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Tepco engineers use concrete to seal leaks  (Source: TEPCO)
The top five feet of the core's 13 ft-long fuel rods had melted down after being exposed to the air

The Tokyo Electric Power Company (Tepco) has announced that the No. 1 reactor at the Fukushima Daiichi nuclear power plant has suffered a nuclear meltdown.

The Fukushima Daiichi nuclear power plant was first commissioned in 1971 and is located in the Futaba District of Fukushima Prefecture, Japan. On March 11, 2011, a 9.0-magnitude earthquake struck Japan, resulting in the disabling of reactor cooling systems, radiation leaks and an evacuation zone. 

Engineers from Tepco entered the No. 1 reactor for the first time at the end of last week and found that the top five feet of the core's 13 ft-long fuel rods had melted down after being exposed to the air. 

Engineers originally thought only 55 percent of the core was damaged since it was submerged in enough water to keep cool and stable, but after discovering a pool of molten fuel at the bottom of the containment vessel, they now worry that this molten fuel burned a hole at the bottom of the vessel prompting water to leak. 

Tepco recently sealed a leak at the No. 3 reactor after radioactive water had seeped into the ocean. Also, the No. 2 reactor had radioactive water flowing into the ocean in April. According to Greenpeace, "significant amounts" of radioactive material had slipped into the sea. In fact, illegal amounts of iodine and caesium were found in seaweed as far as 40 miles from the Fukushima Daiichi plant. 

In 22 samples of seaweed, ten contained five times the legal limit of iodine 131 and 20 times of caesium 137. This is an issue for several reasons, including the fact that the Japanese household consumes almost 7 lbs of seaweed annually, and fisherman are preparing to harvest this seaweed on May 20. 

Engineers have decided to quit flooding the entire reactor core with water because it might make the leak worse. Currently, there is plenty of water at the bottom of the containment vessel to keep the remaining fuel rods and the melted fuel cool. 

"We will have to revise our plans," said Junichi Matsumoto, Tepco spokesman. "We cannot deny the possibility that a hole in the pressure vessel caused water to leak."

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*Partial* meltdown
By Slyne on 5/13/2011 6:23:26 PM , Rating: 5
Well, this is more a confirmation than a newsflash. I think using the past tense and precising *partial* meltdown would make the article look a little more professional. The possibility of a partial meltdown had been considered already 2 months ago after traces of Cesium were found (

Still, this sucks

RE: *Partial* meltdown
By sr1030nx on 5/13/2011 6:52:51 PM , Rating: 5
I have to agree with you here.
There's too many so-called professionals who exaggerate facts purposely and state their personal opinions as facts.
Not enough journalists (or media companies as a whole) with actual integrity.

RE: *Partial* meltdown
By borismkv on 5/13/2011 7:45:05 PM , Rating: 5
I read a study while I was in college (considering a journalism career) that showed the majority of Journalism students wanted to go into journalism because they felt it would allow them to influence peoples' opinions. I could only think, "Isn't that the exact opposite of what a good journalist does?"

RE: *Partial* meltdown
By dark matter on 5/14/11, Rating: -1
RE: *Partial* meltdown
By FITCamaro on 5/15/2011 5:45:51 PM , Rating: 1
A well put argument.

Most of us don't give a crap about other people's opinions. We just want others to live their lives in a way that doesn't affect us as we try to.

RE: *Partial* meltdown
By SPOOFE on 5/15/2011 11:57:34 PM , Rating: 3
How could you be passionate about anything and NOT want to change peoples minds.

By being passionate about accurate information and the presentation thereof. That's what good journalism is. If you want to change people's minds, you don't want to be a "journalist". You want to be a "marketer".

We all want people to agree with us, or even better, change their opinion to ours.

Incorrect. I find there are few feelings quite as sublime as encountering an argument so well put and so well supported that it makes me abandon my previous position without reservation.

RE: *Partial* meltdown
By FITCamaro on 5/15/2011 5:44:27 PM , Rating: 2
No its the opposite of what a journalist is SUPPOSED to do.

RE: *Partial* meltdown
By Azethoth on 5/15/2011 12:10:48 AM , Rating: 4
Wrong. Meltdown is meltdown. Partial vs Full you can argue over but simply stating meltdown is correct and in no way alarmist.

