Media coverage
Media coverage outside of Japan has subsided over the last few days. News reporting of the events in Japan had initially concentrated on the earthquake and destructive tsunami but later shifted focus on the unfolding crisis at the Fukushima plant. But as a coalition of mainly western countries began to enforce a no fly zone over Libya, reports of the ongoing crisis in Japan has dwindled.
In Asia there is greater concern with countries close to Japan concerned that they may be directly affected by a radioactive cloud coming from the nuclear plant. Exports have been halted and there have been signs of panic in some neighbouring countries as people stock up on a number of products. In China where news is carefully controlled, there have been instances of panic buying of salt as people rushed to purchase large quantities of salt. Rumours had spread through text messages and social media that the sea near to China had been affected and that iodised salt would help protect against the absorption of the radioactive isotope Iodine 131. In some areas salt ran out in shops and there were instances of profiteering [Guardian].
The panic eventually died down and many tried to return the vast quantities of salt they had purchased. Some had stocked up on enough salt to last years and in many cases had paid hugely inflated prices. But few were able to obtain refund. One Nanjing woman bought enough salt to last 4 years. "I regret it very much. I will never behave this silly anymore," she said.
Chinese authorities reacted by saying there was no immediate threat and police arrested several individuals said to be responsible for spreading false rumours. Police in Hangzhou said they arrested one man, detaining him for 10 days and imposing a fine of 500 RMB [$76]. But there was criticism that the authorities had failed to inform the public properly. "The panic [in China] perhaps could have been avoided if the governmentt had released enough reliable information," Qiu Liping, of Shanghai University said. "The public feels anxious because it doesn't receive enough scientific knowledge from day to day," the professor from the sociology department suggested [LA Times].
There were also instances of rumours spreading in the Philippines and other Asian countries. A fake text message purporting to come from the BBC, began to circulate around many Asian countries soon after the Fukushima incident began. The message suggested people take precautions against radiation spreading from the plant. "Asian countries should take necessary precautions," the message said. "If rain comes, remain indoors first 24 hours. Close doors and windows."
While this would be sensible advice, given there was a threat, the SMS also offered erroneous information. The text advised people to "Swab neck skin with betadine where thyroid area is, radiation hits thyroid first." [BBC]
Betadine is an antiseptic containing iodine. However it is used topically and would prove to be of no help in preventing the absorption of radioactive iodine. As rumours spread there were even reports that workers and school children were sent home early. It prompted the Philippines government to issue an official statement.
The disaster has also helped spread computer malware. As well as SMS scams, security firms have seen a rise in fake anti-virus and phishing attacks regarding the Japan earthquake and the tsunami disasters.
Poor information flow
The Japanese government and the Tokyo Electric Power Co. [TEPCO] have been highly criticised for it failure in providing timely and accurate information concerning the situation at the Fukushima plant. Within hours of the earthquake the government revealed there was a problem with the nuclear plant. But it was only after a blast at reactor No. 1 on the 12th March and a second one at reactor No.3 on the 14th March that the seriousness of the situation began to emerge. The authorities blamed the blast on the ignition of hydrogen, vented from the reactor core to relieve pressure and said that only a minimal amount of radiation had leaked into the atmosphere.
A major fire at reactor No.4 was also reported. This had been out of service at the time of the earthquake but a failure in the generators which pumped water around spent fuel rods stored there had resulted in them becoming exposed after overheating and boiling the water dry. The fire was brought under control but there was a second fire the following day and it is believed that plumes of radioactive particles were sent soaring into the air.
While there was valid concern surrounding reactor No.4, the situation at reactor No.3 is far more worrying. Reactor No.3 was a MOX [Mixed Oxide] reactor which uses uranium mixed with plutonium. The blast which struck the installation sent debris hundreds of metres into the air, but the government said the core containment vessel had not been breached. However, yesterday it was revealed that traces of plutonium had been found in soil surrounding the plant from samples taken a week earlier. While it cannot be confirmed with absolute certainty, it seems likely that the blast at reactor No.3 at least partly breached the containment vessel sending highly radioactive particles into the surrounding area.
