2011 Japanese Earthquake and Tsunami - News and Analysis

[chaanakya]

Nuclear watchdog defends its decision

Japan's nuclear safety watchdog says it sees no reason to change the zone for which the government advised residents to stay indoors or evacuate voluntarily.

The Nuclear Safety Commission made the remark to reporters on Thursday, following reports by the IAEA that radiation levels twice as high as its criterion for evacuation were detected in soil at a village outside the zone.

Commission member Seiji Shiroya said evacuation criteria in Japan are decided according to how much radiation people would be exposed to, not radiation levels in the ground. He said the IAEA's findings should be used as references, but that the commission's decision on the zone is correct.

Shiroya said the commission studies various factors, including radiation levels in the air and amounts of airborne radioactive substances taken into the body through breathing and eating.

He said the IAEA probably measured radiation on a grass surface with available equipment, but that he believes the commission's figures are more accurate when considering the effect on the human body

[chaanakya]

Gov't orders utilities to prepare for tsunami with more backups

They are instructed to secure vehicle-mounted power sources, deploy fire trucks that would supply water to the reactors, work out a procedure on how to deal with an emergency situation by using such vehicles, and carry out drills.

The measures are part of efforts to prevent a recurrence of the ongoing nuclear crisis at the plant in northeastern Japan, where the power grid and most of the emergency diesel generators were knocked out by the magnitude-9.0 quake and ensuing tsunami, resulting in the loss of the reactors’ key cooling functions.

Economy, Trade and Industry Minister Banri Kaieda said that the emergency measures are the ‘‘first step’’ to enhance safety at the country’s nuclear reactors after the quake and that the government is also working to compile a set of drastic measures.

Kaieda told a press conference that the direct causes that have worsened the situation at Fukushima Daiichi were the failure to secure emergency power sources, the loss of the reactors’ cooling functions and the failure to swiftly supply water to cool spent nuclear fuel pools.

The safety measures are intended to avoid a situation in which nuclear fuel is damaged and radioactive substances are released by ensuring ways to continuously cool reactor cores and spent fuel tanks even in the case external power is lost due to a natural disaster.

Kaieda said that he cannot tell whether the country’s worst nuclear crisis could have been prevented by preparing such emergency measures in advance, but added, ‘‘At this moment, I think we should have had at least this many backup facilities.’‘

Subject to the safety measures are 44 commercial nuclear reactors that are currently in operation, as well as the Monju prototype fast-breeder reactor, officials of the government’s Nuclear and Industrial Safety Agency said.

The agency will check by the end of April whether the required steps have been implemented, the officials said. The 10 reactors of the quake-hit Fukushima Daiichi and Daini nuclear power plants of Tokyo Electric Power Co are not counted in the 44.

Before the quake, the 54 commercial nuclear reactors were supplying around 30 percent of the total electricity generated in the country.

Kaieda said that he does not expect the emergency steps to require suspension of currently operating reactors, but noted that plant operators will have to clear the safety standards to restart reactors after their regular checkups.

[Theo_Fidel]

More than the new safety techniques the industry must spend the money to have a trained disaster response unit on stand by. Kinda like a nuclear Swat team. This business of sending in local fire fighters to spray water must end. The Nuclear swat team must have heavy equipment, robots, pumps, portable generators, etc on standby to be airlifted to the plant within the 4 hour generator window. The team must have a budget to constantly improve their equipment so human intervention can be minimized.

We need such a Swat team in India too.

[JwalaMukhi]

look at india's power consumption per head and see how much more it has grow to reach a 'developed' level - (we can discuss what is the right level, but not on this thread) [2% of not very much is indeed not very much and can be met from somewhere else]
then look at how much more capacity is required (irrespective of source) [10-20% of a huge number is a very large number of MW]

That's check. That's one way to skin the cat.
The other way is to see the competition for that 10% huge number with the projected rate for say year 2030 for nuclear route is strong. The justification for investing how much of that 10% should be nuclear versus non-conventional renewable route has to be made. Easily, again the non-conventional renewables can give a running and substantially be two to three times more than nuclear route.
The Life-time costing needs to be taken to ensure which yields maximum bang for the buck. Not just the present running day costs. Which means also accounting costs involved in actively managing spent fuel in backyard of the uber-rationalist mu. karunanidhi's home, since the risk factor from that is less than crossing a street from statistics.
While at it nuclear risk insurance will possibly come cheap for the operators, because risk factor is minimal, so they can tide over a situation in such unlikely event as union carbide's bhopal gas tragedy. This time probably, the industry does it correctly to cover the actual costs, so that Indians are not as shoddily treated as in bhopal case. After factoring in all the costs involved in doing the business a comparison can be done.
Dependence on foreign source for fuel supply is one big damper on nuclear route. That also needs to be factored in.
Once all this is done, then one can see how much of that 10% new projected power capacity needs to be invested through nuclear and non-nuclear routes.

all that said, nuclear is here, we have to learn how to better manage it rather than ignore it

Yes, after factoring in all the true cost benefit analysis, one will arrive how to better manage it so nuclear route is a good way to invest in certain Percentage of total energy requirements. No need to shun it, but a better case needs to be made without sensationalizing nuclear power.

[Amber G.]

Indication that anti-nuke-hysterics may also cause some some damage:
Swiss nuclear organisation targeted

A suspected letter bomb has exploded in the offices of the Swiss nuclear trade organisation, swissnuclear, injuring two people.
<snip>
..In response to the events at the Fukushima plant in Japan ..{read the whole article to get context ...

[chaanakya]

Can there be a silver lining to Japan's nuclear crisis?

The most remarkable thing about the response so far to the ''gempatsu shinsai'' (nuclear-earthquake disaster) that has engulfed Japan is that there are still people who think nuclear power has a future.

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

Besides the true believers, there are also those who regard nuclear energy as a necessary evil. They don't particularly like it, but they see no alternative.

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

If future generations are to say that there was a silver lining to the cloud of the Fukushima Daiichi disaster, it will be because human beings now looked beyond their recent history and chose to build a society that was not subject to catastrophic risks of human making.

(Philip White is the International Liaison Officer of the Tokyo-based Citizens' Nuclear Information Center.)

[chaanakya]

More than the new safety techniques the industry must spend the money to have a trained disaster response unit on stand by. Kinda like a nuclear Swat team. This business of sending in local fire fighters to spray water must end. The Nuclear swat team must have heavy equipment, robots, pumps, portable generators, etc on standby to be airlifted to the plant within the 4 hour generator window. The team must have a budget to constantly improve their equipment so human intervention can be minimized.

We need such a Swat team in India too.

Taisei set to introduce robots for N-cleanup

Future Perfect.

Taisei Corp. on Wednesday announced plans to introduce unmanned heavy machines to speedily clear away highly radioactive rubble at the crippled Fukushima No. 1 nuclear power plant.

The March 11 earthquake-tsunami disaster has left huge amounts of rubble at the plant, posing an obstacle to efforts to defuse the ongoing crisis. However, since the rubble is contaminated with high levels of radiation, workers cannot spend lengthy periods in cleanup efforts.

However, this dilemma could be solved by introducing remote-controlled, unmanned bulldozers, power shovels, dump trucks and other heavy machinery, said the construction company.

These machines and control systems, using wireless local area networks and global positioning systems, were developed by the Unmanned Construction System Association in Tokyo, a consortium of 15 construction and related companies.

As such unmanned machines can be used in places too dangerous for workers, they have been used at more than 100 sites including restoration work at the Mt. Fugen volcano in Nagasaki Prefecture, which erupted with large pyroclastic flows in 1991, and Hokkaido's Mt. Usu, where a volcanic eruption occurred in 2000.

After the 1979 Three Mile Island nuclear power plant accident in the United States, remote-controlled robots were used to remove nuclear fuel, do restoration work in radiation-contaminated water and measure radioactivity levels inside the plant.

Their good track record has prompted countries around the world to accelerate research and development of robots to work at nuclear facilities.

(Mar. 31, 2011)

[chaanakya]

Kan, Sarkozy agree to craft new int'l nuclear safety standards

NANJING, China (Kyodo) -- Japan and France agreed Thursday that the two countries will cooperate in crafting new international nuclear safety standards by the end of this year, following the continuing crisis at the Fukushima Daiichi nuclear power plant triggered by the devastating March 11 earthquake and ensuing tsunami.

The agreement was reached during talks in Tokyo between Prime Minister Naoto Kan and French President Nicolas Sarkozy, who became the first foreign leader to visit Japan since the twin natural disasters that obliterated northeastern coastal towns.

...................
Sarkozy, who is G-8 chair this year, said he will try to release a communique on nuclear safety at the forthcoming summit.

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

He also said that France, which relies on nuclear power for nearly 80 percent of its electricity, is committed to offering more of its expertise to help Japan contain radiation leaking out of the crippled complex, located around 220 kilometers from Tokyo.

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

France has the second highest number of nuclear power stations after the United States. Japan has the third highest number, deriving about 30 percent of its power from nuclear reactors.

Sarkozy said that nuclear power remains a viable source of energy and he believes it would be impossible to slash carbon dioxide emissions without it.

