Thursday, May 26, 2011

IAEA Knew Within Weeks of Japanese Earthquake that Reactors Had Melted Down ... Public Not Told for a Month and a Half



.
Did the Dimona Dozen murder the Fukushima 50?




 
As , reactors 1, 2 and 3 all melted down within hours of the Japanese earthquake.

On Monday, Mainchi Daily News provided an important tidbit:

A meltdown occurred at one of the reactors at the Fukushima No. 1 Nuclear Power Plant three and a half hours after its cooling system started malfunctioning, according to the result of a simulation using "severe accident" analyzing software developed by the Idaho National Laboratory.
Chris Allison [a former manager and technical leader at Idaho National Laboratory], who had actually developed the analysis and simulation software, reported the result to the International Atomic Energy Agency (IAEA) in late March. It was only May 15 when Tokyo Electric Power Co. (TEPCO) admitted for the first time that a meltdown had occurred at the No. 1 reactor at the Fukushima nuclear plant.
According to Allison's report obtained by the Mainichi, the simulation was based on basic data on light-water nuclear reactors at the Laguna Verde Nuclear Power Plant in Mexico that are about the same size as that of the No. 1, 2, and 3 reactors in Fukushima.
According to the simulation, the reactor core started melting about 50 minutes after the emergency core cooling system of the No. 1 reactor stopped functioning and the injection of water into the reactor pressure vessel came to a halt. About an hour and 20 minutes later, the control rod and pipes used to gauge neutrons started melting and falling onto the bottom of the pressure vessel. After about three hours and 20 minutes, most of the melted fuel had piled up on the bottom of the pressure vessel. At the four hour and 20 minute mark, the temperature of the bottom of the pressure vessel had risen to 1,642 degrees Celsius, close to the melting point for the stainless steel lining, probably damaging the pressure vessel.
In other words, the IAEA knew in late March that there was a meltdown. The IAEA informs all of its member states of important nuclear developments.
Government agencies sat on this information, and the world didn't learn the truth until the operator of the stricken reactors itself made the announcement a month and a half later.
This is not entirely surprising given that governments have been covering up nuclear meltdowns for fifty years to protect the nuclear industry.

H/t: Ex-Skf

Everyone who has any inkling of the nuclear process knew. especially after they saw the video of the explosion, with the roof of the building and the top of the containment vessel falling from the sky.only people who didn't want to know remained in denial. there seems to be a lot of that going around lately....



Monday, May 23, 2011

Two Nuclear Reactors Were Damaged by the Earthquake, BEFORE the Tsunami Hit ... and the Entire Nuclear Reactor Design Is Flawed ....

 
 
 
 
Two Nuclear Reactors Were Damaged by the Earthquake, BEFORE the Tsunami Hit ... and the Entire Nuclear Reactor Design Is Flawed ....
 


Bloomberg reported last week:
A radiation alarm went off at Tokyo Electric Power Co.’s Fukushima nuclear power plant before the tsunami hit on March 11, suggesting that contrary to earlier assumptions the reactors were damaged by the earthquake that spawned the wall of water.
A monitoring post on the perimeter of the plant about 1.5 kilometers (1 mile) from the No. 1 reactor went off at 3:29 p.m., minutes before the station was overwhelmed by the tsunami that knocked out backup power that kept reactor cooling systems running, according to documents supplied by the company. The monitor was set to go off at high levels of radiation, an official said.
Nuclear expert Arnie Gundersen just confirmed that some of the Japanese nuclear reactors were severely damaged even before the tsunami hit.
Specifically, Gundersen reports that the containment vessel at Fukushima 1 started leaking and melting down before the tsunami hit. Similarly, Gundersen notes that the fuel pool at reactor 4 cracked and started leaking after the earthquake and before the water hit.
Remember that Japanese seismologists had warned for years that Japan's reactors were extremely vulnerable to earthquakes, with one top seismologist noting:
It's like a kamikaze terrorist wrapped in bombs just waiting to explode.
Gundersen also points out that Florida's nuclear reactors are vulnerable to tidal surges from hurricanes, and California's reactors vulnerable to tidal surges caused by earthquakes.
And he notes that the attempt to release pressure at Fukushima failed 3 out of 3 times: 100% failure rate.

Gundersen notes that this shows that the entire design of these old-fashioned nuclear reactors is a failure.