It was only by the third week on 25th March that the Japanese authorities conceded there might have been containment breaches at reactors 1, 2 and 3. Satellite photographs and video captured by a Ground Self-Defense Force helicopter showed extensive damage at the Fukushima plant. White vapor, possibly steam, could be seen emanating from the buildings of reactors 2, 3, and 4. The roof of the reactor No.2 building was shown to be badly damaged but was still intact. The reactor No.3 building was largely uncovered, following the hydrogen explosion over two weeks prior. The building at reactor No.4 was extensively damaged.
On Monday this week the Japanese Nuclear Safety Commission stated that it "assumed" melted fuel rods in unit 2 had released radioactive substances into cooling water which subsequently leaked out through an unknown route to the unit 2 turbine building basement. Despite the vague information and poor explanations as to what might be happening at the plant it is clear that radiation is leaking from the Fukushima Daiichi power station.
Rising radiation levels
Increased levels of radiation have been observed over a wide area around Fukushima and with each passing day there have been disturbing reports suggesting people take precautions. Last week it was announced that milk and spinach from the Fukushima prefecture showed increased levels of radioactivity [Reuters]. The government also advised that babies should not drink tap water as far south as Tokyo after radioactive levels were said to be above normal.
There is much confusion over what level of exposure is considered safe. However, what is clear is that radiation levels have risen. Some levels have fluctuated and dropped suggesting that the source of the radiation was radioactive iodine 131 which has a short half-life. But the discovery of plutonium and caesium outside the plant is more disturbing. These highly dangerous nuclear isotopes have far longer half-lives and if ingested the risks are very real. Of course it has to be stressed that these substances have only been found close to the plant. But the spread of water and food containing these substances poses a significant danger.
Experts are most worried about three radioactive substances, iodine 131, caesium 134 and caesium 137, which can cause various types of cancer years later.
Caesium 137 is of particular concern as it can stay in the environment and potentially cause havoc for hundreds of years. It takes 30 years for this contaminant to lose its power by half, what scientists refer to as a "half-life". At this rate, it would take at least 240 years for the contaminant to exhaust all its radioactivity.
"Caesium-137 can last for hundreds of years. If exposed, one can get spasms, involuntary muscular contractions and may lose the ability to walk. It also causes infertility. High doses will also damage a person's DNA and cause cancer later," said Lee Tin-lap, an associate professor at the Chinese University's School of Biomedical Sciences in Hong Kong. Caesium 134 has a half-life of 2 years. It would take about 20 years for it to become harmless.
Milk samples in Japan have been found to contain an average of 1,210 becquerels of iodine 131 per kilogram, well over the limit of 500 becquerels imposed in the EU. And Japanese spinach has been found with an average of 10,450 becquerels of iodine 131 per kilogram, more than 5 times the EU limit. The only mitigating factor is that iodine 131 has a half-life of 8 days, and take 80 days to lose all its radioactivity, assuming there is no fresh radioactive contamination [Reuters].
It has yet to be revealed which isotopes of plutonium have been found near to Fukushima, but some reports point to three tupes being discovered [CNN]. Plutonium-244 has a half-life of about 80 million years, just long enough for the element to be found in trace quantities in nature. Plutonium 239 meanwhile has a half-life of 24,100 years and plutonium 238 has a half-life of 88 years. Other isotopes include plutonium 240, plutonium 241 and plutonium 242 having half-lives of 65,000 years, 14 years and 37 million years respectively.
Risks
Radioactive material can be carried by tiny moisture droplets in the air. It can then be directly inhaled into the lungs, get washed down by rain into the sea and into soil and eventually contaminate crops, marine life and drinking water.
Radioactive substances are dangerous because they can cause changes or mutations in DNA, which may then cause cancer. While the human body can repair DNA changes or damage, a person is only safe if the repair process happens faster than the time it takes for the damaged or mutated DNA material to replicate.
Spread of radioactive particles
While the largest readings of radioactivity have only been measured in Japan other countries have observed slight rises in background radiation. The first country to observe a spike in radiation levels was Russia which saw minute increases in Vladivostok on the 15th March less than a week after the disaster began [Reuters].
