Earthquake Damages Japanese Nuclear Plant At Fukushima Daiichi, Four Explosions and Four Nuclear Reactors Flooded With Seawater To Contain Release Of Radioactive Material and Plant Released Radioactive Materials To Stop Pressure Buildup–Partial Meltdown Of Nuclear Core Feared–Radioactive Material Escaping From Plant–Over 250,000 Ordered Evacuated From 20 Kilometer (12.4 Miles) Radius From Plant–Leaked Radioactive Water From Reactor 3 More Than 100,000 Normal Levels–Highest Severity Level 7 Nuclear Crisis–Videos
Japanese Nuclear Crisis Rated a 7, Considered Equal to Chernobyl
By Mary Shomon
“…Japanese officials have announced that they have upgraded the severity of the Fukushima nuclear accident from a 5 to the maximum of 7, the highest rating given to a nuclear accident. The IAEA describes a level 7 event as “a major release of radioactive material with widespread health and environmental effects requiring implementation of planned and extended countermeasures”. The only nuclear accident ever rated 7 by the International Atomic Energy Agency’s (IAEA) has been Chernobyl, which took place almost 25 years ago, on April 26, 1986.
Japanese officials are cautioning that the new ranking does not mean that the public health threat from Fukushima is the same as Chernobyl, and have claimed that the radiation that was released as a result of the Chernobyl disaster is ten times the amount released by the crippled Japanese reactor at Fukushima.
To date, about 70,000 people living in a 12-mile radius of the plant have been evacuated, and another 130,000 who live within 12 to 20 miles of the plant have been told to either leave, or stay indoors, and no radiation-related deaths have been reported. …”
http://thyroid.about.com/b/2011/04/12/japanese-nuclear-seven-chernobyl.htm
Japan nuclear crisis level raised to it’s highest level which is 7 CCTV News
Japan Raises Nuclear Threat To Level 7, Equal To Chernobyl
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AP: Japan Nuke Plants Get Power, Massive Cleanup On
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BREAKING! Japanese Citizens Now Being Instructed To Move Away From SECOND Nuclear Power Plant!
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Fukushima nuclear reactor radiation exposure: How far will this go?
Japan: Prime Minister – Radiation Leaks – 3rd Reactor Explosion – Meltdown Fears – 3am GMT
Third Explosion at Japanese Nuclear Reactor Plant
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Second explosion at Japanese nuclear plant
Japanese nuclear Power plant meldown, Uranium Cores Exposed!
Huge Explosion Blasts Smokes at Japan Second Nuclear Power Plant Reactor
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JAPAN: Problems still plague Fukushima nuclear plants – NHK 110313
Japan’s radiation exposure risks
What Is a Nuclear Meltdown?
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Japanese Nuclear Plants’ Cooling Systems Fail PLANT EXPLODED
Expert Analyzes Japanese Nuclear Plant Explosion Video
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Explosion at nuclear plant in Japan
Japanese Nuclear Plants’ Cooling Systems Fail PLANT EXPLODED
Japan 2011 Earthquake 6 – Nuclear Alert 2 of 2 – BBC News America
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Japan Earthquake Damage to Nuclear Plants Blast 3-9-2011
Japan declares Nuclear Emergency after earthquake
Background Articles and Information
Nuclear Power – How it Works
How nuclear energy works
CGS nuclear power plant tour (how it works)
Chief Nuclear Engineer: The TRUE Situation at Fukushima – Worse Than Chernobyl!