[chaanakya]

Latest casualty figures for March 11 quake, tsunami
TOKYO, March 31, Kyodo

the following are the latest casualty figures related to the earthquake and tsunami that hit northeastern and eastern Japan on March 11, according to the National Police Agency as of 9 p.m. Thursday:

Number of people killed 11,532
Number of people missing 16,441
==Kyodo

[chaanakya]

Looking forward from Fukushima By Natalie J. Goldring

the bottom line is that we have to consider the full costs of decisions about future energy sources, rather than only counting the short-term costs.

(Natalie J. Goldring is a senior fellow with the Center for Peace and Security Studies in the Edmund A. Walsh School of Foreign Service at Georgetown University in Washington.)

[chaanakya]

Five-year-old Ayumi Onodera helps distribute food at an evacuation center for earthquake and tsunami victims on Oshima island in northern Japan, on Sunday.

http://www.japantoday.com/images/size/6 ... /girl2.jpg

[Theo_Fidel]

http://www.ieer.org/comments/Fukushima_ ... -03-25.pdf

The French radiation protection authority, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), estimates the radioactive releases of iodine-131 in Japan had reached about 2.4 million curies by March 22, 2011. That is about 160,000 times the best estimate of the amount released during the TMI accident in Pennsylvania (15 curies) and about 140,000 times the maximum estimate of 17 curies. It is about 10 percent of the estimated amount released during the Chernobyl accident, according to the IRSN. Combined cesium-134 (half-life: about 2 years) and cesium-137 (half life: about 30 years) releases from Fukushima are estimated at about half-a-million curies, about 10 percent of estimated Chernobyl cesium releases. The TMI accident did not emit measurable amounts of radioactive cesium, according to the presidential commission that investigated the accident.

[Amber G.]

the bottom line is that we have to consider the full costs of decisions about future energy sources, rather than only counting the short-term costs.

Very good.. and include all sources.. consider cost of gas explosions, carbon monoxide poisonings, coal mine accidents, oil well blowouts, ityadi ityadi.
Consider data like per EPA fossil fuel exhausts still kill 24,000 people a year. ( Why does nuclear's almost perfect safety record seems to generate so more fear?)

[Amber G.]

Virtually every one I know in academic circle agrees that MSM's radiation related danger is irresponsibly exaggerated. Yet almost every media and their experts are still reporting error prone and some times out-right silly statements.

(yes it is serious but one has to consider backdrop of Earth quake etc)

Reasonable analysis : From New Scientist Below:
Risk expert: Why radiation fears are often exaggerated

What is it about nuclear energy that makes people particularly fearful?
There has been a lot of research on this. Nuclear radiation ticks all the boxes for increasing the fear factor. It is invisible, an unknowable quantity. People don't feel in control of it, and they don't understand it. They feel it is imposed upon them and that it is unnatural. It has the dread quality of causing cancer and birth defects.

Nuclear power has been staggeringly safe, but that doesn't stop people being anxious about it, just as airplanes and trains are an amazingly safe way to travel but people still worry far more about plane crashes than car crashes.

People are calling the release of radiation from the Fukushima nuclear power station in Japan a "catastrophe". Is this justified?

This is indeed a really serious event, but it has to be put in the context of the earthquake and tsunami which led to it - and which has been the direct cause of massive suffering, which is still continuing. Obviously there are threats from the nuclear power station, but they are limited and they are quantifiable. It's not a Chernobyl. Though the 1986 explosion at Chernobyl was a terrible event for many people, the lasting effects were nothing like as bad as expected.

Many governments are suspending their nuclear power projects in response to the events in Japan. Is it sensible to make these decisions in the aftermath of a disaster?

This is a tricky one. The Fukushima power station was hit by an unimaginable force. One is always surprised by these events, but one of the things you learn when you study risk is that surprising things happen. We have to expect the unexpected.

Of course, political decisions are made on the basis of how people feel. That's a politician's job perhaps, not just to respond to objective measurements of risk but to what people want. But it's good to try and keep a perspective on what the risks are for all viable alternatives, including the risk of relying on unsavoury regimes for our sources of energy.

Does this mean that fear itself is part of the problem?

One of the biggest risks from radiation is the psychological damage it causes. After events like the 1979 partial meltdown at Three Mile Island, Pennsylvania, and the Chernobyl accident, there was substantial psychological trauma, even among people who were not affected, because there is such a fear of radiation and its long-term consequences.

Would you be happy to live next to a nuclear power station?

I have been trying to think how I would feel if I were in Japan right now. Would I be rushing out of Tokyo or not? I would love to say that I would be a plucky Brit and sit there with my stiff upper lip. But it is very difficult to know how you would react, especially as people respond to the feelings of those around them. But yes, I would be happy to live next to a nuclear power station, if only they weren't such big ugly things.

Can I request Shiv (or others) to start a poll on some of these items here?

[Amber G.]

Headline more serious than "17 in serious condition in hospital"
Nuclear Rescuers: 'Inevitable Some of Them May Die Within Weeks'
Story is from mainstream, one of the most popular, news outlet, Fox.
Headline is in large fonts (see it yourself) with catchy words:

.. Inevitable..!
Die within weeks!

Of course, if you read the same story and fine prints, you see the information is from a mother of a worker who talked with her son.

For those, who would read the story, let me post few lines from the above story:

My son and his colleagues have discussed it at length and they have committed themselves to die if necessary to save the nation.
“He told me they have accepted they will all probably die from radiation sickness in the short term or cancer in the long-term.”

She how "probably" is interpreted as 'inevitable' and 'long-term' becomes "weeks" and mother's worry about her son becomes an expert forgone conclusion.
Of course, when you further read it more, you do see this:

She could not confirm if her son or other workers were already suffering from radiation sickness

Speechless! Of course, looking at the comments on the above piece, it seems, the headlines are working to fool the people. I only hope that brf readers are smarter and really pay attention.

(Added later: The story happens to be the top story from google news for me)

Essentially the same story, but slightly different headline from UK Telegraph:
Japan nuclear crisis: Fukushima 50 'expect to die'
Talk about reckless irresponsibility

[JwalaMukhi]

http://www.reuters.com/article/2011/03/ ... QH20110331

TEPCO could face compensation claims topping $130 billion if Japan's worst nuclear crisis dragged on, Bank of America-Merrill Lynch estimated this week, further fuelling expectations Japan's government will step in to save Asia's largest utility.

Liabilities for compensation claims alone could be up to 11 trillion yen ($133 billion) -- nearly four times TEPCO's equity -- if the nuclear crisis drags on for two years, an analyst at Bank of America Merrill Lynch wrote in a report.

TEPCO shares are down almost 80 percent since the disaster.

Experts, however, say a final resolution of the nuclear disaster is likely to take decades and there could be many further setbacks.

TEPCO could burn through 2 trillion yen in about a year, said CLSA equity analyst Penn Bowers, as it pays extra for fuel to run its thermal plants, among other costs.

So, probably the company will be sued out of business. This is the kind of eventuality and the cost factor that nuclear industry has to use in calculating the cost of business. Then with such liabilities and good lawyers who would sue for loss of livelihoods, nuclear industry will have tough time being competitive against non-conventional renewables. That being said, India has to watch out, because the nuclear industry may try a bhopal on Indians, without need to pick up such tabs because Indians are cheap.

Focussing on deaths will not show the magnitude of the life-time operating costs of nuclear plant. It will come out as safest option. Loss of livelihoods, unusability of large swathes of land for 2 to 3 generations are considerations that will haunt nuclear industry.

[Theo_Fidel]

WRT to the Fukushima workers..

They are the ones putting their health and safety on the line. They know what they deal with. They can characterize it how ever they want. Firefighters who go into blazes say the same all the time, that 'they expect to die.' They do it anyway. Let us honor their courage rather than casting aspersions on the risk they face.

[abhishek_sharma]

JAPAN DISASTER: Pool at Stricken Reactor #4 Holds Answers to Key Safety Questions

http://www.sciencemag.org/content/332/6025/24.full

Of all the terrible news from the crippled Fukushima Daiichi nuclear power plant, reports about the spent fuel storage pool for reactor #4 may be among the most disconcerting for scientists. The pool held the entire complement of fuel rods from the reactor's core, which had been emptied 3 months before the 11 March earthquake and tsunami struck. And yet on 15 March the building exploded, apparently fueled by hydrogen, leaving nuclear engineers to speculate about the source. Adding to the confusion are reports of fires in the pool, a worst-case scenario that had never before occurred in a working nuclear plant.

Unraveling the mysteries surrounding the #4 pool will require discovering why water levels there fell so quickly, and whether the 230 tons of spent nuclear fuel melted in addition to catching on fire. Researchers also need to quantify how much radioactive material might have been released. The events at the #4 pool could shed light on the dangers posed by spent fuel in pools at more than 350 reactors globally, and what needs to be done to assure the public that they can be operated safely.

As Science went to press, extremely high levels of radiation were hampering efforts to restore power and water lines to all six reactors at the complex. And while a possibly damaged core in reactor #3 was leaking highly radioactive water, reactor #4's pool remains among the biggest potential sources of radiation. In video released early this week, what appeared to be steam continued to billow from reactor #4's blown-out frame despite continued efforts to add water.

