Energy

Fukushima Nuclear Incident Highlights Disaster Management

By Ryan McGreal
Published March 14, 2011

I'm not a fan of nuclear power, for a variety of reasons; but the disaster management at the Fukushima I Nuclear Power Plant in Japan has been a breathtaking accomplishment of engineering-for-safety before a disaster and competent management during a disaster in which nearly everything that could go wrong went wrong.

Perhaps surprisingly, watching the horrible events play out at Fukushima I has actually somewhat increased my confidence in the capacity of sound engineering and competent crisis management to mitigate the inherent risks.

The 8.9 magnitude earthquake that struck Japan on Friday, March 11 was several times more powerful than the plant was designed to withstand. Nevertheless, the plant withstood it and the reactors survived intact - even though the facility is 40 years old.

Crisis After Crisis

The first crisis came with the earthquake. As planned, the reactors immediately went into shutdown, meaning that control rods were fully inserted into the reactor cores to absorb neutrons and stop the nuclear chain reaction.

(Note: in pressurized water reactors like the CANDU design, the control rods are suspended electromagnetically above the reactor and automatically drop down when power is disrupted. Fukushima I is a boiling water reactor, in which the control rods are held below the reactor using high pressure hydraulic accumulators and are raised automatically when power is disrupted.)

However, fuel rods continue to produce residual heat for several days after the fission chain reaction has stopped and require ongoing cooling - essentially, pumps circulating cold water to absorb and remove decay heat.

This brings us to the second crisis: the power supply to the cooling systems was disrupted when the earthquake damaged the electricity grid. As planned, the backup diesel generators kicked in to power the pumps.

An hour later, the third crisis hit: the tsunami roared down the coast from Sendai and washed out the diesel generators. As planned, the secondary backup batteries kicked in. As the batteries discharged, mobile generators were brought to bear to continue providing power.

However, these methods provided insufficient power to properly cool the reactors. The officials realized the potential existed for a partial or complete nuclear meltdown, in which the fuel rods get so hot that they literally melt the reactor and release dangerous levels of radiation into the environment. They evacuated some 170,000-200,000 people from the surrounding area as a precaution.

Explosions

The operators had to step in and carefully manage the heat and pressure inside the reactors. One method of doing this was to release some of the steam inside the reactors to reduce the pressure to safer levels. This resulted in three explosions - on March 12, 13 and 15 respectively - that partially destroyed the buildings housing the Unit 1, 3 and 2 reactors.

Before and after images of the explosion at Fukushima I Unit 1 reactor (Image Credit: Wikipedia)
Before and after images of the explosion at Fukushima I Unit 1 reactor (Image Credit: Wikipedia)

The explosions appear to have been caused by hydrogen formed inside the reactors due to high pressure and falling water levels. The hydrogen reacted explosively after the engineers vented the reactors and released it. They also released some radiation, resulting in elevated levels outside the reactors and the evacuation of 800 staff.

The first two explosions did not compromise the reactors themselves. The third explosion, caused when the explosion at Unit 3 damaged the pumping system for Unit 2 and left the fuel rods dangerously exposed for several hours, may have damaged the Unit 2 reactor.

Reports suggest that the explosion occurred at the bottom of the unit in the pressure system and may have breached the reactor itself, resulting in a radiation leak.

A fourth explosion just took place in Unit 4, which was not in operation when the earthquake struck but is being used to house spent fuel rods. A fire in the reactor seems to have triggered the release of hydrogen.

Operators have been pumping sea water and boric acid into all the reactors to maintain cooling and prevent meltdowns, though periodic aftershocks have at times disrupted their efforts.

So far, 15 plant personnel have been injured in the explosions and up to 190 people have been exposed to elevated radiation levels. No major radiation leaks have been reported to date - the radiation released through venting has been mild and short-lived.

The situation is now probably under control, though the corrosiveness and impurity of the sea water means the reactors will likely never operate again.

Prime Minister Naoto Kan just announced that the evacuation has been extended to a 20 km radius around the plant and that people between 20 and 30 km from the plant should stay indoors. He added that there is a "very high risk of further radioactive material coming out" of the reactor.

Multiple Simultaneous Catastrophic Failures

Essentially, a multiple-event disaster that far exceeded the design specifications of a 40 year old plant has at worst possibly produced a partial meltdown in which the radiation has been almost entirely contained.

Here we have an example of an incredibly fault-tolerant system that survived multiple simultaneous catastrophic failures with no loss of life (so far) and ongoing containment of radioactive material.

Assuming the situation holds, this will have been achieved through a dazzling combination of engineering for safety, multiple redundant backups, and careful crisis management during a volatile and unpredictable series of disasters.

Of course there are a number of possible interpretations and conclusions we can draw from these events, and I'm sympathetic to all of them.

For many people, the mere possibility of a catastrophic meltdown renders nuclear power an unacceptable risk. The fact that the risk of a meltdown must be actively managed and mitigated for several days after automatic shutdown means the system is not inherently safe no matter how you spin things.

Others will point out that, next to the appalling devastation of the earthquake and tsunami, which may have killed 10,000 people, the situation at Fukushima is almost benign by comparison.

Policy Implications

I don't pretend to know enough about Japanese culture and politics to have any idea what the long-term political consequences will be from this incident.

Will the Japanese people turn decisively away from nuclear power? If so, will mounting public opposition be enough to pressure the government into decommissioning the 53 functioning nuclear plants that currently provide a quarter of Japan's electricity, and/or cancelling plans in the works to build additional reactors?

As fossil fuels availability goes into decline, these issues are going to come up again and again. The questions remain: how much risk is acceptable in exchange for enough electricity to power a modern economy, particularly in an earthquake-prone region; and what technology, policy and oversight options are available to mitigate that risk?

Worldwide, after a long decline in popularity starting in the 1980s, policy interest in nuclear power has increased in recent years in response to high oil prices. Supporters have touted modern nuclear reactors as a panacea that will allow us to transition away from fossil fuels. Will this disaster reverse the global trend toward accepting nuclear power?

Nuclear Power in Canada

Canada has 18 active CANDU reactors operating at five sites, most of them in Ontario, that produce 15 percent of Canada's electricity (and 50% of Ontario's electricity). The Province of Ontario is planning to build another reactor, either at Bruce Nuclear Station or Darlington Nuclear Station.

I grew up in sight of the Pickering Nuclear Station. We used to wade up Duffin's Creek and fish in Frenchman's Bay. In winter, we used to toboggan on the hills at Brock Rd. and Montgomery Park Rd. in front of the reactors.

I must admit to a visceral aversion to nuclear power, doubtless spurred in part by a childhood in the paranoid 1980s at the height of hostilities between the USA and the USSR. Still, I try to make policy decisions based on a sound understanding of the facts rather than blind fear.

Again, I'm surprised to find myself somewhat heartened by how well the Fukushima I plant has survived the massive traumas to which it has been subjected. Canada's nuclear facilities, in contrast, are situated in geology that is orders of magnitude safer.

On the other hand, I'm left wondering whether we can trust our government officials to maintain the same obsessive commitment to safety engineering as their Japanese counterparts.