Arnold “Arnie” Gundersen
Arnold “Arnie” Gundersen is chief engineer of energy consulting company Fairewinds Associates and a former nuclear power industry executive, and who has questioned the safety of the Westinghouse AP1000, a proposed third-generation nuclear reactor.[1] Gundersen has also expressed concerns about the operation of the Vermont Yankee Nuclear Power Plant. He served as an expert witness in the investigation of the Three Mile Island accident.[2]
http://en.wikipedia.org/wiki/Arnold_Gundersen
Fukushima I Nuclear Power Plant
“…The Fukushima I Nuclear Power Plant(福島第一原子力発電所 Fukushima Dai-Ichi Genshiryoku Hatsudensho, Fukushima I NPP, 1F), often referred to as Fukushima Dai-ichi, is a nuclear power plant located in the town of Okuma in the Futaba District of Fukushima Prefecture, Japan. The plant consists of six boiling water reactors. These light water reactors have a combined power of 4.7 GW, making Fukushima I one of the 25 largest nuclear power stations in the world. Fukushima I was the first nuclear plant to be constructed and run entirely by the Tokyo Electric Power Company (TEPCO).In March 2011, in the immediate wake of the Sendai earthquake and tsunami, the Japanese government declared an “atomic power emergency” and evacuated thousands of residents living close to Fukushima I. Ryohei Shiomi of Japan’s nuclear safety commission said that officials were concerned about the possibility of a meltdown.[1][2]Fukushima II Nuclear Power Plant, 11.5 kilometres (7.1 mi) to the south, is also run by TEPCO.The reactors for units 1, 2, and 6 were supplied by General Electric, for units 3 and 5 by Toshiba, and unit 4 by Hitachi. Architectural design for General Electric’s units was done by Ebasco. All construction was done by Kajima.[3] From September 2010, unit 3 has been fueled by mixed-oxide (MOX) fuel.[4][5] Units 1–5 had/have a Mark 1 type (light bulb torus) containment structure, unit 6 has Mark 2 type (over/under) containment structure.[6]Unit 1 is a 439 MW boiling water reactor (BWR3) constructed in July 1967. It commenced commercial electrical production March 26, 1971, and was scheduled for shutdown on March, 2011. It was damaged during the 2011 Sendai earthquake and tsunami.[7] Unit 1 was designed for a peak ground acceleration of 0.18 g (1.74 m/s2) and a response spectrum based on the 1952 Kern County earthquake.[6] It was inspected after the 1978 Miyagi earthquake, but no damage to the critical parts of the reactor was discovered.[6] …”
http://en.wikipedia.org/wiki/Fukushima_I_Nuclear_Power_Plant
Japan evacuates 50,000 after nuclear power plant explosion
By Barbara Demick, Los Angeles Times
“…Japanese officials, trying to calm a stunned nation, say the explosion didn’t damage the Fukushima Daiichi nuclear reactor itself but merely caused the collapse of a wall outside. Japanese television is reporting that at least three residents among 90 tested showed excess exposure to radiation.More than 50,000 people were evacuated Saturday after an explosion at a Japanese nuclear plant hurled plumes of smoke over the Pacific Ocean and sent officials scrambling to calm residents already shattered by the largest earthquake in the nation’s recorded history.Japanese authorities hastened to assure the public there was no danger of a meltdown at the the Fukushima Daiichi plant along the lines of the 1986 disaster at the Chernobyl nuclear plant in Ukraine, but they were unable to explain why excess levels of radiation were detected outside the plant’s grounds.Japanese Cabinet Secretary Yukio Edano said the explosion at the Fukushima Daiichi plant was caused by a buildup of hydrogen in the cooling system. He insisted that the explosion didn’t cause any damage to the reactor itself but merely caused the collapse of a wall outside.”We are evacuating people just as a precaution,” Edano said at a news conference, even as television footage showed white smoke billowing from the reactor, followed by a black cloud. “There is no risk to inhabitants of the area.”
