Natural radioactivity in waste generated from non-nuclear industries

It is well known that a number of large scale non-nuclear industries use raw material and produce waste which contains natural radioactivity. Thermal Power Plant (TPP) and Phosphate Fertilizer Plant (PFP) are the two major industries in India which produce huge amount of waste containing elevated levels of natural radioactivity. The main concern about these radioactive wastes is that they are openly dumped in the disposal ponds which may lead to spread of this radioactivity to public domain via air or ground water route. In TPP, coal, like other geological materials contains trace amounts of natural radionuclides and their daughter products which lead to discharge of these radionuclides by combustion in coal-fired thermal power stations. The ash which is dumped in ash ponds contains 2-5 times elevated levels of the natural radioactivity. Similarly, phosphogypsum is a waste by-product from the processing of phosphate rock containing natural radionuclides for fertilizer production. In this study, the activity concentrations of naturally occurring radionuclides in coal from feeders, and ash from ash pond collected from various coal-fired power plants alongwith the rock phosphate samples from feeders and phosphogypsum samples from gypsum ponds collected from various phosphate fertilizer plants across India were determined using alpha and gamma spectrometry