Ryan McGreal, the editor of Raise the Hammer, lives in Hamilton with his family and works as a programmer, writer and consultant. Ryan volunteers with Hamilton Light Rail, a citizen group dedicated to bringing light rail transit to Hamilton. Ryan writes a city affairs column in Hamilton Magazine, and several of his articles have been published in the Hamilton Spectator. His articles have also been published in The Walrus and HuffPost. He maintains a personal website, has been known to share passing thoughts on Twitter and Facebook, and posts the occasional cat photo on Instagram.

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By aprilkay86 (anonymous) | Posted March 14, 2011 at 23:42:21

I enjoyed your summary of events. I truly hope this "nuclear crisis" will end well. If not I wish we can turn in a new direction away from our current metropolitan lifestyles.

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By Radman (anonymous) | Posted March 15, 2011 at 00:09:55

Don't count your two-headed chickens yet, this disaster is still unfolding and could still go south in a big way. Imagine a major aftershock hits right near the plant or another explosion damages the pumping equipment so they can't keep cooling a reactor or another fire in an offline reactor leaks more rads. Already the radiation outside has spiked to a 1000 times higher than it was just a day ago, that could still get ALOT worse if more events occur. And the worse the radiation gets the less chance there is to do something about it because you need to evacuate the people that are supposed to deal with it. This SNAFU could definitely go FUBAR at any time, don't believe the Japanese government when they say things are under control.

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By Zot (anonymous) | Posted March 15, 2011 at 00:53:17

"The situation is now probably under control"
Wow, Ryan, what on earth are you smoking? Whatever it is change suppliers and get the clean stuff.

- No stable cooling situation in place for any of the troubled reactors
- Apparently no cooling in place at all for the spent fuel stockpile
- Loss of secondary containment due to:
- Hydrogen explosions from ongoing venting
- Apparent partial breach of primary containment in at least 1 of the reactors
- Being reported now: spent fuel on fire in #4 reactor building, significant releases of radiation in the combustion products.
- On site staff for firefighting and control efforts now cut from 800+ to 50 or so due to radiation exposure risk

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By Ezaki Glico (anonymous) | Posted March 15, 2011 at 01:28:41 in reply to Comment 60956

http://www.nytimes.com/2011/03/15/world/asia/15nuclear.html?_r=1&hp

"...the crisis at the Fukushima Daiichi Nuclear Power Station [has now become] the worst nuclear accident since the Chernobyl reactor disaster a quarter century ago...
After an emergency cabinet meeting, the Japanese government told people living with 30 kilometers, about 18 miles, of the Daiichi plant to stay indoors, keep their windows closed and stop using air conditioning."

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By Huffy (anonymous) | Posted March 15, 2011 at 01:57:54

When I look at the same facts, I draw the exact opposite conclusion. I see a bunch of related design weaknesses and flaws. They all boil down to overly optimistic design that didn't provide enough protection in a severe earthquake. I'm guessing the power company balked at the higher costs of multiple layers of protecting against really bad quakes.

What I see:
Failure to provide for sufficient backup electrical power to provide emergency cooling - specifically failure to provide sufficient fuel for emergency electric generators for cooling in a crisis.
Failure to provide a sufficient reservoir of clean water for emergency cooling.
Failure to provide for a safe vent path for hydrogen generated in this kind of cooling failure emergency.

My natural inclination is and has always been to favor nuclear power. But as I watch this unfold, I'm having real doubts. If the Japanese, great engineers, who know about earthquakes and who know the perils of nuclear exposure, won't put enough emphasis on safety to preclude these kinds of incidents, I doubt I'll trust anyone else to do so. I've never before thought nuclear power was intrinsically too dangerous (or that people wouldn't / couldn't be trusted to build things with multiple and expensive layers of protective systems, but now I'm leaning towards saying no to any nukes, anywhere...

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By mrgrande (registered) | Posted March 15, 2011 at 08:45:27 in reply to Comment 60959

Failure to provide for sufficient backup electrical power to provide emergency cooling - specifically failure to provide sufficient fuel for emergency electric generators for cooling in a crisis.

I was under the impression that they had this (as well as the water resovoir), however they were destroyed in the tsunami.

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By fail mode (anonymous) | Posted March 15, 2011 at 08:55:56 in reply to Comment 60967

I guess it depends on what you mean by "failure".

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By Undustrial (registered) - website | Posted March 15, 2011 at 02:58:38

I must say, as someone who's been following this situation since the wee hours of Saturday morning, I really don't see any of it as "under control".

Ever since the crisis broke there's been a mad scramble to downplay it. Every few hours, though, another reactor's lost cooling, exploded, caught fire, venting gas, or "partially" melting down. The attempts to pump in seawater have been fraught with problems (and will probably mean the end of the life for these reactors), and there've been reports of pulling workers off the site due to rising radiation. Reports of radiation large distances away... These are all very bad signs. If only one of these reactors had seen it's respective calamities, this may well still have been the second or third worst nuclear disaster in history.

One reactor would have been unfortunate - two a wake up call. But four at one plant and other difficulties elsewhere? This is a nightmare. And Superman shows up right this instant and fixes everything, it will still have been a nightmare. If this doesn't prompt some serious soul-searching about our energy systems, I really don't know what will.

As for how much radiation has been released, or what effect it will have in the long term, I'm pretty sceptical that anyone can discount it at this point. It's taken decades and we still don't totally understand Chernobyl. Expect to hear about new studies on what "really happened" here to be popping up for years to come.

Click the "Website" link for more coverage.

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By ClarkW (anonymous) | Posted March 15, 2011 at 07:51:52 in reply to Comment 60961

"Every few hours, though, another reactor's lost cooling, exploded, caught fire, venting gas, or "partially" melting down."

First of all no reactors have "exploded" yet, only some of the buildings AROUND the reactors have had their roofs blown off after workers vented the steam out of the reactors and the superhot steam separated into hydrogen and oxygen and then reacted together. Secondly, venting gas isn't a problem, it's one of the tools they have to keep the reactor from overheating. The steam is radioactive for a couple of seconds--that's where the spikes in rad levels are coming from--but it's the kind of radioactivity that becomes stable again almost immediately. The steam is a bit dirtier thanks to the seawater they're using because the salt and crap is a bit more reactive than pure distilled water but it's still extremely short lived. Third of all none of the reactors has melted down, not fully or partially or anything elsely.

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By Ezaki Glico (anonymous) | Posted March 15, 2011 at 07:45:59

The manmade artifacts (GE-designed?), to my mind, are not as notable as the human element of this story. For all the touted systemic fail-safes, it's the "engineering solution" of the 50 selfless souls who opted to stay on that may be remembered the most. Once a more fulsome body of facts emerge independent of the filtration of the Japanese government and regulatory bodies ("crisis management" is another way of describing for spin), we may be better able to assess how well or poorly the system performed and how much came down to inspired improvisation. I would hate to think that nuclear safety simply relies upon human sacrifice of one order or another.

The "acceptable risk" engineering solution of building safeguards against only mid-magnitude quakes is another matter entirely. Was it that scientists in 1967 knew how to build a cluster of reactors but felt that despite straddling Pacific-Philippine-Eurasian triple plate junction, incorporating defences against anything stronger than an 8 was an wasteful long-shot?