Finally, Gundersen says - I've
repeatedly noted - that conditions are in many ways even more precarious in the U.S. than in Japan.
 

Monday, May 16, 2011

TEPCO Admits Cores Damaged at Three Reactors...

TEPCO Admits Cores Damaged at Three Reactors...
 
 
 
 
 
By MITSURU OBE
TOKYO—Substantial damage to the fuel cores at two additional reactors of Japan’s Fukushima Daiichi nuclear complex has taken place, operator Tokyo Electric Power Co. said Sunday, further complicating the already daunting task of bringing them to a safe shutdown while avoiding the release of high levels of radioactivity. The revelation followed an acknowledgment on Thursday that a similar meltdown of the core took place at unit No. 1.
Junichi Matsumoto, an official of Tokyo Electric Power Co. listens to questions during a press conference regarding the meltdown of Fukushima Daiichi nuclear power plant at the company headquarters in Tokyo, Japan, May 13, 2011.
 
Workers also found that the No. 1 unit’s reactor building is flooded in the basement, reinforcing the suspicion that the containment vessel is damaged and leaking highly radioactive water.
The revelations are likely to force an overhaul of the six- to nine-month blueprint for bringing the reactors to a safe shutdown stage and end the release of radioactive materials. The original plan, announced in mid-April, was due to be revised May 17.

The operator, known as Tepco, said the No. 1 unit lost its reactor core 16 hours after the plant was struck by a magnitude-9 earthquake and a giant tsunami on the afternoon of March 11.
The pressure vessel a cylindrical steel container that holds nuclear fuel, “is likely to be damaged and leaking water at units Nos. 2 and 3,” said Junichi Matsumoto, Tepco spokesman on nuclear issues, in a news briefing Sunday.

He also said there could be far less cooling water in the pressure vessels of Nos. 2 and 3, indicating there are holes at the bottom of these vessels, with thousands of tons of water pumped into these reactors mostly leaking out.

Tepco found the basement of the unit No. 1 reactor building flooded with 4.2 meters of water. It isn’t clear where the water came from, but leaks are suspected in pipes running in and out of the containment vessel, a beaker-shaped steel structure that holds the pressure vessel.
The water flooding the basement is believed to be highly radioactive. Workers were unable to observe the flooding situation because of strong radiation coming out of the water, Tepco said.
A survey conducted by an unmanned robot Friday found radiation levels of 1,000 to 2,000 millisieverts per hour in some parts of the ground level of unit No. 1, a level that would be highly dangerous for any worker nearby. Japan has placed an annual allowable dosage limit of 250 millisieverts for workers.

The high level of radioactivity means even more challenges for Tepco’s bid to set up a continuous cooling system that won’t threaten radiation leaks into the environment.
Tepco separately released its analysis on the timeline of the meltdown at unit No. 1. According to the analysis, the reactor core, or the nuclear fuel, was exposed to the air within five hours after the plant was struck by the earthquake. The temperature inside the core reached 2,800 degrees Celsius in six hours, causing the fuel pellets to melt away rapidly.

Within 16 hours, the reactor core melted, dropped to the bottom of the pressure vessel and created a hole there. By then, an operation to pump water into the reactor was under way. This prevented the worst-case scenario, in which the overheating fuel would melt its way through the vessels and discharge large volumes of radiation outside.
The nuclear industry lacks a technical definition for a full meltdown, but the term is generally understood to mean that radioactive fuel has breached containment measures, resulting in a massive release of fuel.

“Without the injection of water [by fire trucks], a more disastrous event could have ensued,” said Mr. Matsumoto.
Tepco also released its analysis of a hydrogen explosion that occurred at unit No. 4, despite the fact that the unit was in maintenance and that nuclear fuel stored in the storage pool was largely intact.

According to Tepco, hyrogen produced in the overheating of the reactor core at unit 3 flowed through a gas-treatment line and entered unit No. 4 because of a breakdown of valves. Hydrogen leaked from ducts in the second, third and fourth floors of the reactor building at unit No. 4 and ignited a massive explosion.


