Some Indian experts have warned that the explosion at Japan’s Fukushima Daiichi nuclear complex may be worst than Chernobyl even as the quake-hit nation seeks to reassure its people that the country would not experience a full- blown nuclear disaster. At least 15 people have been reportedly admitted to hospital with symptoms of radiation poisoning after a blast ripped through a reactor at the Fukushima nuclear power plant yesterday. The emergency cooling system is said to have been failed at another reactor at the Fukushima plant.
The explosion at the Fukushima plant is the third worst nuclear incident in history, after Chernobyl and Three Mile Island. Major design flaws were blamed for Chernobyl in April 1986, when overheating caused two massive explosions at the Ukraine plant. Huge clouds of radioactive material escaped into the atmosphere and travelled hundreds of miles across Europe.
The disaster produced 100 times more radiation than the Nagasaki and Hiroshima bombs and has been blamed for 200,000 deaths from cancer and other diseases. The March 1979 Three Mile Island accident in Pennsylvania in the US was similar to Fukushima because a fault caused overheating. Although the plant suffered a “severe core meltdown” only small amounts of radiation escaped.
"There are a total of 10 reactors at the two plants at Fukushima nuclear complex. Yesterday, there was an explosion at the No. 1 nuclear plant in the wake of 8.9 magnitude quake and tsunami in the region, which destroyed a reactor and reports suggest that another reactor may also explode," said Delhi-based nuke security expert V.K. Duggal.
"The Japanese government hasn’t yet provided accurate information regarding threat posed by explosions. This is very worrying. The disaster may turn out to be more dangerous than Chernobyl — both from the standpoint of population’s exposure to radioactive material and radioactive contamination in the area," said Duggal.
Another expert Professor Subodh Gupta agreed. "We aren’t at all aware of the status of the fuel in the core of the reactor that exploded yesterday at the nuclear complex. We don’t know whether the core is uncovered, if the fuel is breaking up or melting. This is dangerous," he said. Japan’s nuclear safety agency has rated the incident at four on the international scale of zero to seven. The country’s US envoy Ichiro Fujisaki told CNN "there was a partial melt of a fuel rod… but it’s nothing like a whole reactor melting."
Fears of another explosion at a Japanese nuclear plant are growing after officials said the cooling system in a second reactor had failed. Thousands of people were evacuated on Saturday following an explosion and leak from the Fukushima Daiichi plant, 240 km (150 miles) north of Tokyo. It was believed the first explosion had been contained and disaster avoided.
But on Sunday the plant operator, Tokyo Electric Power (TEPCO) said radiation levels around the Fukushima Daiichi plant had risen above the safety limit and said the cooling system in the number three reactor had failed. Workers continued efforts to cool down fuel rods inside two nuclear reactors Sunday as a government official warned that a second explosion could occur at the nuclear plant. Chief Cabinet Secretary Yukio Edano said an explosion could take place in the building housing the No. 3 reactor at the Fukushima Daiichi plant in northeastern Japan.
"There is a possibility that the third reactor may have hydrogen gas that is accumulating in the reactor (that) may potentially cause an explosion," he said. An explosion caused by hydrogen buildup Saturday blew the roof off a concrete building housing the plant’s No. 1 reactor, but the reactor and its containment system were not damaged in the explosion.
Edano said the No. 3 nuclear reactor would also likely withstand a similar blast, noting that workers had already released gas from the building to try to prevent an explosion.
Workers have been scrambling to cool off fuel rods at both reactors after a massive earthquake and tsunami disabled their cooling systems. Japanese authorities have said there is a "possibility" that a meltdown has occurred in the reactors.
A meltdown is a catastrophic failure of the reactor core, with a potential for widespread radiation release. But Japanese officials stressed that there were no indications of dangerously high radiation levels in the atmosphere around the two reactors at the Fukushima Daiichi nuclear plant in northeastern Japan. They said they were unable to confirm whether a meltdown had occurred because they cannot get close enough to the reactors’ cores.
Workers were pumping seawater into the reactors in what one expert described as an "act of desperation" to cool them down. As official information about the crisis trickled out, scientists and experts around the world weighed in on the situation, offering a wide range of interpretations of the events and their possible consequences.
If the effort to cool the nuclear fuel inside the reactor fails completely, the resulting release of radiation could cause enormous damage to the plant or release radiation into the atmosphere or water. That could lead to widespread cancer and other health problems, experts say.
The problems at the Daiichi plant began Friday, when the 8.9-magnitude quake that struck offshore forced the automatic shutdown of the plant’s nuclear reactors and knocked out the main cooling system, according to the country’s nuclear agency. A tsunami resulting from the quake then washed over the site, knocking out backup generators.
The reactors at the Fukushima Daiichi plant are boiling-water reactors. The reactor affected by Saturday’s explosion is Fukushima Daiichi 1. It was connected to the grid in November 1970, making it about 40 years old. The No. 1 unit is the oldest of six reactors at the Fukushima Daiichi site, according to the World Nuclear Association.
Japan is heavily dependent on nuclear power, with 54 plants and another eight slated for construction, said Aileen Mioko Smith of Green Action, an environmental group. All are located in "very seismic" areas, she said. Authorities have also detected cooling system problems at another nuclear facility in Fukushima Prefecture, the Fukushima Daini plant, but have not expressed any concerns about possible meltdowns there.
Government officials revealed plans to distribute iodine tablets – a treatment for radiation poisoning – to locals while a 20km exclusion zone was set up round the plant. Residents outside the zone were urged to stay inside, close doors and windows and turn off air conditioning. Scientists had detected eight times the normal radiation levels outside the facility and 1,000 times normal levels inside the affected unit’s control room.
Japan’s prime minister, Naoto Kan, declared a state of emergency at the crippled unit and at its sister plant, the Fukushima Daini, as engineers tried frantically to determine whether the reactor had gone into meltdown. Japan’s nuclear safety agency said the number of people exposed to radiation could reach 160. Officials said radiation levels around the plant had breached saftey levels.
Those opposed to nuclear power will not let the incident be forgotten, as Jan Beranek, head of Greenpeace’s international nuclear campaign, made clear. "How many more warnings do we need before we finally grasp that nuclear reactors are inherently hazardous? The nuclear industry always tells us that situation like this cannot happen with modern reactors, yet Japan is currently in the middle of a potentially devastating nuclear crisis," he said.
"The disaster could be on the scale of Chernobyl where the reactor core melted and radioactive fallout were discharged into the air, harming civilians living at a relatively great distance from the reactor. It’s high time that Japan comes out with a correct assessment of the situation," said Professor Gupta.