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By Ezaki Glico (anonymous) | Posted March 15, 2011 at 07:54:11

As to why the Japanese government might want to control this story, it's possibly not simply a matter of domestic peace of mind but may also be attributable to the country's problematic financial performance in recent times, which has apparently been just outside of the company of PIIGS:

http://megoyanagi.blogspot.com/2010/11/japan-stagnates-in-stock-market.html

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By Ezaki Glico (anonymous) | Posted March 16, 2011 at 20:58:07 in reply to Comment 60965

Mar 14: Bank of Japan injects 15 trillion yen into economy
http://www.businessweek.com/news/2011-03-14/boj-pours-record-183-billion-into-japan-s-financial-system.html

Mar 15: BoJ tops up economic transfusion by 5 Trillion Yen
http://www.koreaherald.com/world/Detail.jsp?newsMLId=20110315000661

A marvel of efficiency! The equivalent of $244 billion in the space of two days, compared to the weeks and months it took for the US to inject $700 billion to prop up its economy. (And Japan with a population about 2/5 the size of the US.)

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By Ezaki Glico (anonymous) | Posted March 16, 2011 at 21:16:17 in reply to Comment 61018

Flashback! Michael Lewis (The Big Short, Panic, The New New Thing, Liar's Poker) '89 article on "How a Tokyo Earthquake Could Devastate Wall Street and the World Economy"

http://www.scribd.com/doc/50850211/ML-Tokyo

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By JasonAAllen (registered) - website | Posted March 15, 2011 at 08:10:19

An interesting assessment from someone with a good backgroun in Nuclear Safety - http://theautomaticearth.blogspot.com/20...

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By Ezaki Glico (anonymous) | Posted March 15, 2011 at 09:11:05 in reply to Comment 60966

Regarding theautomaticearth's reactor map: Good on TEPCO for being bold enough to put six of its seven eggs in the basket of Japan's eastern seaboard – most of the country's other operators opted not to do so – but again, those sites are also the closest to the tri-plate action.
In hindsight, it might have been preferable to have projected beyond the hundred-year Richter sample, considering that a 8.9 quake unleashes 10 times the ground motion and releases about 32 times the energy of the planned-for "worst case" of a 7.9.

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By jason (registered) | Posted March 15, 2011 at 09:01:01

I agree with Ryan's assessment that much has been done right in Japan, not just at the nuclear plants, but everywhere. Their preparedness is amazing and should be a wake-up call to the rest of the world. However, I'm sure nobody reading this will volunteer to live next to a nuke plant designed to match these ones. The risks are just too high. The sooner we start taking advantage of cleaner energy sources like wind and solar, the better. I really feel for the workers who are still at these plants trying to stem a full meltdown. They are taking the brunt of the radiation exposure and my prayers go out to them and their families for their bravery, along with the rest of Japan as they face this enormous task of rebuilding.

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By Pxtl (registered) - website | Posted March 15, 2011 at 10:18:41

The nuclear reactors have maintained containment in spite of a disaster that killed over 10,000 people and destroyed entire cities. The primary containment is designed to withstand a full meltdown - according to experts, the reason they avoid a full meltdown is to ease clean-up and as a precaution. Two separate oil refineries burst into flames (the one at Chiba is still burning) and I imagine have had a far worse health impact than those plants.

I'm constantly disappointed how few news reporters are including millisieverts/millirems figures in their reports of venting and exposure. That's like reporting on a heat wave without mentioning the temperature, or a snowfall without reporting the height. For example, the "radioactive cloud" the USS Reagan went through exposed them to less radiation than you get from a single X-ray.

The workers have been exposed to comparatively high levels of radiation. Reports are conflicting, but some saying the peak radiation at the plant was 8mSv per hour, and some saying the exposure for workers at the peak was 0.5mSv per hour. 8mSv is about the same as what you get from a CT scan. All the numbers being bandied about so far have been far below the amounts that have been proven to cause any ill effect.

Obviously there are safety lessons to be learned from this mess, but when you compare this backdrop against the massive catastrophe that's covering Japan, it seems like nuclear safety has been a success story.

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By WRCU2 (registered) - website | Posted March 17, 2011 at 07:10:34 in reply to Comment 60973

By Pxtl:

...exposed them to less radiation than you get from a single X-ray.

Disinfo by design:

...the radiation in Ibaraki has reached 15,800 nanosieverts/hour at 11:40 am, which is 300 times normal. The spin: this is one third the amount of radiation in a chest X-ray. What is not mentioned is that an X-ray is exposure measured in one instant, whereas in this case the irradiation goes on for hour, after hour, after hour.

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By Ezaki Glico (anonymous) | Posted March 15, 2011 at 11:02:20 in reply to Comment 60973

A perspective shared over at The Register:

"Fukushima is a triumph for nuke power: Build more reactors now!"

http://www.theregister.co.uk/2011/03/14/fukushiima_analysis/

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By Ezaki Glico (anonymous) | Posted March 15, 2011 at 10:28:50

More on "acceptable risk"....

REUTERS

Special report: Big California quake likely to devastate state

By Peter Henderson

SAN FRANCISCO | Tue Mar 15, 2011 3:27am EDT

California will experience unthinkable damage when the next powerful quake strikes, probably within 30 years, even though the state prides itself on being on the leading edge of earthquake science.

Modern skyscrapers built to the state's now-rigorous building codes might ride out the big jolt that experts say is all but inevitable, but the surviving buildings will tower over a carpet of rubble from older structures that have collapsed.

Hot desert winds could fan fires that quakes inevitably cause, overwhelming fire departments, even as ancient water pipelines burst, engineers and architects say.

Part of the lesson from the disaster that hit Japan on Friday is that no amount of preparation can fully protect a region such as California that sits on top of fault lines.

Even so, critics fear the state may have long skimped on retrofitting older buildings. Yet the cost of cleaning up after a big quake is likely to be much higher than the cost of even the most expensive prevention, they warn.

"Everybody is playing a gamble that something like this won't happen," said Dana Buntrock, associate professor of architecture, at the University of California, Berkeley.


http://www.reuters.com/article/2011/03/15/us-quake-california-idUSTRE72E06220110315?WT.tsrc

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By Ricky (anonymous) | Posted March 15, 2011 at 10:43:32 in reply to Comment 60974

So what's the answer? Abandon the state and migrate en masse to Tahoe?

Some places are more risky than others but there are risks everywhere. It's just not possible to eliminate it - staying at home hiding under your coffee table gives you the real risk of muscle and bone degeneration, heart disease, diabetes, cancer.

A nuclear power plant is risky. A coal-fired power plant is even more risky, talk about radiation, pollution and lung/heart disease. Even solar power kills more people per kilowatt hour of production than nuclear power, after all you need to climb on the roof to install it and that's risky.

I'm not trying to be sarcastic, I don't have the answers either, but they're really hairy questions. It's easy to get hysterical about nuclear power because a meltdown is so scary but it's actually one of the safer ways of producting electricity. I'll give you this one though, it's probably not such a good idea to build nukes on fault-lines.

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By Ezaki Glico (anonymous) | Posted March 15, 2011 at 10:59:49 in reply to Comment 60975

That last point is all I've really been getting at – it strikes me as vaguely hubristic to incorporate "just enough" security measures when you're trafficking in nuclear and building on the edge of the earth's fickle maw.