…”
http://www.latimes.com/news/nationworld/world/la-fg-japan-quake-main-20110313,0,738219.story
Japan evacuates 50,000 after nuclear power plant explosion
By Barbara Demick, Los Angeles Times
“…Japanese officials, trying to calm a stunned nation, say the explosion didn’t damage the Fukushima Daiichi nuclear reactor itself but merely caused the collapse of a wall outside. Japanese television is reporting that at least three residents among 90 tested showed excess exposure to radiation.More than 50,000 people were evacuated Saturday after an explosion at a Japanese nuclear plant hurled plumes of smoke over the Pacific Ocean and sent officials scrambling to calm residents already shattered by the largest earthquake in the nation’s recorded history.Japanese authorities hastened to assure the public there was no danger of a meltdown at the the Fukushima Daiichi plant along the lines of the 1986 disaster at the Chernobyl nuclear plant in Ukraine, but they were unable to explain why excess levels of radiation were detected outside the plant’s grounds.Japanese Cabinet Secretary Yukio Edano said the explosion at the Fukushima Daiichi plant was caused by a buildup of hydrogen in the cooling system. He insisted that the explosion didn’t cause any damage to the reactor itself but merely caused the collapse of a wall outside.”We are evacuating people just as a precaution,” Edano said at a news conference, even as television footage showed white smoke billowing from the reactor, followed by a black cloud. “There is no risk to inhabitants of the area.”
…”
http://www.latimes.com/news/nationworld/world/la-fg-japan-quake-main-20110313,0,738219.story
Another Look at the Nuclear Situation in Japan, Part II”…The emergency cooling system ultimately failed at the Number 1 reactor at Fukushima. In order to prevent the possibility of a meltdown, they’ve decided to flood the containment vessel with salt water and boric acid. The water, as always, is intended to cool the reactor. The salt will corrode all the metal in the reactor over time, so this move means they’ve decided that the number 1 reactor is a loss, which probably has as much to do with the reactor’s age as anything else. The boric acid, on the other hand, is intended to slow the chain reaction further. As the result of a chemical reaction, hydrogen gas began to build up. Hydrogen gas being very flammable, this buildup caused the explosion.It is important to note that according to experts (I’m going with David Lochbaum who was cited in the New York Times) this happened in the turbine hall, NOT in the containment vessel where the nuclear fuel is. A number of alarmists have suggested that the fact that it happened outside of the containment vessel means there is a leak, but this doesn’t seem to be the case to me. There are two general designs of boiling water reactors: in one the steam that is produced by water being exposed to the core is used to turn the turbines that produce electricity directly, and in the other there is an intermediary heat exchange so that the irradiated water isn’t used to turn the turbines. Presumably (and I don’t know this to be true, but it seems likely), this reactor is of the former design. If this is the case, the turbine hall is constantly exposed to irradiated gases and so can be used to store gases in case of an emergency. Of course, this is all a bit of guess work because I don’t have any special knowledge and am relying on news reports and my less than technical understanding of reactor design.The explosion was quite alarming, but it did not damage the containment vessel as far as anyone can tell. All of the really nasty stuff remains safely tucked away in many tons of steel and concrete. According to reports, the explosion did not increase the amount of radiation present outside of the plant. I’m not entirely clear on how this could be given that the turbine hall likely housed a fair bit of radiation. …”
http://bellum.stanfordreview.org/?p=3126
http://www.japannuclear.com/nuclearpower/program/location.html
Fukushima nuclear plant blast puts Japan on high alert
“..Japan is battling to stave off a nuclear disaster after an explosion at a north-eastern nuclear plant in the wake of the enormous earthquake and tsunami.
Authorities are evacuating tens of thousands of residents living within a 12 mile (20km) radius of the Fukushima Daiichi plant and those within 6 miles of a second installation in Futuba, 150 miles north of Tokyo.The explosion followed warnings of a possible meltdown after problems with the cooling system and confirmation of a radiation leak at Fukushima No 1 plant. But nuclear safety officials said it was unlikely the reactor had suffered serious damage, according to the Kyodo news agency.
It is feared that 1,300 people died in Friday’s double disaster, most being killed as the wall of mud and water engulfed buildings, roads and vehicles, Japanese media reported. But the priority now is to tackle the crisis at the power plant. …”
http://www.guardian.co.uk/world/2011/mar/12/fukushima-nuclear-blast-japan-alert
Nuclear Power Plants and Earthquakes
“…
-
Japanese, and most other, nuclear plants are designed to withstand earthquakes, and in the event of major earth movement, to shut down safely.
-
In 1995, the closest nuclear power plants, some 110 km north of Kobe, were unaffected by the severe Kobe-Osaka earthquake, but in 2004, 2005, 2007 and 2009 Japanese reactors shut down automatically due to ground acceleration exceeding their trip settings.
