4:00 PM, Mar. 13, 2011
IWAKI, Japan — A partial meltdown was likely under way at a second nuclear reactor, a top Japanese official said early today, as authorities frantically tried to prevent a similar threat from nearby unit following a catastrophic earthquake and tsunami.
Some 170,000 people have been ordered to evacuate the area covering a radius of 12 miles around the plant in Fukushima near Iwaki. A meltdown refers to a very serious collapse of a power plant's systems and its ability to manage temperatures. A complete meltdown would release uranium and dangerous byproducts into the environment that can pose serious health risks.
Oil tar lie in the other side of the river bank from burning oil refinery following a massive tsunami triggered by March 11 earthquake in Tagajo, near Sendai, northern Japan on Sunday. / Associated Press
Japan dealt with the nuclear threat as it struggled to determine the scope of the twin disasters Friday, when an 8.9-magnitude earthquake, the most powerful in its recorded history, was followed by a tsunami that ravaged its northeastern coast with breathtaking speed and power.
The official count of the dead was 763, but the government said the figure could far exceed 1,000. Media reports said some 10,000 people were missing or unaccounted for.
The quake and tsunami damaged three reactors at the Fukushima Dai-ichi nuclear plant, which lost their cooling functions necessary to keep the fuel rods functioning properly. At first the Unit 1 reactor was in trouble with an explosion destroying the walls of the room in which it is placed.
Later, Unit 3 also began to experience problems.
Chief Cabinet Secretary Yukio Edano said operators released slightly radioactive air from Unit 3, while injecting water into it as an effort to reduce pressure and temperature to save the reactor from a possible meltdown.
Still, a partial meltdown in the unit is "highly possible," he told reporters.
"Because it's inside the reactor, we cannot directly check it but we are taking measures on the assumption of the possible partial meltdown," he said.
Edano said radiation levels briefly rose above legal limits, but that it has since declined significantly. Also, fuel rods were exposed briefly, he said, indicating that coolant water didn't cover the rods for some time. That would contribute further to raising the temperature in the reactor vessel.
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Japan faces escalating nuke threat, meltdowns may occur
English.news.cn 2011-03-13 14:31:45
The No. 3 reactor at the Fukushima No. 1 nuclear power plant is seen in this still image taken from NHK news program on March 13, 2011. Tokyo Electric Power Co., the utility supplier, notified the government early Sunday morning that the No. 3 reactor at the No. 1 Fukushima plant had lost the ability to cool the reactor core. The reactor is now in the process of releasing radioactive steam, according to top government spokesman Yukio Edano. (Xinhua/NHK)
TOKYO, March 13 (Xinhua) -- Japan is facing an escalating nuclear threat on Sunday as the country's top government spokesman warned that radioactive meltdowns may have occurred in two reactors of the Fukushima nuclear power plant.
"We are acting on the assumption that there is a high possibility that one has occurred" in the No. 1 reactor of the quake-hit plant, Chief Cabinet Secretary Yukio Edano told a press conference on Sunday while being asked whether or not meltdowns had occurred.
"As for the No. 3 reactor, we are acting on the assumption that it is possible," he said.
The latest reports of Japan's Sankei Shimbun said that pressure has been successfully released at the No. 3 reactor of the Fukushima No. 1 nuclear plant following the injection of fresh water.
Tokyo Electric Power Co.(TEPOC), operator and owner of Fukushima nuclear plants, said early on Sunday that a sixth reactor at the nuclear power plants has lost its ability to cool the reactor core since Friday's quake.
The No. 3 reactor at Fukushima No. 1 nuclear power plant lost the cooling function after No. 1 and No. 2 reactors at the No. 1 plant and No. 1, No. 2 and No. 4 at the No. 2 plant had suffered the same trouble.
At an emergency press conference early Sunday, Edano said the reactor is releasing radioactive steam after the malfunction occurred.
An explosion occurred at the Fukushima No. 1 nuclear power plant Saturday, destroying the roof and the walls of the building of the No. 1 reactor's outer container.
Four people were injured at the power plant, but radiation levels dropped quickly after surging for a while following the blast.
The top government spokesman warned that 114 people are still staying within a 10-km radius of Fukushima No.1 nuclear power plants and 180,000 in the 20-km evacuation zone.
All inhabitants have been evacuated from a 3-km radius of the No. 2 plant, and authorities have begun evacuating more than 30,000 from a 10-km zone around the plant, he added.
On Saturday, authorities expanded the evacuation zone from a 10-km radius for the Fukushima nuclear plants to a 20-km radius.
Kyodo News reported Sunday that 19 more people were found to have been exposed to radiation, in addition to the three exposure cases recorded Saturday,
Tokyo Electric Power Co. has notified Japan's nuclear safety agency that the radiation level at the Fukushima No. 1 nuclear power plant has exceeded the legal limit.
The Japanese authorities on Sunday upgraded the magnitude of the earthquake which hit the country's northeastern and eastern regions Friday to 9.0 from 8.8, Kyodo News reported, citing the Japan Meteorological Agency.
So far, the number of people who have died or remained unaccounted for after the quake have exceeded 2,000, the police said. The official death toll was around 700, Kyodo News said.
In Fukushima Prefecture alone, 1,167 were unaccounted for and well over 600 corpses had been found in both Fukushima and Miyazaki prefectures, said the report.
There are also tens of thousands of people that local governments have been unable to contact, police and local officials said.
Japanese Defense Minister Toshimi Kitazawa said Sunday that Prime Minister Naoto Kan has instructed the defense ministry to increase the size of Self-Defense Forces for quake relief operations from 50,000 to 100,000 troops.
While the country continues to grapple with the widespread damage from the massive earthquake, countries across the world have also offered a helping hand to it.
A total of 50 nations and regions have promised to provide with relief support, and offers from over 70 specialist rescue services from around the globe have been received by Japan.
A 15-member Chinese rescue team arrived at Tokyo's Haneda Airport Sunday for quake relief operations.
The Chinese International Search and Rescue Team (CISAR) brought with them 4 tons of materials and equipment for search and rescue, power supply and telecommunication.
The rescuers will immediately head for quake-hit areas to search for survivors from Friday's great earthquake and ensuing tsunami.
Editor: Wang Yan
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