Hot fuel

The nuclear fuel at reactor #4 is made up of uranium pellets held in 4-meter-long tubes made of zirconium alloy. The pool holds 1331 bundles of tubes, known as assemblies; 548 were removed from the reactor in January during maintenance.

Daiichi has seven spent nuclear fuel pools: one for each of its six reactors, and a central one. They serve two main purposes: to cool the fuel, which gives off heat as a result of radioactive decay, and to shield workers and the environment from radiation. In reactors with Fukushima Daiichi's design, pools are not in sealed containment vessels but are open and accessible; operators are keenly aware of the importance of keeping water levels high. (Although the pool at reactor #3 may also have produced hydrogen, the other five pools have required constant replenishment but remained stable.)

One mystery about the #4 pool is how its water level fell so quickly. During normal operation, 7 meters of roughly 40°C water sit between the top of the fuel rods and the surface of the 1425-ton pool. The water is constantly circulated and replenished. There's little doubt that temperatures in the pool would have risen steadily after power was lost. But several scientists have independently calculated that it would take much longer than 4 days—perhaps as much as 3 weeks—for the heat of the fresh fuel in the #4 pool to evaporate or boil off the water.

Could the #4 pool's structure have been damaged in the quake or subsequent explosions or both? Among possible weak points are the large doors on the side of the pool. The doors, which allow fuel to pass underwater from the reactor into the pool, are held shut by rubber gaskets inflated by electric pumps. In 1986, at the Hatch nuclear plant near Baxley, Georgia, the water level in a spent fuel pool dropped by more than a meter after the seals were left uninflated. But engineers say that the channel between the reactor and the pool is filled with water during maintenance periods, meaning that a leak would lengthen the time it took to empty the pool. “It's surprising to me [that] the fuel became uncovered that quickly,” says Lake Barrett, a retired nuclear engineer and former U.S. Nuclear Regulatory Commission (NRC) official.

Determining the temperature of the pool has been another challenge. (It was reported to be 84°C the day before the explosion; no data have been subsequently released.) Knowing that temperatures were high enough to drive water completely from the pool could help researchers quantify how much radioactivity was released in subsequent steps. The day after the 15 March explosion, NRC Chair Gregory Jaczko said that the pool had run dry at one point, a claim that the Japanese government has disputed.

At least one fire in the pool—and possibly a second—was reported by power company officials after the explosion. Lab experiments have shown that zirconium can burn either with steam or with oxygen. Both reactions progress rapidly at roughly 800°C; the former, crucially, releases hydrogen. The hydrogen explosion at reactor #4 points to the steam reaction, which releases less energy and therefore melts the fuel more slowly. But knowing which reaction dominated could help scientists quantify how much radioactivity was released from pool #4. A 2006 study by the U.S. National Research Council said that a heat up after a loss-of-water event could melt the spent fuel, allowing the escape of volatile radionuclides, including “a substantial fraction of the cesium,” into the air.

Soil samples analyzed by the Japanese science ministry last week found cesium levels roughly equivalent to 8 million becquerels per square meter near the plant. That level, if accurate, would be higher than those found near Chernobyl. (Radioactive iodine has been found in Japanese tap water, but its 8-day half-life means that it couldn't have come from the older spent fuel in pool #4. Reactor #3 may be the source.) Scientists also don't know what fraction of the radioactive cesium released is from reactors or from spent fuel. Scientists hope more detailed isotopic measurements will shed light on the age and, therefore, the source of the radioactive particles.

Minding the pools

Some experts believe that governments and the nuclear power industry have done a poor job of sharing information on the risk of zirconium fires. Critics of NRC say that studies conducted for the agency likely contain relevant data but have been kept classified to keep the information away from terrorists. “To the extent that any experiments have been done at all, the public doesn't know about them,” says spent-fuel expert Gordon Thompson of Clark University in Worcester, Massachusetts. The National Research Council study called on NRC to “improve the sharing of pertinent information” on pool risks.

The calamity at Fukushima Daiichi has raised particular concerns about U.S. spent nuclear fuel pools, which are thought to be packed more tightly than those in Europe or Asia. “Spent nuclear fuel may be more vulnerable than we thought,” says Edwin Lyman of the Union of Concerned Scientists in Washington, D.C. The nuclear industry has added additional sprayers to pools and now mixes hot, fresh spent fuel with older fuel in the pools to redistribute the heat. But it balked at a 2008 recommendation by Jaczko—speaking in an unofficial capacity—to transfer U.S. fuel older than 5 years to dry concrete casks, where the cooled fuel is highly unlikely to catch fire. Still, the industry has begun a safety review of U.S. reactors, and NRC has launched two studies into U.S. plant safety that could lead to new rules on spent fuel.

[abhishek_sharma]

JAPAN DISASTER: Scientific Consensus on Great Quake Came Too Late

http://www.sciencemag.org/content/332/6025/22.full

Ten years ago, Koji Minoura, a geologist at Tohoku University in Sendai, and colleagues injected some science into a legendary disaster. A historical document compiled in 901 C.E. told of an earthquake in 869 C.E. that destroyed a castle town in northeastern Japan and a subsequent tsunami that inundated the surrounding area, killing 1000. Digging in rice paddies in what is now called the Sendai Plain, Minoura's team found telltale marine sediments showing that the tsunami ran as much as 4 kilometers inland. They estimated the Jogan earthquake's magnitude at 8.3 and concluded that it could recur at 1000-year intervals. “The possibility of a large tsunami striking the Sendai Plain is high,” they wrote in a 2001 article in the Journal of Natural Disaster Science.

That obscure paper is now at the center of a growing debate about how quickly scientific findings can and should influence disaster-mitigation policies. A few years before the magnitude-9.0 Tohoku earthquake struck northeastern Japan on 11 March, a scientific consensus had begun to coalesce around the idea that a Jogan-like event could happen again. But that consensus did not influence seismic risk assessments, tsunami preparedness, or a review of the hardiness of the Fukushima Daiichi nuclear power plant.

“It's necessary to communicate research findings to society,” says Yukinobu Okamura, a geologist at the Active Fault and Earthquake Research Center in Tsukuba, who led studies that independently bolstered Minoura's findings. “We tried to do that in this case, but we weren't in time.”

One lesson is that incorporating geological studies of ancient earthquakes and tsunamis into risk assessments “is essential to compensate for the limitations in the current evaluation scheme,” says Fumihiko Imamura, a tsunami engineer at Tohoku University in Sendai.

The need to revise earthquake probability analyses extends far beyond Japan. “There are other subduction zones, near Java and New Zealand, where people think there is no chance of a big quake” because they cling to old models of seismic processes, says Robert McCaffrey, a geophysicist at Portland State University in Oregon. But forecasts are generally based on studies covering the past several centuries—“not long enough for the cycle time for these big earthquakes,” he says.

Although scientists have been interrogating geologic deposits for clues to the size and frequency of major earthquakes for several decades, efforts to apply such techniques to ancient tsunamis are more recent. In the early 1990s, “many people didn't believe tsunamis left deposits,” says Joanne Bourgeois, a tsunami geologist at the University of Washington, Seattle. Minoura was among the paleo tsunami pioneers when he started digging in the Sendai Plain. Recent sediment surveys have supported his Jogan findings, while studies of accumulating crustal strain in the Sendai area hinted at the possibility of a major earthquake. Even so, before the 11 March quake some scientists “did not believe” the region was primed for a big earthquake, says Yuichiro Tanioka, a seismologist at Hokkaido University in Sapporo.

Planners and engineers began to recognize the significance of geologic research for earthquake preparedness in the late 1970s, after paleoseismic studies revealed the regular recurrence of earthquakes along the San Andreas fault in California. But paleo studies didn't directly influence public policy until the mid-1990s. An early example is the Cascadia earthquake, now known to have occurred in the subduction zone off North America's Pacific Coast in 1700. In 1986, researchers reported the first geological evidence for this massive event: a sudden drop in elevation of coastal regions, inferred from sedimentary deposits, a sign of slippage on the upper side of a subduction zone. Eight years later, a revision to the Uniform Building Code required buildings in western Washington and Oregon to be 50% more earthquake-resistant. Then in 1995, partly because of the Pacific threat, the U.S. Congress passed the National Tsunami Hazard Mitigation Program, which supports studies of tsunami risk and emergency planning.

The size and timing of the Cascadia earthquake were unclear. Those pieces of the puzzle turned up in Japan, where Kenji Satake, a seismologist now at University of Tokyo, and colleagues found Japanese accounts of a tsunami without an apparent local cause. In Nature in 1996, they pinpointed the date of the Cascadia earthquake as 26 January 1700 and estimated a magnitude of 9.0. “There is a lot of respect for [Japan's] record-keeping diligence,” says Brian Atwater, a U.S. Geological Survey geologist at the University of Washington, Seattle.

