SUBHEAD: Just when you thought is was safe to forget about the Fukushima Dai Ichi nuclear disaster.
By William Boardman on 12 July 2013 for Hawaii News Daily -
(http://hawaiinewsdaily.com/2013/07/fukushima-spiking/)
Image above: Gray and silver storage tanks filled with radioactive wastewater are sprawling over the grounds of the Fukushima Daiichi plant. From (http://www.nytimes.com/2013/04/30/world/asia/radioactive-water-imperils-fukushima-plant.html).
Bad as the situation is at Fukushima, it’s gotten worse.
Perhaps you’ve heard that radiation levels of the water leaving the Fukushima, Japan, nuclear power plane and flowing into the Pacific Ocean have risen by roughly 9,000 per cent. Turns out, that’s probably putting a good face on it.
By official measurement, the water coming out of Fukushima is currently 90,000 times more radioactive than officially “safe” drinking water.
These are the highest radiation levels measured at Fukusmima since March 2011, when an earthquake-triggered tsunami destroyed the plant’s four nuclear reactors, three of which melted down.
As with all nuclear reporting, precise and reliable details are hard to come by, but the current picture as of July 10 seems to be something like this:
• On July 5, radiation levels at Fukushima were what passes for “normal,” which means elevated and dangerous, but stable, according to measurements by the owner, the Tokyo Electric Power Company (TEPCO).
• On July 8, radiation levels had jumped about 90 times higher, as typically reported. TEPCO had no explanation for the increase.
• On July 9, radiation levels were up again from the previous day, but at a slower rate, about 22 per cent. TEPCO still had no explanation.
• On July 10, Japan’s Nuclear Regulation Authority (NRA) issued a statement saying that the NRA strongly suspects the radioactive water is coming from Fukushima’s Reactor #1 and is going into the Pacific.
We Must Do Something
“We must find the cause of the contamination . . . and put the highest priority on implementing countermeasures,” NRA Chairman Shunichi Tanaka told an NRA meeting, according to Japan Times.
As for TEPCO, the paper reported, “The utility has claimed it has detected ‘no significant impact’ on the environment.”
“in the SNAFU sense of ‘Normal’”
Neither the NRA nor TEPCO has determined why the level of radioactivity has been increasing. Both characterize the increase as a “spike,” but so far this is a “spike” that has not yet started to come down.
Here’s another perspective on the same situation:
• 10 becquerels per liter – The officially “safe” level for radioactivity in drinking water, as set by the NRA.
A becquerel is a standard scientific measure of radioactivity, similar in some ways to a rad or a rem or a roentgen or a sievert or a curie, but not equivalent to any of them. But you don’t have to understand the nuances of nuclear physics to get a reasonable idea of what’s going on in Fukushima. Just keep the measure of that safe drinking water in mind, that liter of water, less than a quart, with 10 becquerels of radioactivity.
• 60 becquerels per liter – For nuclear power plants, the safety limit for drinking water is 60 becquerels, as set by the NRA, with less concern for nuclear plant workers than ordinary civilians.
Nobody Knows If It Will Get Worse
The water flow through the Fukushima accident site is substantial and constant, both from groundwater and from water pumped into the reactors and fuel pools to prevent further meltdowns.
In an effort to prevent the water from reaching the ocean, TEPCO is building what amounts to a huge, underground dike – “a deeply sunken coastal containment wall.” The NRA is calling on TEPCO to finish the project before its scheduled 2015 completion date.
Meanwhile, radiation levels remain high and no one knows for sure how to bring them down, or even if they can be brought down by any means other than waiting however long it takes.
TEPCO's Shakey Plan
SUBHEAD: TEPCO's plan to halt new spread of radioactive water based on shaky theory.
Image above: The former boss of Fukushima nuclear plant Masao Yoshida, center, who stayed at his post to try to control reactors after the 2011 tsunami, has died of cancer. From (http://www.news.com.au/world-news/fukushima-radioactive-groundwater-rises/story-fndir2ev-1226676769174).
Masao Yoshida, the man who led the life-risking battle at Japan's crippled nuclear power plant when it was spiraling into meltdowns, died Tuesday of cancer of the esophagus. He was 58.
Tokyo Electric Power Co. spokesman Yoshimi Hitosugi said Yoshida died at a Tokyo hospital. TEPCO officials said his illness was not related to radiation exposure.
Yoshida led efforts to stabilize the Fukushima Dai-ichi nuclear power plant after the March 11, 2011, earthquake and tsunami knocked out its power and cooling systems, causing triple meltdowns and massive radiation leaks.
Recalling the first few days when the three reactors suffered meltdowns in succession, Yoshida later said: "There were several instances when I thought we were all going to die here. I feared the plant was getting out of control and we would be finished."
Yoshida was an outspoken, tall man with a loud voice who wasn't afraid of talking back to higher-ups and was known to his workers as a caring figure. Even then-Prime Minister Naoto Kan, who was extremely frustrated by TEPCO's initial lack of information and slow handling, said after meeting him that Yoshida could be trusted.
