Nuclear emergency declared at quake-damaged reactor

[googlegoogle]

http://www.usatoday.com/news/world/2...reactors_N.htm

[Dave Lane]

Originally Posted by Donger

Well, it seems like TEPCO is now presuming that at least one of the reactors sustained a vessel breach. That's never a good thing, but at least they prevented a full melt.

No a vessel breach in conjunction with a full meltdown would be really bad. Major cleanup issues. Probably have to seal it in concrete for awhile.

[Saulbadguy]

Originally Posted by teedubya

Yeah, Harassed, by ONE neg rep each. heh. Pussies. Donger got it twice though. I think I will harass him, since he is crying about it.

Not a patented SaulBadGuy harassment by any means.

EDIT: now you've all gotten it twice. I'm an equal opportunity offender.

My victims can attest to the fact that I leave my negative reps blank, or put nonsensical things in them - like "poopburgers".

[teedubya]

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.

http://mdn.mainichi.jp/mdnnews/news/...na028000c.html

[Donger]

Originally Posted by teedubya

"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.

Unless I missed something, a partial melt was assumed by everyone who knows what they are talking about.

[veist]

Originally Posted by teedubya

Whew. Everything is all better. Fox News says so.

Oh wait...

http://www.yomiuri.co.jp/science/new...htm?from=main1

TEPCO 14 unveiled a new image inside the reactor building of Fukushima Daiichi Nuclear Power Station Unit 1 was taken by remote-controlled robots and workers.

　Been published, and was taken near the southeast side of double doors on 13 remote-controlled robot, such as the northwest elevator hall 09 workers were taken, the image of five locations.

　The southwest building "transfer port big" around the scattered debris of the large expected impact of hydrogen explosion, near the elevator hall of the northwest, 吹Ki飛Bi the elevator door to further shape the elevator shaft like a tunnel square that the state is reflected.

　Double doors near the southeast entrance of the robot, a high dose was recorded 2000 mm per hour Sv radiation measurements, the scattering state is not reflected in particular. TEPCO is the result of high concentrations of polluted water flowed in the pipe near this location are expected to record high doses.

( 12:22 minutes May 14, 2011 Yomiuri Shimbun)

That's 2 SV an hour, folks.

Can you at least come up with a source that isn't bad machine translation that leaves some serious ambiguity as to what is trying to be conveyed?

[Donger]

Originally Posted by veist

Can you at least come up with a source that isn't bad machine translation that leaves some serious ambiguity as to what is trying to be conveyed?

[loochy]

Originally Posted by teedubya

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.

http://mdn.mainichi.jp/mdnnews/news/...na028000c.html

Just stick to posting pictures of Eva Longoria bending over.

[Dartgod]

Originally Posted by Dave Lane

REPOST

http://chiefsplanet.com/BB/showthrea...87#post7492987

Re-Repost

http://chiefsplanet.com/BB/showpost....&postcount=398

[Donger]

Update:

1. Fukushima Daiichi Nuclear Power Plant Status

Tables 1 - 4 track progress made for each of Units 1 - 4 towards fulfilling the three basic safety functions of the IAEA safety standards: prevention of criticality, removal of decay heat and mitigation of radioactive releases. The tables replace the three-colour table that was used previously. The charts are cross-referenced to the Tokyo Electric Power Company (TEPCO) "Roadmap" plan to bring the nuclear reactors and the spent fuel pools at the Fukushima Daiichi plant to a stable cooling condition and to mitigate radioactive releases.

On 17 May 2011, TEPCO provided a status report against the TEPCO "Roadmap". Progress has been made during the last month since the issuing of the Roadmap on 17 April 2011. While the basic policy and targets defined in the Roadmap remain, several changes were made to account for new information obtained and progress made to date.

On 13 May TEPCO commenced the preparatory work for the installation of a cover for the reactor building of Unit 1. The reactor building cover will be installed as an emergency measure to prevent the dispersion of radioactive substances until mid- to long term measures, including radiation shielding, are implemented.

TEPCO has reported that information obtained after calibration of the reactor water level gauges of Unit 1 shows that the actual water level in the Unit 1 reactor pressure vessel was lower than was indicated, showing that the fuel was completely uncovered. The results of provisional analysis show that fuel pellets melted and fell to the bottom of reactor pressure vessel at a relatively early stage in the accident.

TEPCO reported that "most part of the fuel is considered to be submerged in the bottom of reactor pressure vessel and some part exposed." TEPCO also reported that leakage of cooling water from the reactor pressure vessel is likely to have occurred. However, TEPCO considers that the actual damage to the reactor pressure vessel is limited, on the basis of the temperatures now being measured around the reactor pressure vessel.

With regard to the status of the reactor core of Unit 1, TEPCO believes that because the fuel has been being cooled continuously by means of water injection, it is unlikely that the situation could result in a future release of large amounts of radioactive material.

The results of the analysis are provisional; TEPCO will continue to conduct investigations. Similar analyses will be conducted for Units 2 and 3.

Nitrogen gas is still being injected into the containment vessel in Unit 1 to reduce the possibility of hydrogen combustion inside the containment vessel.

In Units 1, 2 and 3 fresh water is being continuously injected into the reactor pressure vessel; temperatures and pressures remain stable.

To protect against potential damage as a result of future earthquakes, TEPCO started work on 9 May to install a supporting structure for the floor of the spent fuel pool of Unit 4.

Fresh water is being injected as necessary into the spent fuel pools of Units 1 - 4.