RE: *Partial* meltdown
By Hoser McMoose on 5/15/2011 9:38:11 PM , Rating: 1
"Partial meltdown", "full meltdown", or whatever other type of "meltdown" you wish to describe, doesn't have any proper meaning. That is why the term is never used in any technical description, it just doesn't accurately describe anything.

It's used in movies and by the media to generically describe any sort of problem with any sort of nuclear equipment that has had any sort of "melting" (for a variety of definitions of "melting").

So really calling it a "partial meltdown" or a "full meltdown" is equally accurate and also equally useless for describing what is actually happening.

RE: *Partial* meltdown
By SPOOFE on 5/16/2011 12:01:15 AM , Rating: 4
That's like saying the term "car crash" is useless, because it can mean anything from a fender-bender all the way up to an 80-car pile-on.

Nope; the melting of nuclear fuel is about the worst thing that can happen in a nuclear reactor. As such, the term "meltdown" has a hell of a useful meaning. It's just not very pleasant.

RE: *Partial* meltdown
By CZroe on 5/13/2011 9:17:52 PM , Rating: 2
I, too, read the headline and started thinking that a real melt down had occurred. I'm not sure, but I think a "melt down" is more than just fuel melting combined with radioactive water leaking. I believe it specifically refers to fuel melting it's way out of the containment vessel entirely, like what happened at Chernobyl after the explosion (fuel now site exposed in a frozen glass-like state below the reactor chamber's original location). It doesn't sound like that happened here at all.

RE: *Partial* meltdown
By Angstromm on 5/14/2011 3:22:18 AM , Rating: 2
Actually, "meltdown" refers to core melt, partial or otherwise. And it's not what would be called a sanctioned term with a clear cut definition used by various nuclear regulatory agencies.

RE: *Partial* meltdown
By Peter898 on 5/14/2011 3:25:49 AM , Rating: 4
No it isn't and no it doesn't, a 'meltdown' is exactly that, the melting of nuclear fuel due to insufficient cooling .
It doesn't have to leave the containment or burn it's way to China (well, in the case of Japan it obviously wouldn't be
China, ignoring the fact that 'China Syndrom' is just a buzz-word, not scientific fact)

That's the generally agreed definition, although none of the International nuclear bodies have a strict definition of the term .
You can read more on Al Gores internet-tubes, that is if you want to sound like you actually know anything about the subject .

RE: *Partial* meltdown
By slickr on 5/14/11, Rating: 0
RE: *Partial* meltdown
By drycrust3 on 5/14/2011 1:12:44 AM , Rating: 2
I think using the past tense and precising *partial* meltdown would make the article look a little more professional.

Agreed. But to be fair to Tiffany, the choice of headline may not have been her choice, that may have been decided by someone else.

RE: *Partial* meltdown
By wysiwyg009 on 5/14/2011 1:34:36 AM , Rating: 1
Someone else whose first name might or might not start with a 'J' and might or might not end in an 'N'... Seriously, Jason's articles are insanely sensationalist...

RE: *Partial* meltdown
By Etsp on 5/14/2011 5:01:23 PM , Rating: 1
Who's Jason Nick?

In any case, Jason tends to apply a pro-nuclear slant to his articles, while Tiffany applies an anti-nuclear slant to hers.

...Anyone know of a good news site that basically says: 'This is the FUD that CNN is spreading, and this is why it's FUD; Here's the FUD that Fox News is spreading, and this is why it's FUD. Here's what is happening without all the sensationalism' ? You'd think given that there is a void of non-biased news sources, that SOMEONE could make that sort of thing popular... :(

RE: *Partial* meltdown
By drycrust3 on 5/14/2011 8:27:20 PM , Rating: 2
Someone else whose first name might or might not start with a 'J' ...

I hope Jason won't be offended by this, but I don't think the person that decided this heading. It doesn't strike me as being his style.

By mkrech on 5/13/11, Rating: 0
RE: Yay!!
By Lanister on 5/13/2011 6:16:10 PM , Rating: 2
yes, too soon. IMHO a good guideline is if people are still suffering due to a disaster then it's too soon to make light of.

RE: Yay!!
By ppardee on 5/13/2011 7:13:17 PM , Rating: 2
So, with a half-life of uranium at 4.47 billion years, we have roughly 13 billion years to wait before we can make jokes?