On March 12, after Unit 1 reactor building exploded following a meltdown, Yoshida kept pumping in sea water into the reactor to cool it, ignoring an order from the TEPCO headquarters to stop doing so as Kan feared a possibility of sea water triggering a fission chain reaction. Yoshida was initially reprimanded for disobeying the order from above, but later praised for his judgment that eventually helped keep the reactor from turning worse.
"I bow deeply in respect to his leadership and decisiveness," Kan said in his Twitter entry Tuesday.
Kunio Yanagida, former member of a government-commissioned accident probe panel who interviewed Yoshida for 10 hours, said his death is a major loss for future investigations into the disaster at the plant, which hasn't been fully examined due to high levels of radiation.
Yoshida studied nuclear engineering at the Tokyo Institute of Technology and joined TEPCO in 1979. He worked in the company's nuclear department before landing a top job at the Fukushima Dai-ichi a year before the crisis.
Yoshida stepped down as plant chief in December 2011, citing the cancer, after workers had begun to bring the plant under control.
Yoshida had brought workers together and kept their spirits up to survive the crisis, and had expressed hopes of returning to work for Fukushima's recovery even after falling ill, TEPCO President Naomi Hirose said.
"He literally put his life at risk in dealing with the accident," Hirose said in a statement. "We keep his wishes to our heart and do utmost for the reconstruction of Fukushima, which he tried to save at all cost."
Leak into Pacific
SUBHEAD: Radioactive water from Fukushima Dai Ichi nuclear plant likely leaking into Pacific Ocean.
By Mari Yamaguchi on 10 July 2010 for NBC News -
(http://www.nbcnews.com/id/52437806/ns/us_news-environment/#.UeTqaFOihwk)
Japan's nuclear regulator says radioactive water from the crippled Fukushima power plant is probably leaking into the Pacific Ocean, a problem long suspected by experts but denied by the plant's operator.
Officials from the Nuclear Regulation Authority said a leak is "strongly suspected" and urged plant operator Tokyo Electric Power Co. to determine where the water may be leaking from and assess the environmental and other risks, including the impact on the food chain. The watchdog said Wednesday it would form a panel of experts to look into ways to contain the problem.
The watchdog's findings underscore TEPCO's delayed response in dealing with a problem that experts have long said existed. On Wednesday, the company continued to raise doubts about whether a leak exists.
TEPCO spokesman Noriyuki Imaizumi said the increase in cesium levels in monitoring well water samples does not necessarily mean contaminated water from the plant is leaking to the ocean. TEPCO was running another test on water samples and suspects earlier spikes might have been caused by cesium-laced dust slipping into the samples, he said. But he said TEPCO is open to the watchdog's suggestions to take safety steps.
The Fukushima Dai-ichi plant was ravaged by the March 2011 earthquake and tsunami, and TEPCO has used massive amounts of water to cool the damaged reactors since then. Repeated leaks of the contaminated water stored on site have hampered decommissioning efforts.
Marine biologists have warned that the radioactive water may be leaking continuously into the sea from underground, citing high radioactivity in fish samples taken near the plant.
Since May, TEPCO has reported spikes in cesium levels in underground water collected from a coastal observation pit, while the water-soluble element strontium showed high levels in seawater samples taken in areas just off the coast of the plant. The company says most of the contamination has been there since the 2011 accident.
TEPCO has said it has detected "no significant impact" on the environment. It says cesium tends to be absorbed in the soil, and denies water contaminated with that element reached the sea.
But the Nuclear Regulation Authority said Wednesday that samples from both the pit water and coastal seawater indicated that contaminated underground water likely had reached the sea.
Watchdog chairman Shunichi Tanaka said he thinks that the seawater contamination has been happening since the accident, but that it was worst early in the crisis.
"What's most important is to minimize the leak to the outside and reduce the impact on the human society," he said.
Most fish and seafood from along the Fukushima coast are barred from the domestic market and from being exported. Seafood caught north and south of Fukushima are regularly tested for radiation to make sure they are safe for consumption. In the wider ocean, the contaminated water becomes too diluted to be harmful.
The safety of fish and other foods from around Fukushima remains a concern among ordinary Japanese, who are among the world's highest per capita consumers of seafood.
TEPCO says it has taken steps to prevent seawater contamination but that it is impossible to completely prevent the contamination from spreading.
Atsunao Marui, underground water expert at the National Institute of Advanced Industrial Science and Technology, said there is a possibility of new leaks from reactor buildings. He said TEPCO will have to expand its seawater sampling and its investigation of the underground water system to assess the extent of possible contamination.
"It is important to apply several layers of protection," he told NHK television.
The plant still runs on jury-rigged systems to cool the reactors, and managing the contaminated water and its storage has been a chronic headache.
"When something unexpected happens, we can only take stopgap measures, which shows how unstable Fukushima Dai-ichi still is," Tanaka said. "Given the situation, we can only use the best of our wisdom and do what we can."
Tainted Flow
SUBHEAD: An unrelenting flow of radioactice water is the latest crisis at Japan Fukushima nuclear plant.
