Japan may have lost race to save nuclear reactor
2011 03 30

From: guardian.co.uk


Highly radioactive water is now being detected outside the containment area at Fukushima, experts have warned.


Fukushima meltdown fears rise after radioactive core melts through vessel – but 'no danger of Chernobyl-style catastrophe'

The radioactive core in a reactor at the crippled Fukushima nuclear power plant appears to have melted through the bottom of its containment vessel and on to a concrete floor, experts say, raising fears of a major release of radiation at the site.

'Fukushima plutonium leak comparable to Chernobyl disaster'


Video from: RT

The warning follows an analysis by a leading US expert of radiation levels at the plant. Readings from reactor two at the site have been made public by the Japanese authorities and Tepco, the utility that operates it.

Richard Lahey, who was head of safety research for boiling-water reactors at General Electric when the company installed the units at Fukushima, told the Guardian workers at the site appeared to have "lost the race" to save the reactor, but said there was no danger of a Chernobyl-style catastrophe.

Workers have been pumping water into three reactors at the stricken plant in a desperate bid to keep the fuel rods from melting down, but the fuel is at least partially exposed in all the reactors.

At least part of the molten core, which includes melted fuel rods and zirconium alloy cladding, seemed to have sunk through the steel "lower head" of the pressure vessel around reactor two, Lahey said.

"The indications we have, from the reactor to radiation readings and the materials they are seeing, suggest that the core has melted through the bottom of the pressure vessel in unit two, and at least some of it is down on the floor of the drywell," Lahey said. "I hope I am wrong, but that is certainly what the evidence is pointing towards."

The major concern when molten fuel breaches a containment vessel is that it reacts with the concrete floor of the drywell underneath, releasing radioactive gases into the surrounding area. At Fukushima, the drywell has been flooded with seawater, which will cool any molten fuel that escapes from the reactor and reduce the amount of radioactive gas released.

Lahey said: "It won't come out as one big glob; it'll come out like lava, and that is good because it's easier to cool."

The drywell is surrounded by a secondary steel-and-concrete structure designed to keep radioactive material from escaping into the environment. But an earlier hydrogen explosion at the reactor may have damaged this.

"The reason we are concerned is that they are detecting water outside the containment area that is highly radioactive and it can only have come from the reactor core," Lahey added. "It's not going to be anything like Chernobyl, where it went up with a big fire and steam explosion, but it's not going to be good news for the environment."

The radiation level at a pool of water in the turbine room of reactor two was measured recently at 1,000 millisieverts per hour. At that level, workers could remain in the area for just 15 minutes, under current exposure guidelines.

A less serious core meltdown happened at the Three Mile Island nuclear plant in Pennsylvania in 1979. During that incident, engineers managed to cool the molten fuel before it penetrated the steel pressure vessel. The task is a race against time, because as the fuel melts it forms a blob that becomes increasingly difficult to cool.

In the light of the Fukushima crisis, Lahey said all countries with nuclear power stations should have "Swat teams" of nuclear reactor safety experts on standby to give swift advice to the authorities in times of emergency, with international groups co-ordinated by the International Atomic Energy Authority.

The warning came as the Japanese authorities were being urged to give clearer advice to the public about the safety of food and drinking water contaminated with radioactive substances from Fukushima.

Robert Peter Gale, a US medical researcher who was brought in by Soviet authorities after the Chernobyl disaster, in 1986, has met Japanese cabinet ministers to discuss establishing an independent committee charged with taking radiation data from the site and translating it into clear public health advice.

"What is fundamentally disturbing the public is reports of drinking water one day being above some limit, and then a day or two later it's suddenly safe to drink. People don't know if the first instance was alarmist or whether the second one was untrue," said Gale.

"My recommendation is they should consider establishing a small commission to independently convert the data into comprehensible units of risk for the public so people know what they are dealing with and can take sensible decisions," he added.

Source: guardian.co.uk



Related Articles


Latest News from our Front Page

6,000-Year-Old Temple with Possible Sacrificial Altars Discovered
2014 10 21
A 6,000-year-old temple holding humanlike figurines and sacrificed animal remains has been discovered within a massive prehistoric settlement in Ukraine. Built before writing was invented, the temple is about 60 by 20 meters (197 by 66 feet) in size. It was a "two-story building made of wood and clay surrounded by a galleried courtyard," the upper floor divided into five ...
What happened to Journalist Serena Shim? Assassinated? Find out what happened to Serena, Press TV director calls on Turkey
2014 10 21
Press TV news director Hamid Reza Emadi says the “suspicious death,” of the news channel’s correspondent in Turkey is a tragedy for “anyone who wants to get the truth.” Emadi made the remarks in an interview with Press TV on Sunday following Serena Shim’s death across the border from Syria’s Kurdish city of Kobani, where the ISIL terrorists and Kurdish fighters ...
Ancient Roman Nanotechnology Inspires Next-Generation Holograms for Information Storage
2014 10 21
The Lycurgus Cup, as it is known due to its depiction of a scene involving King Lycurgus of Thrace, is a 1,600-year-old jade green Roman chalice that changes colour depending on the direction of the light upon it. It baffled scientists ever since the glass chalice was acquired by the British Museum in the 1950s, as they could not work ...
Rapid Geomagnetic Reversal Possibility: Confirmed
2014 10 21
From the video: "The scientists who conducted the study are still unsure why the magnetic field is weakening, but one likely reason is the Earth’s magnetic poles are getting ready to flip, said Rune Floberghagen, the ESA’s Swarm mission manager. In fact, the data suggest magnetic north is moving toward Siberia." Tune into Red Ice Radio: Ben Davidson - Suspicious0bservers: Space Weather ...
Georgia Guide Stone 2014 cube stone removal
2014 10 21
From: Youtube: Was it all just a gag? it seems the cube stone just happens to be made out of the same Elberton granite that the rest of this morbid monument is made from.
More News »