Japanese nuclear disaster

[Secret Service]

another Chernobyl ...omg

 

[hembo]

10.27am GMT: Water levels have fallen far enough to partly expose fuel rods at the No 2 reactor at Fukushima Daiichi, according to the Jiji news agency.

 

[hembo]

10.50am GMT: The Guardian's science correspondent, Ian Sample, writes that the first report from Japan's Nuclear and Industrial Safety Agency this morning described a rise in radioactivity around the Fukushima nuclear power station when compared to Sunday's levels.

The highest level, at 680microSieverts per hour, was measured earlier on Monday in a direction north-northwest of the plant, the wind direction at the time. To put that level in perspective, the typical dose we receive from background radiation is 2000 microSieverts a year. So spending an hour at the monitoring post leads to an exposure equivalent to around four months due to background.

The Nuclear and Industrial Safety Agency report that at 1.10am local time on Monday, engineers had to stop pumping water into reactors one and three at Fukushima because seawater pits ran dry. Injection of water in the reactor 3 - the one that uses a plutonium mix fuel - restarted at 3.20am. They give no further details of the situation at reactor 1

 

[hembo]

11.09am GMT: Ian Sample has more on the exposure of those fuel rods at reactor 2:

The rods are usually submerged in several metres of water to stop them overheating. Water level gauges at reactors 1 and 3 also suggest that fuel rods are partially exposed, but engineers said pressure readings from the reactors conflict with this and that the water gauges may be faulty. Workers are trying to circulate seawater around all three reactors to keep them cool. Serious melting of fuel rods inside any of the reactors could block the circulation of water.

11.03am: Kyodo News has reported in the last five minutes that the fuel rods at the No 2 reactor at Fukushima Daiichi are now fully exposed.

 

[Capt.Popeye]

^^^
Not looking good.

 

[monitor]

Just reading on CNN the radiation level has decrease .

 

[jbond197]

...................

 

[Punjabbi Munda]

Hard times for Japan...

 

[Dron.ru]

As a result, the stop 11 nuclear power plants, electricity production in Japan decreased by 9 GW. Russia declared readiness to increase energy supplies: may be additionally supplied 200,000 tons of liquefied natural gas and 6 GW of electricity.

 

[anon45]

Tokyo Electric Power Company, which runs the Fukushima Dai-Ichi plant, says radiation levels at the unit are well below the legal limits following this morning's hydrogen explosion. Radiation at Unit 3 measured 10.65 microsieverts; operators must inform the government if a level of 500 microsieverts is reached.

Health experts have stressed that the risk from radiation appears low. Reuters has spoken to the Gregory Hartl of the World Health Organisation, who told the agency:


"At this moment it appears to be the case that the public health risk is probably quite low. We understand radiation that has escaped from the plant is very small in amount."

That has not stopped people from worrying. Singaporean authorities have announced they will test imported Japanese produce for potential radiation "as a precautionary measure".

---------- Post added at 09:15 AM ---------- Previous post was at 09:14 AM ----------

According to a piece in the New York Times, a US aircraft carrier, Ronald Reagan, passed through a radioactive cloud from the Japan nuclear reactors. It is reported that the crew on deck received a month's worth of radiation in an hour.

There is no indication any of the personnel have experienced ill effects from the exposure, officials said

I thought it was helicopters operating from the carrier which passed through the cloud? They had to be scrubbed down, their crew (17) were exposed to a month worth of radiation, and the ships were moved as a precautionary measure

 

[Brotherhood]

Second blast occurs at Japan's nuclear plant as death toll rises - People's Daily Online March 14, 2011

This Oct. 2008 file photo released by Kyodo News Agency on March 13, 2011 shows the reactors of Japan's Fukushima No. 1 nuclear power station. Japan's Nuclear and Industrial Safety Agency said March 14, 2011 that hydrogen blast occurred at the No. 3 nuclear reactor (2nd from left) of Fukushima No. 1 nuclear power plant at 02:01 GMT (11:01 local time). (Xinhua/Kyodo)

A second hydrogen explosion on Monday rocked the quake-stricken nuclear plant in Japan, as the government is going all-out to prevent a nuclear disaster.