By Martin Fackler on 29 April 2013 for the New York Times -
(http://www.nytimes.com/2013/04/30/world/asia/radioactive-water-imperils-fukushima-plant.html)
Two years after a triple meltdown that grew into the world’s second worst nuclear disaster, the Fukushima Daiichi nuclear power plant is faced with a new crisis: a flood of highly radioactive wastewater that workers are struggling to contain.
Groundwater is pouring into the plant’s ravaged reactor buildings at a rate of almost 75 gallons a minute. It becomes highly contaminated there, before being pumped out to keep from swamping a critical cooling system. A small army of workers has struggled to contain the continuous flow of radioactive wastewater, relying on hulking gray and silver storage tanks sprawling over 42 acres of parking lots and lawns. The tanks hold the equivalent of 112 Olympic-size pools.
But even they are not enough to handle the tons of strontium-laced water at the plant — a reflection of the scale of the 2011 disaster and, in critics’ view, ad hoc decision making by the company that runs the plant and the regulators who oversee it. In a sign of the sheer size of the problem, the operator of the plant, Tokyo Electric Power Company, or Tepco, plans to chop down a small forest on its southern edge to make room for hundreds more tanks, a task that became more urgent when underground pits built to handle the overflow sprang leaks in recent weeks.
“The water keeps increasing every minute, no matter whether we eat, sleep or work,” said Masayuki Ono, a general manager with Tepco who acts as a company spokesman. “It feels like we are constantly being chased, but we are doing our best to stay a step in front.”
While the company has managed to stay ahead, the constant threat of running out of storage space has turned into what Tepco itself called an emergency, with the sheer volume of water raising fears of future leaks at the seaside plant that could reach the Pacific Ocean.
That quandary along with an embarrassing string of mishaps — including a 29-hour power failure affecting another, less vital cooling system — have underscored an alarming reality: two years after the meltdowns, the plant remains vulnerable to the same sort of large earthquake and tsunami that set the original calamity in motion.
There is no question that the Fukushima plant is less dangerous than it was during the desperate first months after the accident, mostly through the determined efforts of workers who have stabilized the melted reactor cores, which are cooler and less dangerous than they once were.
But many experts warn that safety systems and fixes at the plant remain makeshift and prone to accidents.
The jury-rigged cooling loop that pours water over the damaged reactor cores is a mazelike collection of pumps, filters and pipes that snake two and a half miles along the ground through the plant. And a pool for storing used nuclear fuel remains perched on the fifth floor of a damaged reactor building as Tepco struggles to move the rods to a safer location.
The situation is worrisome enough that Shunichi Tanaka, a longtime nuclear power proponent who is the chairman of the newly created watchdog Nuclear Regulation Authority, told reporters after the announcement of the leaking pits that “there is concern that we cannot prevent another accident.”
A growing number of government officials and advisers now say that by entrusting the cleanup to the company that ran the plant before the meltdowns, Japanese leaders paved the way for a return to the insider-dominated status quo that prevailed before the disaster.
Even many scientists who acknowledge the complexity of cleaning up the worst nuclear disaster since Chernobyl fear that the water crisis is just the latest sign that Tepco is lurching from one problem to the next without a coherent strategy.
“Tepco is clearly just hanging on day by day, with no time to think about tomorrow, much less next year,” said Tadashi Inoue, an expert in nuclear power who served on a committee that drew up the road map for cleaning up the plant.
But the concerns extend well beyond Tepco. While doing a more rigorous job of policing Japan’s nuclear industry than regulators before the accident, the Nuclear Regulation Authority has a team of just nine inspectors to oversee the more than 3,000 workers at Fukushima.
And a separate committee created by the government to oversee the cleanup is loaded with industry insiders, including from the Ministry of Trade, in charge of promoting nuclear energy, and nuclear reactor manufacturers like Toshiba and Hitachi. The story of how the Fukushima plant ended up swamped with water, critics say, is a cautionary tale about the continued dangers of leaving decisions about nuclear safety to industry insiders,
See also:
Ea O Ka Aina: Fukushima & Hypothyroidism in Hawaii 4/1/13
Ea O Ka Aina: Out on a Limb 6/3/13
Ea O Ka Aina: The Weakest Link 10/2/12
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By William Boardman on 12 July 2013 for Hawaii News Daily -
(http://hawaiinewsdaily.com/2013/07/fukushima-spiking/)
Image above: Gray and silver storage tanks filled with radioactive wastewater are sprawling over the grounds of the Fukushima Daiichi plant. From (http://www.nytimes.com/2013/04/30/world/asia/radioactive-water-imperils-fukushima-plant.html).
Bad as the situation is at Fukushima, it’s gotten worse.
Perhaps you’ve heard that radiation levels of the water leaving the Fukushima, Japan, nuclear power plane and flowing into the Pacific Ocean have risen by roughly 9,000 per cent. Turns out, that’s probably putting a good face on it.
By official measurement, the water coming out of Fukushima is currently 90,000 times more radioactive than officially “safe” drinking water.