On the same day it was reported that 'minute' amounts of radiation had been detected in Tokyo, including particles of iodine and caesium [Reuters]. Some reports suggested the levels were more than 23 times normal [MarketWatch]. The following day authorities said that levels were 10 times normal but that there was no risk to health [Reuters].
But by Sunday the 20th authorities reported radioactivity in spinach and milk and the WHO spokesman raised concerns saying that contaminated food in Japan was a "serious situation" and that it was "clearly not" a localised problem.
On Tuesday 22nd March Kyodo News quoted IAEA reports suggesting radiation was measured at 1,600 times normal level 19 km from the Fukushima plant.
Out at sea the US navy had already detected rising levels and relocated its aircraft carrier the USS Ronald Reagan [CNN]. In addition they US military put out an advisory for American personnel not to enter within 80 km of the plant.
Around the world there have been 'minuscule' amounts of radioactivity detected. Many states across the United States have registered radioactivity and there are also reports of radioactive particle reaching parts of Europe.
In north-east China authorities also detected small rises in radioactivity but insisted there was no risk to health. China Radio International reported on Saturday that China had detected low levels of radioactive material iodine 131 in the air above Heilongjiang Province but said it was "harmless". On Monday this week the People's Daily said that the population were "unfazed" by the rising levels detected in Dongning, Raohe, Hulin and Fuyuan counties, which are about 1,100 km from Japan's Fukushima Daiichi nuclear plant. Four counties in Heilongjiang were not included in the report published by the Ministry of Environmental Protection. Officials meanwhile declined to tell China Daily the latest radiation levels in the four counties, the paper reported.
The Ministry of Environmental Protection insisted that the radiation posed no risk. The "Japanese nuclear incident does not affect the country's environment and public health", the ministry said.
In an attempt to further reassure the public a ministry spokesman also insisted that China's own nuclear power plants were safe. Under the headline 'China can guarantee safety of nuclear power facilities' Xinhua quoted a ministry official Tian Shujia as saying China's atomic plants were safe and the country would not shelve plans to complete 66 nuclear power plants by 2020. "There is a guarantee for the safety of China's nuclear power facilities and (China) will not abandon (its nuclear power plan) for fear of slight risks," the official said.
Outspoken voices
Amid the official statements there are a number of experts and campaign groups calling for a rethink of nuclear power. Some have also dismissed the information released by TEPCO, the IAEA and the Japanese authorities and suggested the situation is far worse than the public are being told.
One outspoken critic is Dr Christopher Busby has said the radiation being emitted by Fukushima may have exceeded that seen after the atom blast in Hiroshima [InfiniteUnknown / Rense]. Speaking on the Alex Jones show he raised concerns that although it is still an unfolding situation the global risks were significant [YouTube]. Dr Busby has spoken on several media outlets including Press TV and the BBC and even gone as far as describing authorities as being "criminally irresponsible" for downplaying the risks.
Trade winds and ocean currents could easily spread the plume of radioactive particles around the world, Dr Busby maintains. Some tracking has already been established [animation]. The spread of particles cannot be disputed. But it depends on the level of leakage. While some independent groups such as Greenpeace are starting to do their own measurements [map] the real threat and true level of contamination has yet to be properly assessed. The state of the reactors is also unclear, with contradictory statements from day to day from official sources.
The panic eventually died down and many tried to return the vast quantities of salt they had purchased. Some had stocked up on enough salt to last years and in many cases had paid hugely inflated prices. But few were able to obtain refund. One Nanjing woman bought enough salt to last 4 years. "I regret it very much. I will never behave this silly anymore," she said.
Chinese authorities reacted by saying there was no immediate threat and police arrested several individuals said to be responsible for spreading false rumours. Police in Hangzhou said they arrested one man, detaining him for 10 days and imposing a fine of 500 RMB [$76]. But there was criticism that the authorities had failed to inform the public properly. "The panic [in China] perhaps could have been avoided if the governmentt had released enough reliable information," Qiu Liping, of Shanghai University said. "The public feels anxious because it doesn't receive enough scientific knowledge from day to day," the professor from the sociology department suggested [LA Times].