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By Brandon (registered) | Posted March 15, 2011 at 12:17:09

Add in the fact that the company running the plants has a history of safety violations and just flat out lying.

http://crooksandliars.com/susie-madrak/s...

A sobering quote from the article:

Nuclear plants the world over must be certified for what is called "SQ" or "Seismic Qualification." That is, the owners swear that all components are designed for the maximum conceivable shaking event, be it from an earthquake or an exploding Christmas card from al-Qaeda.

The most inexpensive way to meet your SQ is to lie. The industry does it all the time. The government team I worked with caught them once, in 1988, at the Shoreham plant in New York. Correcting the SQ problem at Shoreham would have cost a cool billion, so engineers were told to change the tests from "failed" to "passed."

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By Ezaki Glico (anonymous) | Posted March 17, 2011 at 02:21:28 in reply to Comment 60981

Re: "Disaster Management"

NYT - Flaws in Japan’s Leadership Deepen Sense of Crisis

Excerpt:

Evasive news conferences followed uninformative briefings as the crisis intensified over the past five days. Never has postwar Japan needed strong, assertive leadership more — and never has its weak, rudderless system of governing been so clearly exposed. With earthquake, tsunami and nuclear crisis striking in rapid, bewildering succession, Japan’s leaders need skills they are not trained to have: rallying the public, improvising solutions and cooperating with powerful bureaucracies.

“Japan has never experienced such a serious test,” said Takeshi Sasaki, a political scientist at Gakushuin University. “At the same time, there is a leadership vacuum.”

Politicians are almost completely reliant on Tokyo Electric Power, which is known as Tepco, for information, and have been left to report what they are told, often in unconvincing fashion.

In a telling outburst, the prime minister, Naoto Kan, berated power company officials for not informing the government of two explosions at the plant early Tuesday morning.

“What in the world is going on?” Mr. Kan said in front of journalists, complaining that he saw television reports of the explosions before he had heard about them from the power company. He was speaking at the inauguration of a central response center of government ministers and Tepco executives that he set up and pointedly said he would command.

The chief of the International Atomic Energy Agency said late Tuesday in a press conference in Vienna that his agency was struggling to get timely information from Japan about its failing reactors, which has resulted in agency misstatements.

http://www.nytimes.com/2011/03/17/world/asia/17tokyo.html?ref=asia

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By GrapeApe (registered) | Posted March 15, 2011 at 12:35:54

Ryan, it appears we grew up in the same place. I recall sitting down at the beach (bottom of liverpool) and wading into lake ontario under shadow of the power plant. Also taking a small fishing boat out and looking back at all the reactors. Seems surreal now. One thing I recall is that the CANDU design should automatically cool itself in the even of a similar catastrophie. What design were the reactors in Japan?

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By Borrelli (registered) | Posted March 15, 2011 at 13:53:10 in reply to Comment 60982

Main diff between Canadian reactors and basically all other reactors is the moderating medium in which the fuel sits. As Ryan mentioned, Fukushima is a Boiling-Water Reactor which uses so-called "light water" (i.e. normal water).

CANDU reactors get their name from the heavy-water moderator (Canada Deuterium Uranium). Deuterium is an isotope of hydrogen (2H or D) that can replace hydrogen in water (H2O) to get so-called "heavy water" (D20).

The point of using a moderator like water in a reactor is to slow down reactions in the core, but D2O has the added advantage of not absorbing as many neutrons as normal water, thereby allowing CANDU reactors to use un-enriched uranium.

This in itself is a huge design difference--enriching uranium is a complex and expensive task, and using enriched uranium leaves undesirable byproducts like plutonium.

As well, there are safety benefits from using heavy water in CANDU reactors, and I'm not sure I can explain those benefits very succinctly, but here's a good overview:

Comment edited by Borrelli on 2011-03-15 13:55:55

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By Mr. Meister (anonymous) | Posted March 17, 2011 at 22:28:00 in reply to Comment 60985

The big difference between Candu reactors and others is that the Candus use un-enriched uranium while all the others use enriched uranium. The Candus need to use heavy water to allow enough neutrons to get through to maintain the critical mass. Plain water would absorb to many neutrons and stop the fission process.

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By MattM (registered) | Posted March 15, 2011 at 12:56:40 in reply to Comment 60982

"Units 1–5 were built with Mark I type (light bulb torus) containment structures, Unit 6 has a Mark II type (over/under) containment structure."

http://en.wikipedia.org/wiki/Fukushima_I...

Comment edited by MattM on 2011-03-15 12:57:12

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By Undustrial (registered) - website | Posted March 15, 2011 at 14:18:19

The nuclear reactors have maintained containment in spite of a disaster that killed over 10,000 people and destroyed entire cities.

As far as we knew, at least two days ago, we had not yet lost containment. It is now widely suspected that at least one reactor has or will.

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

And there is no offical word of a death toll anywhere near 10 000. Last I've seen it's climbed to a third of that. If we're going to lowball every estimate of death tolls from nuclear power, then lets not assume the worst everywhere else. That's exactly how people come to conclusions like "nuclear power kills less people than solar". How are those statistics arrived at? Do they take into account the concequences of uranium mining and processing (knowing many oncologists, I've heard many a story about cancer-rate cover-ups)? Increased risks of nuclear proliferation? Long-term risks of nuclear waste? Do they assume, like many lately, that Chernobyl only actually killed fifty-something people?

Through normal operation, many coal plants do kill far more people than nuclear, and also emit a fair amount of radiation. But that is true among very easily quantifiable numbers, and it's true only if nuclear plants perform as intended and claimed. It's like cigarettes and handguns. Cigarettes harm you every time you use them, but a handgun only has to do it once.

Could it be worse? Yes. But it could always be worse. That doesn't prove that it's "ok". We won't know that it's ok until we've seen serious evidence in peer-reviewed journals from those without obvious conflicts of interest. Much of the data needed won't even be available for years to come (health studies of the children of pregnant mothers in the area, etc).

The workers on site at the plant better get statues. They're the heroes here.

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By Caligula (anonymous) | Posted March 18, 2011 at 08:52:13 in reply to Comment 60988

"And there is no offical word of a death toll anywhere near 10 000."

Official death toll is already over 6,000 and over 10,000 people are still missing. The final death toll will be well over 10,000.

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By Caligula (anonymous) | Posted March 18, 2011 at 09:04:47 in reply to Comment 61144

Sorry, make that 7,000 confirmed dead, 20,000 dead or missing.

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By calmdown (anonymous) | Posted March 15, 2011 at 14:36:37

With all the fear-mongering BS out there (I'm looking at you network television!) this was a refreshing summary of what's going on.

The worst part has been listening to these reporters interviewing nuclear power experts and asking these stupid paranoid leading questions.

TV Reporter: So has the reactor explosion exposed people to dangerous levels of radiation?

Expert: (sighing) The reactor didn't explode. It was just the buil-

TV Reporter: Do people in California have to worry about fallout from wind blowing across the Pacific?

Expert: Well, no, I mean any radiation released so far is extremely short-lived, on the order of secon-

TV Reporter: But isn't it a possibility?

