Japanese nuclear disaster
- Thread starter Cityboy
- Start date
Solomon2
BANNED
- Joined
- Dec 12, 2008
- Messages
- 19,475
- Reaction score
- -37
- Country
- Location
Schematic of Reactor Design at Fukushima Daiichi 1
UPDATE AS OF 5:30 P.M. EDT, MONDAY, MARCH 14:
Tokyo Electric Power Co. reported at 3:00 p.m. EDT that work had resumed to pump seawater into Fukushima Daiichi 2 to maintain safe cooling water levels after the utility was able to vent steam from the pressure vessel. The fuel had been exposed for 140 minutes Monday night due to a malfunctioning pressure relief valve. Water levels later went up to cover more than half of the rods.
The U.S. Nuclear Regulatory Commission reports that the Japanese government has formally asked for assistance from the United States on nuclear power plant cooling issues triggered by the March 11 tsunami.
The agency has already sent two experts on boiling water reactor issues to Japan as part of a U.S. Agency for International Development disaster relief team. The experts now are in Tokyo providing technical assistance. The U.S. NRC is also monitoring the Japanese reactor events around the clock from its headquarters operations center in Rockville, Md.
Prior to the second exposure of the rods around 11 p.m., March 14 local time in Japan, radiation at the plant site was detected at a level twice the maximum seen so far 313 millirem per hour, according to TEPCO.
Chief Cabinet Secretary Yukio Edano said he believes the problem at the plant ''will not develop into a situation similar to Chernobyl, even in the worst case.
The utility said a hydrogen explosion at the nearby No. 3 reactor that occurred Monday morning may have caused a glitch in the cooling system of the No. 2 reactor.
The hydrogen explosion at reactor 3 on March 14 injured 11 people: seven TEPCO workers at the site and four members of the countrys Self-Defense Forces. The reactor's containment vessel was not damaged and the reactor remains safely contained in its primary containment.
Administration, NRC Response to the Accident
At a White House briefing, press secretary Jay Carney said that information is still coming in on the status of nuclear plants in Japan, but that the Obama administration is committed to keeping nuclear energy as part of the U.S. energy portfolio.
Energy Department Deputy Secretary Daniel Poneman said nuclear energy continues to play an important role in providing a low-carbon future.
Gregory Jaczko, chairman of the Nuclear Regulatory Commission, said at the briefing that analysis of the damage, the type of reactor and the distances involved indicate a very low likelihood that any potential fallout from Japan might reach Hawaii or Western states.
U.S. nuclear power plants are built to endure the strain of natural phenomena like hurricanes, earthquakes and tornadoes, Jaczko said. Right now, we continue to believe that nuclear power plants in this country operate safely and securely, he said.
UPDATE AS OF 4:20 P.M. EDT, MONDAY, MARCH 14:
NEI has posted a new document, "Radiation in Perspective," which describes where radiation comes from and how it is measured.
UPDATE AS OF 1:30 P.M. EDT, MONDAY, MARCH 14:
Unit 2 at the Fukushima Daiichi nuclear power plant lost a significant amount of reactor coolant for a second time on Monday. Some of the uranium fuel rods were uncovered for a period of time. A malfunctioning safety relief valve at the plant caused an increase in reactor pressure and hindered injection of coolant back into the reactor. The cause of the relief valve failure is under investigation.
The Japanese government has distributed 230,000 units of potassium iodine to evacuation centers in the area surrounding the Fukushima Daiichi and Fukushima Daini stations, according to officials. Ingestion of potassium iodine can help prevent the accumulation of radioactive iodine in the thyroid.
At the Fukushima Daini site all units have off-site power, and water levels in all units are stable. Plant operators at Daini Unit 1 were able to restore a residual heat remover system, which is now being used to cool the reactor. Work is in progress to achieve a cold shutdown. Workers at Daini Units 2 and 4 are working to restore residual heat removal systems. Unit 3 is in a safe, cold shutdown.
Radiation dose rate measurements observed at four locations around the Daini plant´s perimeter over a 16-hour period on Sunday were all normal.
UPDATE AS OF 5:30 P.M. EDT, MONDAY, MARCH 14:
Tokyo Electric Power Co. reported at 3:00 p.m. EDT that work had resumed to pump seawater into Fukushima Daiichi 2 to maintain safe cooling water levels after the utility was able to vent steam from the pressure vessel. The fuel had been exposed for 140 minutes Monday night due to a malfunctioning pressure relief valve. Water levels later went up to cover more than half of the rods.