There were also instances of rumours spreading in the Philippines and other Asian countries. A fake text message purporting to come from the BBC, began to circulate around many Asian countries soon after the Fukushima incident began. The message suggested people take precautions against radiation spreading from the plant. "Asian countries should take necessary precautions," the message said. "If rain comes, remain indoors first 24 hours. Close doors and windows."
While this would be sensible advice, given there was a threat, the SMS also offered erroneous information. The text advised people to "Swab neck skin with betadine where thyroid area is, radiation hits thyroid first." [BBC]
Betadine is an antiseptic containing iodine. However it is used topically and would prove to be of no help in preventing the absorption of radioactive iodine. As rumours spread there were even reports that workers and school children were sent home early. It prompted the Philippines government to issue an official statement.
The disaster has also helped spread computer malware. As well as SMS scams, security firms have seen a rise in fake anti-virus and phishing attacks regarding the Japan earthquake and the tsunami disasters.
Poor information flow
The Japanese government and the Tokyo Electric Power Co. [TEPCO] have been highly criticised for it failure in providing timely and accurate information concerning the situation at the Fukushima plant. Within hours of the earthquake the government revealed there was a problem with the nuclear plant. But it was only after a blast at reactor No. 1 on the 12th March and a second one at reactor No.3 on the 14th March that the seriousness of the situation began to emerge. The authorities blamed the blast on the ignition of hydrogen, vented from the reactor core to relieve pressure and said that only a minimal amount of radiation had leaked into the atmosphere.
A major fire at reactor No.4 was also reported. This had been out of service at the time of the earthquake but a failure in the generators which pumped water around spent fuel rods stored there had resulted in them becoming exposed after overheating and boiling the water dry. The fire was brought under control but there was a second fire the following day and it is believed that plumes of radioactive particles were sent soaring into the air.
While there was valid concern surrounding reactor No.4, the situation at reactor No.3 is far more worrying. Reactor No.3 was a MOX [Mixed Oxide] reactor which uses uranium mixed with plutonium. The blast which struck the installation sent debris hundreds of metres into the air, but the government said the core containment vessel had not been breached. However, yesterday it was revealed that traces of plutonium had been found in soil surrounding the plant from samples taken a week earlier. While it cannot be confirmed with absolute certainty, it seems likely that the blast at reactor No.3 at least partly breached the containment vessel sending highly radioactive particles into the surrounding area.
It was only by the third week on 25th March that the Japanese authorities conceded there might have been containment breaches at reactors 1, 2 and 3. Satellite photographs and video captured by a Ground Self-Defense Force helicopter showed extensive damage at the Fukushima plant. White vapor, possibly steam, could be seen emanating from the buildings of reactors 2, 3, and 4. The roof of the reactor No.2 building was shown to be badly damaged but was still intact. The reactor No.3 building was largely uncovered, following the hydrogen explosion over two weeks prior. The building at reactor No.4 was extensively damaged.
On Monday this week the Japanese Nuclear Safety Commission stated that it "assumed" melted fuel rods in unit 2 had released radioactive substances into cooling water which subsequently leaked out through an unknown route to the unit 2 turbine building basement. Despite the vague information and poor explanations as to what might be happening at the plant it is clear that radiation is leaking from the Fukushima Daiichi power station.
Rising radiation levels
Increased levels of radiation have been observed over a wide area around Fukushima and with each passing day there have been disturbing reports suggesting people take precautions. Last week it was announced that milk and spinach from the Fukushima prefecture showed increased levels of radioactivity [Reuters]. The government also advised that babies should not drink tap water as far south as Tokyo after radioactive levels were said to be above normal.