Japan's Headquarters for Earthquake Research Promotion produces seismic hazard maps for the nation; they are used to estimate potential tsunamis. The headquarters incorporates paleoseismic studies in determining earthquake risk—but only in Hokkaido, Tanioka says. Hokkaido was the last region of modern Japan settled by ethnic Japanese, and reliable records go back only to the mid-1800s, he says. Elsewhere, the agency relies on “documents allowing the estimation of earthquake frequency and scale [going] back 400 years,” Imamura says. Using those records, the earthquake research headquarters warned that the area hit by the 11 March temblor faced a 99% probability of a magnitude-7.5 earthquake occurring in the next 30 years.

Okamura and colleagues conducted more extensive surveys in the Sendai area in the mid-2000s that bolstered Minoura's original findings. According to Okamura, the earthquake research headquarters was studying whether and how to include Jogan in its risk assessment for the Tohoku region. “But the earthquake occurred before the evaluation was completed,” he says.

Any upward revision is now also too late for the Fukushima plant. The first reactor was completed in 1971, long before the Jogan event appeared on the scientific radar. Planners girded for a maximum 5.7-meter tsunami; Tokyo Electric Power Co. estimates that the tsunami that took out the backup diesel generators was 14 meters high. The company missed a chance to address the deficiency when an expert panel reviewed the plant's seismic resistance in 2008. As The Washington Post reported, Okamura told the panel about the Jogan earthquake and warned that a bigger tsunami was possible. The panel, concerned mostly about earthquake shaking, brushed aside his concerns, he asserts.

Japan and other countries will surely rethink tsunami threats—just as Minoura intends to do. Originally, he says, he tried to “simply make clear the geological process of coastal environments.” But now, “I want to meditate deeply on the future of geological work [related to] tsunamis,” he says. The Tohoku temblor should convince the scientific community and authorities that magnitude-9 earthquakes can occur anywhere along subduction zones, McCaffrey says. Like a tsunami, the effects of the 11 March Tohoku earthquake will spread far and wide.

[abhishek_sharma]

Concerns over nuclear energy are legitimate

http://www.nature.com/news/2011/110330/ ... 1549a.html

The unique and almost existential nature of the risk posed by nuclear power has had ample airing over the past three weeks, since the disaster at the Fukushima plant in Japan. Enthusiasm for a global nuclear revival has stalled — and not before time.

The scientific community could yet play a valuable part in the management of this crisis. It could help put events in perspective, and begin the process of drawing out useful regulatory and other lessons. In the United States, this has already begun, with specific suggestions for change coming from former US government science advisers Frank von Hippel and Matthew Bunn. Last week on this page, Charles Ferguson, president of the Federation of American Scientists, did likewise (see C. D. Ferguson Nature 471, 411; 2011).

Less edifying have been the nuclear experts who have popped up in the media to 'inform' the public about the crisis. Individually, their motives may be honourable, but the collective impression has been unconvincing: defensive, selective, condescending towards public fears and, in my view, ultimately counterproductive. Their combined message seems to have been: don't worry, things are under control, and Fukushima is not Chernobyl.

Well, Fukushima is certainly not Chernobyl, but some salient points about what Fukushima actually is, I would argue, deserve wider attention. All are relevant to the future deployment of nuclear power.

“The risk of nuclear power is that active human intervention has to be maintained.”
One is that Fukushima houses six reactors on one site, despite the fact that even the most basic analysis of failure modes and effects would come out resoundingly against such an arrangement. Not only are all the reactors exposed simultaneously to the same dangers — whether flood, earthquake, war or terrorist attack — but radiation release at one reactor or fuel tank could cripple recovery efforts at the others. Everyone in nuclear engineering knows this. Yet such co-siting is the central organizing principle of current nuclear-build plans in Britain, the United States and elsewhere, because the only communities that will accept new nuclear plants are those that already have them.

The second is an inherent problem with light-water reactors, including boiling-water reactors, as at Fukushima, and pressurized-water reactors (PWRs). These designs are compact and relatively inexpensive, but their potential for meltdown was once obvious enough that Britain spent 30 years trying to develop gas-cooled alternatives. But, now that PWRs are the only viable design for new nuclear build, that extensive search for a safer design seems to have been forgotten by many of those who promote a nuclear future.

A third point is the storage of spent fuel rods in pools of water at power plants. The amount of fuel held in this way continues to grow relentlessly, particularly in the United States, where the Obama administration's shelving of the Yucca Mountain waste-storage project in Nevada leaves the fuel with nowhere else to go. As in the United Kingdom, such 'interim' storage is the only likely destination for spent fuel from new reactors, ahead of promised deep disposal in an uncosted, unscheduled and uncertain underground repository.

These legitimate technical criticisms of Fukushima, and of planned nuclear build, have been largely drowned out by the flood of technical reassurance offered by nuclear scientists and engineers in the wake of the disaster. For example, reassuring soundbites offered to journalists by the London-based Science Media Centre (which is funded by a variety of scientific bodies and industries, including Nature Publishing Group) in the days immediately after the earthquake contained barely a cautionary note on how serious the situation at Fukushima was set to become. Instead, the scientific establishment and those whose careers are invested in nuclear power have sought to convince the public that 'science' supports nuclear power. Too many specialists have assured us of the general safety of nuclear power without adequately addressing specific concerns.

Some of this loyalty is deep rooted, I fear, in the development of the atomic bomb, which greatly embellished the standing of the scientific establishment with governments. Not long afterwards, many senior physicists embraced 'atoms for peace'. Having interrogated nature, and established the means to harness some of its terrible powers, they wanted to prove themselves 'useful'. Such a culture influences those who follow — and can take generations to wear off.

Costing and planning of new nuclear power stations will now be carried out in the light of three data points: Three Mile Island in 1979, Chernobyl in 1986 and Fukushima in 2011. In each case, excuses are readily made by supporters of nuclear power. For Three Mile Island, they were that radiation releases were minimal, and that a supposedly unsophisticated American public confused the accident with the plot of The China Syndrome. Communist incompetence, we are told, contributed to Chernobyl being as bad as it was. The race is now on to find a narrative that explains away the ugly reality of the Fukushima disaster. The alleged uniqueness of the earthquake and tsunami event is already emerging as the front runner.

Yet the real risk of nuclear power is that active human intervention has to be maintained, come rain, shine, war or political upheaval. That, and the threat of a downside too terrible to contemplate.

Colin Macilwain is a contributing correspondent with Nature.

[abhishek_sharma]

Lessons from the past

The Chernobyl disaster still has much to tell us about the long-term risks of low-level radiation exposure. But only if the necessary follow-up studies are supported.

http://www.nature.com/nature/journal/v4 ... 1547a.html

As the battle to make safe the Fukushima nuclear reactors continues, the political fallout is spreading across Japan and around the world. Despite reassuring early reports, it is clear that significant amounts of radioisotopes have been released from the plant, and some workers there face severe radiation exposure as they try to cool the overheated nuclear fuel. In response, several governments are reviewing the safety and future of their own nuclear programmes. Fukushima has undoubtedly strengthened the hand of those who oppose nuclear power.

The global reach of the disaster brought an echo from history last week when iodine-131 from Fukushima was detected in Ukraine — home to the Chernobyl power plant, site of the world's worst civilian nuclear disaster. A quarter of a century ago, a flawed safety test at Chernobyl triggered a massive explosion and fire that spread tonnes of radioactive material across Europe, and shredded public confidence in atomic energy.

Like Fukushima, the consequences of Chernobyl were wide ranging. In the satellite countries, resentment of Soviet handling of the disaster contributed to the fall of the Soviet Union. Thousands of children developed thyroid cancer after drinking contaminated milk. Billions of crucial dollars from the economies of Ukraine and Belarus were redirected to remediation, health care and compensation. Every day, some 3,500 workers still labour at the plant to prevent further releases, while decommissioning of the site's four reactors has barely begun. Recovering from a nuclear disaster is the task of generations: it will be another 50 years before Chernobyl is just a memory.

As we report on page 562, the pace of recovery at Chernobyl has been slowed by the reluctance of other countries to pay for it. The shattered reactor 4 still lies beneath a haphazard concrete sarcophagus, erected in the frantic months after the accident. Maintenance work keeps it secure — for now — but the walls are streaked with rust and its roof is in a poor state of repair. Engineers want to build a safe confinement arch to allow them to dismantle the reactor, at an estimated cost of US$1.4 billion.

“Recovering from a nuclear disaster is the task of generations.”
The Chernobyl Shelter Fund, managed by the European Bank for Reconstruction and Development, has so far amassed more than $800 million of that sum, from 30 donors. But funding shortfalls have delayed the project by years and the 2015 target for completion will be difficult to achieve without more money from the international community.

One immediate consequence of the Fukushima disaster should be to encourage this money to flow. Nuclear accidents have global repercussions, and public mistrust of nuclear power demands that its problems not be left to fester. It is in the world's interest to push forward with safe nuclear power — but also to deal properly with its damaging legacy when things go wrong, as they will.

Today, new nuclear power stations are being constructed in more than a dozen countries. China alone is working on almost half of the 65 reactors currently being built, and there is growing interest in the technology from developing countries. Supporters of the spread of civil nuclear power must acknowledge that some of these countries would be unable to cope alone if faced with a nuclear accident on the scale of Chernobyl.