Stagnant water with high levels of radioactivity in the basement of the turbine buildings of Units 1, 2 and 3 is being transferred to the condensers, the radioactive waste treatment facility, the high-temperature incinerator building and temporary storage tanks. Stagnant water in the basement of the turbine building of Unit 6 is being transferred to a temporary tank. Countermeasures against the outflow of water to the sea and to prevent and minimize the dispersion of radionuclides in water have been put in place.

Full-scale spraying of anti-scattering agent is continuing at the site with the use of both conventional and remote controlled equipment.

[Donger]

Tokyo, Japan (CNN) -- Two of the damaged reactors at the crippled Fukushima Daiichi nuclear power plant in Japan may be riddled with holes, according to the facility's owner.

The holes may be as big as 7 to 10 centimeters ( 2.8- 3.9 inches), Tokyo Electric Power Co. said in a 225-page document submitted to Japan's Nuclear and Industrial Safety Agency.

In the report, Tokyo Electric says the containment vessel of reactor No. 1 may have developed a hole as big as 3 centimeters in diameter 18 hours after the quake.

Fifty hours after the quake, the hole may have widened to 7 centimeters, the report said.

In reactor No. 2, the containment vessel may have developed a hole as wide as 10 centimeters 21 hours after the quake.

The nuclear plant has suffered cooling problems and radiation leaks since a March 11 earthquake and tsunami.

The hydrogen explosion four days after the crisis began may have led to the formation of a second hole in reactor No. 2, as wide as 10 centimeters in diameter.

"This report is not conclusive. No one has entered these areas and we cannot confirm this as fact," TEPCO said, adding that the report is making preliminary assumptions about what happened inside the reactors.

A hole in the reactor's containment vessel means there is a high probability of the leakage of radioactive material into the reactor building.

The amount of radioactive material in all three of the reactor buildings has hampered TEPCO's ability to build an effective cooling system. TEPCO says a cooling system is a critical step to leading to a cold shutdown, still estimated to be five to eight months away.

Nuclear experts and scientists have long suspected this sort of damage to the containers of the reactors at the crippled plant, as well as a full meltdown of the fuel rods in reactors 1, 2 and 3.

[Donger]

3 nuclear reactors melted down after quake, Japan confirms

http://www.cnn.com/2011/WORLD/asiapc...html?hpt=hp_t2

Tokyo (CNN) -- Japan's Fukushima Daiichi nuclear power plant experienced full meltdowns at three reactors in the wake of an earthquake and tsunami in March, the country's Nuclear Emergency Response Headquarters said Monday.

The nuclear group's new evaluation, released Monday, goes further than previous statements in describing the extent of the damage caused by an earthquake and tsunami on March 11.

The announcement will not change plans for how to stabilize the Fukushima Daiichi plant, the agency said.

Reactors 1, 2 and 3 experienced a full meltdown, it said.

The plant's owner, Tokyo Electric Power Co., admitted last month that nuclear fuel rods in reactors 2 and 3 probably melted during the first week of the nuclear crisis.

It had already said fuel rods at the heart of reactor No. 1 melted almost completely in the first 16 hours after the disaster struck. The remnants of that core are now sitting in the bottom of the reactor pressure vessel at the heart of the unit and that vessel is now believed to be leaking.

A "major part" of the fuel rods in reactor No. 2 may have melted and fallen to the bottom of the pressure vessel 101 hours after the earthquake and tsunami that crippled the plant, Tokyo Electric said May 24.

The same thing happened within the first 60 hours at reactor No. 3, the company said, in what it called its worst-case scenario analysis, saying the fuel would be sitting at the bottom of the pressure vessel in each reactor building.

But Tokyo Electric at the same time released a second possible scenario for reactors 2 and 3, one that estimated a full meltdown did not occur. In that scenario, the company estimated the fuel rods may have broken but may not have completely melted.

Temperature data showed the two reactors had cooled substantially in the more than two months since the incident, Tokyo Electric said in May.

The earthquake and tsunami knocked out cooling systems at Fukushima Daiichi, causing the three operating reactors to overheat. That compounded a natural disaster by spewing radioactive material into the atmosphere.

Tokyo Electric avoided using the term "meltdown," and says it was keeping the remnants of the core cool. But U.S. experts interviewed by CNN after the company's announcement in May said that while it may have been containing the situation, the damage had already been done.

"On the basis of what they showed, if there's not fuel left in the core, I don't know what it is other than a complete meltdown," said Gary Was, a University of Michigan nuclear engineering professor and CNN consultant. And given the damage reported at the other units, "It's hard to imagine the scenarios can differ that much for those reactors."

A massive hydrogen explosion -- a symptom of the reactor's overheating -- blew the roof off the No. 1 unit the day after the earthquake, and another hydrogen blast ripped apart the No. 3 reactor building two days later. A suspected hydrogen detonation within the No. 2 reactor is believed to have damaged that unit on March 15.

[loochy]

Uhm so why are we all still alive then?

[Donger]

Originally Posted by loochy

Uhm so why are we all still alive then?

Definitions vary on what a "full meltdown" is. Some folks will only use that term when the PV is ripped apart (e.g., Chernobyl). Others will use it when the core fully melts and plops down inside the PV, without a massive breach. This is the latter.

[loochy]

Originally Posted by Donger

Definitions vary on what a "full meltdown" is. Some folks will only use that term when the PV is ripped apart (e.g., Chernobyl). Others will use it when the core fully melts and plops down inside the PV, without a massive breach. This is the latter.

*Sigh* I know that.

I was trying to be like googlegoogle.

[Donger]

Originally Posted by loochy

*Sigh* I know that.

I was trying to be like googlegoogle.

Oh. Sorry.