There is much confusion over what level of exposure is considered safe. However, what is clear is that radiation levels have risen. Some levels have fluctuated and dropped suggesting that the source of the radiation was radioactive iodine 131 which has a short half-life. But the discovery of plutonium and caesium outside the plant is more disturbing. These highly dangerous nuclear isotopes have far longer half-lives and if ingested the risks are very real. Of course it has to be stressed that these substances have only been found close to the plant. But the spread of water and food containing these substances poses a significant danger.
Experts are most worried about three radioactive substances, iodine 131, caesium 134 and caesium 137, which can cause various types of cancer years later.
Caesium 137 is of particular concern as it can stay in the environment and potentially cause havoc for hundreds of years. It takes 30 years for this contaminant to lose its power by half, what scientists refer to as a "half-life". At this rate, it would take at least 240 years for the contaminant to exhaust all its radioactivity.
"Caesium-137 can last for hundreds of years. If exposed, one can get spasms, involuntary muscular contractions and may lose the ability to walk. It also causes infertility. High doses will also damage a person's DNA and cause cancer later," said Lee Tin-lap, an associate professor at the Chinese University's School of Biomedical Sciences in Hong Kong. Caesium 134 has a half-life of 2 years. It would take about 20 years for it to become harmless.
Milk samples in Japan have been found to contain an average of 1,210 becquerels of iodine 131 per kilogram, well over the limit of 500 becquerels imposed in the EU. And Japanese spinach has been found with an average of 10,450 becquerels of iodine 131 per kilogram, more than 5 times the EU limit. The only mitigating factor is that iodine 131 has a half-life of 8 days, and take 80 days to lose all its radioactivity, assuming there is no fresh radioactive contamination [Reuters].
It has yet to be revealed which isotopes of plutonium have been found near to Fukushima, but some reports point to three tupes being discovered [CNN]. Plutonium-244 has a half-life of about 80 million years, just long enough for the element to be found in trace quantities in nature. Plutonium 239 meanwhile has a half-life of 24,100 years and plutonium 238 has a half-life of 88 years. Other isotopes include plutonium 240, plutonium 241 and plutonium 242 having half-lives of 65,000 years, 14 years and 37 million years respectively.
Risks
Radioactive material can be carried by tiny moisture droplets in the air. It can then be directly inhaled into the lungs, get washed down by rain into the sea and into soil and eventually contaminate crops, marine life and drinking water.
Radioactive substances are dangerous because they can cause changes or mutations in DNA, which may then cause cancer. While the human body can repair DNA changes or damage, a person is only safe if the repair process happens faster than the time it takes for the damaged or mutated DNA material to replicate.
Spread of radioactive particles
While the largest readings of radioactivity have only been measured in Japan other countries have observed slight rises in background radiation. The first country to observe a spike in radiation levels was Russia which saw minute increases in Vladivostok on the 15th March less than a week after the disaster began [Reuters].
On the same day it was reported that 'minute' amounts of radiation had been detected in Tokyo, including particles of iodine and caesium [Reuters]. Some reports suggested the levels were more than 23 times normal [MarketWatch]. The following day authorities said that levels were 10 times normal but that there was no risk to health [Reuters].
But by Sunday the 20th authorities reported radioactivity in spinach and milk and the WHO spokesman raised concerns saying that contaminated food in Japan was a "serious situation" and that it was "clearly not" a localised problem.
On Tuesday 22nd March Kyodo News quoted IAEA reports suggesting radiation was measured at 1,600 times normal level 19 km from the Fukushima plant.
Out at sea the US navy had already detected rising levels and relocated its aircraft carrier the USS Ronald Reagan [CNN]. In addition they US military put out an advisory for American personnel not to enter within 80 km of the plant.
Around the world there have been 'minuscule' amounts of radioactivity detected. Many states across the United States have registered radioactivity and there are also reports of radioactive particle reaching parts of Europe.
In north-east China authorities also detected small rises in radioactivity but insisted there was no risk to health. China Radio International reported on Saturday that China had detected low levels of radioactive material iodine 131 in the air above Heilongjiang Province but said it was "harmless". On Monday this week the People's Daily said that the population were "unfazed" by the rising levels detected in Dongning, Raohe, Hulin and Fuyuan counties, which are about 1,100 km from Japan's Fukushima Daiichi nuclear plant. Four counties in Heilongjiang were not included in the report published by the Ministry of Environmental Protection. Officials meanwhile declined to tell China Daily the latest radiation levels in the four counties, the paper reported.