Nations, particularly those pushing new nuclear build, must invest in bodies such as the International Atomic Energy Agency, to ensure that new and old reactors around the world are sufficiently safe, and that they are fully prepared for the worst. And politicians and the nuclear industry must revisit their relationship with a sceptical public. Being open and transparent about the uncertain costs of new build in countries such as the United Kingdom would be a start. If a public subsidy is required to get them built, then say so. If the industry wants people to believe its assurances that nuclear power is safe, then now is not the time for obfuscation and weasel words, on any aspect of the technology (see page 549).

Governments must also work to present a clear narrative about the health implications of accidents such as Chernobyl and Fukushima. For heroic plant workers exposed to extreme radiation doses — and for those still suffering from Chernobyl's legacy of thyroid cancer — the risks are all too clear. But it is harder to pin down more subtle health effects. There are hints that low-level exposure can raise the risk of cardiovascular disease, breast cancer and other conditions, consistent with the idea that there is no safe threshold for radiation exposure. To clarify the situation, the world needs studies of large numbers of people exposed to very low doses of radiation — and Chernobyl can provide those. Funding such research is vital for those affected by Chernobyl's radiation, but it should also answer some of the questions over the future of nuclear power.

People legitimately ask whether the low levels of radioactivity now drifting across Japan are safe. The current best answer is 'probably'. A better response would be to find out, before another 25 years pass.

[abhishek_sharma]

Radioactivity spreads in Japan

Fallout is localized, but could persist for years in some regions.

http://www.nature.com/news/2011/110329/ ... 1555a.html

In a week that has seen little good news about the stricken Fukushima Daiichi nuclear reactors, the latest data on radioisotope fallout from the plant is so far offering a glimmer of hope.

Monitoring efforts are showing that although the reactors have released significant amounts of radiation into the atmosphere, dangerous contamination is mostly localized in a narrow zone northwest of the plant. Emissions are also lower than immediately after the initial explosions, but radioisotope release continues and trends are unpredictable.

Working through the details is going to take time, and experts are struggling to assess the situation. "We don't have enough data yet, and what we have are still patchy," says Jim Smith, an environmental physicist at the University of Portsmouth, UK. In the meantime, the Japanese authorities are taking many of the right precautions, such as quickly implementing an evacuation zone, and banning farming and fishing in the areas worst affected, he says.

It is already clear that Japan's geography has been crucial to reducing the accident's impact. Initial estimates suggest that Fukushima's reactors have emitted one-tenth of all the radioactive material released during the Chernobyl disaster in 1986, and prevailing winds have swept most of the radioactivity over the Pacific Ocean. Austria's Central Institute for Meteorology and Geodynamics in Vienna estimated last week that although Fukushima's radioactive plume has now dispersed across the Northern Hemisphere, negligible levels of volatile radioisotopes such as iodine-131 and caesium-137 (the major components of the plume) have hit countries outside Japan. By contrast, radiation from land-locked Chernobyl spread across much of Europe (see page 562).

Fukushima's plume is still being fed by continued emissions from its damaged reactors, but when these are halted and the plume dissipates, the long-term impact on Japan will depend on which radioisotopes have been deposited on the ground, and in what quantities. Concentrations of caesium-137, which has a half-life of 30 years, are particularly important in determining which areas will be off-limits for settlement or farming, and for how many years.

On Sunday, the International Atomic Energy Agency (IAEA) reported that 16 of Japan's 47 prefectures showed daily deposition rates on the ground of less than 860 becquerels per square metre (Bq m−2) for iodine-131, and 100 Bq m−2 for caesium-137. The IAEA also reported that contamination has not increased in 28 of Japan's prefectures over the period 18–25 March. But higher contamination was recorded in Yamagata prefecture, immediately northwest of Fukushima prefecture: 7,500 Bq m−2 of iodine-131 and 1,200 Bq m−2 of caesium-137, which exceeds recommended contamination levels for growing green leafy vegetables. No data were available for Fukushima prefecture itself, where high contamination rates are expected.

Those data are consistent with the results of aerial monitoring of ground radiation carried out by the US Department of Energy. A survey of the region on 22 March showed no increase in deposition of radioactivity compared with a previous survey on 17–19 March, despite the wind blowing inland from the plant for some of that time, suggesting that there had not been a significant additional dump of radioisotopes.




The survey showed that the highest radioactivity doses on the ground (greater than 0.125 millisieverts per hour; mSv h−1) were restricted to a narrow band within 40 km of the plant, stretching to the northwest (see 'Fukushima's fallout'). No values anywhere exceeded 0.3 mSv h−1, a dose likely to cause adverse health effects in anyone continually exposed for a few months. Still, doses at some sites over the course of a year would top 1,000 mSv, enough to cause symptoms of radiation sickness, including nausea, hair loss and reduced white-blood-cell counts.

Much of the 20-km evacuation zone around the plant had far lower dose levels, below 0.012 mSv h−1. Nevertheless, that corresponds to a potential annual dose of more than 100 mSv, more than five times the annual limit permitted for UK nuclear-industry workers. The patchy distribution of fallout reflects the role of wind patterns and rainfall in washing out radio­isotopes to the ground. Overall, Smith says he was "relieved" by the data, as they suggest that contamination around Fukushima will be much lower than that seen around Chernobyl.

But some areas of high contamination seem to lie outside the exclusion zone. Soil samples taken on 20 March from a location 40 km northwest of the plant showed caesium-137 levels of 163,000 becquerels per kilogram (Bq kg−1) and iodine-131 levels of 1,170,000 Bq kg−1, according to Japan's science ministry. Acceptable contamination levels for areas used to grow crops are much lower, typically in the range of a few hundred Bq kg−1. "If there are significant areas of caesium-137 soil concentration of the order of 100,000 Bq kg−1, evacuation of these areas could be effectively permanent," says Smith.

Detailed maps of caesium-137 distribution would help to identify hotspots where people need to be evacuated urgently, he adds. An estimated 200,000 people have already been evacuated from Fukushima's 20-km zone, and on 25 March, the government encouraged people living in the 10-km radius beyond that to leave voluntarily.

The dispersal of much of the radioactivity over the ocean clearly helped to prevent a worse situation inland, but it is bringing its own problems. Data released last week by Japan's science ministry showed high surface sea­water concentrations of 24.9–76.8 becquerels per litre (Bq l−1) of iodine-131, and 11.2–24.1 Bq l−1 of caesium-137 some 30 km offshore, although these levels seem to be decreasing. By contrast, the IAEA reported this week that radioactivity levels near the plant's discharge pipes were increasing, with 74,000 Bq l−1 of iodine-131 and 12,000 Bq l−1 of caesium-134 and caesium-137 combined. Recommended maximum coastal discharges from nuclear power plants are typically lower than 4,000 Bq l−1.

As a result of the nuclear accident, Japan has banned all fishing within 20 km of the Fukushima plant. Seaweeds and other marine organisms can concentrate radioisotopes from the water, and it will be necessary to monitor their transport through the food chain, says Timothy Mousseau, a radioecologist at the University of South Carolina in Columbia. Smith adds: "There has obviously been significant contamination of the marine system, although I would expect that the enormous dilution of the ocean would significantly limit potential doses and impacts."

On 27 March, a new threat arose from highly radioactive water flooding the basements of Fukushima's reactors, in some areas delivering a potentially lethal dose of 1,000 mSv h−1. The water is seeping into piping trenches less than 70 metres from the sea shore, raising the spectre of serious contamination of the sea and groundwater in the area. Yukio Edano, Japan's chief cabinet secretary, has promised a massive effort to prevent that from happening.

As long as the reactors continue to release radioisotopes, the human and environmental toll from the Fukushima power plant can only grow. Once emissions are halted, atmospheric radiation levels will fall quickly, as will ground levels of short-lived isotopes. Iodine-131 is responsible for a large share of the total released radioactivity, for example, and has a half-life of just 8 days. But it may be many weeks, or months, before the power plant is tamed — and years before parts of northern Japan tainted by long-lived radioisotopes are habitable again.

[abhishek_sharma]

Chernobyl's legacy: Twenty-five years after the nuclear disaster, the clean-up grinds on and health studies are faltering. Are there lessons for Japan?

http://www.nature.com/news/2011/110328/ ... 1562a.html

The morning train from Slavutych is packed with commuters playing cards, browsing e-readers, or watching the monotonous flood plains pass by. It looks like any other routine journey to work. But rather than facing a crush through subway turnstiles at the end of the 40-minute trip, the workers are met by a row of full-body radiation monitors. It is the start of another day at the Chernobyl power plant, the site of the world's worst civilian nuclear disaster.

As the train trundles through the bleak Ukrainian countryside, another nuclear crisis is unfolding halfway around the world. Barely a week after the partial meltdown at the Fukushima Daiichi nuclear power station, it is no surprise that some of the chatter on the train turns to the incident there. "It looks bad," says one commuter. "But not as bad as Chernobyl," he adds, with a hint of grim pride.