Plumes of white smoke were seen coming from the Fukushima No.1 nuclear power plant following a loud explosion at the plant's No. 3 reactor, the Nuclear and Industrial Safety Agency (JNISA) said.

Tokyo Electric Power Co. said seven people went missing and 11 were injured after the explosion.

The agency said the wall of the reactor building collapsed, confirming eye-witness reports that only the building's skeletal structure remained.

The likelihood of high levels of radiation in the area is low, the agency said, but warned the 600 people who were still in the 20-km evacuation zone to leave immediately.

The agency also said large amounts of hydrogen have amassed in the upper parts of the reactor building, where the pressure remained unusually high, similar to that of the No. 1 reactor building, which also exploded on Saturday.

This still image taken from news program by NHK on March 14, 2011 shows the No. 3 nuclear reactor of the Fukushima No. 1 nuclear power station after a hydrogen explosion. Japan's Nuclear and Industrial Safety Agency said Monday that hydrogen blast occurred at the No. 3 nuclear reactor of Fukushima No. 1 nuclear power plant at 02:01 GMT (11:01 local time). (Xinhua/NHK)

Cooling operations at the reactor were continuing to preserve the containment unit, although coolant levels were low, the agency reported.

JNISA had independently verified, however, that the containment vessel in the reactor was still intact.

Speaking at an emergency press conference Monday, Chief Cabinet Secretary Yukio Edano said the explosion did not damage the reactor and the containment vessel and that there was little possibility of mass radiation being leaked into the air.

Edano expressed concern on Sunday that a hydrogen explosion could occur at the plant's No. 3 reactor -- the latest reactor to face a possible meltdown, following a hydrogen blast on Saturday in the plant's No. 1 unit.

A TV station also reported a new tsunami on Monday but it turned out to be a false alarm.

While struggling to avert a nuclear meltdown, the government is also striving to take care of millions of survivors who are still without drinking water, electricity and proper food following Friday's catastrophic 9-magnitude earthquake and ensuing massive tsunamis.

A total of 1,647 people had been killed by 12:00 a.m. (0300 GMT) Monday, the National Police Agency confirmed.

But the death toll is likely to rise significantly, as latest reports from Kyodo News said about 2,000 bodies were found Monday on two shores in Japan's Miyagi Prefecture.

About 1,000 bodies were found washed ashore on Miyagi's Ojika Peninsula and another 1,000 were spotted in the town of Minamisanriku where the prefectural government has been unable to contact some 10,000 people, or over half the local population, the reports said.

The Miyagi prefectural government has decided to ask for help from other prefectures as work to cremate bodies is falling behind, according to the reports.

Miyagi, with a population of about 2.3 million, was one of the hardest hit areas.

While the country is grappling with the widespread damage, countries around the world have also offered help to Japan in dealing with the aftermath of the devastating earthquake.

At least 50 countries and regions have promised to provide relief support, and offers from over 70 specialized rescue teams from around the globe have been received by Japan.

A 15-member Chinese rescue team, which arrived in Japan around midday on Sunday, was set to start search and rescue operations Monday morning in Ofunato city of Japan's northeastern Iwate Prefecture.

China also pledged 30 million yuan (4.57 million U.S. dollars) worth of emergency humanitarian assistance to Japan to help the disaster relief there, the Chinese Ministry of Commerce said Monday.

South Korea dispatched five rescuers and two search dogs on Saturday, and another team of rescue workers left for Japan on Monday to help with the search and rescue efforts there.

Some organizations in Singapore are also offering help to those affected by the quake in northeastern Japan.

 

[CardSharp]

Just heard about a third explosion at the Fukushima nuclear power station. The reports of husbands looking for wives and parents looking for children is heartbreaking...

