise samples) were 10.4 Bq.Kg, 22.65 Bq.Kg and 310 Bq.Kg respectively. The average amount of dose rate was 30.28 nGyh which is less than the value of 55 nGyh proposed by UNSCEAR. The calculated mean value of radium equivalent lie below the recommended limit of 370 Bq.Kg given by OECD. The exhalation rate of radiogenic gases, radon and thoron from the daughter products of the radionuclides were estimated using SRM radon monitor and RAD-7 detector found to be lie within the recommended limits. From the analysis it is suggested that the sediment sands do not pose any radiological significance to the public and can be used for the construction purposes along with other building materials.