These are the highest radiation levels measured at Fukusmima since March 2011, when an earthquake-triggered tsunami destroyed the plant’s four nuclear reactors, three of which melted down.
As with all nuclear reporting, precise and reliable details are hard to come by, but the current picture as of July 10 seems to be something like this:
• On July 5, radiation levels at Fukushima were what passes for “normal,” which means elevated and dangerous, but stable, according to measurements by the owner, the Tokyo Electric Power Company (TEPCO).
• On July 8, radiation levels had jumped about 90 times higher, as typically reported. TEPCO had no explanation for the increase.
• On July 9, radiation levels were up again from the previous day, but at a slower rate, about 22 per cent. TEPCO still had no explanation.
• On July 10, Japan’s Nuclear Regulation Authority (NRA) issued a statement saying that the NRA strongly suspects the radioactive water is coming from Fukushima’s Reactor #1 and is going into the Pacific.
We Must Do Something
“We must find the cause of the contamination . . . and put the highest priority on implementing countermeasures,” NRA Chairman Shunichi Tanaka told an NRA meeting, according to Japan Times.
As for TEPCO, the paper reported, “The utility has claimed it has detected ‘no significant impact’ on the environment.”
“in the SNAFU sense of ‘Normal’”
Neither the NRA nor TEPCO has determined why the level of radioactivity has been increasing. Both characterize the increase as a “spike,” but so far this is a “spike” that has not yet started to come down.
Here’s another perspective on the same situation:
• 10 becquerels per liter – The officially “safe” level for radioactivity in drinking water, as set by the NRA.
A becquerel is a standard scientific measure of radioactivity, similar in some ways to a rad or a rem or a roentgen or a sievert or a curie, but not equivalent to any of them. But you don’t have to understand the nuances of nuclear physics to get a reasonable idea of what’s going on in Fukushima. Just keep the measure of that safe drinking water in mind, that liter of water, less than a quart, with 10 becquerels of radioactivity.
• 60 becquerels per liter – For nuclear power plants, the safety limit for drinking water is 60 becquerels, as set by the NRA, with less concern for nuclear plant workers than ordinary civilians.
- 60-90 becquerels per liter – For waste water at nuclear power plants, the NRA sets a maximum standard of 90 becquerels per liter for Cesium-137 and 60 becquerels per liter of Cesium-134. At some of Fukushima’s monitoring wells, radiation levels were in fractions of a becquerel on July 8 and 9. At the well (or wells) that are proving problematical, TEPCO has provided no baseline readings.
- 9,000 becquerels per liter – On July 8, according to TEPCO, the company measured radioactive Cesium-134 at 9,000 becquerels per liter. Since TEPCO characterized this as 90 times higher than on July 5, the implication is that the earlier reading (about 100) was less than twice as toxic as the allowable limit and only 10 times more toxic than drinking water for civilians.
- 11,000 becquerels per liter – TEPCO’s measurement of Cesium-134 on July 9.
- 18,000 becquerels per liter – TEPCO measurement of Cesium-137 on July 8.
- 22,000 becquerels per liter – TEPCO’s measurement of Cesium-137 on July 9.
- 900,000 becquerels per liter – TEPCO’s measurement of the total radioactivity in the water leaking from Reactor #1.
Nobody Knows If It Will Get Worse
The water flow through the Fukushima accident site is substantial and constant, both from groundwater and from water pumped into the reactors and fuel pools to prevent further meltdowns.
In an effort to prevent the water from reaching the ocean, TEPCO is building what amounts to a huge, underground dike – “a deeply sunken coastal containment wall.” The NRA is calling on TEPCO to finish the project before its scheduled 2015 completion date.
Meanwhile, radiation levels remain high and no one knows for sure how to bring them down, or even if they can be brought down by any means other than waiting however long it takes.
TEPCO's Shakey Plan
SUBHEAD: TEPCO's plan to halt new spread of radioactive water based on shaky theory.
By Shunsuke Kimura on 13 July 2013 for the Asahi Shimbun -
(http://ajw.asahi.com/article/0311disaster/fukushima/AJ201307130066)
Image above: Gray and silver storage tanks filled with radioactive wastewater are sprawling over the grounds of the Fukushima Daiichi plant. From (http://www.nytimes.com/2013/04/30/world/asia/radioactive-water-imperils-fukushima-plant.html).
Tokyo Electric Power Co. has started taking measures to contain highly radioactive groundwater at the Fukushima No. 1 nuclear plant, but its strategy is based on a theory that is disputed by industry experts.
TEPCO insists that recently detected radioactive substances originated during the early stages of the disaster in 2011, and it is setting up barriers near the area of the initial water leak problems.
However, even the Nuclear Regulation Authority (NRA) says it is currently impossible to pinpoint where the latest leaks are coming from. Some say the leakage could be anywhere within the intricate system to cool the melted reactors and the underground maze of pipes at the plant site.
The utility’s measures, intended to prevent the underground radioactive water from spilling into the sea, could end up exacerbating the problem, some experts have warned.