-
In 1999, three nuclear reactors shut down automatically during the devastating Taiwan earthquake, and were restarted two days later.
Design criteriaNuclear facilities are designed so that earthquakes and other external events will not jeopardise the safety of the plant. In France for instance, nuclear plants are designed to withstand an earthquake twice as strong as the 1000-year event calculated for each site. It is estimated that, worldwide, 20% of nuclear reactors are operating in areas of significant seismic activity.Because of the frequency and magnitude of earthquakes in Japan, particular attention is paid to seismic issues in the siting, design and construction of nuclear power plants. The seismic design of such plants is based on criteria far more stringent than those applying to non-nuclear facilities. Power reactors are also built on hard rock foundations (not sediments) to minimise seismic shaking.Japanese nuclear power plants are designed to withstand specified earthquake intensities evident in ground motion. These used to be specified as S1 and S2, but now simply Ss, in Gal units. The plants are fitted with seismic detectors. If these register ground motions of a set level (formerly 90% of S1), systems will be activated to automatically bring the plant to an immediate safe shutdown. The logarithmic Richter magnitude scale (or more precisely the Moment Magnitude Scale more generally used today) measures the overall energy released in an earthquake, and there is not always a good correlation between that and intensity (ground motion) in a particular place. Japan has a seismic intensity scale in shindo units 0 to 7, with weak/strong divisions at levels 5 & 6, hence ten levels. This describes the surface intensity at particular places, rather than the magnitude of the earthquake itself.
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Japan’s radiation exposure risks
What Is a Nuclear Meltdown?
3rd NUCLEAR PLANT IN JAPAN HAS FAILED Nuclear crisis worsens
Japanese Nuclear Plants’ Cooling Systems Fail PLANT EXPLODED
Expert Analyzes Japanese Nuclear Plant Explosion Video
Meltdown threat: Japan ‘preparing for worst’
Explosion at nuclear plant in Japan
Japanese Nuclear Plants’ Cooling Systems Fail PLANT EXPLODED
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Background Articles and Information
Nuclear Power – How it Works
How nuclear energy works
CGS nuclear power plant tour (how it works)
Chief Nuclear Engineer: The TRUE Situation at Fukushima – Worse Than Chernobyl!
Arnold “Arnie” Gundersen
Arnold “Arnie” Gundersen is chief engineer of energy consulting company Fairewinds Associates and a former nuclear power industry executive, and who has questioned the safety of the Westinghouse AP1000, a proposed third-generation nuclear reactor.[1] Gundersen has also expressed concerns about the operation of the Vermont Yankee Nuclear Power Plant. He served as an expert witness in the investigation of the Three Mile Island accident.[2]
http://en.wikipedia.org/wiki/Arnold_Gundersen
Fukushima I Nuclear Power Plant
“…The Fukushima I Nuclear Power Plant(福島第一原子力発電所 Fukushima Dai-Ichi Genshiryoku Hatsudensho, Fukushima I NPP, 1F), often referred to as Fukushima Dai-ichi, is a nuclear power plant located in the town of Okuma in the Futaba District of Fukushima Prefecture, Japan. The plant consists of six boiling water reactors. These light water reactors have a combined power of 4.7 GW, making Fukushima I one of the 25 largest nuclear power stations in the world. Fukushima I was the first nuclear plant to be constructed and run entirely by the Tokyo Electric Power Company (TEPCO).In March 2011, in the immediate wake of the Sendai earthquake and tsunami, the Japanese government declared an “atomic power emergency” and evacuated thousands of residents living close to Fukushima I. Ryohei Shiomi of Japan’s nuclear safety commission said that officials were concerned about the possibility of a meltdown.