The U.S. Nuclear Regulatory Commission reports that the Japanese government has formally asked for assistance from the United States on nuclear power plant cooling issues triggered by the March 11 tsunami.
The agency has already sent two experts on boiling water reactor issues to Japan as part of a U.S. Agency for International Development disaster relief team. The experts now are in Tokyo providing technical assistance. The U.S. NRC is also monitoring the Japanese reactor events around the clock from its headquarters operations center in Rockville, Md.
Prior to the second exposure of the rods around 11 p.m., March 14 local time in Japan, radiation at the plant site was detected at a level twice the maximum seen so far 313 millirem per hour, according to TEPCO.
Chief Cabinet Secretary Yukio Edano said he believes the problem at the plant ''will not develop into a situation similar to Chernobyl, even in the worst case.
The utility said a hydrogen explosion at the nearby No. 3 reactor that occurred Monday morning may have caused a glitch in the cooling system of the No. 2 reactor.
The hydrogen explosion at reactor 3 on March 14 injured 11 people: seven TEPCO workers at the site and four members of the countrys Self-Defense Forces. The reactor's containment vessel was not damaged and the reactor remains safely contained in its primary containment.
Administration, NRC Response to the Accident
At a White House briefing, press secretary Jay Carney said that information is still coming in on the status of nuclear plants in Japan, but that the Obama administration is committed to keeping nuclear energy as part of the U.S. energy portfolio.
Energy Department Deputy Secretary Daniel Poneman said nuclear energy continues to play an important role in providing a low-carbon future.
Gregory Jaczko, chairman of the Nuclear Regulatory Commission, said at the briefing that analysis of the damage, the type of reactor and the distances involved indicate a very low likelihood that any potential fallout from Japan might reach Hawaii or Western states.
U.S. nuclear power plants are built to endure the strain of natural phenomena like hurricanes, earthquakes and tornadoes, Jaczko said. Right now, we continue to believe that nuclear power plants in this country operate safely and securely, he said.
UPDATE AS OF 4:20 P.M. EDT, MONDAY, MARCH 14:
NEI has posted a new document, "Radiation in Perspective," which describes where radiation comes from and how it is measured.
UPDATE AS OF 1:30 P.M. EDT, MONDAY, MARCH 14:
Unit 2 at the Fukushima Daiichi nuclear power plant lost a significant amount of reactor coolant for a second time on Monday. Some of the uranium fuel rods were uncovered for a period of time. A malfunctioning safety relief valve at the plant caused an increase in reactor pressure and hindered injection of coolant back into the reactor. The cause of the relief valve failure is under investigation.
The Japanese government has distributed 230,000 units of potassium iodine to evacuation centers in the area surrounding the Fukushima Daiichi and Fukushima Daini stations, according to officials. Ingestion of potassium iodine can help prevent the accumulation of radioactive iodine in the thyroid.
At the Fukushima Daini site all units have off-site power, and water levels in all units are stable. Plant operators at Daini Unit 1 were able to restore a residual heat remover system, which is now being used to cool the reactor. Work is in progress to achieve a cold shutdown. Workers at Daini Units 2 and 4 are working to restore residual heat removal systems. Unit 3 is in a safe, cold shutdown.
Radiation dose rate measurements observed at four locations around the Daini plant´s perimeter over a 16-hour period on Sunday were all normal.
Solomon2
BANNED
- Joined
- Dec 12, 2008
- Messages
- 19,475
- Reaction score
- -37
- Country
- Location
UPDATE AS OF 9:40 P.M. EDT, MONDAY, MARCH 14:
An explosion in the vicinity of the suppression pool at Fukushima Daiichi 2 just after 6:20 a.m. Japan Standard Time (5:20 p.m. EDT) may have damaged a portion of the reactor’s primary containment structure.
Pressure in the suppression pool has been reported to have decreased to ambient atmospheric pressure shortly after the blast. Plant operator Tokyo Electric Power Co. (TEPCO) has reported possible damage to the reactor’s pressure-suppression system. Radiation levels at local monitoring stations have risen but are still in flux. TEPCO has evacuated some workers from all three Fukushima reactors with the exception of approximately 50 workers involved in sea water pumping activities into the reactors as part of emergency cooling efforts.
Residents within a 20-kilometer (12.5 mile) zone around the plant were ordered to evacuate on Saturday following a hydrogen explosion at Unit 1. Another hydrogen explosion occurred this morning (U.S. time) at Unit 3.