Expert: (getting annoyed) Well anything's possible, the situation is still developing and we don't know everything yet. But it's clear they're doing a good jo-

TV Reporter: There you have it, another expert warning that the worst is still possible in the Japanese nuclear reactor disaster. Over to you, Brett, with the weather.

There's a reason journalists went into journalism and not atomic physics, know what I mean?

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By Ezaki Glico (anonymous) | Posted March 17, 2011 at 02:14:02 in reply to Comment 60990

A United Nations forecast of the possible movement of the radioactive plume coming from crippled Japanese reactors shows it churning across the Pacific, and touching the Aleutian Islands on Thursday before hitting Southern California late Friday.

Health and nuclear experts emphasize that radiation in the plume will be diluted as it travels and, at worst, would have extremely minor health consequences in the United States, even if hints of it are ultimately detectable. In a similar way, radiation from the Chernobyl disaster in 1986 spread around the globe and reached the West Coast of the United States in 10 days, its levels measurable but minuscule.

http://www.nytimes.com/2011/03/17/science/17plume.html?_r=1&hp

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By Do not like nuclear (anonymous) | Posted March 15, 2011 at 15:24:30

I guess to me, we should all be looking at the amount of power consumption we all use daily. I find nuclear energy dangerous for many reasons. Of course, people do not want to really look at things in their proper perspective.

There is no easy answer but there is a need for some honest reflection and answers. We are all part of the problem in one way or another.

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By jason (registered) | Posted March 15, 2011 at 23:02:00

not looking good right now.... http://www.thestar.com/news/world/articl...

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By jason (registered) | Posted March 16, 2011 at 09:41:10 in reply to Comment 60999

workers are back at the plant today. Let's hope radiation levels have dropped significantly. These guys are risking their lives for the greater good. Pretty amazing.

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By Michelle Martin (registered) - website | Posted March 16, 2011 at 11:36:40 in reply to Comment 61003

These guys are risking their lives for the greater good. Pretty amazing.

Yes- when the disaster management plan hasn't covered everything, we do need heroes to step into the breach. And thank God for them...

The Japanese government has passed an emergency regulation that doubles the "allowable" level of radiation exposure for nuclear plant workers.

--Zot, below

...though it looks like some are stepping up to the plate whether they want to or not.

Mama, don't let your babies grow up to be nuclear power plant employees...

Comment edited by Michelle Martin on 2011-03-16 11:47:27

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By nobrainer (registered) | Posted March 16, 2011 at 10:42:42 in reply to Comment 61003

I read that the evacuation was actually a mis-translation by English reporters of what the Japanese government said. Damn I wish we could get better information about what's going on...

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By Zot (anonymous) | Posted March 15, 2011 at 23:06:04

As of 11:00 pm Tuesday Hamilton time the Associated Press is quoting Chief Cabinet Secretary Yukio Edano as saying that all the remaining plant workers who have been attempting to control the accident are being withdrawn from the site due to high radiation levels.

An attempt to cool the spent fuel ponds by water drops from helicopters is still under consideration...

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By tanaka (anonymous) | Posted March 16, 2011 at 02:49:53

Chain of events to come:
1.Fukushima really goes kaboom !!!!
2.massive evacuation takes place
3.After a couple months, radiation level drops to normal, everybody returns (after all this is nothing like Chernobyl, right?)
4.Years later, everybody got cancer ????
5.oops!!! Apparently we forgot to evacuate the fishes in the sea, the cabbage on the ground, an of course no one told the whales to take a slight detour

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By MattM (registered) | Posted March 16, 2011 at 09:09:54 in reply to Comment 61001

  1. Nuclear plants do not go boom.

  2. Evacuations are already happening.

  3. Radiation doesn't just "go away". The situation will be "like chernobyl" so long as a complete meltdown occurs.

  4. Yes, they will.

  5. What is this I don't even

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By Zot (anonymous) | Posted March 16, 2011 at 11:29:55

Wednesday updates:
The Japanese government has passed an emergency regulation that doubles the "allowable" level of radiation exposure for nuclear plant workers.
The utility has returned 100 workers to the site, following an evacuation yesterday due to excessive radiation levels.
The utility is reporting that the pressure vessel of the #3 reactor ruptured today, and that the pressure vessel of #2 reactor ruptured yesterday due to an internal hydrogen explosion. The rupture at #3 required the workers to shelter on site due to a radiation spike, but they did not evacuate.
Yukio Edano, the chief cabinet secretary, has said today that it is "unlikely" that the ruptures in the pressure vessels are "severe", at the same time the Utility is saying that they are unable to get close enough to assess conditions inside the damaged reactor buildings due to high radiation levels.
Plans to drop water on the spent fuel pool in #4 reactor using helicopters have been rehearsed, but are on hold. Radiation levels in the steam cloud above #4 pose an unacceptable risk to the helicopter aircrews at the present time.
Japans supply of Boron, which has been being mixed with the emergency cooling water, is close to being depleted. South Korea has said it will ship 52 tons of Boron to Japan from its 310 ton emergency stockpile to aid in the relief efforts.
France and Germany are advising their nationals to leave the Tokyo area.
The American and French navy are reevaluating details of their assistance to the accident site due to contamination levels of American carrier based aircraft.

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By Undustrial (registered) - website | Posted March 16, 2011 at 12:39:35

Say goodbye to nuclear power. One reactor in crisis is enough to spook the better part of a continent - ten reactors in crisis? That's a sign.

Anyone, from this point onward, who wishes to build a new nuclear power plant anywhere near here is going to have to physically remove me from the site first. And I won't be alone.

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By MattM (registered) | Posted March 16, 2011 at 13:19:59 in reply to Comment 61008

It's definitely far too premature to be saying things like "goodbye nuclear power". Lets wait until this thing plays out.

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By nobrainer (registered) | Posted March 16, 2011 at 13:26:13 in reply to Comment 61010

Maybe "goodbye nuclear power built on top of an earthquake fault" is a place to start that we can all agree on.....

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By MattM (registered) | Posted March 16, 2011 at 13:54:40 in reply to Comment 61011

That would effectively be a goodbye to nuclear power in Japan, which is definitely a very difficult issue given Tokyo's air quality issues. Fossil fueled plants are obviously not an option.

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By Undustrial (registered) - website | Posted March 16, 2011 at 17:10:52 in reply to Comment 61012

How would Japan power itself without nuclear? Seems to me that both tidal and geothermal have a fair bit of possibilities. Coal isn't the only other option.

A more pressing question than "where are we going to get all this energy?" would be "why are we using all this energy in the first place?"

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By zot (anonymous) | Posted March 16, 2011 at 16:24:54

For those of you interested in the science of nuclear fukcups you might want to check out this paper published by Los Alamos National Labs in the year 2000:

"A Review of
Criticality Accidents, 2000 Revision"
http://www.orau.org/ptp/Library/accidents/la-13638.pdf

It describes about 60 incidents over the years at labs and nuclear facilities of various sorts where nuclear chain reactions started by accident. 8-(

Gives an interesting look at how in the real world this stuff will bite you in the ass if given half the chance

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By Undustrial (registered) - website | Posted March 16, 2011 at 20:45:15

Interesting note from today, the Pickering plant released 72 000 litres of water from the reactor, and an earthquake hit in the unstable Ottawa region, though the (notorious) Chalk River facilities appear to be unharmed.