Or maybe we can start in 150 years when the Cs-137 decays to acceptable levels?

Or we can just grow more seaweed. It seems pretty good at sucking up the bad stuff. Almost like nature has a way of neutralizing bad things in the environment...

RE: Yay!!
By Ushio01 on 5/13/2011 7:41:53 PM , Rating: 1
Or maybe we can start in 150 years when the Cs-137 decays to acceptable levels?

You mean 70 days.

RE: Yay!!
By PaterPelligrino on 5/13/2011 8:21:07 PM , Rating: 2
The phrase "decays to acceptable levels" is vague enough to offer a lot of wriggle room, and I'm not sure what the answer to that is; however, the half-life of Cesium-137 is 30 years.

It is the biological half-life of Cesium-137 that is 70 days, meaning that 70 days after ingestion , it loses half of it's radioactive toxicity through elimination, etc.

The Cesium-137 released by the Chernobyl meltdown 20 years ago is still a threat to human health.

RE: Yay!!
By randomly on 5/13/2011 8:30:50 PM , Rating: 3
Cs-137 has a 30 year half life. In 150 years 97% will have decayed away.

Almost none of it will have decayed in 70 days.

You may be thinking of the iodine-131 which has an 8 day half life. Only 1 part in a thousand will be left after 80 days, in 160 days only 1 millionth of the I-131 will be left, including whatever was in the seaweed.

Although the CS-137 lasts much longer, the iodine is more of a concern because of how strongly the body absorbs and concentrates it in the thyroid. CS-137 is thousands of times less hazardous because it's not readily absorbed or concentrated in tissues to the degree that iodine is.

Fortunately there will be almost no radioactive iodine left in a few months. Only about 1/200th of the original I-131 is left currently.

on the other hand your comment about 70 days is also partly valid since radiation levels for almost all areas except the plant itself are already fairly low.

RE: Yay!!
By drewsup on 5/15/11, Rating: 0
RE: Yay!!
By Solandri on 5/13/2011 8:49:32 PM , Rating: 5
So, with a half-life of uranium at 4.47 billion years, we have roughly 13 billion years to wait before we can make jokes?

This is a common misconception among people who don't really understand radioactivity.

Stuff with a really long half-life (thousands of years or longer) is relatively safe. Yes they're radioactive, but the long half-life means it emits the radiation so slowly that your exposure from handling it even for days is limited.

Stuff with a really short half-life (a few seconds to a few months) is also relatively safe. Put it behind some shielding and wait a while, and most of it has decayed into something else which emits no radiation or a lot less radiation. If you get exposed to it when it's fresh, then you have problems. But it only stays fresh for a short period. This stuff was why radiation levels were so much higher right next to the reactors than in the surrounding area. By the time these substances got carried by the air to the surroundings, enough time had passed that they'd decayed into harmless or relatively harmless substances.

It's the stuff with intermediate half-life which is dangerous. It's not short enough to become safe relatively quickly, and it's not long enough that the decay happens slowly enough to make it safe to handle. Stuff with half-lives of a few years to a hundred years or so falls into this category.

Iodine-131 has a half-life of 8 days. So for the first few weeks it's dangerous. After that, the remaining amount is so small that it's safe. Its decay product is stable Xenon-131.

Cesium-137 is a real problem. It has a half-life of 30 years. It's a beta emitter, but decays into a form of Barium-137 which gamma decays almost immediately. The worst of both worlds - a long half-life with a double decay emission.

For this reason, Cesium-137 and Strontium-90 are the primary radioactive byproducts of concern from a nuclear accident. Due to the nature of the accident, there wasn't a lot of Strontium-90 (29-year half-life) released as was in Chernobyl. That stuff builds up in your bones, contaminating you for life if you're exposed.

RE: Yay!!
By Angstromm on 5/14/2011 3:36:14 AM , Rating: 3
yes, too soon. IMHO a good guideline is if people are still suffering due to a disaster then it's too soon to make light of.

While I appreciate the sensitivity and compassion this response suggests, I want to add that humor is sometimes profoundly cathartic. Context is, I suppose, import as well. All I can say is, I so appreciated those friends who joked with me, and with whom I could joke, when my wife died in the Cedar Fire (in SoCal, '03). Laughter in the midst of profound heartache was, for me, a gift and helped me trust that I could go anywhere or say/share anything with those friends/family who could joke or get my jokes, despite the horrific circumstances.