The Ministry of Environmental Protection insisted that the radiation posed no risk. The "Japanese nuclear incident does not affect the country's environment and public health", the ministry said.
In an attempt to further reassure the public a ministry spokesman also insisted that China's own nuclear power plants were safe. Under the headline 'China can guarantee safety of nuclear power facilities' Xinhua quoted a ministry official Tian Shujia as saying China's atomic plants were safe and the country would not shelve plans to complete 66 nuclear power plants by 2020. "There is a guarantee for the safety of China's nuclear power facilities and (China) will not abandon (its nuclear power plan) for fear of slight risks," the official said.
Outspoken voices
Amid the official statements there are a number of experts and campaign groups calling for a rethink of nuclear power. Some have also dismissed the information released by TEPCO, the IAEA and the Japanese authorities and suggested the situation is far worse than the public are being told.
One outspoken critic is Dr Christopher Busby has said the radiation being emitted by Fukushima may have exceeded that seen after the atom blast in Hiroshima [InfiniteUnknown / Rense]. Speaking on the Alex Jones show he raised concerns that although it is still an unfolding situation the global risks were significant [YouTube]. Dr Busby has spoken on several media outlets including Press TV and the BBC and even gone as far as describing authorities as being "criminally irresponsible" for downplaying the risks.
Trade winds and ocean currents could easily spread the plume of radioactive particles around the world, Dr Busby maintains. Some tracking has already been established [animation]. The spread of particles cannot be disputed. But it depends on the level of leakage. While some independent groups such as Greenpeace are starting to do their own measurements [map] the real threat and true level of contamination has yet to be properly assessed. The state of the reactors is also unclear, with contradictory statements from day to day from official sources.
Official statements
On Saturday for example Japan said radiation at the No.2 reactor was 1 million times normal but later retracted this and said they were only 100,000 times normal. [TEPCO Japanese / TEPCO English ] is now providing constant updates, but many believe the situation is far from being under control.
The pumping of water to keep the rods cool is suffering continued setbacks as power cannot be maintained. In addition rising radiation levels at the plant is making it too dangerous for those trying to stop those rods from overheating. The latest setback engineers face is the discovery of highly radioactive water in and around the turbine building at reactor two. Radiation detectors measured the level at 1,000 millisieverts per hour and as workers are allowed an exposure of 250 millisieverts a year, raised from 100 millisieverts before the crisis, they could only be in the contaminated area for 15 minutes before reaching the maximum dose [Guardian].
This is the latest summary released by TEPCO on Tusday 29th March. An exclusion zone remains in place around the plant extending 20km in radius with a voluntarily evacuation zone for those local residents between 20km and 30km radius of the site periphery.
According to TEPCO off-site power has been connected to Units 1 through 6. Unit 1 seems stable with water containing neutron absorbing boric acid having been pumped into the reactor since 12th March. Sea water was injected on the 23rd March and replaced by freshwater on 25th March. On 24th March white smoke was seen rising from the top of the reactor building, though no explanation is given. On that same day lighting to the main control room was restored.
As regards Unit 2, TEPCO says the Reactor Core Isolation Cooling System failed on 14th March. Water injection began the same day and the company believes only a partial amount of the rods were exposed at this time. However on 15th March an "abnormal sound" was heard near the suppression chamber and the pressure inside the chamber decreased afterwards. It was determined that something happened in the suppression chamber. While sea water injection to the reactor continued, TEPCO employees and workers from other companies not in charge of injection work started tentative evacuation to a safe location. Sea water injection to the reactor continued, the company states.
On 18th March, power restored to parts of the facility. White smoke was seen to rise from the unit on 20th but had decreased by 22nd March. The pumping of sea water continued until 26th when a switch to fresh water containing boric acid was initiated. Lighting to the control room was also restored.
