Plutonium traces in Fukushima soil

Government says levels are not harmful to human health as anxiety grows over leaks at stricken nuclear power plant Traces of plutonium have been found in the soil at the Fukushima Daiichi nuclear power plant, Japanese officials said on Monday, but not at levels considered harmful to human health. The discovery of plutonium – a byproduct of nuclear reactions – added to anxiety over the stricken plant, 150 miles north of Tokyo. Earlier, the government confirmed that levels of radioactivity in water leaking from a reactor at the facility resulted from a partial meltdown of fuel rods, amid growing fears that radiation may also have seeped into seawater and soil. The plant’s operator, Tokyo Electric Power [Tepco], said readings of plutoinium-238, 239 and 240 were similar to those recorded in other parts of Japan after nuclear tests conducted overseas. “I apologise for making people worried,” Tepco’s vice president, Sakae Muto, told reporters. “It’s not at a level that’s harmful to human health.” But an official from Japan’s nuclear safety agency was more cautious. “While it’s not at a level harmful to human health, I am not optimistic,” Hidehiko Nishiyama said. “This means the containment mechanism is being breached, so I think the situation is worrisome.” Tepco has yet to determine the source of the plutonium, although it appeared that in two places, the radioactive element had come from reactors rather than from the atmosphere. One of the plant’s three reactors contains plutonium in its fuel mix. Meanwhile, contamination in a pool of water in the turbine building of the No 2 reactor was found to be 100,000 times normal levels, Tepco said. On Sunday the firm said the figure was 10m times higher, a mistake the government’s chief spokesman, Yukio Edano, said was “absolutely unforgivable”. Tepco was forced into another embarrassing apology after it admitted it had twice named the wrong isotope in its corrections about the levels of radiation. “On one hand, I do think the workers at the site are getting quite tired,” Edano told reporters. “But these radiation tests are being used for making various decisions on safety … they are absolutely unforgivable.” In addition, radiation above 1,000 millisieverts per hour was found in surface water in concrete tunnels outside the No 2 reactor, Tepco said. It added that the tunnels did not lead to the sea, but conceded it could not rule out that radioactive water had seeped into the ground. Greenpeace, meanwhile, said that it had recorded radiation levels of up to 10 microsieverts per hour in Iitate, a village 25 miles from the plant, and urged authorities to expand the evacuation zone from its current 12-mile radius. “It is clearly not safe for people to remain in Iitate, especially children and pregnant women, when it could mean receiving the maximum-allowed dose of radiation in only a few days,” said Jan van de Putte, the group’s radiation safety expert. “When further contamination from possible ingestion or inhalation of radioactive particles is factored in, the risks are even higher.” Tepco has reportedly asked the French nuclear sector for assistance, seeking help from Electricite de France, Areva and the Nuclear Energy Agency, a research body, according to Eric Besson, France’s industry and energy minister. Japan’s nuclear and industrial safety agency (Nisa) said radioactive iodine-131 of 1,150 times the maximum allowable level had been detected in seawater near drainage outlets serving four of Fukushima’s reactors. Nisa’s spokesman Hidehiko Nishiyama said he suspected radioactive water from the plant was leaking into the sea. On Sunday he had denied any connection. Edano said partial meltdown had probably occurred when the plant was hit by the tsunami on 11 March, adding that there was no evidence of subsequent meltdown. Four of the facility’s six reactors have yet to be made safe, while efforts are continuing to pump in fresh water to prevent a far more dangerous full meltdown. “The radiation seems to have come from fuel rods that were partially melted down and came into contact with the water used to cool the reactor,” Edano said. “Steam may have condensed … carrying water from within the containment vessel.” Airborne radiation has been confined to the reactor buildings, and work to remove contaminated water from the structures continued on Monday. Setbacks to attempts to cool the reactors, and the realisation the crisis is far from over, have added to the plight of tens of thousands of people living nearby. Sakae Muto, vice-president of Tepco, said: “Regrettably, we don’t have a concrete schedule at the moment to enable us to say how many months, or years it will take [to make the plant safe].” About 70,000 people within a 12-mile radius of the Fukushima plant were evacuated soon after the disaster, while a further 130,000 people living in a 12-20-mile radius have been told to stay indoors. The government said that it had no plans to widen the evacuation zone. It is not known exactly how many people remain in the outer zone. Many have left voluntarily after days without essential supplies and services. Truck drivers are refusing to enter the zone, fearing radiation exposure. The government created confusion last week when it advised people within a 20-mile radius to consider leaving. It insisted the advice was given due to concern for their quality of life, not exposure to harmful levels of radiation. According to the public broadcaster NHK, self-defence force personnel in the evacuation zone said 30 people had yet to leave the 12-mile evacuation zone, and 10 had indicated they wanted to remain in their homes. Evacuees have been urged not to return to the area to collect belongings while the Fukushima plant remains unstable. Residents who return, even temporarily, would expose themselves to “great risk of radiation contamination”, Edano said. “It is very likely that the [12m] area is contaminated and there is a significant risk to health,” he added. Local authorities reported, however, that some people had already returned. Others forced out of their homes are coming to terms with the possibility that they may never be able to return. Even if they do, the many residents who depended on Tepco for employment accept that with the plant ruined, their chances of finding work in the area are close to nil. A large number of evacuees have already moved twice since the nuclear crisis began, and could be forced to move again if the situation worsens and the evacuation zone is expanded. “We’re assuming that in a worse-case scenario we might also be subject to evacuation,” Norio Hattori, a disaster official in Nihonmatsu, said, adding that he had sent his own daughter to Tokyo. Some of the refugees are beginning to accept that a vast area surrounding the Fukushima plant could be condemned as a nuclear wasteland. “If it had been an earthquake or a tsunami, we could have gone home again, but because it’s radiation, we can’t,” said Tokuko Sujimoto. Her home, in the village of Namie, was so close to the plant she heard the first reactor explosion on 12 March. Her husband had watched from the roof of their house as a cloud of smoke rose from the reactor, before they fled. Yoshimoto Nogi, who had a job at the Fukushima plant until he retired last summer, said he had no hopes of going home this year. “It’s going to take a year or two. It is not a question of months,” said Nogi. “Even if the nuclear plant is stabilised tomorrow, I don’t think the government is going to tell us it is safe to go back any time soon.” Japan disaster Japan Nuclear power Energy Justin McCurry Suzanne Goldenberg guardian.co.uk

Posted by on March 28, 2011. Filed under News, Politics, World News. You can follow any responses to this entry through the RSS 2.0. You can skip to the end and leave a response. Pinging is currently not allowed.