Efforts to inject sea water into Unit 2 have been complicated by a faulty pressure relief valve. The fuel at Unit 2 has been exposed at least twice, before being re-covered with sea water.
Japan's Chief Cabinet Secretary, Yukio Edano, has said a partial defect has been found inside the containment vessel of reactor 2 at the Fukushima Daiichi nuclear power plant.
An explosion in the vicinity of the suppression pool at Fukushima Daiichi 2 just after 6:20 a.m. Japan Standard Time (5:20 p.m. EDT) may have damaged a portion of the reactor’s primary containment structure.
Pressure in the suppression pool has been reported to have decreased to ambient atmospheric pressure shortly after the blast. Plant operator Tokyo Electric Power Co. (TEPCO) has reported possible damage to the reactor’s pressure-suppression system. Radiation levels at local monitoring stations have risen but are still in flux. TEPCO has evacuated some workers from all three Fukushima reactors with the exception of approximately 50 workers involved in sea water pumping activities into the reactors as part of emergency cooling efforts.
Residents within a 20-kilometer (12.5 mile) zone around the plant were ordered to evacuate on Saturday following a hydrogen explosion at Unit 1. Another hydrogen explosion occurred this morning (U.S. time) at Unit 3.
Efforts to inject sea water into Unit 2 have been complicated by a faulty pressure relief valve. The fuel at Unit 2 has been exposed at least twice, before being re-covered with sea water.
Japan's Chief Cabinet Secretary, Yukio Edano, has said a partial defect has been found inside the containment vessel of reactor 2 at the Fukushima Daiichi nuclear power plant.
Dance
SENIOR MEMBER
- Joined
- Jul 20, 2010
- Messages
- 4,850
- Reaction score
- 0
Japan warns radioactive levels high around plant after blast
TOKYO: Japan’s prime minister said on Tuesday that radioactive levels had become high around an earthquake-stricken nuclear power plant after an explosion there, and there was a risk of radiation leaking into the atmosphere.
Naoto Kan urged people within 30 km of the facility north of Tokyo to remain indoors and the French embassy in the capital warned in an advisory that a low level of radioactive wind could reach Tokyo within 10 hours.
Tuesday’s explosion was the third at the plant since it was damaged in last Friday’s massive earthquake and tsunami.
Authorities have been trying to prevent meltdowns in all three of the Fukishima Daiichi complex’s nuclear reactors by flooding the chambers with sea water to cool them down.
As concern about the crippling economic impact of the double disaster mounted, Japanese stocks plunged 7.0 per cent to their lowest level in nearly two years, compounding a drop of 7.6 per cent the day before.
The full extent of the destruction wreaked by last Friday’s massive quake and tsunami that followed it was still becoming clear, as rescuers combed through the region north of Tokyo where officials say at least 10,000 people were killed.
“It’s a scene from hell, absolutely nightmarish,” said Patrick Fuller of the International Red Cross Federation from the northeastern coastal town of Otsuchi.
Kan has said Japan is facing its worst crisis since World War Two and, with the financial costs estimated at up to $180 billion, analysts said it could tip the world’s third-biggest economy back into recession.
The US Geological Survey upgraded the quake to magnitude 9.0, from 8.9, making it the world’s fourth most powerful since 1900.
Car makers, shipbuilders and technology companies worldwide scrambled for supplies after the disaster shut factories in Japan and disrupted the global manufacturing chain.
“Not Chernobyl”
The fear at the Fukushima complex, 240 km north of Tokyo, is of a major radiation leak after the quake and tsunami knocked out cooling systems. The complex had already seen explosions at its No. 1 and No.3 reactors.
Jiji news agency said Tuesday’s explosion had damaged the roof and steam was rising from the complex. It also reported some workers had been told to leave the plant, a development one expert had warned beforehand could signal a worsening stage for the crisis.
The worst nuclear accident since the Chernobyl disaster in Ukraine in 1986 has drawn criticism that authorities were ill-prepared and revived debate in many countries about the safety of atomic power.
Switzerland put on hold some approvals for nuclear power plants and Germany said it was scrapping a plan to extend the life of its nuclear power stations. The White House said US President Barack Obama remained committed to nuclear energy.
Whilst the Fukuskima plant’s No.1 and No.3 reactors both suffered partial fuel rod meltdowns, operator Tokyo Electric Power Co (TEPCO) had earlier said the No. 2 reactor was now the biggest concern.
