2011-03-14, 06:54 PM
Kalovale Wrote:And that makes "40 years is too old" a valid fact because?Well, why dont you look up the information for the life expectancy of the plant? Maybe ask ABC where they get their facts from and why they say it should have been taken down years ago.
Why even live there at all? Why did UAEA allow the Japanese to, or at least not disallow them to, build the plants in the first place?
Also, it does not make them any more incompetent when a warning has been issued priorly, why you ask? Because it's pineappleing common sense that Japan is on a hot stove, they don't need warning to know that they live in "a volatile earthquake zone" and that putting a bomb on it is kinda a bad idea. I can give any of those warnings too, if you want.
Of course, I'm not asking you to do anything I'm not doing myself
And actually read a damn article. The Japanese government was warned that their prevention systems were too lax, that a disaster was immient.
Quote:A JAPANESE expert on nuclear safety warned more than three years ago that the policy of building large numbers of reactors in the middle of a volatile earthquake zone could lead to catastrophe.
As the authorities battled to avert a meltdown at the Fukushima plant, it emerged that a senior figure in Japan's nuclear community resigned in protest from a safety panel saying guidelines to protect atomic power plants from earthquake damage were too lax.
Ishibashi Katsuhiko, a professor at Kobe university, said seismic guidelines brought in to protect Japan's 55 reactors in 2006 were "still seriously flawed".
He pointed out that big quakes had taken place in "close proximity" to three nuclear power plants in Japan from 2005 to 2007. In each case, the ground motion caused by the quake was stronger than that for which the plants had been designed.
A tremor at the Kashiwazaki Kariwa plant, about 300km across the main island from Fukushima, had experienced a tremor with ground motion of 993 gal (a measure of ground movement), far beyond its design value of 450 gal.
"Not only are the new design guidelines defective but the system to enforce them is in a shambles," wrote Professor Katsuhiko after his resignation. He said it was just a matter of luck that the epicentre of each earthquake had not been nearer.
In an article in 2007 explaining his resignation, Professor Katsuhiko said almost all of the Japanese archipelago had entered a period of brisk seismic activity since the Kobe earthquake of 1995.
"Unless radical steps are taken now to reduce the vulnerability of nuclear power plants to earthquakes, Japan could experience a true nuclear catastrophe in the near future," he wrote.
Scientists say early assessments indicate that Japan should not fear a nuclear disaster on the scale of Chernobyl in 1986, where both the pressure vessel housing the reactor and the building containing it were breached in an explosion.
Robin Grimes, director of the Nuclear Energy Centre at Imperial College London, said the Japanese authorities had reported that the steel containment walls housing the reactor's core had not been breached, even though an explosion has blown the roof off the power plant.
"That's really good news. It means no nuclear fuel will have leaked from the reactor and scattered around the surrounding area as happened with Chernobyl," he said.
Mr Grimes said the incident was more like Three Mile Island in America in 1979, where contaminated coolant leaked into the reactor building after an accident that partly melted the reactor's core.
"There could still be significant damage to the core of the reactor and we know that caused sufficient concerns that led to the nuclear program stopping in the US," he said.
Experts said pictures of mist above the plant indicated that engineers may have deliberately released gas from the core to prevent hydrogen accumulating and blowing up the steel core. By contrast, vast radioactive clouds spewed out of Chernobyl, turning the area of Ukraine into a ghost zone.
Timothy Abram, professor of nuclear fuel technology at Manchester University, said any damage to the reactor's core should become evident from monitoring radioactivity.
"The thing they will be looking for is whether there is any evidence of the fuel degrading. If the fuel is substantially intact, there will be a much, much lower release of radioactivity and the explosion that's happened might just be due to a build-up of steam in the reactor circuit."
The Sunday Times "
Of course we can say that it is good that there are differences from chernobyl. But the japanese ignored the warnings and the clear and present threat to their country.
Edit: Not the best source, but its something:
PWR's and BWR's have been licensed for 40 year life, but subject to possible repair work if there are doubts about integrity, especially of the primary pressure circuit. Only two plants have operated more than 30 years in practice. A number have been shutdown as uneconomic to do necessary repairs.
Read more: http://wiki.answers.com/Q/How_long_does_...z1GcM9T7M0
If I'm correct this is by US standards, and this would mean that full 40 years has not been sufficiently tested and that most power plants would stop operating long before the 40 year mark