.
_________________________________________________________________________________
Greenpeace Statement on TEPCO admission of full meltdown and reactor core breach at Fukushima-Daiichi
Tokyo, Japan, 16 May, 2011 – Greenpeace today criticised TEPCO and the Japanese government for continuing to underplay the seriousness of the Fukushima Daiichi nuclear crisis, after TEPCO yesterday admitted that a partial meltdown of the reactor 1 core at the Fukushima Daiichi nuclear plant occurred a mere five hours after the tragic March 11 earthquake and tsunami, followed by a full meltdown within 16 hours.
The environmental organisation says that TEPCO’s admission – that with temperatures reaching 2,800°C, melted fuel dropped and accumulated at the bottom of the reactor pressure vessel, which was the breached, causing radiation to leak from the core and to spread via cooling water to the ground and ocean – clearly shows that there are significant risks to the marine ecosystem along the Fukushima coast.
“That it has taken TEPCO more than two months to confirm that a full meltdown took place at Fukushima demonstrates the nuclear industry’s utter failure to deal with the severity of the crisis or the risks involved in nuclear power,” said Jan Beránek, Greenpeace International Nuclear Campaign Leader. “TEPCO should have known that water pumped into reactor vessel 1 would become highly contaminated – it is appalling that company did not do more to prevent massive volumes of contaminated water being released into the ocean, spreading long-lived radioactive contamination along Japan’s East coast.”
“The nuclear industry has claimed situations like Fukushima could not arise with this type of reactor, due to lessons learned in the past. It has taken far too long for Japan’s authorities to admit that they were wrong,” said Beránek. “This has major implications to all previous assumptions about nuclear safety, and it is clear that the public should not put their faith in the nuclear industry to protect their health and safety.”
“TEPCO must immediately make public any other information about the state of the other reactors at Fukushima.”
No data or analysis has been provided on the meltdowns that have probably taken place in units 2 and 3. Those two reactors are significantly larger than unit 1 and contain almost double amount of nuclear material.
_________________________________________________________________________
TEPCO admits nuclear meltdown occurred at Fukushima reactor 16 hours after quake
___________________________________________________________________________________
Tokyo Electric Power Co. (TEPCO) admitted for the first time on May 15 that most of the fuel in one of its nuclear reactors at the Fukushima No. 1 Nuclear Power Plant had melted only about 16 hours after the March 11 earthquake struck a wide swath of northeastern Japan and triggered a devastating tsunami.
According to TEPCO, the operator of the crippled nuclear power plant, the emergency condenser designed to cool the steam inside the pressure vessel of the No. 1 reactor was working properly shortly after the magnitude-9.0 earthquake, but it lost its functions around 3:30 p.m. on March 11 when tsunami waves hit the reactor.
Based on provisional analysis of data on the reactor, the utility concluded that the water level in the pressure vessel began to drop rapidly immediately after the tsunami, and the top of the fuel began to be exposed above the water around 6 p.m. Around 7:30 p.m., the fuel was fully exposed above the water surface and overheated for more than 10 hours. At about 9 p.m., the temperature in the reactor core rose to 2,800 degrees Celsius, the melting point for fuel. At approximately 7:50 p.m., the upper part of the fuel started melting, and at around 6:50 a.m. on March 12, a meltdown occurred.
On the reason why it took over two months after the earthquake to reveal the information, TEPCO said it had only been able to start obtaining detailed data on the temperature and pressure in the reactor for analysis in early May.
Junichiro Matsumoto, a senior TEPCO official, said, "Because there is similar damage to the fuel rods at the No. 2 and 3 reactors, the bottoms of their pressure vessels could also have been damaged." He said the utility would carry out similar analysis on the two reactors.
Hiroaki Koide, professor of nuclear safety engineering at Kyoto University, was critical of TEPCO.
"They could have assumed that when the loss of power made it impossible to cool down the reactor, it would soon lead to a meltdown of the core. TEPCO's persistent explanation that the damage to the fuel had been limited turned out to be wrong," he said.
According to TEPCO, the operator of the crippled nuclear power plant, the emergency condenser designed to cool the steam inside the pressure vessel of the No. 1 reactor was working properly shortly after the magnitude-9.0 earthquake, but it lost its functions around 3:30 p.m. on March 11 when tsunami waves hit the reactor.
Based on provisional analysis of data on the reactor, the utility concluded that the water level in the pressure vessel began to drop rapidly immediately after the tsunami, and the top of the fuel began to be exposed above the water around 6 p.m. Around 7:30 p.m., the fuel was fully exposed above the water surface and overheated for more than 10 hours. At about 9 p.m., the temperature in the reactor core rose to 2,800 degrees Celsius, the melting point for fuel. At approximately 7:50 p.m., the upper part of the fuel started melting, and at around 6:50 a.m. on March 12, a meltdown occurred.
On the reason why it took over two months after the earthquake to reveal the information, TEPCO said it had only been able to start obtaining detailed data on the temperature and pressure in the reactor for analysis in early May.
Junichiro Matsumoto, a senior TEPCO official, said, "Because there is similar damage to the fuel rods at the No. 2 and 3 reactors, the bottoms of their pressure vessels could also have been damaged." He said the utility would carry out similar analysis on the two reactors.
Hiroaki Koide, professor of nuclear safety engineering at Kyoto University, was critical of TEPCO.
"They could have assumed that when the loss of power made it impossible to cool down the reactor, it would soon lead to a meltdown of the core. TEPCO's persistent explanation that the damage to the fuel had been limited turned out to be wrong," he said.
Click here for the original Japanese story(Mainichi Japan) May 16, 2011
___________________________________________ _____________________________________ . .
Donate To Keep This Site Alive
______________________________________________________ ___________________________ . . . . _____________________________________________________________________________
No comments:
Post a Comment