Radioelemental study of Kolaghat, thermal power plant, West Bengal, India: possible environmental hazards

Coal combustion in power plants in India produces large quantities of coal-related wastes, e.g. fly ash and bottom ash. Indian coals used in power stations are of high ash content, thus resulting in the generation of large amounts of fly ash (similar to100 million tons/year) Combustion of coal results in enhanced concentration of most radionuclides found in waste materials. In the present work, an attempt has been made to assess the radiological impact of the Kolaghat thermal power plant in West Bengal, India. The fly ashes and coal from the power plant were analysed for U-238, Th-232 and K-40 by a NaI (Tl)-based gamma-ray spectrometer. The results show that Ra-226, and Th-232 range from 81.9-126 and 132-169 Bq/kg in fly ash and 25-50 and 39-55 Bq/kg in coal. These results are high compared to those of other thermal power plants of India. Hence, the Kolaghat fly ash has a significant amount of radioactivity which, if not, properly disposed, will be a serious threat to the ambient environment.