When Chernobyl's reactor number 4 exploded in the early hours of 26 April 1986, the ensuing blaze spewed 6.7 tonnes of material from the core high into the atmosphere, spreading radioactive isotopes over more than 200,000 square kilometres of Europe (see 'The hottest zone'). Dozens of emergency workers died within months from radiation exposure and thousands of children in the region later developed thyroid cancer. The region around the plant became so contaminated that officials cordoned off a 30-kilometre exclusion zone that straddled Ukraine's border with Belarus. Today, a staff of about 3,500 enters the zone each day to monitor, clean and guard the site, where remediation work will continue for at least another 50 years (see 'Half-life of a disaster').

So far, the Fukushima accident is less severe. Radiation levels measured near the Japanese power plant have been less than those at Chernobyl after the blast there (see Table 1). And although radiation has spread from Fukushima, it does not match the amounts that rained down in the region around Chernobyl.

---------------------------------

Table 1

Dose (mSv) Source/implication
Up to 5,000 One minute’s exposure to Chernobyl core shortly after explosion
1,000 Causes temporary radiation sickness, including nausea and decreased white-blood-cell count
250 Upper annual limit allowed for Fukushima emergency workers
120 Average total dose received by liquidators at Chernobyl (1986–90)
30 Average total dose of external radiation received by evacuees from Chernobyl plant and surrounding area
20 Average annual limit for nuclear-industry workers
9 Total dose received by the 6 million residents in contaminated areas (>37 kBq m–2) in former USSR
9 One computed-tomography (CT) scan
9 Annual exposure of airline crew flying regularly between New York and Tokyo
3 One mammogram
2.4 Average annual background radiation globally
0.3 Total dose received by each resident of Europe for 20 years after Chernobyl

--------

Despite those differences, the quarter-century of work following the Chernobyl disaster will offer some important lessons for Japan as the nation begins to assess the health and environmental consequences of Fukushima. The problems that followed Chernobyl also provide a grim reminder about the value of accurate information. Officials need to tell people immediately how to avoid the initial, most dangerous, exposure; yet in the longer term, scientists and the government must battle against unnecessary concern over low-level doses of radiation, which often causes more harm than the radiation itself.

In some ways, the connection between the two accidents may yield the biggest benefits for Chernobyl. For a brief window of time, the world has again focused attention on the largely overlooked work there. The renewed interest may spur nations to chip in the cash needed to complete the clean-up of the site, and to carry out health studies that have languished for want of proper coordination and funding. "In recent years, Chernobyl has been neglected by funding agencies and, to an extent, the scientific community," says Jim Smith, a radioecologist at the University of Portsmouth, UK, who has studied the consequences of the accident for 20 years. "But there is still more to learn from Chernobyl about decommissioning and the effects of the radiation," says Smith, who is touring the site with a group of other scientists.

After clearing a security checkpoint, the visiting researchers board a bus that heads towards the heart of the ageing power plant. They pass abandoned buildings and bump along potholed roads running beneath archways made of piping; since the accident, pipes have been laid above ground to avoid disturbing contaminated soil.

The visitors stop to look at the most visible reminder of the accident, the concrete sarcophagus that entombs the shattered reactor building. Completed hastily in November 1986, the sarcophagus was built to contain the escaping radiation, but it is now crumbling and streaked with rust. Smith whips a dosimeter out of his rucksack and poses for a photograph in front of the sarcophagus. The reading is 5 µSv h−1: about 10 minutes of exposure at that level equals the same dose as an arm X-ray.

The plant's bright main office is a stark contrast to the sarcophagus. Stained-glass windows depict — in glorious socialist–realist style — the harnessing of atomic energy. But the plant has not produced power since 2000, when the last reactor was shut down. Valeriy Seyda, a deputy director of the Chernobyl Nuclear Power Plant, explains that the plant's top priority now is to construct a new confinement shelter for reactor 4 before the sarcophagus becomes too unstable. If it collapses before the new shell is in place, it could throw up a cloud of radioactive particles and expose the deadly remnants of the reactor.

Replacing the rusting tomb

The plan is to build an enormous steel arch adjacent to the reactor and slide it along a runway to cover the building. The arch will reach 105 metres high, with a span of 257 metres — the world's largest mobile structure, according to its designers. It is expected to be in place by 2015 and should last for 100 years. It will enable robotic cranes inside to dismantle the sarcophagus and parts of the reactor. Long-term plans call for finishing the clean-up work at Chernobyl by 2065.

Some of the concrete trenches for the project are in place. But the international Chernobyl Shelter Fund that supports the US$1.4-billion effort still lacks about half of that cash, and the completion date has slipped by almost ten years since the shelter plan was agreed in principle in 2001. One of the key goals of a forthcoming conference — Chernobyl, 25 Years On: Safety for the Future — to be held in Kiev on 20–22 April is to secure more cash commitments from international donors. Meanwhile, Chernobyl is developing long-term storage facilities for the debris that will be hacked out of reactor 4; and for more than 20,000 spent fuel canisters from the site's other reactors, a facility that will cost about €300 million (US$420 million).

Although all those reactors have been shuttered, the plant continues to generate large amounts of radioactive waste — partly because of persistent flooding in some of the waste-storage buildings and reactor 4's turbine hall. Every month, at least 300,000 litres of radioactive water must be pumped out of the structures and stored on site.

The main cause of this flooding is Chernobyl's brimming cooling pond, which artificially elevates groundwater levels in the area. Alexander Antropov, a Chernobyl veteran with ice-blue eyes and a cool manner to match, is in charge of a project to decommission the pond. The term 'cooling pond' usually refers to the containers where spent fuel rods are stored until their radiation dissipates enough that they can be put into long-term storage. But Chernobyl's pond is actually a vast reservoir covering 22 square kilometres into which water from the reactor cooling systems was discharged. The pond also contains long-lasting radioactive material such as caesium-137 and strontium-90, which rained down after the explosion. Besides causing flooding at the plant, the high water levels in the cooling pond raise the risk that a weak dyke along its east side will burst, which would send water coursing into the Pripyat River. Radioactivity in the escaping water would be quickly diluted by the river, so although it would not significantly raise exposure levels for people downstream, it could cause panic among the local population.

Antropov says that his team cannot simply lower the water levels in the pond because they don't know what effect microscopic radio­active sediment particles would have if exposed. In the meantime, the team maintains the status quo by pumping water from the Pripyat River into the pond at a cost of a few hundred thousand euros per year. But the long-term plan is to lower the water level by 7 metres to form a patchwork of 10–20 smaller ponds that would keep the most dangerous sediments in place. The project would cost €3 million to €4 million, says Antropov. He is already in discussions with the relevant regulators and is optimistic that the necessary feasibility studies and environmental impact assessments can be completed.

But the effort has been a long time coming. The decommissioning plan is more than a decade old, and was supported by a 2005 survey for the European Commission, led by Smith. Once again, money has been a key factor in the delay. The major parts of Chernobyl's decommissioning plan are paid for by international funds, but the cooling pond project is not. Nor is the research needed to satisfy the regulators. "Most of our own activities come from the Ukrainian budget, and we are not a rich country," says Seyda.


After leaving the cooling pond, the visitors stop at Pripyat, an abandoned town just 3 kilometres from the reactor complex. Some 44,000 residents were evacuated the day after the accident, and many of their belongings still litter the decaying buildings. Antropov once lived here — his daughter was a few months old at the time of the accident — and as deputy chief of the town's Communist party office, he was responsible for evacuating part of the town. Because he worked as a senior engineer at the nuclear plant, he knew that the disaster would have repercussions for decades to come. "I understood that I would never return to live in Pripyat," he says, in an uncharacteristically soft voice. "I still feel some sense of loss."

The evacuees from Pripyat also live with lingering fear about the radiation they were exposed to before fleeing their homes. Along with millions of others from the surrounding regions, they often attribute any sign of ill health to the accident. But pinning down Chernobyl's true public-health impact has proved remarkably difficult.

There is little disagreement about the terrible fate of the workers who brought Chernobyl's stricken reactor under control. Of 134 emergency workers diagnosed with acute radiation sickness, 28 died from their exposure within four months. Another 19 have died since from various causes, and many of the surviving workers now have cataracts and skin injuries.

More than 5,000 cases of thyroid cancer have so far been seen in people who were children at the time of the accident and lived in contaminated areas of the former Soviet Union — a more than ten-fold increase from normal levels (adults were mostly unaffected by the disease). Most of these cases were caused by drinking milk contaminated with radioiodine. Fewer than 20 of these people have died, but the sheer number of cancers, and their rapid onset within 5 years of the accident, surprised many epidemiologists.

This triggered a plethora of thyroid studies, most notably a long-term cohort study of 25,000 people in Ukraine and Belarus who were children in 1986 that is being coordinated by the US National Institutes of Health's National Cancer Institute (NCI) in Bethesda, Maryland. The latest results from the Ukrainian section of this cohort1 confirm previous findings that the incidence of thyroid cancer is proportional to the size of the dose, with a particularly high risk seen in younger people and in those who were iodine-deficient due to poor diet. The research is having a direct impact in Japan, where those at risk of exposure are being given potassium iodide tablets to prevent the uptake of radio­iodine in their thyroid.