 

[no_name]

From since the second explosion my impression is that there is nothing they could do really and that all 4 reactors will eventually suffer the same fate.

 

[Solomon2]

Boiling Water Reactors

In a typical commercial boiling-water reactor, (1) the core inside the reactor vessel creates heat, (2) a steam-water mixture is produced when very pure water (reactor coolant) moves upward through the core, absorbing heat, (3) the steam-water mixture leaves the top of the core and enters the two stages of moisture separation where water droplets are removed before the steam is allowed to enter the steam line, and (4) the steam line directs the steam to the main turbine, causing it to turn the turbine generator, which produces electricity. The unused steam is exhausted in to the condenser where it condensed into water. The resulting water is pumped out of the condenser with a series of pumps, reheated and pumped back to the reactor vessel. The reactor's core contains fuel assemblies that are cooled by water circulated using electrically powered pumps. These pumps and other operating systems in the plant receive their power from the electrical grid. If offsite power is lost emergency cooling water is supplied by other pumps, which can be powered by onsite diesel generators. Other safety systems, such as the containment cooling system, also need electric power. Boiling-water reactor’s contain between 370-800 fuel assemblies. link

 

[CardSharp]

Just heard about a third explosion at the Fukushima nuclear power station.

Third explosion heard at Japanese nuclear plant

As the death toll in Japan continues to mount following Friday’s earthquake and tsunami, Japanese authorities are now dealing with a possible meltdown at a damaged nuclear power plant in the heart of the disaster zone.
The trouble began when the quake and tsunami knocked out the plant's power, which subsequently disabled the cooling systems which prevent a meltdown.

Two explosions hit the Fukushima Dai-ichi nuclear plant in northeastern Japan on Monday and early Tuesday, prompting the evacuation of thousands of people from nearby areas. Monday's happened at the facility's Unit 3 reactor, injuring 11 workers. Early Tuesday, Japan's nuclear safety agency said a second explosion was heard at the plant's Unit 2 reactor.
Nearly 200,000 people have been evacuated over the past few days due to problems at the plant.

Tokyo Electric warned after the explosion Monday that operators had lost the ability to cool Unit 2, adding that the fuel rods at that reactor were exposed.

There are six reactors at the Fukushima plant, about 60 kilometres south of Sendai, in the heart of the quake and tsunami zone.
Hydrogen in steam released to reduce pressure inside the reactors set off the explosions.

Chief Cabinet Secretary Yukio Edano said there has been “no massive radioactive leakage.” Officials insist radiation levels measured outside the damaged plant remain within legal limits.
There have now been three explosions at the plant in the last four days.

The explosions in Unit 2 and 3 were preceded by a similar blast Saturday in Unit 1. Operators have been frantically trying to cool the reactors using seawater in a bid to prevent a complete meltdown.
Japanese officials said fuel rods in all three reactors appeared to be melting.
Some experts would classify that as a partial meltdown. Others only use that term to describe a situation when nuclear fuel melts through a reactor’s innermost chamber but not through the containment shell, according to the Associated Press.

A complete meltdown is defined as a situation where the uranium core melts through the outer containment shell. If that were to happen in Japan, the resulting wave of radiation would likely result in widespread health problems.

Up to 160 people may have been exposed to radiation and up to 1,500 people have been scanned.

Japanese Prime Minister Naoto Kan said the quake, tsunami and subsequent economic and nuclear crises are the harshest challenge his country has faced since the Second World War.

The death toll from Friday’s natural disaster could exceed 10,000.

Experts say a Chernobyl situation is unlikely because the Dai-ichi plant has a containment vessel that would capture radioactive materials in the event of a meltdown. Chernobyl had no outer containment shell.

The United States moved an aircraft carrier away from the Dai-ichi plant Monday as a precaution after 17 personnel involved in a helicopter relief mission were exposed to low-level radiation. After being scrubbed down, they were declared contamination-free.

Four nuclear plants in northeastern Japan reported damage from the earthquake and the tsunami.