[1][2]Fukushima II Nuclear Power Plant, 11.5 kilometres (7.1 mi) to the south, is also run by TEPCO.The reactors for units 1, 2, and 6 were supplied by General Electric, for units 3 and 5 by Toshiba, and unit 4 by Hitachi. Architectural design for General Electric’s units was done by Ebasco. All construction was done by Kajima.[3] From September 2010, unit 3 has been fueled by mixed-oxide (MOX) fuel.[4][5] Units 1–5 had/have a Mark 1 type (light bulb torus) containment structure, unit 6 has Mark 2 type (over/under) containment structure.[6]Unit 1 is a 439 MW boiling water reactor (BWR3) constructed in July 1967. It commenced commercial electrical production March 26, 1971, and was scheduled for shutdown on March, 2011. It was damaged during the 2011 Sendai earthquake and tsunami.[7] Unit 1 was designed for a peak ground acceleration of 0.18 g (1.74 m/s2) and a response spectrum based on the 1952 Kern County earthquake.[6] It was inspected after the 1978 Miyagi earthquake, but no damage to the critical parts of the reactor was discovered.[6] …”
http://en.wikipedia.org/wiki/Fukushima_I_Nuclear_Power_Plant
Japan evacuates 50,000 after nuclear power plant explosion
By Barbara Demick, Los Angeles Times
“…Japanese officials, trying to calm a stunned nation, say the explosion didn’t damage the Fukushima Daiichi nuclear reactor itself but merely caused the collapse of a wall outside. Japanese television is reporting that at least three residents among 90 tested showed excess exposure to radiation.More than 50,000 people were evacuated Saturday after an explosion at a Japanese nuclear plant hurled plumes of smoke over the Pacific Ocean and sent officials scrambling to calm residents already shattered by the largest earthquake in the nation’s recorded history.Japanese authorities hastened to assure the public there was no danger of a meltdown at the the Fukushima Daiichi plant along the lines of the 1986 disaster at the Chernobyl nuclear plant in Ukraine, but they were unable to explain why excess levels of radiation were detected outside the plant’s grounds.Japanese Cabinet Secretary Yukio Edano said the explosion at the Fukushima Daiichi plant was caused by a buildup of hydrogen in the cooling system. He insisted that the explosion didn’t cause any damage to the reactor itself but merely caused the collapse of a wall outside.”We are evacuating people just as a precaution,” Edano said at a news conference, even as television footage showed white smoke billowing from the reactor, followed by a black cloud. “There is no risk to inhabitants of the area.”
…”
http://www.latimes.com/news/nationworld/world/la-fg-japan-quake-main-20110313,0,738219.story
Japan evacuates 50,000 after nuclear power plant explosion
By Barbara Demick, Los Angeles Times
“…Japanese officials, trying to calm a stunned nation, say the explosion didn’t damage the Fukushima Daiichi nuclear reactor itself but merely caused the collapse of a wall outside. Japanese television is reporting that at least three residents among 90 tested showed excess exposure to radiation.More than 50,000 people were evacuated Saturday after an explosion at a Japanese nuclear plant hurled plumes of smoke over the Pacific Ocean and sent officials scrambling to calm residents already shattered by the largest earthquake in the nation’s recorded history.Japanese authorities hastened to assure the public there was no danger of a meltdown at the the Fukushima Daiichi plant along the lines of the 1986 disaster at the Chernobyl nuclear plant in Ukraine, but they were unable to explain why excess levels of radiation were detected outside the plant’s grounds.Japanese Cabinet Secretary Yukio Edano said the explosion at the Fukushima Daiichi plant was caused by a buildup of hydrogen in the cooling system. He insisted that the explosion didn’t cause any damage to the reactor itself but merely caused the collapse of a wall outside.”We are evacuating people just as a precaution,” Edano said at a news conference, even as television footage showed white smoke billowing from the reactor, followed by a black cloud. “There is no risk to inhabitants of the area.”