RE: Yay!!
By SunTzu on 5/15/2011 12:44:47 PM , Rating: 2
I doubt the jokes revolved around how nice your wife smelled while being barbequed though, which is kind of what this could be seen as.

I think you should be able to joke about anything, but i wouldnt tell a joke about how fun radiation poisoning is to someone who's hair was currently falling out :P

RE: Yay!!
By Angstromm on 5/15/2011 2:21:52 PM , Rating: 2
I do tend to agree with you--as I said, context plays a part. If you know someone well, jokes, for instance, about my wife smelling like a barbeque could very well have their place (and there were jokes of a similar nature, so yr wrong on that account).

For me, I wouldn't be inclined to put a limit or cap on the sorts of jokes that my close friends say to me or that I might say to them under terrible circumstances. But then we love and understand one another well. Telling such jokes to a stranger could have disastrous effects. Depends. Again, circumstances and context. Sometimes going there--telling that "sick" joke--is exactly the right things to do. Sometimes one blows it and steps over the line. I never experienced that w/ my friends/family after my wife died.

As a side note, I work as a therapist/counselor with cancer patients and their families. Sometimes the joking gets pretty intense, but in my years of doing this work, I've never had a client tell me that we/I went over the line. Most express relief and appreciation for having room to "go there." Mind you, I'm not saying that I joke w/ all my clients or that they all joke w/ me. Some don't go there at all and I wouldn't dream of joking w/ some clients. Again, context.

Bottom line for me is: humor can be a very powerful tool for helping each other process the unimaginable. It sometimes allows us to say the unsayable. Sometimes it helps us to re-see the situation or experience it from a different perspective. Sometimes it allows us to say what we all know everyone is thinking but are afraid to say. Humor can be a way into the most tender, vulnerable and painful parts of human experience and therefor profoundly cathartic.

I'm not saying it's always right/apropos or always effective. But for me, in my life, there's always room for humor, having friends poke at my faults, stupidity, arrogance, whatever. I utterly delight in this sort of thing and am grateful I have those around me that care enough and are perceptive enough to call me on my shit in ways that also help me laugh at myself. Pretty powerful. But I don't assume that others are like me and want the same from me (theme of context, again).

RE: Yay!!
By tng on 5/16/2011 7:58:41 AM , Rating: 2
Well to be truthful, the first thing I thought of when they said that the reactor was leaking radioactive water into the Pacific was "Oh Crap", followed closely by "Isn't that how the lizard that became Godzilla was mutated?".

It is funny when something like this syncs up to a 50 year old cartoon, even in the face of profound tragedy. Not sure if I could really like or even get along with someone who could not laugh at the humor in a situation like this. Life it to short....

RE: Yay!!
By Belard on 5/13/11, Rating: 0
RE: Yay!!
By Integral9 on 5/16/2011 9:15:54 AM , Rating: 2
So with that in mind:

Oh nooooos.... it's Seaweed Thing and it's friend, Sumo Clam with it's Pearl of Power.. we must leave now.

You don't say
By bug77 on 5/13/2011 7:03:13 PM , Rating: 1
In 22 samples of seaweed, ten contained five times the legal limit of iodine 131 and 20 times of caesium 137. This is an issue for several reasons, including the fact that the Japanese household consumes almost 7 lbs of seaweed annually

Care to check for how long radioactive iodine and caesium are dangerous? Hint: at most a couple of months.

Yes, this could be an issue if ingested, but I just don't imagine Japanese fishermen scrambling for seaweed anywhere near the Fukushima power plant.

RE: You don't say
By icanhascpu on 5/13/2011 7:30:27 PM , Rating: 5
Its typical alarmist 'journalism'.

Make a scary title to shock people into reading, then provide big numbers like "20 times the legal limit!11" without providing actual information on what that actually means.

RE: You don't say
By Solandri on 5/13/2011 8:34:01 PM , Rating: 2
Cesium-137 has a half life of just over 30 years.

