Accidents at nuclear power plants in India

Below is a list of leaks, fires and structural damages that have occurred in India’s civilian nuclear power sector.  Numerous other examples of oil leaks, hydrogen leaks, fires and high bearing vibrations have often shut plants, and sometimes not (1).

As the Department of Atomic Energy is not obliged to reveal details of ongoings at these plants to the public, there may be many other accidents that we do not know about.

April 2011 Fire alarms blare in the control room of the Kaiga Generating Station in Karnataka.  Comments by officials alternately say there was no fire, that there was only smoke and no fire, and that the fire was not in a sensitive area (2).  Details from the AERB are awaited.

November 2009 Fifty-five employees consume radioactive material after tritiated water finds its way into the drinking water cooler in Kaiga Generating Station. The NPCIL attributes the incident to “an insider’s mischief” (3).

April 2003 Six tonnes leak of heavy water at reactor II of the Narora Atomic  Power Station (NAPS) in Uttar Pradesh (4), indicating safety measures have not been improved from the leak at the same reactor three years previously.

January 2003 Failure of a valve in the Kalpakkam Atomic Reprocessing Plant in Tamil Nadu results in the release of high-level waste, exposing six workers to high doses of radiation (5). The leaking area of the plant had no radiation monitors or mechanisms to detect valve failure, which may have prevented the employees’ exposure. A safety committee had previously recommended that the plant be shut down.  The management blames the “over enthusiasm” of the workers (6).

May 2002 Tritiated water leaks from a downgraded heavy water storage tank at the tank farm of Rajasthan Atomic Power Station (RAPS) 1&2 into a common dyke area.  An estimated 22.2 Curies of radioactivity is released into the environment (7).

November 2001 A leak of 1.4 tonnes of heavy water at the NAPS I reactor, resulting in one worker receiving an internal radiation dose of 18.49 mSv (8).

April 2000 Leak of about seven tonnes of heavy water from the moderator system at NAPS Unit II. Various workers involved in the clean-up received ‘significant uptakes of tritium’, although only one had a radiation dose over the recommended annual limit (9).

March 1999 Somewhere between four and fourteen tonnes (10) of heavy water leaks from the pipes at Madras Atomic Power Station (MAPS) at Kalpakkam, Tamil Nadu, during a test process. The pipes have a history of cracks and vibration problems (11) . Forty-two people are reportedly involved in mopping up the radioactive liquid (12).

May 1994 The inner surface of the containment dome of Unit I of Kaiga Generating Station collapses (delaminates) while the plant is under construction. Approximately 130 tonnes of concrete fall from a height of nearly thirty metres (13), injuring fourteen workers. The dome had already been completed (14), forming the part of the reactor designed to prevent escape of radioactive material into the environment in the case of an accident.  Fortunately, the core had not then been loaded.

February 1994 Helium gas and heavy water leak in Unit 1 of RAPS.  The plant is shut down until March 1997 (15).

March 1993 Two blades of the turbine in NAPS Unit I break off, slicing through other blades and indirectly causing a raging fire, which catches onto leaked oil and spreads through the turbine building.  The smoke sensors fail to detect the fire, which is only noticed once workers see the flames.  It causes a blackout in the plant, including the shutdown of the secondary cooling systems, and power is not restored for seventeen hours.  In the meantime, operators have to manually activate the primary shutdown system.  They also climb onto the roof to open valves to slow the reactions in the core by hand (16).  The incident was rated as a Level 3 on the International Nuclear Event Scale, INES.

May 1992 Tube leak causes a radioactive release of 12 Curies of radioactivity from Tarapur Atomic Power Station (17).

January 1992 Four tons of heavy water spilt at RAPS (17).

December 1991 A leak from pipelines in the vicinity of CIRUS and Dhruva research reactors at the Bhabha Atomic Research Centre (BARC) in Trombay, Maharashtra, results in severe Cs-137 soil contamination of thousands of times the acceptable limit. Local vegetation was also found to be contaminated, though contract workers digging to the leaking pipeline were reportedly not tested for radiation exposure, despite the evidence of their high dose (18).

July 1991 A contracted labourer mistakenly paints the walls of RAPS with heavy water before applying a coat of whitewash. He also washed his paintbrush, face and hands in the deuterated and tritiated water, and has not been traced since (19).

March 1991 Heavy water leak at MAPS takes four days to clean up (20).


Sources
1 For more details, see ‘Safety First? Kaiga and Other Nuclear Stories’ by M.V. Ramana and Ashwin Kumar, Economic & Political Weekly, Vol XLV No. 7, 13 February 2010.  The article lists many of the accidents shown here, and others.
2 M. Raghuram, “Kaiga officials are tight-lipped about control room fire” DNA, 11 April 2011;
“It was a faulty fire alarm, says Kaiga Director”, ndtv.com, 11 April 2011.
3 T.S. Subramanian, ‘Kaiga workers “back to work”’, The Hindu, 29 November 2009
4 Annual Report for the Year 2003-2004, Atomic Energy Regulatory Board, Mumbai.
5 S. Anand, ‘India’s Worst Radiation Accident’, Outlook, 28 July 2003, 18-20
6 M.R. Venkatesh, ‘BARC Admits Radiation Error’, Telegraph, 7 August 2003
7 Annual Report for the Year 2002-2003, Atomic Energy Regulatory Board, Mumbai.  
8 Annual Report for the Year 2001-2002, Atomic Energy Regulatory Board, Mumbai.
9 Annual Report for the Year 2000-2001, Atomic Energy Regulatory Board, Mumbai.
10 The figure is contested – see T. S. Subramanian, “An Incident at Kalpakkam,” Frontline, 23 April 1999
11 T.S. Gopi Rethinaraj, ‘In The Comfort Of Secrecy,’ Bulletin of the Atomic Scientists, 55 (6) 52-57, 1999
12 T.S. Subramanian, “An Incident at Kalpakkam”, Frontline, Vol 16, Issue 8, 23 April 1999
13 Buddhi Kota Subbarao, ‘India’s Nuclear Prowess: False Claims and Tragic Truths’, Manushi 109, 1998
14 Sanjay Havanur, “The Dome of Death”, Anumukti, 7 (6):4-5, 1994
15 T.S. Subramanian, ‘Reviving Reactors’ Frontline, Vol 14, No. 26, Dec 1997 - Jan 1998
16 M.V. Ramana and Ashwin Kumar, ‘Safety First? Kaiga and Other Nuclear Stories’, Economic & Political Weekly, Vol XLV No. 7, 13 February 2010
17 Greenpeace, Calendar of Nuclear Accidents and Events http://archive.greenpeace.org/comms/nukes/chernob/rep02.html
18 Chinai, Rupa: “Radioactive Leakage at the Bhabha Atomic Research Centre”, The Sunday Observer, 6 September 1992   
19 RP “A Heavy Whitewash”, translated from Hindi, Rajasthan Patrika, 21 August 1991   
20 “National Symposium on Safety of Nuclear Power Plants and Other Facilities”, Bhabha Atomic Research Centre, Trombay, Bombay.