A sudden drop in cooling water levels when a pump ran out of fuel had fully exposed the fuel rods for a time, an official said. This could lead to the rods melting down and a possible radioactive leak.
TEPCO had resumed pumping sea water into the reactor early on Tuesday.
“This is nothing like a Chernobyl,” Murray Jennex, a nuclear expert at San Diego State University, said earlier. “At Chernobyl you had no containment structure — when it blew, it blew everything straight out into the atmosphere.”
An explosion at the Soviet Chernobyl plant sent radioactive fallout across northern Europe.
US warships and planes helping with relief efforts moved away from the coast temporarily because of low-level radiation.
The US Seventh Fleet described the move as precautionary.
South Korea, Hong Kong, Singapore and the Philippines said they would test Japanese food imports for radiation.
France’s ASN nuclear safety authority said the accident could be classified as a level 5 or 6 on the international scale of 1 to 7, putting it on a par with the 1979 US Three Mile Island meltdown, higher than the Japanese authorities’ rating.
Japan’s nuclear safety agency has rated the incidents in the No.1 and No.3 reactors as a 4, but has not yet rated the No. 2 reactor.
Towns Flattened
About 850,000 households in the north were still without electricity in near-freezing weather, Tohuku Electric Power Co. said, and the government said at least 1.5 million households lack running water. Tens of thousands of people were missing.
“The situation here is just beyond belief, almost everything has been flattened,” said the Red Cross’s Fuller in Otsuchi, a town all-but obliterated. “The government is saying that 9,500 people, more than half of the population, could have died and I do fear the worst.”
Kyodo news agency reported that 2,000 bodies had been found on Monday in two coastal towns alone.
Japan warns radioactive levels high around plant after blast | World | DAWN.COM
Brotherhood
SENIOR MEMBER
- Joined
- May 31, 2010
- Messages
- 2,439
- Reaction score
- 0
Japan nuclear plant faces prospect of meltdown - People's Daily Online March 15, 2011
Japan's authorities ordered Tuesday morning immediate evacuation of all engineers and workers from the seriously troubled Fukushima nuclear complex, an ominous hint that the three nuclear reactors there face the prospect of meltdown.
Japanese Prime Minister Naoto Kan made a nationally televised statement at 11 am local time to discuss the crisis.
Earlier, a new explosion at the Nuclear Power Station's No 2 reactor before 6 am Tuesday damaged the crucial containment structure made of special steel, and some fuel rods stored there were exposed to the air, meaning large emissions of radioactive materials could incur at any time.
If all workers are now ordered to abandon the complex and no coolants are available to cool the reactor cores, the nuclear fuel rods in all three reactors are likely to melt down, dispersing larger flumes of highly radioactive materials.
It remains to be seen whether nuclear scientists and engineers could find an effective measure to prevent another nuclear disaster, comparative to the Chernobyl Accident 25 years ago, from happening now.
People's Daily Online
Japan's authorities ordered Tuesday morning immediate evacuation of all engineers and workers from the seriously troubled Fukushima nuclear complex, an ominous hint that the three nuclear reactors there face the prospect of meltdown.
Japanese Prime Minister Naoto Kan made a nationally televised statement at 11 am local time to discuss the crisis.
Earlier, a new explosion at the Nuclear Power Station's No 2 reactor before 6 am Tuesday damaged the crucial containment structure made of special steel, and some fuel rods stored there were exposed to the air, meaning large emissions of radioactive materials could incur at any time.
If all workers are now ordered to abandon the complex and no coolants are available to cool the reactor cores, the nuclear fuel rods in all three reactors are likely to melt down, dispersing larger flumes of highly radioactive materials.
It remains to be seen whether nuclear scientists and engineers could find an effective measure to prevent another nuclear disaster, comparative to the Chernobyl Accident 25 years ago, from happening now.
People's Daily Online
Skyline
SENIOR MEMBER
- Joined
- Jan 8, 2011
- Messages
- 3,640
- Reaction score
- 0
- Country
- Location
DO NOT PANIC OVER JAPAN NUKE CRISIS - AEA
The Sri Lankan Atomic Energy Authority today urged the Sri Lankan public not to panic over the unfolding nuclear crisis in Japan, the Authority Chairman Prof. Wimaladarma Abeywickrema told Ada Derana a short while ago.
We are in touch with the International Atomic Energy Agency in Vienna, Austria and we will keep the public informed, he added.
