Sunday, March 13, 2011

Japan nuclear episode: Nuclear mining and power plants in India safe, says Barc scientist

Syed Akbar
Hyderabad, March 13: Nuclear mining and power plants in the country are safe and the environmental radiation levels released by them are quite low and negligible.
According to Dr VD Puranik, head of the environmental assessment division of Bhabha Atomic Research Centre, radiation exposures to the general public due to the operations of nuclear units like beach mineral separation, monazite processing, uranium mining and milling, and fuel fabrication "are not significant".
Dr Puranik has carried out extensive work on the radiological and environmental safety aspects of nuclear mining and power units in the country. His findings that "the environmental radiation levels are low and often close to the local background level" gain significance in the backdrop of apprehensions that nuclear power operations in the country are not safe. Radiological pollution and its impact on health has been the focus of discussion in the country after the nuclear mishap in Japan.
Analysis of data by Dr Puranik has revealed that even for those closely associated with these units, the average annual effective dose in the beach sand mining and processing of monazite and thorium are between 1 and 7 mSv (mean dose). The dose in any worker does not exceed the annual dose limit of 20 mSV prescribed by the Atomic Energy Regulatory Board. For uranium refining and fuel fabrication plants, like the Nuclear Fuel Complex in Hyderabad, the average annual effective dose are around 1 to 2 mSv.
The front end nuclear fuel cycle in India comprises mining and processing of beach mineral sands along the southern coasts of Kerala, Tamil Nadu and Orissa, mining and processing of uranium ore in Singhbhum-East in Jharkhand, and refining and fuel fabrication in Hyderabad.
Magnesium di-uranate from uranium mill at Jaduguda is purified in uranium processing and fuel fabrication plant of NFC in the city, where nuclear grade uranium oxide is produced for use in fuel assemblies for power reactors.
Operation of the facilities, from mining of beach mineral sands and uranium ore and processing to purification of uranium to fabrication of fuels involves exposure of workers to varying levels of external and internal radiation. As against the upper annual dose limit of 20 mSv, a dose of 5 mSv has been observed at Jaduguda, 5.5 mSv at Bhatin, 4 mSv at Narawa, 1 mSv at NFC, and 5.5 mSv at Udyogamandal.
Dr Puranik, while analysing the average values of uranium and radium in ground water at locations more than 5 km from the tailings pond of these units, observed "there seems to be no movement of radio-nuclides from the tailings pond to the ground water in the vicinity.
In Hyderabad wells and bore wells up to 5 km from NFC are monitored on regular basis for conventional pollutants and radioactivity. Ambient air quality is also measured. The levels are found to be "within the limits" and there's no environmental impact on twin cities.

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