That's just today, and just Ontario.

http://beyondmacgyver.wordpress.com/2011...

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By Zot (anonymous) | Posted March 16, 2011 at 21:01:06 in reply to Comment 61017

Relax, as my old Commanding Officer used to say: "Gentlemen: You have been supplied with the best equipment the lowest bid can buy."

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By Zot (anonymous) | Posted March 16, 2011 at 22:38:20

Wed. evening updates:
NHK Japanese TV is now broadcasting water bombing of the #3 reactors storage pool.
Due to high radiation levels the heavy lift helicopters, which have had lead radiation shields attached to them, are unable to hover over the building while doing the drop, but rather are dropping while on the move over the building at an altitude of 300 meters. Also they are limited to 40 minutes per aircraft over the target before they hit their maximum radiation exposure limit.
A total 30 tons of water was dropped prior to operations being suspended. It looked to me like most of the water was missing the building completely.
Police riot control trucks equipped with water cannon are now on route to the site, they will attempt to spray water into the building through the holes in the walls that have been created by the hydrogen explosions that have occurred on the site.
In a press conference the Utility said that water levels are dropping, and pressures are rising in the #5 reactor on the site, which up to now has not shown serious problems. Also cooling problems are beginning to develop in the spent fuel storage at the #5 and #6 reactors.
They also explained that the coolant pumps installed in the complex were not designed to pump salt water and have been damaged by corrosion during the pumping of sea water during the emergency. Salt water capable pumps have been supplied, and are now in the process of being installed.

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By Ezaki Glico (anonymous) | Posted March 17, 2011 at 08:42:58

“This is definitely in the Chernobyl league now,” Frank von Hippel, a nuclear physicist at Princeton University, told The Christian Science Monitor. “If the reactors go, that’s bad, of course. But the real concern at this point is if those...spent-fuel pools catch fire. There are many Chernobyls’ worth of radioactive material in there.”

http://www.allgov.com/Top_Stories/ViewNews/Japan_Reactor_Emergency_Passes_Three_Mile_Island_on_Scale_of_Nuclear_Disasters_110317

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By MattM (registered) | Posted March 17, 2011 at 11:28:41

Starting to lose my hope of this situation getting better... I really hope they can get that power line connected and get the pumps going today.

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By TB (registered) - website | Posted March 17, 2011 at 14:14:55

Meanwhile "the Harper Government" has just arranged for buses to take Canadians a few kilometers south out of immediate danger. After that they're on their own. Most other countries have arranged charter flights to get their citizens out of the country, starting several days ago.

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By Zot (anonymous) | Posted March 17, 2011 at 19:42:52

Bloomberg online is reporting at 2:00 today that passengers arriving at Dallas-Fort Worth and Chicago O’Hare airports this afternoon from Tokyo triggered radiation security alarms when they disembarked and entered the airport.
Further testing at Dallas showed low level radioactive contamination on passenger luggage and on particles trapped in the aircraft cabin air filters.
No passengers were detained at the airport.
Tokyo is about 220 km from the damaged reactors.
A "No Fly" zone for civilian aircraft has been in in effect in the vicinity of the reactors since early yesterday.

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By Caligula (anonymous) | Posted March 18, 2011 at 09:04:25

Hopefully Tepco workers will be able to get main power back on to the reactors at Fukushima Dai-ichi and restart the main generators by Sunday. If that works, all we have to do is cross our fingers and hope all the salt water they've been flushing through the reactors don't corrode the pumps so much that they break down....

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By Zot (anonymous) | Posted March 18, 2011 at 15:01:40 in reply to Comment 61145

They have the power cable to the plant now, but radiation levels are too high to allow them to get close enough to connect it to the plant equipment...

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By TB (registered) - website | Posted March 18, 2011 at 17:15:44 in reply to Comment 61173

Where are the robots?

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By Zot (anonymous) | Posted March 18, 2011 at 18:54:15 in reply to Comment 61183

Short answer: They don't exist.

Longer answer:
Problem 1 - Unlike in science fiction movies we are just now getting to the point of building robots that can do things like climb stairs and ladders, turn valves, etc. Under ideal conditions often laid out with robots in mind. In this case we are talking about a blast damaged work area no doubt full of hunks of concrete, broken structural steel, etc. designed in the 1950's before robots existed. It's still a difficult technical problem.

Problem 2 - This is a high radiation environment, and radiation fries much off the shelf solid state electronic equipment such as is found in many robots even faster than it fries human nervous systems. If you think about it a human cell is a lot bigger than a single device on a computer chip, it can take more radiation hits in some cases prior to failing.
Shielded or rad hardened devices can be built though, they are found in the space program, were eventually used at 3 mile island, and Chernobyl, but they were custom jobs not avalable "off the self" Why? well:

Problem 3: - They have not been built ahead of time because there is no need. The plant was built to a design which covers all concievable risks, it will not fail, therefore it is a total waste of money. To build them would be to admit that there might be a problem with the safety standards of the design. And there is no problem with the design, the plant is safe, We have know this for years and keep telling you that, why don't you believe us, we are experts who know what we are talking about....

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By SpaceMonkey (registered) | Posted March 20, 2011 at 15:24:06 in reply to Comment 61187

They do exist. Some uranium mining companies use remote controlled machinery to mine uranium.

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By TB (registered) - website | Posted March 19, 2011 at 09:17:01 in reply to Comment 61187

Surgeons wield scalpels remotely now. I don't think it's science fiction to imagine a machine turning valves, dragging fire hoses and manipulating other equipment. Think of a shielded tank-like Mars Rover capable of maneuvering in very rough terrain. We shouldn't have to put humans anywhere near the danger zone. All of the required technology exists. Maybe now Honda and others will redirect their efforts.

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By Zot (anonymous) | Posted March 19, 2011 at 17:38:49 in reply to Comment 61191

For a chilling look at true heroes check this video of the Chernobyl cleanup effort:
http://video.google.com/videoplay?docid=-5384001427276447319#

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By Undustrial (registered) - website | Posted March 19, 2011 at 12:22:32 in reply to Comment 61191

Even without robots, our society builds a lot of tanks, tractors and bulldozers which could be modified. Rad-shield the electronics, lead-shield the cabins, and equip them with what's needed to clear debris and spray water or sand if needed.

I'm sure it's possible. But work would have needed to start many years ago. For now, we're stuck with humans.

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By TB (registered) - website | Posted March 23, 2011 at 17:56:43 in reply to Comment 61196

Radiation Detector Robots: http://www.pcworld.com/article/222947/ra...

Comment edited by TB on 2011-03-23 17:57:35

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By Zot (anonymous) | Posted March 23, 2011 at 20:26:34 in reply to Comment 61429

"Other robots in Japan were also developed for helping out in case of a nuclear emergency after the Tokaimura disaster. However, none of these were ever adopted because, according to The New Scientist, the "nuclear industry claimed that their plants were safe".

See "Problem 3" in my original post upthread...

