Rashme Sehgal | Rediff
The Atomic Energy Regulatory Board believes the Kakrapar Atomic Power Station’s unit 1 in Gujarat, which had shut down in March due to a ‘radioactive leak’, will take another eight months or so to restart.
S Harikumar, secretary, AERB, has clarified that the leak has been arrested and investigations into the reason for the leak are ongoing.
Phase I of this operation comprised detecting the leak which is currently in a “cold shut-down,” state, Harikumar pointed out, while all other systems are functioning normally. They are currently in phase II which looks at investigations behind the leak.
Following the isolation of the leaky channel, Harikumar elaborated, “The plant emergency has been terminated at KAPS. There has not been any report of abnormal radioactivity releases or of radiation exposures to any personnel following this leak which occurred on March 11, 2016.”
These investigations are expected to continue for some more months.
“We are currently doing non-destructive testing, which involves going into the details. We cut the channels that have seen the leak and sent it to the Bhabha Atomic Research Centre for testing,” the AERB secretary added.
“At every stage of these investigations, we have to secure permission from the AERB. However, we are also using this as an opportunity to do plant maintenance, which was also due.”
Nuclear physicist Dr M V Ramana from Princeton University is not satisfied with the AERB’s explanation and questions how the AERB can make a blanket statement stating, ‘There has not been any report of abnormal radioactivity releases/radiation exposures to any personnel during this incident.’
“There is little doubt that this leak would have exposed workers to tritiated water vapour and they would have had some radiation exposure,” Dr Ramana said.
“There are two ways of interpreting this claim. One possibility is that the exposure levels were really not abnormal. That would imply that workers in general are exposed to the levels of radiation that are created during a large heavy water leak as happened earlier this year at Kakrapar,” Dr Ramana added.
“This does not speak well of the levels of occupational safety at Kakrapar and, by extrapolation, at the other nuclear power plants operated by NPCIL (Nuclear Power Corporation India Limited),” he felt.
“The second possibility is that the workers involved in the Kakrapar clean-up did indeed get abnormally high levels of radiation. That possibility does not engender trust in the AERB. Neither of these possibilities are comforting,” Dr Ramana said.
His concern is primarily with knowing the cause of the leak.
“When the cause of the leak is identified, is the AERB going to order a shutdown of all the other pressurised heavy water reactors in the country to fix the underlying problem?” Dr Ramana asked, adding, “Whether or not the AERB does that will reveal how much it prioritises safety over other goals.”
Dr Rajendra Kumar, district magistrate, Surat district, who had come in for some criticism by farming communities for not speaking upfront on this leak, strongly denied the charge. “I was informed at 3.40 pm (on March 11) and I held a press conference on this subject the same day,” the DM said.
“The government has a very strict protocol for nuclear emergencies,” Dr Kumar said. “The plant is run by the NPCIL and onsite emergencies are handled by it and the AERB. We look at the offsite situation.”
“Scientists from the Plasma Research Laboratory in Ahmedabad were informed immediately and they rushed here within three hours of being informed on the same day,” the DM added. “They did offsite monitoring and did not find any radioactivity in the soil or in the water bodies.”
On receiving the PRL team’s findings, Dr Kumar said, “We felt there was no need to conduct any emergency drill,” though he did concede, “It (KAPS) is a very strategic site and therefore great care was taken to ensure emergency protocols were observed.”
Evaluating the current situation, Dr A Gopalakrishnan, the former AERB chairman, said, “The AERB has given the assurance that they have stopped the leak of heavy water. We have no way of verifying this. We have to take them at their word.”
On the issue of workers being exposed to increased radiation within the plant when the accident occurred, Dr Gopalakrishnan said, “There may have been a very brief exposure — the maximum it must have been there for a day or two.”
“The AERB knows any misstep will see them in deep trouble,” Dr Gopalakrishnan said. “That is why I do not believe they will mislead us. This is an imperfect system of communication, but this situation has been prevailing from 1983.”
“f the fuel is intact and there is no indication otherwise,” he added, “then the delay is basically because they (AERB) themselves are trying to figure out how the leak occurred.”
“They need to get enough technical evidence on what happened. Is it confined or is it a characteristic problem in which case all the coolant pipes will need to be re-tubed?” Dr Gopalakrishnan said.
“We have to find out which end of spectrum this belongs to for which AERB will need to do more investigation,” he added. “Rushing them will not help, the present slow and steady approach is the right approach.”
The Kakrapar reactor belongs to the group of Canada deuterium uranium reactors which over the years have been known to face degradation of hundreds of pipes that hold the fuel and transport heavy water.
The Canadian government had informed AERB that the tubes were facing a problem and their metallurgists had added new alloy as part of this strengthening device. Kakrapar was the last reactor in this series to be re-tubed.
“This is Kakrapar’s second re-tubing,” Dr Gopalakrishnan said. “The life of a re-tubing is around 20 to 25 years, and the second re-tubing was done 2 to 3 years ago. The present ones are brand new tubes, which have only gone through 10 per cent of their life.”
“It is perplexing why this has happened,” he said. “We did not expect these new tubes to have ruptured.”
Critical of AERB’s handling, Dr Gopalakrishnan believes, “We are standing on false pride and by now should have got the Canadian government to assist us in handling this problem. Rather than beating our chests and saying ‘I can solve it,’ we should have got together with three to four countries which have these reactors.”
“There is no harm in putting our heads together to resolve this problem. India is no longer a nuclear pariah. We need to work collectively. If you want to behave like a nuclear power, then we need to use the heads of everyone, especially when the Canadians are a friendly country.”
Greenpeace, which works on nuclear issues, believes AERB failed in its handling of this issue. , “The primary and the most important responsibility of a nuclear regulator in the event of an accident is regular and continuous updates,” Hofeza Merchant, a nuclear campaigner, said.
“These updates need to have usable information in them and not just empty assurances,” Merchant added. “During the Kakrapar accident, the emergency lasted for 11 days and updates were only provided three times. These three updates contained assurances and no usable information.”
“Just as important it is to investigate the cause of the leak,” Merchant said, “it is equally important to investigate the handling of the accident. In case of the Kakrapar accident, the regulator clearly failed at providing usable information.”
“Empty assurances provided by the regulator caused more stress than relief for those that reside close to the reactor.”