I would still say it's not as serious a problem as Greenpeace is making it out to be, because unless the dispersal pattern is highly unusual, you can just quarantine the area and prohibit seaweed harvesting from the area. Or just harvest it and bury it in a concrete coffin. Cesium levels outside the area should be safe (i.e. lower than what you get from exposure to natural radiation sources, like granite, bananas, and chocolate).

It's a nasty substance to deal with in concentrated form though - its widespread use in chemotherapy has led to a handful of nuclear accidents (non-reactor).

By semo on 5/15/2011 4:59:02 AM , Rating: 2
On March 11, 2011, a 9.0-magnitude earthquake struck Japan, resulting in the disabling of reactor cooling systems
I thought that it was the tsunami water flooding the backup generators that disabled the cooling system.

RE: incorrect?
By SunTzu on 5/15/2011 12:45:54 PM , Rating: 2
No, the tsunami knocked out the backup generators, the earthquake knocked out the power, which lead to a loss of cooling.

RE: incorrect?
By semo on 5/15/2011 2:18:12 PM , Rating: 2
Well that's my point. There wouldn't be loss of cooling if the backup power generators weren't flooded.

The biggest problem they had initially was that there was no safe way of fixing the power supply without exposing workers to dangerous level of radiation.

If there was no tsunami, the backup generators would have provided enough power (probably) to cool the reactors which would have stopped radiation leaking and hampering efforts to bring the situation under control.

The point I'm trying to make is that the power station survived the earthquake, but not the tsunami. You can say that the earthquake caused the tsunami in the first place so it was the culprit ultimately.

Deja Vu?
By icanhascpu on 5/13/2011 7:23:31 PM , Rating: 2
I thought I read about this here about a month ago?

According to Greenpeace...
By shikigamild on 5/15/2011 2:50:51 AM , Rating: 2
According to Greenpeace is a useless statement, Greepeace doesn't care about the data or the evidence, they make their own data.

For example, the Chernobyl Forum report found nine children who died from thyroid cancer, in the estimated 9000 excess cancer deaths expected among the 600,000 with the highest levels of exposure.

Greenpeace, puts this figure at 200,000 or more.
For Greenpeace, anyone that happens to die from cancer after the accident in that region, has a direct link to the accident.

By Ammohunt on 5/16/2011 2:51:53 PM , Rating: 2
According to Greenpeace, "significant amounts" of radioactive material had slipped into the sea. In fact, illegal amounts of iodine and caesium were found in seaweed as far as 40 miles from the Fukushima Daiichi plant.

Hey greenpeace a-holes its called a "natural disaster" 20k+ people could give a rats ass about legal or illegal amounts of radioactivity not to mention most of the workers that went into the plant at the early stages have pretty much comitted suicide to gain control of the site.

Thanks for the continued updates
By wallijonn on 5/16/2011 6:53:07 PM , Rating: 2
If it was Tiffany that wrote the article, or copied from another source, then I'd like to thank her for the update. I have been watching the TV news since the accident and it seems as if there is no more reporting. Good thing PBS re-broadcasts NHK news, otherwise there would be no news coming out of Japan.

So, when are you guys leaving for Japan ?
By Peter898 on 5/14/11, Rating: 0
RE: So, when are you guys leaving for Japan ?
By TimboG on 5/15/2011 6:02:24 PM , Rating: 1
I have to agree. Everyone talks about how it won't be dangerous very long but that is not the case. As stated earlier Bikini Atoll is a perfect example. Japan has a large part of it's diet based on seafood. Seafood which has been exposed to EXTREMLY high levels of radiation. This does not include the aquatic plant life which is also a large part of their diet.

It's easy to sit somewhere in a land-locked area eating beef and pork while making the statements that Japan will not be exposed to dangerous levels for an extended period of time.

With as dense a population as Japan has every square meter of ocean that has become radiated is now a threat to their health due to the type of diet.

I also agree that they make it seem "safe" with their postings of how fast the radition will go away but they say that while sitting at a PC thousands of miles away from the affected area. Think it's safe? Move your ass to Japan and eat seafood and kelp!

By smartalco on 5/15/2011 10:32:45 PM , Rating: 1
I'm specifically not moving to Japan for reasons that have absolutely nothing to do with radiation. Like not knowing Japanese, for one. There is also the whole 'my entire family is in the US' thing and the 'I don't have that much money' thing.

It is easy to sit at a computer and tell people to move to Japan while you sit there eating your chips.

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