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By Zot (anonymous) | Posted March 18, 2011 at 14:47:55

Some officials in Japan are coming unstuck today, others are making heroic pronouncements.

Tokyo Electric Power Company Managing Director Akio Komiri broke down in tears as he left his daily press conference in Fukushima today:
http://i.dailymail.co.uk/i/pix/2011/03/18/article-1367684-0B3BF1E700000578-880_472x491.jpg
after admitting that radiation escaping the plant is at potentially lethal levels, that the authorities should have been more open in disclosing the magnitude of the accident, and that entombing the complex in sand and concrete, as was done at Chernobyl, may be the only way to prevent massive releases of radiation.
Given the current high radiation levels at the plant, the condition of the reactor buildings, and the sheer size of the complex, I have not seen any practical suggestion as to how such a thing could be done in time, even if the decision was made to attempt it, but maybe I'm missing something?

In a televised speech today conference prime minister Naoto Kan insisted that his country would overcome the catastrophe:

'We will rebuild Japan from scratch. In our history, this small island nation has made miraculous economic growth thanks to the efforts of all Japanese citizens. That is how Japan was built.'

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By MattM (registered) | Posted March 18, 2011 at 16:25:40

That was a really nice statement at the end there, to cap off some pretty devastating news.

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By scree (anonymous) | Posted March 21, 2011 at 10:12:13

Now there's white smoke pouring out of reactor 2 and black smoke pouring out of reactor 3. Two steps forward, one step back...

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By context (anonymous) | Posted March 21, 2011 at 11:52:33

I couldn't say it better myself.

http://blogs.telegraph.co.uk/news/jamesdelingpole/100080636/japan-whatever-happened-to-the-nuclear-meltdown/

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By realitycheck (anonymous) | Posted March 21, 2011 at 12:22:11

This editorial does an excellent job of putting the magnitude of the crisis in proper perspective:

http://www.vancouversun.com/news/Opinion+realistic+nuclear+option+safer+than+fossil+fuels/4474439/story.html

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By TB (registered) - website | Posted March 21, 2011 at 17:44:06 in reply to Comment 61284

I wouldn't be at all surprised if nuclear energy generation will in fact be far cleaner and safer than all other options, particularly after we've learned how to manage it and the waste properly, but for the author to claim statistics like "27 people will die prematurely from exposure to particles emitted in the upper atmosphere by passenger aircraft flying at 35,000 feet" is nothing short of absurd and he loses all credibility as a result in my view.

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By MattM (registered) | Posted March 22, 2011 at 09:02:32

Power has been reconnected to all 6 reactors but TEPCO needs to check the pumps and make sure there is no gas build up before the system can be restarted. If nothing new crops up, looks like this situation can finally be considered under control again. Units 5 and 6 are completely cooled and shut down, no threat of any problems as their cooling systems are working as intended once again.

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By Zot (anonymous) | Posted March 22, 2011 at 23:25:48

Tuesday updates:
After a day spent working on #2 reactor now that electrical power has been restored workers have apparently been successful in getting the lighting in one of the control rooms back on...
The Utility, TEPCO confirms that the cooling pumps for #2 reactor have been destroyed.
Release of thermal imaging of the complex by NHK television has led to TEPCO revising its description of the state of the reactors.
Reactor #1, which TEPCO had previously described as having been brought to "Cold Shutdown" i.e. less than 100 deg C., was in fact today at a temperature of 380-390 deg.C, which is in excess of it's normal temperature when running at full power (302 deg. C)
The #4 reactor was seen to be in the range of 500 deg C to 1,000 deg C today. (saturation of the infrared camera made a more accurate reading unavailable)
The primary containment vessels of the reactors are made from alloy 316 stainless steel, which displays a noticeable loss of strength at 800 deg. C and melts at about 1380 deg. C
Temperatures in the #3 spent fuel pool were 130-160 deg C, confirming exposure of the MOX fuel to the air despite the ongoing water spray operations.
Workers on the site were forced to evacuate again today when on site radiation levels spiked to 500 mSv/hr. 10 hours exposure at this dose rate would impart what is generally considered to be a fatal human dose of 5 Sv.
Bloomerg news broke a story today describing the cover-up of significant defects in the primary containment vessel of the #4 reactor at the time of its manufacture in 1974.
http://www.bloomberg.com/news/2011-03-23/fukushima-engineer-says-he-covered-up-flaw-at-shut-reactor.html
In the story Robert Ritchie, Professor of Materials Science & Engineering at the University of California of Berkeley, is quoted as saying in a phone interview: “These procedures, as they’re described, are far from ideal, especially for a component as critical as this,” ... “Depending on the extent of vessel’s deformation, it could possibly lead to local cracking in some its welds.”


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By Zot (anonymous) | Posted March 23, 2011 at 05:53:02 in reply to Comment 61381

Correction: It's reactor #3 control room that now has the lights on, not reactor #2. As of 6:00 am Wed. our time NHK tv is showing the #3 control room as being uninhabitable due to high radiation levels.

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By Ezaki Glico (anonymous) | Posted March 23, 2011 at 10:18:37

Even with the plants under control, panic may be harder to douse...

"Infants in Tokyo and five surrounding cities should not be allowed to consume tap water, the city's government said Wednesday after elevated levels of radioactive iodine from a crippled nuclear plant were detected at a water treatment plant.

Japan's Prime Minister Naoto Kan urged consumers to not eat a dozen types of contaminated vegetables from the region surrounding the nuclear facility 150 miles northeast of the capital and also expanded a shipment ban."

http://www.latimes.com/news/nationworld/world/la-fg-japan-tokyo-water-20110324,0,7951826.story

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By Zot (anonymous) | Posted March 23, 2011 at 15:09:21

Putting the contaminated water issue in perspective:
The contamination is measured in a unit called a Becquerel (symbol: Bq)
Definition: 1 Bq is the amount of radioactive material necessary to produce 1 radioactive decay per second.

Levels: In Japan the "safe" limit in drinking water for infants is 100 Bq per litre. The levels now being seen in Tokyo water are about 250 Bq per litre. So 1 litre of the "hot" water will produce 250 radioactive decays per second. Is that "a lot"?

Biological background: The environment is full of naturally occurring radioactive material. In Human tissue the vast majority of it consists of radioactive Carbon, C14, and radioactive Potassium, K40.
A 70 kg human body contains about 4,400 Bq of K40 and 3,700 Bq of C14, for a total of 8,100 Bq. Dividing this by 70kg we get a natural radioactivity level of human tissue of about 116 Bq/kg.

So, the present levels in Tokyo water are less than twice what is present in "uncontaminated" human tissue.

That said there is of course the possibility that if things deteriorate at the reactors the fallout problem could become much more acute...

(Source for reference values quoted: "Handbook of Radiation Measurement and Protection", Brodsky, A. CRC Press 1978)

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By Zot (anonymous) | Posted March 24, 2011 at 12:33:56

"Venting the air and draining the water requires a technician to reach a dozen valves, sometimes using a ladder. ..." Heh, now probably a bulldozer and a lead lined jockstrap as well.