The NCI oversees a second cohort made up of liquidators, a group of more than half a million people sent into the exclusion zone to help clean up and monitor the area after the initial emergency phase of the accident. Liquidators have a slightly raised risk of developing cataracts, and possibly a small increased risk of leukaemia2.

Long-term effects

But what was the impact on the wider population? Various studies have tried to estimate how many deaths Chernobyl will eventually cause across the whole of Europe, but their answers range from a few thousand to hundreds of thousands3. Cancer causes about a quarter of all deaths in Europe, so teasing out Chernobyl's far-reaching influence would probably be impossible, say epidemiologists. Moreover, focusing on such intangible numbers can distract from the much broader social impact of the accident. In Ukraine and Belarus, hit hard by the break-up of the Soviet Union in 1991, lingering fears about radiation are thought to have contributed to a sense of hopelessness that is linked to high rates of alcoholism and smoking — factors that have a much bigger health impact.

"There's tremendous uncertainty for these people," says Elisabeth Cardis, a radiation epidemiologist at the Centre for Research in Environmental Epidemiology in Barcelona, Spain. "Some think they are doomed because of their radiation exposure." Further research could provide convincing evidence that Chernobyl's radiation did not significantly harm the wider population, but "we won't know unless we look", says Dillwyn Williams, a cancer researcher at the Strangeways Research Laboratory in Cambridge, UK.

A handful of Chernobyl studies have found small increases in rates of breast cancer and cardiovascular disease, but they did not properly account for confounding factors, such as nutrition, alcohol consumption and smoking habits. And although some researchers have claimed to see an increase in genetic mutations in the children of parents irradiated after Chernobyl4, there has been no similar evidence of hereditary effects even in the children of Japanese atomic bomb survivors, who on average received much larger radiation doses.

This means that there is still a substantial gap in the overall understanding of Chernobyl's health effects, says Williams. The problem is exacerbated by the piecemeal nature of previous studies. "There has been a failure of European-level coordination on this," he says.

Williams hopes that there is now a chance to establish a Chernobyl Health Effects Research Foundation, which would mirror the highly effective Radiation Effects Research Foundation that monitors the long-term health impacts of the atomic bombs in Japan. Together, the efforts could reveal the differences between the single short-term dose of external radiation delivered by the atomic bombs, and the low-level long-term exposure seen after Chernobyl. Long-term doses were once thought to carry much less risk than the immediate exposure, but evidence is accumulating that the risks may be much the same5. If confirmed, it would mean that people routinely exposed to low-level radiation have a greater chance of health problems than previously thought.

The European Commission has funded Williams, Cardis and a core group of other scientists to develop a research plan, dubbed the Agenda for Research on Chernobyl Health (ARCH), that maps out how the existing cohorts could be used to study a wider range of diseases, such as breast cancer and cardiovascular disease, and to address the questions about the long-term effects of low doses. The liquidator cohort, for example, is six times larger than that of atomic bomb survivors, with a much wider range of exposure doses. It could show how risk varies over that large range of doses and uncover rarer effects at lower doses. It could also help to reassess the threshold dose to prevent nuclear workers from developing problems such as cataracts.

ARCH also suggests testing the feasibility of setting up new cohorts including liquidators' offspring and highly exposed evacuees, along with a tissue bank. The bank may reveal whether people's genetic make-up influences their susceptibility to radiation — key information for determining how individuals are likely to respond to the radiation received during medical procedures such as X-ray scans and radiation treatment.

There are several hurdles, however, to getting ARCH off the ground. The project needs support from the NCI, which stopped funding active clinical monitoring of the thyroid cohort in 2008 because of budgetary constraints. And ARCH's proposals would also require better access to medical records in Ukraine and more information about participants' lifestyle factors — both potentially tall orders.

The ARCH plan will be presented at the 25th anniversary conference in April, and Cardis hopes that a positive reception will prompt the European Commission to boost its support. It is likely to be difficult to secure a long-term commitment for the studies, which will cost about €3 million to set up, but that cost is minor compared with the billions that will be spent on remediation at Chernobyl, says Williams.

Beyond obtaining the necessary funds, researchers will also require cooperation from participants to expand the cohort studies. That could be difficult. Gennady Laptev, now a hydrologist based at the Ukrainian Hydrometeorological Institute in Kiev, was a liquidator for three years, and says that he stopped attending his medical check-ups about ten years ago because they were too time-consuming. "They never found any major health problems," he says.

Laptev's work involved flying by helicopter from Kiev to Chernobyl twice a week to take radiation readings and collect soil and water samples for analysis. "Nobody forced me to do the work — I did it because it was interesting, and I really enjoyed it," he says. But after three years, he became worried about the risk of working near the plant, so he took a job researching how radioisotopes dispersed in the local water system (see 'Life as a liquidator').

Concerns about radiation exposure continue to plague residents in the region, and the planned studies could provide the answers they so desperately need about Chernobyl's real health legacy. "I have a house in a village near Slavutych, on contaminated territory," says Antropov during the site visit. "Two of my neighbours died of cancer, and this was probably the result of their radiation doses."

Lessons for Japan

It's too early to say how the Chernobyl health studies will help those affected by the Fukushima accident. But Chernobyl has already given the world a lasting lesson on the importance of clear communication during a nuclear disaster, and in the years afterwards.

There was no systematic distribution of prophylactic potassium iodide to the people around Chernobyl, and Pripyat's children were allowed to play outside during the day after the accident, while the reactor continued to burn. "The failure to rapidly communicate radiation risks at Chernobyl led to people receiving higher radiation exposures than was necessary," says Smith.

The Japanese government has been lambasted for not keeping citizens well informed about the accident there. But it was swifter to act than Soviet officials were, ordering the evacuation of people who live near the plant within hours of recognizing the growing nuclear emergency, and expanding that evacuation zone to a radius of 20 kilometres the following day. As well as distributing potassium iodide, the Japanese government banned the sale of food and milk produced in the provinces around the stricken plant. "The Japanese have done exactly the right thing," says Andrew Sherry, director of the Dalton Nuclear Institute at the University of Manchester, UK.

Ultimately, says Smith, Chernobyl's most important lesson for Fukushima is that a nuclear accident haunts a region long after the reactors have cooled. If areas of Japan are significantly contaminated with radioactive caesium-137, which loses half its radioactivity in 30 years, the government may have to maintain an exclusion zone for decades. Decommissioning the Fukushima reactors may also take decades, depending on the extent of damage to their cores. And the uncertainty surrounding the health risks may exact a psychological toll that could surpass the physical harm from the radiation, adds Smith.

Many of the workers at Chernobyl understand those lessons all too well as they shuffle onto the train to Slavutych at the end of their day. The workers will return to tend to the plant tomorrow and the next day — and for many years to come.

Mark Peplow is Nature's news editor.

References
Brenner, A. V. et al. Environ. Health Perspect. doi:10.1289/ehp.1002674 (2011).
Cardis, E. & Hatch, M. Clin. Oncol. doi:10.1016/j.clon.2011.01.510 (2011).
Peplow, M. Nature 440, 982-983 (2006). | Article | PubMed | ISI | ChemPort |
Dubrova, Y. E. et al. Nature 380, 683-686 (1996). | Article | PubMed | ISI | ChemPort |
Health Risks from Exposure to Low Levels of Ionizing Radiation: BEIR VII Phase 2 (NRC, 2006); available at http://go.nature.com/r7jeca.

[Sanku]

WRT to the Fukushima workers..

They are the ones putting their health and safety on the line. They know what they deal with. They can characterize it how ever they want. Firefighters who go into blazes say the same all the time, that 'they expect to die.' They do it anyway. Let us honor their courage rather than casting aspersions on the risk they face.

I am sure they expect that the current set of events will harm them substantially leading to a shortened life span, and probably painful diseases. They are there locally, they know what is happening exactly, they don't have the luxury of taking a detached "will I wont I" about their lives, "oh the statistics show that I only have a 68% risk in high band, 43% in middle band...." It is quite likely that they will be straight forward about it.

The real world implications of the disaster keep coming in.

http://www.news.com.au/breaking-news/ja ... 6031719344

Japan finds radiation in beef

The health ministry said 510 becquerels of radioactive cesium had been detected in beef from Tenei in Fukushima prefecture, about 70km from the plant - exceeding the 500-becquerel limit, Kyodo News said.

On Saturday, officials said that lettuce contaminated with radiation above the legal limit had been found at a wholesale market in central Japan, shipped from a farm north of Tokyo.

The dangerous part is, the more dangerous form of radioactive material w.r.t. health, Cesium is being found in huge quantities

http://www.newscientist.com/article/dn2 ... nobyl.html

Caesium fallout from Fukushima rivals Chernobyl

An analysis of MEXT's data by New Scientist shows just how elevated the levels are. After the 1986 Chernobyl accident, the most highly contaminated areas were defined as those with over 1490 kilobecquerels (kBq) of caesium per square metre. Produce from soil with 550 kBq/m2 was destroyed.