The efforts to locate the cause of the leaks and prevent their further spread started more than a month after the problem was detected. Contaminated water is already believed to be draining into the sea.
On July 12, TEPCO said the No. 3 observation well at the plant produced a total reading of 1,400 becquerels of radioactive substances that emit beta rays, including strontium, per liter of water sampled on the previous day. No radioactivity had been detected in the No. 3 well a week earlier.
The No. 3 well is about 200 meters south of the No. 1 well, where high radioactive levels have been detected for some time.
Water sampled on July 8 from another well, 21 meters seaward of the No. 1 well, produced a record 630,000 becquerels of tritium, a radioactive isotope of hydrogen. That level is about 10 times higher than the legal safety limit.
The latest developments date back to late May, when water from the No. 1 well, on the seaside of the No. 2 reactor turbine building, produced high levels of radioactive substances. The readings were 500,000 becquerels of tritium per liter, or eight times the legal limit, and 1,000 becquerels of strontium per liter, or 30 times the legal limit.
TEPCO had earlier dug a number of observation wells to check for any new influx of radioactive water into the sea because seaborne levels of radioactive cesium had been slow to decline.
After the spread of radioactive substances was confirmed, TEPCO rushed to dig four additional observation wells near the No. 1 well. It also began analyzing seawater north of the water intakes for the reactors.
High radioactivity levels continue to be detected in the observation wells. TEPCO officials said they need more data to determine how the radioactive materials have been spreading.
But the plant operator believes it knows the origin of these substances. According to TEPCO, the materials represent the spread of highly radioactive water that leaked during the early phase of the 2011 nuclear disaster and have since permeated the ground.
Toyoshi Fuketa, a commissioner for the NRA, emphasized during a July 10 meeting that the origin of the leaks remains an open question.
“We have yet to learn in the first place if the spread represents leaks during the early phase of the disaster that subsequently remained stagnant, or if the spread represents leaks that came out later, and whether such leaks continue to this day,” Fuketa said.
NRA officials said the nuclear watchdog plans to soon set up a task force and begin efforts to identify the cause and block a further spread of the radioactive water.
During the chaotic early stages of the nuclear disaster, which began after the Great East Japan Earthquake and tsunami struck the plant on March 11, 2011, water used to cool the overheating reactors flowed into the basements of the reactor buildings. The highly radioactive water eventually entered underground pits for pipes and power cables seaward of the turbine buildings.
In April 2011, some of that water leaked from the end of a No. 2 reactor pit and flowed into the port at the plant via a water intake. Radioactive water also escaped from the end of a No. 3 reactor pit in a similar manner the following month.
At the time, TEPCO blocked the leaks by injecting concrete and liquid glass into the pit ends.
The company says the recently detected substances came from the early spread of this radioactive water.
According to TEPCO figures, the No. 2 reactor pits and the No. 3 reactor pits currently hold about 5,000 tons and 6,000 tons, respectively, of highly radioactive water.
However, industry experts say they cannot rule out the possibility that the radioactive materials detected in the wells derive from water that has leaked elsewhere and mixed with groundwater.
After high radioactive levels were found in the No. 1 observation well, TEPCO on July 8 began work to inject a water-sealing agent into the ground near a levee on the seaside of the No. 2 reactor turbine building as a stopgap measure to prevent leaks to sea. It plans to create a two-layered wall by the end of July, TEPCO officials said.
But waterproofing the levee could simply divert the flow of groundwater on the seaside of the turbine building, leading to a spread of radioactive contamination to unforeseen locations, according to some industry experts.
TEPCO is also considering pumping up radioactive water from the pits and funneling it into decontamination devices as part of efforts to dispose of the water.
However, the pits are connected with the turbine buildings, meaning that pumping up the radioactive water would only result in more water coming in from the turbine buildings.
Given the high radiation levels on the plant site, devising a method to block the water flow between the pits and the turbine buildings is expected to pose a major challenge.
SUBHEAD: Maseo Yoshida died Tuesday of cancer of the esophagus after leading team that kept Fukushima from even further out of control.
Former Fukushima Chief dies of cancer
By Mari Yamaguchi on 9 July 2013 for U-T San Diego -
(http://www.utsandiego.com/news/2013/jul/09/former-chief-of-fukushima-nuclear-plant-has-died)
Image above: Gray and silver storage tanks filled with radioactive wastewater are sprawling over the grounds of the Fukushima Daiichi plant. From (http://www.nytimes.com/2013/04/30/world/asia/radioactive-water-imperils-fukushima-plant.html).
Tokyo Electric Power Co. has started taking measures to contain highly radioactive groundwater at the Fukushima No. 1 nuclear plant, but its strategy is based on a theory that is disputed by industry experts.
TEPCO insists that recently detected radioactive substances originated during the early stages of the disaster in 2011, and it is setting up barriers near the area of the initial water leak problems.
However, even the Nuclear Regulation Authority (NRA) says it is currently impossible to pinpoint where the latest leaks are coming from. Some say the leakage could be anywhere within the intricate system to cool the melted reactors and the underground maze of pipes at the plant site.
