TOKYO - Japanese authorities said Sunday that efforts to restart the system for cooling a reactors damaged by the earthquake of Friday had failed, while officials has difficulty controlling several other damaged reactors.
The Fukushima Daiichi nuclear power workers have not found a way of stabilising the overheated reactors and feared the possibility of partial nuclear fusion, which could potentially cause an another release of radioactive material, high Government of the Japan spokesmansaid Sunday. Engineers have difficulty, in particular, with two units at the nuclear facility - which lost lining outer containment Saturday in an explosion.
During this time, officials declared a State of emergency at a nuclear power plant in Onagawa, where excessive radiation levels have been reported.
Secretary General of the Government Yukio Edano said that a similar explosion could soon occur in unit 3 of Fukushima Daiichi, the result of the levels of hydrogen are on the rise in ship of reactor unit in the ultimate strives to keep the immersed in water fuel rods. Already, traces of radioactive material have a leak of reactor No. 3, Edano said.
"At the risk of further raise the public interest, we cannot rule out the possibility of an explosion,"Said Edano.""
But Edano also insisted that an explosion would have no impact on human health. Based on initial findings of the Government and the Japan nuclear agency, the explosion Saturday in unit 1 made step damage the reactor building, and the Government stated that the unit 3 reactor vessel would also withstand an explosion. The vessels of the No. 3 and no. 1 reactor is to be flooded with sea water and boron in an attempt to urgently to keep cool units after the lost its main power plant and a backup system failed.
Although the unit is being filled with water, gauge inside does not record the rise of the level, Edano said. It is not an explanation.
"If the cooling system is not maintained, there is good chance that the kernel could start melting down," said Masahi Gota, a former engineer of Toshiba, who participated in the design of the vessel containment for these reactors.
Richard Lester, co-Chair of the engineering in the MIT and the Department of Nuclear Science, said: "the most important task that operators have - and have had past hours 36 - is to keep fuel in the reactor cover."immersed in water. If they succeed in doing that, keeping the bars of fuel covered in water, the likelihood of damage to the fuel is low. If they cannot be covered with water, fuel and then you have the possibility of melting. ?
Some 170,000 people were evacuated within a radius of 12 miles of the plant. They join more than 450,000 other evacuees from other regions of the Earth and the tsunami earthquake-affected. A spokesman for the Japan nuclear agency said that up to 160 people may have been exposed to radiation and have been tested in a hospital to determine if levels were dangerous.
"Only the most serious danger justify an evacuation at a time", said Peter Bradford, former Commissioner of the Nuclear Regulatory Commission of the United States.
Edano said officials were acting on the assumption that a collapse could be being Fukushima Daiichi unit 3, and that he was "very possible" a collapse was current in its reactor unit 1, where an explosion destroyed a building a day earlier.
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