People living within 30 kilometres of the plant have evacuated or been advised to stay indoors. Since 18 March, MEXT has repeatedly found caesium levels above 550 kBq/m2 in an area some 45 kilometres wide lying 30 to 50 kilometres north-west of the plant. The highest was 6400 kBq/m2, about 35 kilometres away, while caesium reached 1816 kBq/m2 in Nihonmatsu City and 1752 kBq/m2 in the town of Kawamata, where iodine-131 levels of up to 12,560 kBq/m2 have also been measured. "Some of the numbers are really high," says Gerhard Proehl, head of assessment and management of environmental releases of radiation at the International Atomic Energy Agency.

[abhishek_sharma]

Disaster, panic, and plans

http://hoffman.foreignpolicy.com/posts/ ... _and_plans

While the aftermath of the Japan nuclear crisis continues to unfold, there are two good stories out today casting light on planning for a possible disaster and how the workers coped when it happened. ...

[Singha]

bbc:

The evacuation of residents near Japan's quake-hit Fukushima nuclear plant will be long-term, officials say.

Many of the tens of thousands of people evacuated from the area around the plant are living in temporary shelters.

The announcement came as high levels of radiation were detected for the first time in groundwater near one of the facility's six reactors.

Meanwhile, a massive search has begun to find the remains of those missing since the devastating tsunami hit.

Three weeks after the 9.0-magnitude earthquake and subsequent tsunami, the true number of those who died is still not known.

More than 11,500 people are confirmed dead but nearly 16,500 remain unaccounted for.

More than 100 Japanese and US military planes and 65 ships are scouring the country's north-eastern coast to locate any remaining bodies that could be recovered.

Employing some 24,000 military personnel, the intensive air and sea operation will focus on shores that were largely submerged or remain under water, as well as the mouths of major rivers.

Many coastal areas remain inaccessible to rescuers trying enter by road or foot, blocked by the mangled remains of houses, ships, cars and trains.

[Lalmohan]

i saw a tv programme recently that showed how the tsunami had surged up rivers, in some cases driving flow high into the mountains and creating lakes in mountain villages. the locals were afraid that as the waters retreated they would find hundreds of dead bodies

very grim

[Lalmohan]

A long update in the doyen of the left leaning green papers - al guardian: Nuclear radiation seeps into Japanese groundwater

some highlights

The other concern is that contaminated water could seep into underground waterways and eventually into rivers used for drinking water. Tomohiro Mogamiya, an official with the Ministry of Health, Labour and Welfare's water supply division, said that was "extremely unlikely" since groundwater would flow toward the ocean, and the plant is right on the coast.

In the latest report of food becoming tainted, the government said on Friday that a cow slaughtered for beef had slightly elevated levels of cesium, another radioactive particle. Officials stressed that the meat was not put on the market.

Despite the leaks, Tepco hasn't had enough dosimeters to provide one for each employee since many were destroyed in the earthquake. Under normal circumstances, the gauges, which measure radiation, would be worn at all times.

Officials said on Friday that more meters had arrived and there were now enough for everyone.

"We must ensure safety and health of the workers, but we also face a pressing need to get the work done as quickly as possible," said nuclear safety agency spokesman Hidehiko Nishiyama. Until now, sharing meters "has been an unavoidable choice".

Tepco has repeatedly relaxed safety standards during the crisis in order to prevent frequent violations. That is not uncommon during emergencies.

The company has acknowledged it was initially slow to ask for help in dealing with the crisis, but experts from around the world are now flooding in. The French nuclear giant Areva, which supplied fuel to the plant, is helping figure out how to dispose of contaminated water, and American nuclear experts are joining Japanese counterparts on a panel to address the disaster.

Japan has ordered two giant pumps, typically used for spraying concrete, from the US. They are being retrofitted to spray water first, according to Kelly Blickle, a spokeswoman at Putzmeister America in Wisconsin. At least one similar pump is already in operation at the plant

[Lalmohan]

and the cynical financial industry neo-fascists chip in

Sushi Safe From Japan Radiation as Ocean Makes Risk Negligible

“Eating fish is not something to worry about,” said Gale, a visiting hematology professor at Imperial College London who was in Japan this week to speak to doctors responding to radiation threats. “No one could afford to consume enough sushi to get radiation damage.”

Since last week, the Fisheries Research Agency has tested samples from five types of fish caught off the coast of Choshi city in Chiba prefecture, the fishing area south of the Fukushima nuclear plant. The institute has been monitoring radioactivity in Japanese marine life for the past five decades, after nuclear arms testing by the U.S. and the former Soviet Union raised concerns about contamination.

Cesium Levels

The institute detected 3 becquerel per kilogram of cesium-137 in anchovy, but nothing in samples from alfonsino, mackerel, spear squid and olive flounder. The level was far below the standard set by Japan’s health ministry of 500 becquerel per kilogram for fish.

Radioactive elements in the ocean are significantly less harmful than if they are airborne or permeate the soil, Gale said.

“From a radiation safety point of view, if it’s got to go somewhere, that’s the best place,” he said. “Radiation is least dangerous to humans when diluted, so the sea is the perfect place.”

While dilution lessens the risks the further marine life is from the source of contamination, Qian said people should avoid any seafood from the immediate vicinity of the Fukushima plant.

“Be alert, but don’t panic,” he said.

[Sanku]

Nice graphic and image providing a snapshot of radiation leaks

http://www.bbc.co.uk/news/world-asia-pacific-12911190

[Sanku]

Ramana; Saar did you get through to this gent?

Anupam Chander is a professor of law at UC Davis.

http://www.latimes.com/news/opinion/com ... 8225.story

Who's to blame for Fukushima?

In a legal sense it is too early to know, but General Electric, the designer of the stricken plant, might not entirely escape liability for the nuclear disaster.

. The explanation: Japanese law reportedly limits liability to the operator, not the designer, of a nuclear power plant.
...
A year ago, we heard similar arguments about the limited exposure of BP in the wake of the oil spill in the Gulf of Mexico.
...
The Justice Department called Transocean's effort to limit its liability "simply unconscionable."


Modern disasters are, in an important sense, man-made. Because of this fact, the need to assign legal liability will arise.

Woo!! Supplier long term liability, public vs private spending. Man made disasters.

This looks like it has rolled of BRFites keyboard, yet set in US sense in US mileu with their laws etc.

------------------

To all:
PS> I told you so.

[Amber G.]

Forget about I-131, Cs etc...
Check this out today..
http://dhmo.org/facts.html
Excerpts:

Should I be concerned about Dihydrogen Monoxide?

Yes, you should be concerned about DHMO! Although the U.S. Government and the Centers for Disease Control (CDC) do not classify Dihydrogen Monoxide as a toxic or carcinogenic substance (as it does with better known chemicals such as hydrochloric acid and benzene), DHMO is a constituent of many known toxic substances, diseases and disease-causing agents, environmental hazards and can even be lethal to humans in quantities as small as a thimbleful.
....
What are some of the dangers associated with DHMO?

Each year, Dihydrogen Monoxide is a known causative component in many thousands of deaths and is a major contributor to millions upon millions of dollars in damage to property and the environment. Some of the known perils of Dihydrogen Monoxide are:

Death due to accidental inhalation of DHMO, even in small quantities.
Prolonged exposure to solid DHMO causes severe tissue damage.
Excessive ingestion produces a number of unpleasant though not typically life-threatening side-effects.
DHMO is a major component of acid rain.
Gaseous DHMO can cause severe burns.
Contributes to soil erosion.
Leads to corrosion and oxidation of many metals.
Contamination of electrical systems often causes short-circuits.
Exposure decreases effectiveness of automobile brakes.
Found in biopsies of pre-cancerous tumors and lesions.
Given to vicious dogs involved in recent deadly attacks.
Often associated with killer cyclones in the U.S. Midwest and elsewhere, and in hurricanes including deadly storms in Florida, New Orleans and other areas of the southeastern U.S.
Thermal variations in DHMO are a suspected contributor to the El Nino weather effect.
<snip>

[Lalmohan]

dude, i have known people who are severely allergic to DHMO - really bad cases
i am trying to devleop a more open and embracing attitude to it, i can't avoid it, i must learn to enjoy it (adapted from 'how i learned to stop worrying and live with the bomb')

[Sanku]

Was DMHO a issue in the current set of Japan disasters? If not perhaps some other thread would be better to discuss it for those who are interested? If yes, perhaps more details as to the connections?

[Virupaksha]

Was DMHO a issue in the current set of Japan disasters? If not perhaps some other thread would be better to discuss it for those who are interested? If yes, perhaps more details as to the connections?

DHMO was what caused all the destruction.

[GuruPrabhu]

The irony is that they are trying to solve the crisis caused by DHMO by applying more DHMO to the problem.

[Theo_Fidel]

Not only that the DHMO is now contaminated and people have been told not to drink it. Swimming in the DHMO off the plant may not be advised. DHMO is slippery when wet and impossible to control its spread. Contaminated DHMO in the reactor basement even sent 3 workers to the hospital. I say we try to find alternatives to DHMO.

[Lalmohan]

i am shocked that the models failed to see how the EQ would lead to DHMO spreading far inland

[chaanakya]

self deleted.

I feel sorry for the .....

Sankuji , I am really sorry for having fallen for IED.

[Lalmohan]

you mean Ureobovinic Acid?