The utility’s measures, intended to prevent the underground radioactive water from spilling into the sea, could end up exacerbating the problem, some experts have warned.
The efforts to locate the cause of the leaks and prevent their further spread started more than a month after the problem was detected. Contaminated water is already believed to be draining into the sea.
On July 12, TEPCO said the No. 3 observation well at the plant produced a total reading of 1,400 becquerels of radioactive substances that emit beta rays, including strontium, per liter of water sampled on the previous day. No radioactivity had been detected in the No. 3 well a week earlier.
The No. 3 well is about 200 meters south of the No. 1 well, where high radioactive levels have been detected for some time.
Water sampled on July 8 from another well, 21 meters seaward of the No. 1 well, produced a record 630,000 becquerels of tritium, a radioactive isotope of hydrogen. That level is about 10 times higher than the legal safety limit.
The latest developments date back to late May, when water from the No. 1 well, on the seaside of the No. 2 reactor turbine building, produced high levels of radioactive substances. The readings were 500,000 becquerels of tritium per liter, or eight times the legal limit, and 1,000 becquerels of strontium per liter, or 30 times the legal limit.
TEPCO had earlier dug a number of observation wells to check for any new influx of radioactive water into the sea because seaborne levels of radioactive cesium had been slow to decline.
After the spread of radioactive substances was confirmed, TEPCO rushed to dig four additional observation wells near the No. 1 well. It also began analyzing seawater north of the water intakes for the reactors.
High radioactivity levels continue to be detected in the observation wells. TEPCO officials said they need more data to determine how the radioactive materials have been spreading.
But the plant operator believes it knows the origin of these substances. According to TEPCO, the materials represent the spread of highly radioactive water that leaked during the early phase of the 2011 nuclear disaster and have since permeated the ground.
Toyoshi Fuketa, a commissioner for the NRA, emphasized during a July 10 meeting that the origin of the leaks remains an open question.
“We have yet to learn in the first place if the spread represents leaks during the early phase of the disaster that subsequently remained stagnant, or if the spread represents leaks that came out later, and whether such leaks continue to this day,” Fuketa said.
NRA officials said the nuclear watchdog plans to soon set up a task force and begin efforts to identify the cause and block a further spread of the radioactive water.
During the chaotic early stages of the nuclear disaster, which began after the Great East Japan Earthquake and tsunami struck the plant on March 11, 2011, water used to cool the overheating reactors flowed into the basements of the reactor buildings. The highly radioactive water eventually entered underground pits for pipes and power cables seaward of the turbine buildings.
In April 2011, some of that water leaked from the end of a No. 2 reactor pit and flowed into the port at the plant via a water intake. Radioactive water also escaped from the end of a No. 3 reactor pit in a similar manner the following month.
At the time, TEPCO blocked the leaks by injecting concrete and liquid glass into the pit ends.
The company says the recently detected substances came from the early spread of this radioactive water.
According to TEPCO figures, the No. 2 reactor pits and the No. 3 reactor pits currently hold about 5,000 tons and 6,000 tons, respectively, of highly radioactive water.
However, industry experts say they cannot rule out the possibility that the radioactive materials detected in the wells derive from water that has leaked elsewhere and mixed with groundwater.
After high radioactive levels were found in the No. 1 observation well, TEPCO on July 8 began work to inject a water-sealing agent into the ground near a levee on the seaside of the No. 2 reactor turbine building as a stopgap measure to prevent leaks to sea. It plans to create a two-layered wall by the end of July, TEPCO officials said.
But waterproofing the levee could simply divert the flow of groundwater on the seaside of the turbine building, leading to a spread of radioactive contamination to unforeseen locations, according to some industry experts.
TEPCO is also considering pumping up radioactive water from the pits and funneling it into decontamination devices as part of efforts to dispose of the water.
However, the pits are connected with the turbine buildings, meaning that pumping up the radioactive water would only result in more water coming in from the turbine buildings.
Given the high radiation levels on the plant site, devising a method to block the water flow between the pits and the turbine buildings is expected to pose a major challenge.
SUBHEAD: Maseo Yoshida died Tuesday of cancer of the esophagus after leading team that kept Fukushima from even further out of control.
Former Fukushima Chief dies of cancer
By Mari Yamaguchi on 9 July 2013 for U-T San Diego -
(http://www.utsandiego.com/news/2013/jul/09/former-chief-of-fukushima-nuclear-plant-has-died)
Image above: The former boss of Fukushima nuclear plant Masao Yoshida, center, who stayed at his post to try to control reactors after the 2011 tsunami, has died of cancer. From (http://www.news.com.au/world-news/fukushima-radioactive-groundwater-rises/story-fndir2ev-1226676769174).
Masao Yoshida, the man who led the life-risking battle at Japan's crippled nuclear power plant when it was spiraling into meltdowns, died Tuesday of cancer of the esophagus. He was 58.
Tokyo Electric Power Co. spokesman Yoshimi Hitosugi said Yoshida died at a Tokyo hospital. TEPCO officials said his illness was not related to radiation exposure.