Thursday updates:
Electrical power has been restored to the control room of the #1 reactor.
High radiation levels on site continue to interfere with workers ability to access much of the facility.
Two Electricians taking part in efforts to restore electric power to the damaged reactors were taken to hospital today after suffering prompt beta particle radiation burns to their feet and lower legs. The injuries apparently occurred when the workers stepped in puddles of highly contaminated water on the site.
Beams of Neutron radiation of unknown origin are periodically being detected at the site. Significant levels of Neutron radiation are produced by fission chain reactions, not by decay of fission products. This would thus suggest that fission is occurring in the supposedly shut down reactor cores and that the primary containment of those cores is breached, and / or that a chain reaction is occurring outside of the reactors, for instance in the spent fuel pools or in the radioactive soup in the lower levels of the damaged reactor buildings. This is really not good news for repair efforts should it persist. Being in the vicinity of an unshielded chain reaction can impart a fatal radiation dose in a matter of seconds.
White smoke or steam is now escaping from reactors 1 through 4.
Problems are now developing at the #5 and #6 reactors, which up until now have been in a "stable" cold shutdown state. Cooling to the #5 reactor was lost yesterday during a swap out of cooling pumps. Efforts to restore cooling to #5 are continuing today. Radioactive Iodine and Cesium are now present in drainage from both #5 and #6 reactors, indicating failure of containment either in the reactor or the spent fuel pools.

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By MattM (registered) | Posted March 24, 2011 at 13:13:25

Argh. Just when it looks like things are doing alright...

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By Zot (anonymous) | Posted March 24, 2011 at 18:04:53

Building water crisis in Tokyo:

For the past 2 days the Japanese government has been broadcasting public service messages on radio and television in the Tokyo area urging residents "not to panic and not to horde bottled water."
Predictably, retail stores are now sold out of bottled water.
The government is now announcing plans to distribute a ration of 24 oz. (2 beer bottle sized containers) of bottled water per day for each registered infant under the age of 1 year. This will entail the distribution of 240,000 bottles of water per day.
If it became "necessary" to provide emergency drinking water rations at survival levels for all people currently within the contaminated drinking water zone distribution of on the order of 100,000,000 (one hundred million) 12 oz bottles of water per day would be required. By way of comparison the entire United States consumes about 86 million bottles of bottled water per day.
I have not heard anyone suggest that a bottled water distribution on this scale would be possible given the current conditions in the country.


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By Zot (anonymous) | Posted March 25, 2011 at 00:03:59

Thurs. p.m. update:

Officials in Tokyo city are now saying on NHK television that contamination levels in the tap water have dropped from 250 bq/Litre to a current level of 79 Bq/Litre and so is now "safe" for everyone including infants to drink.
Drinking water restrictions and plans for emergency distribution of water for infants remain in effect in Chiba, Saitama, and Ibaraki prefectures.
Government spokesmen say they are "considering" importing bottled water from overseas.
I can't find any mention at all of the current situation regarding drinking water problems on the English (or as far as I can tell the Japanese) language versions of the Tokyo municipal government website or the Tokyo water utility website.

Teaching moment: Don't count on government websites as a useful source of information in future emergency situations if the Japanese example is anything to judge by.
Information in mainstream media is at least 90% targeted at Sheeple with an elementary school level of conditioning.
http://thetruth.dontexist.net/O/sheeple.gif
Best sources of actual information on this story, as with just about anything of actual importance, is to be found in the "business" media.


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By pirateboy (anonymous) | Posted March 29, 2011 at 00:14:17

Wow, you folks really know what you're on about (with a few exceptions)! The earthquake and tsunami are bad enough alone, but since some wank job thought nuclear power on a fault line was a good idea, they have this nuclear disaster crap to contend with. Nuclear power, no matter where you are, is a bad idea. Sure, it doesn't use fossil fuels, and sure, it has low carbon emmisions, and yes, it is efficient. But, nuclear is very high maintainance, highly complicated, is comparably unreliable, and when a reactor does fail, the consequences are irrepairable (you can't fix or re-build a reactor) and often catastrophic. Coal, which nuclear supporters say is more dangerous and emits more radiation, actually has a much better track record than nuclear. Sure, the ash might openly produce more background radiation, but how many radiation deaths have occured because of coal? And if nuclear really is safer, why don't exploding coal plants produce fallout resulting in mass evacuations and massive exclusion zones being indefinitely placed? Now i'm not advocating coal here, i'm just saying it's safer than nuclear.
I propose strategic renewable energy placement. Japan can do this successfully without the need of the 50-odd nuclear plants installed. Strategic placement like geothermal in volcanically active areas, tidal power in rough areas, wind in windy areas, japan has every opportunity to exploit their diverse climate to meet demands.

As with wind, google tesla wind turbine: some bloke built a wind turbine the size of a motorbike trailer capable of producing 10Kw! Nuclear may have met it's match.

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By Ezaki Glico (anonymous) | Posted April 03, 2011 at 11:42:42

Crews 'facing 100-year battle' at Fukushima
http://www.abc.net.au/news/stories/2011/04/01/3179487.htm

"A nuclear expert has warned that it might be 100 years before melting fuel rods can be safely removed from Japan's Fukushima nuclear plant. The warning came as levels of radioactive iodine flushed into the sea near the plant spiked to a new high and the Wall Street Journal said it had obtained disaster response blueprints which said the plant's operators were woefully unprepared for the scale of the disaster."

Fukushima 50 'know they are going to die'
http://www.thisislondon.co.uk/standard/article-23937733-fukushima-50-know-they-are-going-to-die.do

"They have concluded between themselves that it is inevitable some of them may die within weeks or months. They know it is impossible for them not to have been exposed to lethal doses of radiation."

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By pirateboy (anonymous) | Posted April 11, 2011 at 23:03:58

Just heard on the classic rock station this morning that the disaster has bin raised to 7. That's some real chernobyl stuff right there!
This occurred after yet another quake. I've also bin seeing much more asians, possibly japanese, settling into my current home town of katoomba. This is dire indeed. Japan should consider mothballing all their nuclear plants; even the great japanese engineers couln't prevent this. I really hope the government decides against nuclear for australia, i don't want an incident like that here.

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By sathya narayanan (anonymous) | Posted April 20, 2011 at 05:23:06

Nuclear Power in Canada
Canada has 18 active CANDU reactors operating at five sites, most of them in Ontario, that produce 15 percent of Canada's electricity (and 50% of Ontario's electricity). The Province of Ontario is planning to build another reactor, either at Bruce Nuclear Station or Darlington Nuclear Station.

I grew up in sight of the Pickering Nuclear Station. We used to wade up Duffin's Creek and fish in Frenchman's Bay. In winter, we used to toboggan on the hills at Brock Rd. and Montgomery Park Rd. in front of the reactors.

I must admit to a visceral aversion to nuclear power, doubtless spurred in part by a childhood in the paranoid 1980s at the height of hostilities between the USA and the USSR. Still, I try to make policy decisions based on a sound understanding of the facts rather than blind fear.

Again, I'm surprised to find myself somewhat heartened by how well the Fukushima I plant has survived the massive traumas to which it has been subjected. Canada's nuclear facilities, in contrast, are situated in geology that is orders of magnitude safer.

On the other hand, I'm left wondering whether we can trust our government officials to maintain the same obsessive commitment to safety engineering as their

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