A day after the radiation leakage at the Kaiga power plant in Uttar Kannada district came to light, the Centre on Sunday said it suspected “mischief” by some persons who contaminated the water cooler which exposed a section of workers to excessive radiation.
The top brass of the Department of Atomic Energy (DAE) asserted that there was neither radioactive threat to the environment nor to all workers of the nuclear plant. The incident took place on November 25 when the first unit (220 MWe) had been shutdown for maintenance.
“Preliminary inquiry does not reveal any violation of operation procedures or radioactivity releases or security breach. It is possibly an act of mischief,” said S K Jain, Chairman and Managing Director of the Nuclear Power Corporation of India Ltd (NPCIL) that runs all Indian nuclear power stations.
Jain said any contamination caused by heavy water in the human body is quickly flushed out through urination and perspiration, which could be hastened through medication.
However, the delay in issuing clarification to the media and the recent incidents of the deaths of scientist Mahalingam and employee Ravimoole have left doubts on the issues of security and maintenance at the plant.
‘Malevolent act’
Meanwhile, Atomic Energy Commission (AEC) Chairman Anil Kakodkar said in Mumbai: “Somebody deliberately put the tritiated water vials into a drinking water cooler.
Therefore, we are investigating who is behind the malevolent act.” He added that those found guilty would be punished under the Atomic Energy Act. “Investigations are being carried out from two angles. First to ascertain as to who contaminated the water cooler with tritiated heavy water, and the second from radiation protection angle,” Kakodkar said.
In the capital, Union Minister for Science and Technology Prithviraj Chavan said a high-level probe had been instituted to probe the sabotage. The Kaiga complex houses three 220 MWe operational nuclear plants. The fourth one is in an advanced stage of completion.
While Kaiga-1 is shut due to annual maintenance, Kaiga-2 and 3 are functioning normally.
Radioactivity was found in some employees during their routine health screening on November 24, necessitating detailed medical check up for 45-50 of them at the plant hospital at Mallapur, next day. A team from the Atomic Energy Regulatory Board (AERB) was sent to the north Karnataka nuclear plant to investigate the leak. The nuclear regulators found that contamination was caused by a specific form of heavy water in which regular hydrogen has been replaced with its heavier cousin tritium. Heavy water is used in nuclear power plants as moderator to control the chain reaction.
The secretary of the AERB, Dr Om Pal Singh stated in a press release that All persons working in the plant were checked and personnel found to have received any tritium uptake were referred to the hospital for administration of diuretics. Presently only two persons are left with tritium in their body. This tritium could cause their extrapolated annual radiation exposure to marginally exceed the AERB specified limit of 30 milli-sievert.
In the next few days the potential radiation exposure among the two would be brought down to normal condition. The other persons are in normal state and are back to duty. As there is no heavy water leak in the plant, it appears to be the handiwork of miscreants, Singh said.
Source isolated
“The source of tritium uptake is due to consumption of water from one of the water coolers, which was contaminated. The water cooler was isolated and put out of use,” said Kaiga station director J P Gupta.
He said investigations revealed that the water cooler was contaminated, and as a precautionary measure, body samples of all the workers were analysed and based on it, a few were sent for medical consultation.
Uattara Kannada district Parisara Samrakshana Samiti President Ananth Hegde Ashisara has demanded that the Kaiga nuclear plant management should allow an independent body to probe into the drinking water contamination.
He said, “If tritium has been leaked into environment, then its deadly effect will persist for at least 12 years. It is unfortunate that even before the investigation is completed, the AEC Chairman has announced that contamination is a foul play.”
Hegde said that Green Peace, CANE, Bangalore and the Samiti wanted the Kaiga management to conduct health check-up of villagers residing near the plant. They will hold a meet on Monday to chalk out next plan of actions.