Yoshida led efforts to stabilize the Fukushima Dai-ichi nuclear power plant after the March 11, 2011, earthquake and tsunami knocked out its power and cooling systems, causing triple meltdowns and massive radiation leaks.
Recalling the first few days when the three reactors suffered meltdowns in succession, Yoshida later said: "There were several instances when I thought we were all going to die here. I feared the plant was getting out of control and we would be finished."
Yoshida was an outspoken, tall man with a loud voice who wasn't afraid of talking back to higher-ups and was known to his workers as a caring figure. Even then-Prime Minister Naoto Kan, who was extremely frustrated by TEPCO's initial lack of information and slow handling, said after meeting him that Yoshida could be trusted.
On March 12, after Unit 1 reactor building exploded following a meltdown, Yoshida kept pumping in sea water into the reactor to cool it, ignoring an order from the TEPCO headquarters to stop doing so as Kan feared a possibility of sea water triggering a fission chain reaction. Yoshida was initially reprimanded for disobeying the order from above, but later praised for his judgment that eventually helped keep the reactor from turning worse.
"I bow deeply in respect to his leadership and decisiveness," Kan said in his Twitter entry Tuesday.
Kunio Yanagida, former member of a government-commissioned accident probe panel who interviewed Yoshida for 10 hours, said his death is a major loss for future investigations into the disaster at the plant, which hasn't been fully examined due to high levels of radiation.
Yoshida studied nuclear engineering at the Tokyo Institute of Technology and joined TEPCO in 1979. He worked in the company's nuclear department before landing a top job at the Fukushima Dai-ichi a year before the crisis.
Yoshida stepped down as plant chief in December 2011, citing the cancer, after workers had begun to bring the plant under control.
Yoshida had brought workers together and kept their spirits up to survive the crisis, and had expressed hopes of returning to work for Fukushima's recovery even after falling ill, TEPCO President Naomi Hirose said.
"He literally put his life at risk in dealing with the accident," Hirose said in a statement. "We keep his wishes to our heart and do utmost for the reconstruction of Fukushima, which he tried to save at all cost."
Leak into Pacific
SUBHEAD: Radioactive water from Fukushima Dai Ichi nuclear plant likely leaking into Pacific Ocean.
By Mari Yamaguchi on 10 July 2010 for NBC News -
(http://www.nbcnews.com/id/52437806/ns/us_news-environment/#.UeTqaFOihwk)
Japan's nuclear regulator says radioactive water from the crippled Fukushima power plant is probably leaking into the Pacific Ocean, a problem long suspected by experts but denied by the plant's operator.
Officials from the Nuclear Regulation Authority said a leak is "strongly suspected" and urged plant operator Tokyo Electric Power Co. to determine where the water may be leaking from and assess the environmental and other risks, including the impact on the food chain. The watchdog said Wednesday it would form a panel of experts to look into ways to contain the problem.
The watchdog's findings underscore TEPCO's delayed response in dealing with a problem that experts have long said existed. On Wednesday, the company continued to raise doubts about whether a leak exists.
TEPCO spokesman Noriyuki Imaizumi said the increase in cesium levels in monitoring well water samples does not necessarily mean contaminated water from the plant is leaking to the ocean. TEPCO was running another test on water samples and suspects earlier spikes might have been caused by cesium-laced dust slipping into the samples, he said. But he said TEPCO is open to the watchdog's suggestions to take safety steps.
The Fukushima Dai-ichi plant was ravaged by the March 2011 earthquake and tsunami, and TEPCO has used massive amounts of water to cool the damaged reactors since then. Repeated leaks of the contaminated water stored on site have hampered decommissioning efforts.
Marine biologists have warned that the radioactive water may be leaking continuously into the sea from underground, citing high radioactivity in fish samples taken near the plant.
Since May, TEPCO has reported spikes in cesium levels in underground water collected from a coastal observation pit, while the water-soluble element strontium showed high levels in seawater samples taken in areas just off the coast of the plant. The company says most of the contamination has been there since the 2011 accident.
TEPCO has said it has detected "no significant impact" on the environment. It says cesium tends to be absorbed in the soil, and denies water contaminated with that element reached the sea.
But the Nuclear Regulation Authority said Wednesday that samples from both the pit water and coastal seawater indicated that contaminated underground water likely had reached the sea.
Watchdog chairman Shunichi Tanaka said he thinks that the seawater contamination has been happening since the accident, but that it was worst early in the crisis.
"What's most important is to minimize the leak to the outside and reduce the impact on the human society," he said.
Most fish and seafood from along the Fukushima coast are barred from the domestic market and from being exported. Seafood caught north and south of Fukushima are regularly tested for radiation to make sure they are safe for consumption. In the wider ocean, the contaminated water becomes too diluted to be harmful.
The safety of fish and other foods from around Fukushima remains a concern among ordinary Japanese, who are among the world's highest per capita consumers of seafood.
