Thursday, June 9, 2011

"Japan Admits “Worse Than Meltdown” - Nuclear “Melt-Through” In 3 Reactors"

"Japan Admits “Worse Than Meltdown” - Nuclear “Melt-Through” In 3 Reactors"
by Washington’s Blog/Alexander Higgins

"The Telegraph reports today: The nuclear fuel in three of the reactors at the Fukushima Dai-Ichi nuclear plant has melted through the base of the pressure vessels and is pooling in the outer containment vessels, according to a report by the Japanese government. The findings of the report, which has been given to the International Atomic Energy Agency, were revealed by the Yomiuri newspaper, which described a "melt-through" as being "far worse than a core meltdown" and "the worst possibility in a nuclear accident."
Click image for larger size.
The pressure vessel of the No. 1 reactor is now believed to have suffered damage just five hours after the March 11 earthquake and tsunami, contrary to an estimation released by Tepco, which estimated the failure at 15 hours later. Melt-downs of the fuel in the No. 2 and No. 3 reactors followed over the following days with the molten fuel collecting at the bottom of the pressure vessels before burning through and into the external steel containment vessels. "The recovery effort at the plant is likely to be more difficult as they will not be able to use their previous plan to contain the fuel," Yoshiaki Oka, a professor of nuclear science at Tokyo's Waseda University told The Daily Telegraph. "So it may take longer and be more difficult, but it is something they have to do."

Other portions of the Telegraph article underplay the severity of the crisis, such as: "The fuel appears to be stable at present as it is being cooled by water pumped into the vessels, although it will complicate the emergency recovery plan put forward by the government." But we now know that this happened at the very beginning of the accident, so I see no particular additional affects on human health, he said.

Alexander Higgins notes: "The Telegraph report once again echoes statement from TEPCO that the fuel at the plant is now being cooled and that plant is stable. However, we have heard the same exact statements from TEPCO day after day for almost three months now. We heard it when there was no meltdown. and an were assured the rods were stable so the risk of meltdown was little to none. The media printed the statements.
When we were told that there was only a partial nuclear meltdown under way and there is no comparison between Fukushima and Chernobyl. Again, TEPCO and the media told use there was no danger because the fuel rods were stable and being cooled. Then were found out this was in fact a level 7 incident on par with Chernobyl and were reassured the plant and fuel rods were stable. Then they reveal a full meltdown occurred at 3 reactors, and the media again reported the fuel rods were stable and being cooled. Now even with news that the nuclear lava inside the reactor has melted through the base of 3 reactors they once again print the same lies again that the cool rods are being effectively cooled and are in stable condition? Should we believe them this time after 3 months of lies? The media is also still reporting that there is no risk to human health in Japan. What a joke. Does anyone seriously believe these lies?"

Indeed, as NHK reported Saturday: "The operator of the damaged Fukushima Daiichi nuclear plant says steam was observed coming out of the floor of the No.1 reactor building, and extremely high radiation was detected in the vicinity. TEPCO said it found that steam was rising from a crevice in the floor, and that extremely high radiation of 3,000 to 4,000 millisieverts per hour was measured around the area. The radiation is believed to be the highest detected in the air at the plant. TEPCO says the steam is likely coming from water at a temperature of 50 degrees Celsius that has accumulated in the basement of the reactor building."

And Japan Times reports today: "The government should consider evacuating children and pregnant women from a wider area around the Fukushima No. 1 power plant because radiation levels remain high even outside the 20-km no-go zone, Kumi Naidoo, executive director of Greenpeace International, said Thursday in Tokyo. Naidoo's team of radiology experts found hot spots that had a maximum hourly reading of 45 microsieverts of radiation alongside a school zone.

During the news conference, Jan Beranek, an expert on radiology from Greenpeace International who joined Naidoo's trip to Fukushima, recommended that the government widen the evacuation zone to at least 60 or 70 km from the power plant. He said there were parks and public spaces where the level of radiation activity hit 9 microsieverts per hour. Even some nursery schools that have already undergone a decontamination process had a relatively high reading of 0.5 microsievert per hour, he said. That would translate into an annual exposure of 5 millisieverts, which was the evacuation threshold for Chernobyl, Beranek said. The government recommends a maximum intake of 1 millisievert a year during normal times, but raises that to 20 millisieverts in times of a nuclear accident.
Beranek recommended that people in Fukushima residing in areas with high levels of radiation wear masks and remain inside their homes. Radiation from some kinds of particles "is not something that goes away in weeks or months," he said, explaining that some chemical elements can be absorbed into organs and bones. While expressing concern that the level of decontamination "hasn't been adequate" in Fukushima, Naidoo also said he fears that people there haven't received sufficient information from the central government. Pointing out that many children living near areas with high levels of radiation are playing outdoors without proper masks, he criticized the government for being "too slow" in explaining the risks of exposure."
A comment: I'm not going to bother with citations in this comment, they're all included in many posts on this blog. So, what do we know? Each reactor contained 16,000 fuel rods in the active core. Above each containment vessel there was a storage facility containing approximately 40,000 spent but still extremely radioactive fuel rods, which we must assume have fallen into the molten core below during hydrogen gas explosions that destroyed the buildings. Approximately 56,000 fuel rods in total at each reactor, "burning" at 5,200 degrees F. These molten slag piles have now breached the bottoms of the containment vessels, with nothing to stop their further progress deeper into the earth. Since the Fukushima Nuclear plant is on the coastline of the Pacific Ocean there is a virtually limitless supply of groundwater which the molten slags will eventually encounter. What is produced when water encounters a temperature of 5,200 degrees F? Steam. In this case, highly radioactive steam, rising high into the atmosphere, where the jet stream and wind currents will carry it literally around the world. Draw your own conclusions as to what this all means... - CP

No comments:

Post a Comment