An explosion occurred at Unit 3 on 14th March while water injection to the reactor was underway. Four TEPCO employees and 3 workers from other companies sustained injuries and were taken to hospital. Temperatures in the the water of the spent fuel pool rose and the spraying of water from helicopters with the support of the Self Defense Force was considered. That operation on March 16th was cancelled. Pressure of the Suppression Chamber temporarily increased, but currently is stable within a certain range, TEPCO says.
On March 20th, TEPCO say they were preparing to implement measures to reduce the pressure of the reactor containment vessel and partially discharge gases containing radioactive material to the outside environment. This was not implemented however though TEPCO says they are monitoring the pressure inside the reactor constantly. In order to cool the spent fuel pool, water was sprayed by helicopters on March 17th with the cooperation of Self-Defense Forces. Water spraying continued from the ground throughout the 17th and 21th March. On Monday 21st March light gray smoke was confirmed rising from the southeast side of the 5th floor roof of Unit 3. Staff were evacuated and the spraying of water continued the following day. By the Thursday 24th March smoke had "disappeared", TEPCO said. The spraying and injection of water has continued until today [29th March].
On Saturday for example Japan said radiation at the No.2 reactor was 1 million times normal but later retracted this and said they were only 100,000 times normal. [TEPCO Japanese / TEPCO English ] is now providing constant updates, but many believe the situation is far from being under control.
The pumping of water to keep the rods cool is suffering continued setbacks as power cannot be maintained. In addition rising radiation levels at the plant is making it too dangerous for those trying to stop those rods from overheating. The latest setback engineers face is the discovery of highly radioactive water in and around the turbine building at reactor two. Radiation detectors measured the level at 1,000 millisieverts per hour and as workers are allowed an exposure of 250 millisieverts a year, raised from 100 millisieverts before the crisis, they could only be in the contaminated area for 15 minutes before reaching the maximum dose [Guardian].
This is the latest summary released by TEPCO on Tusday 29th March. An exclusion zone remains in place around the plant extending 20km in radius with a voluntarily evacuation zone for those local residents between 20km and 30km radius of the site periphery.
According to TEPCO off-site power has been connected to Units 1 through 6. Unit 1 seems stable with water containing neutron absorbing boric acid having been pumped into the reactor since 12th March. Sea water was injected on the 23rd March and replaced by freshwater on 25th March. On 24th March white smoke was seen rising from the top of the reactor building, though no explanation is given. On that same day lighting to the main control room was restored.
As regards Unit 2, TEPCO says the Reactor Core Isolation Cooling System failed on 14th March. Water injection began the same day and the company believes only a partial amount of the rods were exposed at this time. However on 15th March an "abnormal sound" was heard near the suppression chamber and the pressure inside the chamber decreased afterwards. It was determined that something happened in the suppression chamber. While sea water injection to the reactor continued, TEPCO employees and workers from other companies not in charge of injection work started tentative evacuation to a safe location. Sea water injection to the reactor continued, the company states.
On 18th March, power restored to parts of the facility. White smoke was seen to rise from the unit on 20th but had decreased by 22nd March. The pumping of sea water continued until 26th when a switch to fresh water containing boric acid was initiated. Lighting to the control room was also restored.
An explosion occurred at Unit 3 on 14th March while water injection to the reactor was underway. Four TEPCO employees and 3 workers from other companies sustained injuries and were taken to hospital. Temperatures in the the water of the spent fuel pool rose and the spraying of water from helicopters with the support of the Self Defense Force was considered. That operation on March 16th was cancelled. Pressure of the Suppression Chamber temporarily increased, but currently is stable within a certain range, TEPCO says.
On March 20th, TEPCO say they were preparing to implement measures to reduce the pressure of the reactor containment vessel and partially discharge gases containing radioactive material to the outside environment. This was not implemented however though TEPCO says they are monitoring the pressure inside the reactor constantly. In order to cool the spent fuel pool, water was sprayed by helicopters on March 17th with the cooperation of Self-Defense Forces. Water spraying continued from the ground throughout the 17th and 21th March. On Monday 21st March light gray smoke was confirmed rising from the southeast side of the 5th floor roof of Unit 3. Staff were evacuated and the spraying of water continued the following day. By the Thursday 24th March smoke had "disappeared", TEPCO said. The spraying and injection of water has continued until today [29th March].