TEPCO says it has taken steps to prevent seawater contamination but that it is impossible to completely prevent the contamination from spreading.
Atsunao Marui, underground water expert at the National Institute of Advanced Industrial Science and Technology, said there is a possibility of new leaks from reactor buildings. He said TEPCO will have to expand its seawater sampling and its investigation of the underground water system to assess the extent of possible contamination.
"It is important to apply several layers of protection," he told NHK television.
The plant still runs on jury-rigged systems to cool the reactors, and managing the contaminated water and its storage has been a chronic headache.
"When something unexpected happens, we can only take stopgap measures, which shows how unstable Fukushima Dai-ichi still is," Tanaka said. "Given the situation, we can only use the best of our wisdom and do what we can."
Tainted Flow
SUBHEAD: An unrelenting flow of radioactice water is the latest crisis at Japan Fukushima nuclear plant.
By Martin Fackler on 29 April 2013 for the New York Times -
(http://www.nytimes.com/2013/04/30/world/asia/radioactive-water-imperils-fukushima-plant.html)
Two years after a triple meltdown that grew into the world’s second worst nuclear disaster, the Fukushima Daiichi nuclear power plant is faced with a new crisis: a flood of highly radioactive wastewater that workers are struggling to contain.
Groundwater is pouring into the plant’s ravaged reactor buildings at a rate of almost 75 gallons a minute. It becomes highly contaminated there, before being pumped out to keep from swamping a critical cooling system. A small army of workers has struggled to contain the continuous flow of radioactive wastewater, relying on hulking gray and silver storage tanks sprawling over 42 acres of parking lots and lawns. The tanks hold the equivalent of 112 Olympic-size pools.
But even they are not enough to handle the tons of strontium-laced water at the plant — a reflection of the scale of the 2011 disaster and, in critics’ view, ad hoc decision making by the company that runs the plant and the regulators who oversee it. In a sign of the sheer size of the problem, the operator of the plant, Tokyo Electric Power Company, or Tepco, plans to chop down a small forest on its southern edge to make room for hundreds more tanks, a task that became more urgent when underground pits built to handle the overflow sprang leaks in recent weeks.
“The water keeps increasing every minute, no matter whether we eat, sleep or work,” said Masayuki Ono, a general manager with Tepco who acts as a company spokesman. “It feels like we are constantly being chased, but we are doing our best to stay a step in front.”
While the company has managed to stay ahead, the constant threat of running out of storage space has turned into what Tepco itself called an emergency, with the sheer volume of water raising fears of future leaks at the seaside plant that could reach the Pacific Ocean.
That quandary along with an embarrassing string of mishaps — including a 29-hour power failure affecting another, less vital cooling system — have underscored an alarming reality: two years after the meltdowns, the plant remains vulnerable to the same sort of large earthquake and tsunami that set the original calamity in motion.
There is no question that the Fukushima plant is less dangerous than it was during the desperate first months after the accident, mostly through the determined efforts of workers who have stabilized the melted reactor cores, which are cooler and less dangerous than they once were.
But many experts warn that safety systems and fixes at the plant remain makeshift and prone to accidents.
The jury-rigged cooling loop that pours water over the damaged reactor cores is a mazelike collection of pumps, filters and pipes that snake two and a half miles along the ground through the plant. And a pool for storing used nuclear fuel remains perched on the fifth floor of a damaged reactor building as Tepco struggles to move the rods to a safer location.
The situation is worrisome enough that Shunichi Tanaka, a longtime nuclear power proponent who is the chairman of the newly created watchdog Nuclear Regulation Authority, told reporters after the announcement of the leaking pits that “there is concern that we cannot prevent another accident.”
A growing number of government officials and advisers now say that by entrusting the cleanup to the company that ran the plant before the meltdowns, Japanese leaders paved the way for a return to the insider-dominated status quo that prevailed before the disaster.
Even many scientists who acknowledge the complexity of cleaning up the worst nuclear disaster since Chernobyl fear that the water crisis is just the latest sign that Tepco is lurching from one problem to the next without a coherent strategy.
“Tepco is clearly just hanging on day by day, with no time to think about tomorrow, much less next year,” said Tadashi Inoue, an expert in nuclear power who served on a committee that drew up the road map for cleaning up the plant.
But the concerns extend well beyond Tepco. While doing a more rigorous job of policing Japan’s nuclear industry than regulators before the accident, the Nuclear Regulation Authority has a team of just nine inspectors to oversee the more than 3,000 workers at Fukushima.
And a separate committee created by the government to oversee the cleanup is loaded with industry insiders, including from the Ministry of Trade, in charge of promoting nuclear energy, and nuclear reactor manufacturers like Toshiba and Hitachi. The story of how the Fukushima plant ended up swamped with water, critics say, is a cautionary tale about the continued dangers of leaving decisions about nuclear safety to industry insiders,
See also:
Ea O Ka Aina: Fukushima & Hypothyroidism in Hawaii 4/1/13
Ea O Ka Aina: Out on a Limb 6/3/13
Ea O Ka Aina: The Weakest Link 10/2/12
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