Saturday, May 14, 2011

Tepco Has Been "Going Round and Round in Circles" at Fukushima Using the Wrong Approach


Reactor 1

Tepco says that the fuel rods at Fukushima reactor 1 are exposed. As Bloomberg notes:
Tokyo Electric Power Co. said fuel rods are fully exposed in the No. 1 reactor at its stricken Fukushima Dai-Ichi nuclear plant, setting back the utility’s plan to resolve the crisis.
The water level is 1 meter (3.3 feet) below the base of the fuel assembly, Junichi Matsumoto, a general manager at the utility known as Tepco, told reporters at a briefing in Tokyo. Melted fuel has dropped to the bottom of the pressure vessel and is still being cooled, Matsumoto said. The company doesn’t know how long the rods have been exposed, he said.
***
It’s unlikely the situation has worsened with the discovery the rods are exposed because they’ve probably been out of the water since shortly after the crisis started, Narabayashi said.
Indian Express notes:
TEPCO today said new measurements taken this week, after workers in protective suits fixed gauges in the badly-hit reactor one building, indicated that water pumped into the pressure vessel had quickly leaked out.
The Telegraph points out:
One of the reactors at the crippled Fukushima Daiichi power plant did suffer a nuclear meltdown, Japanese officials admitted for the first time today, describing a pool of molten fuel at the bottom of the reactor’s containment vessel.

***

The company is worried that the molten pool of radioactive fuel may have burned a hole through the bottom of the containment vessel, causing water to leak.
Bloomberg quotes a top nuclear expert as saying that Tepco has been going about it all wrong:
“I’ve been saying from the beginning the water tomb plan won’t work,” said Tadashi Narabayashi, a professor of nuclear engineering at Hokkaido University. “Tepco must work on a water circulation cooling system as soon as possible. They’ve been going round and round in circles and now realize this is what they need to do.”
Even Tepco is admitting they must change course:
“The plan needs to be revised,” Matsumoto said. “We can’t deny the possibility that a hole in the pressure vessel caused water to leak.”
Reactor 2 As discussed below, nuclear engineer Arnie Gundersen has repeatedly said that nuclear reactions likely occurred long after the tsunami hit.
Now, as MIT's Technology Review notes:
Tetsuo Matsui at the University of Tokyo, says the limited data from Fukushima indicates that nuclear chain reactions must have reignited at Fuksuhima up to 12 days after the accident.

***
He says the ratios from drains at reactors 1 and 3 at Fukushima are consistent with the nuclear reactions having terminated at the time of the earthquake.
However, the data from the drain near reactor 2 and from the cooling pond at reactor 4, where spent fuel rods are stored, indicate that the reactions must have been burning much later.
***
So things in reactor 2 must have been extremely dangerous right up to the end of March.
Reactor 3
Nuclear expert Arnie Gundersen suspects that the huge explosion at reactor number 3 was a nuclear explosion, where the initial hydrogen explosion triggered a "prompt criticality" which spewed radiation high into the air:

Gundersen Postulates Unit 3 Explosion May Have Been Prompt Criticality in Fuel Pool from Fairewinds Associates on Vimeo.
As WSWS notes:
Arnie Gundersen of Fairewinds Associates, who has spent 39 years working in the nuclear industry and now acts as an expert witness, has suggested that the explosion in Number 3 building at Fukushima on March 14 may have been more serious than has so far been admitted.
Gundersen argues that an initial hydrogen explosion caused a prompt criticality in the spent-fuel rod pool at the top of the Number 3 reactor building. Prompt criticality is the term used in the nuclear industry for an exponential increase in the number of fission events. That is to say a runaway nuclear chain reaction may have taken place in the spent fuel rods.
Gundersen postulates that the upward vector, the upward thrust, from the explosion in Building 3 may have been sufficient to carry radioactive isotopes from the fuel rods into the atmosphere and to disperse them over many thousands of miles. He points out that uranium has been found on Hawaii, americium has been found in New England and plutonium dust has been found on the Fukushima site. These latter elements are transuranic, i.e. heavier than uranium, and indicate that nuclear fuel was volatilized at Fukushima.
Reactor 4
The building housing reactor 4 is leaning, and Tepco is attempting to shore it up so it doesn't fall over:
http://www.youtube.com/watch?v=Dxbm7iJTT8U&feature=player_embedded
 

Very high radiation levels were showing up in the containment vessel of reactor 4, even though that reactor was supposedly shut down before the earthquake. Since I posted that article, the Japan's nuclear agency has removed all readings for reactor 4.