The problems at Unit 4 did not surface until 15th March when an explosive sound was heard and damage in the 5th floor roof of Unit 4 reactor building was confirmed. A fire continued to burn for at least two hours before being extinguished. However a second fire broke out on the 16th March and burned for at least 30 minutes. Water spraying was initiated at Unit 4 on the 20th March and has continued through the last week.
Unit 5 and 6 were shut down at the time of the earthquake but the cooling of the spent fuel rods was affected by power failures. On 19th March TEPCO started the Residual Heat Removal System Pump at units 5 and 6 to help cool the spent fuel pool. In order to prevent hydrogen gas from accumulating within the buildings, three holes were made in the roof of the reactor buildings.
On March 21st, 23rd to 27th, TEPCO say they detected technetium, cobalt, iodine, caesium, tellurium, barium, lanthanum and molybdenum in the seawater around the discharge canal of Units 1, 2, 3 and 4. On March 20th, 21st, 23rd to 27th, they also detected iodine, cesium, tellurium and ruthenium in the air collected at the site of Fukushima Daiichi Nuclear Power Station.
The company announced that plutonium had been detected from soil samples at the Fukushima Daiichi Nuclear Power Station which had been collected on 21st and 22nd of March. TEPCO say the concentration level of plutonium detected was same as that of under usual environment conditions and "it is thought not to be harmful to human health". On March 28th, TEPCO also stated that they had detected radioactive materials contained in the puddles found in the turbine building of Unit 1 to 4.
Despite the detailed accounts of the work ongoing at the plant there is little explanation concerning the leakages that have evidently occurred. Explanations as regards radiation levels and their threat to health are also confused and contradictory at times. TEPCO say they will "continuously endeavor to securing [sic] safety, and monitoring [sic] of the surrounding environment." [TEPCO]
Unit 5 and 6 were shut down at the time of the earthquake but the cooling of the spent fuel rods was affected by power failures. On 19th March TEPCO started the Residual Heat Removal System Pump at units 5 and 6 to help cool the spent fuel pool. In order to prevent hydrogen gas from accumulating within the buildings, three holes were made in the roof of the reactor buildings.
On March 21st, 23rd to 27th, TEPCO say they detected technetium, cobalt, iodine, caesium, tellurium, barium, lanthanum and molybdenum in the seawater around the discharge canal of Units 1, 2, 3 and 4. On March 20th, 21st, 23rd to 27th, they also detected iodine, cesium, tellurium and ruthenium in the air collected at the site of Fukushima Daiichi Nuclear Power Station.
The company announced that plutonium had been detected from soil samples at the Fukushima Daiichi Nuclear Power Station which had been collected on 21st and 22nd of March. TEPCO say the concentration level of plutonium detected was same as that of under usual environment conditions and "it is thought not to be harmful to human health". On March 28th, TEPCO also stated that they had detected radioactive materials contained in the puddles found in the turbine building of Unit 1 to 4.
Despite the detailed accounts of the work ongoing at the plant there is little explanation concerning the leakages that have evidently occurred. Explanations as regards radiation levels and their threat to health are also confused and contradictory at times. TEPCO say they will "continuously endeavor to securing [sic] safety, and monitoring [sic] of the surrounding environment." [TEPCO]
Situation "very grave"
This crisis is far from over and the Japanese prime minister has already expressed his concern. Naoto Kan said his government "will tackle the problem while in a state of maximum alert". Meanwhile Chief Cabinet Secretary Yukio Edano described the situation as "very grave" [BBC / Wikipedia].
This crisis is far from over and the Japanese prime minister has already expressed his concern. Naoto Kan said his government "will tackle the problem while in a state of maximum alert". Meanwhile Chief Cabinet Secretary Yukio Edano described the situation as "very grave" [BBC / Wikipedia].
tvnewswatch, Beijing, China
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