…”
http://www.latimes.com/news/nationworld/world/la-fg-japan-quake-main-20110313,0,738219.story
Another Look at the Nuclear Situation in Japan, Part II”…The emergency cooling system ultimately failed at the Number 1 reactor at Fukushima. In order to prevent the possibility of a meltdown, they’ve decided to flood the containment vessel with salt water and boric acid. The water, as always, is intended to cool the reactor. The salt will corrode all the metal in the reactor over time, so this move means they’ve decided that the number 1 reactor is a loss, which probably has as much to do with the reactor’s age as anything else. The boric acid, on the other hand, is intended to slow the chain reaction further. As the result of a chemical reaction, hydrogen gas began to build up. Hydrogen gas being very flammable, this buildup caused the explosion.It is important to note that according to experts (I’m going with David Lochbaum who was cited in the New York Times) this happened in the turbine hall, NOT in the containment vessel where the nuclear fuel is. A number of alarmists have suggested that the fact that it happened outside of the containment vessel means there is a leak, but this doesn’t seem to be the case to me. There are two general designs of boiling water reactors: in one the steam that is produced by water being exposed to the core is used to turn the turbines that produce electricity directly, and in the other there is an intermediary heat exchange so that the irradiated water isn’t used to turn the turbines. Presumably (and I don’t know this to be true, but it seems likely), this reactor is of the former design. If this is the case, the turbine hall is constantly exposed to irradiated gases and so can be used to store gases in case of an emergency. Of course, this is all a bit of guess work because I don’t have any special knowledge and am relying on news reports and my less than technical understanding of reactor design.The explosion was quite alarming, but it did not damage the containment vessel as far as anyone can tell. All of the really nasty stuff remains safely tucked away in many tons of steel and concrete. According to reports, the explosion did not increase the amount of radiation present outside of the plant. I’m not entirely clear on how this could be given that the turbine hall likely housed a fair bit of radiation. …”
http://bellum.stanfordreview.org/?p=3126
http://www.japannuclear.com/nuclearpower/program/location.html
Fukushima nuclear plant blast puts Japan on high alert
“..Japan is battling to stave off a nuclear disaster after an explosion at a north-eastern nuclear plant in the wake of the enormous earthquake and tsunami.
It is feared that 1,300 people died in Friday’s double disaster, most being killed as the wall of mud and water engulfed buildings, roads and vehicles, Japanese media reported. But the priority now is to tackle the crisis at the power plant. …”
http://www.guardian.co.uk/world/2011/mar/12/fukushima-nuclear-blast-japan-alert
Nuclear Power Plants and Earthquakes
“…
-
Japanese, and most other, nuclear plants are designed to withstand earthquakes, and in the event of major earth movement, to shut down safely.
-
In 1995, the closest nuclear power plants, some 110 km north of Kobe, were unaffected by the severe Kobe-Osaka earthquake, but in 2004, 2005, 2007 and 2009 Japanese reactors shut down automatically due to ground acceleration exceeding their trip settings.
-
In 1999, three nuclear reactors shut down automatically during the devastating Taiwan earthquake, and were restarted two days later.
Design criteriaNuclear facilities are designed so that earthquakes and other external events will not jeopardise the safety of the plant. In France for instance, nuclear plants are designed to withstand an earthquake twice as strong as the 1000-year event calculated for each site. It is estimated that, worldwide, 20% of nuclear reactors are operating in areas of significant seismic activity.Because of the frequency and magnitude of earthquakes in Japan, particular attention is paid to seismic issues in the siting, design and construction of nuclear power plants. The seismic design of such plants is based on criteria far more stringent than those applying to non-nuclear facilities. Power reactors are also built on hard rock foundations (not sediments) to minimise seismic shaking.Japanese nuclear power plants are designed to withstand specified earthquake intensities evident in ground motion. These used to be specified as S1 and S2, but now simply Ss, in Gal units. The plants are fitted with seismic detectors. If these register ground motions of a set level (formerly 90% of S1), systems will be activated to automatically bring the plant to an immediate safe shutdown. The logarithmic Richter magnitude scale (or more precisely the Moment Magnitude Scale more generally used today) measures the overall energy released in an earthquake, and there is not always a good correlation between that and intensity (ground motion) in a particular place. Japan has a seismic intensity scale in shindo units 0 to 7, with weak/strong divisions at levels 5 & 6, hence ten levels. This describes the surface intensity at particular places, rather than the magnitude of the earthquake itself.
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