Meanwhile Japan said that the risk of a nuclear leakage was rising at its quake-stricken power plant on the northeast coast and warned any people within a 30 km radius from the Nuclear plant to stay indoors.
Prime Minister Naoto Kan told a news conference that radioactive levels around the Fukushima Daiiichi complex were now high and said authorities were doing their utmost to prevent leaks from the reactor from spreading.
source:
---------
I just wondering how far the radioactive levels can spread?
The Sri Lankan Atomic Energy Authority today urged the Sri Lankan public not to panic over the unfolding nuclear crisis in Japan, the Authority Chairman Prof. Wimaladarma Abeywickrema told Ada Derana a short while ago.
We are in touch with the International Atomic Energy Agency in Vienna, Austria and we will keep the public informed, he added.
Meanwhile Japan said that the risk of a nuclear leakage was rising at its quake-stricken power plant on the northeast coast and warned any people within a 30 km radius from the Nuclear plant to stay indoors.
Prime Minister Naoto Kan told a news conference that radioactive levels around the Fukushima Daiiichi complex were now high and said authorities were doing their utmost to prevent leaks from the reactor from spreading.
source:
---------
I just wondering how far the radioactive levels can spread?
CardSharp
ELITE MEMBER
- Joined
- Apr 17, 2010
- Messages
- 9,355
- Reaction score
- 0
Oh no......
tanlixiang28776
SENIOR MEMBER
- Joined
- Jan 26, 2011
- Messages
- 3,948
- Reaction score
- 0
It gets worse. There is another reactor.
CardSharp
ELITE MEMBER
- Joined
- Apr 17, 2010
- Messages
- 9,355
- Reaction score
- 0
If they are evacuating the engineers, it means that there is nothing more they can do to cool the cores.
hembo
SENIOR MEMBER
- Joined
- Feb 6, 2009
- Messages
- 3,395
- Reaction score
- -3
- Country
- Location
The International Atomic Energy Agency says the Fukushima crisis is unlikely to become another Chernobyl. Authorities have set up a 20km (12 mile) exclusion zone around the Fukushima Daiichi plant. Meanwhile, the US agreed to Japan's formal request for supplies and equipment to tackle the crisis.
I read in a diffrent expert opinion that in case of plutonium based fuel, the isotrops can travel to any unsuspecting location and fall in form of rain. Reactor 1 is Uraneum based and reactor 3 is a mixed (Uranium+ Plutonium) fuel.
Does anyone know what is the fuel in reactor 2, which is the main culprit as of now?
hembo
SENIOR MEMBER
- Joined
- Feb 6, 2009
- Messages
- 3,395
- Reaction score
- -3
- Country
- Location
• Low-level radioactive wind from the damaged reactors could reach Tokyo later this evening, based on current winds, while scenes of panic in the capital have been reported after minute amount of radiation were detected in Tokyo.
A businessman is reflected on a share prices board as he watches the sharply dropped figure of the Tokyo Stock Exchange in Tokyo on March 15, 2011. Photograph: -/AFP/Getty Images
hembo
SENIOR MEMBER
- Joined
- Feb 6, 2009
- Messages
- 3,395
- Reaction score
- -3
- Country
- Location
5.10am GMT: Here's a rundown of the state of the reactors at the Fukushima Daiichi (number one) plant:
Reactor 1: Earlier Hydrogen explosion has blown off the top of the reactor building
Reactor 2: Containment vessel possibly damaged in explosion, coolant pumps damaged by earlier explosions and valves closed, fuel rods exposed and may be leaking radioactive water from suppression pool
Reactor 3: Earlier Hydrogen explosion, cloud of steam still rising, top half of reactor's building blown off
Reactor 4: Fire broke out late Monday, probably caused by nearby explosions, now put out, spent nuclear fuel may have been exposed, destroying the reactor's housing. The fire may be the cause of the high levels of radiation at the site
Reactor 1: Earlier Hydrogen explosion has blown off the top of the reactor building
Reactor 2: Containment vessel possibly damaged in explosion, coolant pumps damaged by earlier explosions and valves closed, fuel rods exposed and may be leaking radioactive water from suppression pool
Reactor 3: Earlier Hydrogen explosion, cloud of steam still rising, top half of reactor's building blown off
Reactor 4: Fire broke out late Monday, probably caused by nearby explosions, now put out, spent nuclear fuel may have been exposed, destroying the reactor's housing. The fire may be the cause of the high levels of radiation at the site
Similar threads
