Fukushima radiation higher than first estimated, TEPCO admits

By Kevin Krolicki

National May. 25, 2012 - 11:00AM JST ( 27 )

TOKYO —

The radiation released in the first days of the Fukushima nuclear disaster was almost 2-1/2 times the amount first estimated by Japanese safety regulators, the operator of the crippled plant said in a report released on Thursday.

Tokyo Electric Power said its own analysis conducted over the past year put the amount of radiation released in the first three weeks of the accident at about one-sixth the radiation released during the 1986 Chernobyl disaster.

“If this information had been available at the time, we could have used it in planning evacuations,” TEPCO spokesman Junichi Matsumoto told a news conference.

Because radiation sensors closest to the plant were knocked out by the March 11, 2011 quake and the tsunami, the utility based its estimate on other monitoring posts and data collected by Japanese government agencies.

TEPCO, set to be nationalized in July in exchange for a Japanese government bailout, estimated meltdowns at three Fukushima reactors released about 900,000 terabecquerels of radioactive substances into the air during March.

That was 2-1/2 times the amount of the first estimate by Japan’s Nuclear and Industrial Safety Agency in April last year and about 17 percent more than the highest estimate provided by the government safety agency.

The estimate was based on measurements suggesting the amount of Iodine-131 released by the nuclear accident was three times higher than previous estimates, the utility said in the report.

Iodine-131 is a fast-decaying radioactive substance produced by fission that takes place inside a nuclear reactor. It has a half-life of eight days.

More than 99% of the radiation released by the accident came in the first three weeks, it added.

The Fukushima Daiichi plant, which had six reactors, was hit by a series of hydrogen explosions and meltdowns after power and cooling systems were cut off by the tsunami.

The World Health Organization released its own study this week concluding that residents around the Fukushima plant had been exposed to up to 20 times normal background radiation in the first year after the accident. That was still within the WHO’s recommended emergency limit.

Officials expect it will take up to 30 years to decommission the Fukushima reactors. The accident has prompted a debate over the future of nuclear power in the resource-poor nation.

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27 Comments

9

yokattaMay. 25, 2012 - 07:48AM JST

Old news. Everybody knows this stuff! TEPCO lied and continues to - period!
4

JT1023May. 25, 2012 - 07:52AM JST

We all knew this just based in our gut feeling of the situation. I am happy that they are passing along information even if it's to little to late. The truth will always come out in time!
0

marcelitoMay. 25, 2012 - 08:14AM JST

No surprises
-2

TheBigPictureMay. 25, 2012 - 08:17AM JST

Maybe it was seven times more, or a hundred, because nuclear industries and governments say what they want. Or, in the case of the U.S, say nothing at all.
0

ShermanMay. 25, 2012 - 08:17AM JST

Is this news?
3

zichiMay. 25, 2012 - 08:21AM JST

Last year, TEPCO first stated the radiation released was 750,000 terabecquaerels but some months later revised that down to 350,000 terabecquerels. That was during the time of ex PM Kan who insisted all info released from TEPCO was agreed by the nuclear disaster info office.

Now TEPCO has again updated the radiation level to 900,000 terabecquerels, but also stated this was the total amount since 3/11 so I'm unclear on this.

The total radiation released at Chernobyl is 5 million terabecquerels but I don't know the amount released in the initial disaster period?

Officials expect it will take up to 30 years to decommsion the plant.

It could also take much longer than that. Last year in Britain, a nuclear plant was closed and the gov't stated it would take 90 years to decommssion.

The estimates for the cost of the nuclear disaster range from ¥25 trillion to ¥45 trillion plus. The more decades it take the higher the eventual price will increase.

Japan needs to resolve the problem of nuclear waste storage.
2

OMGhontoniMay. 25, 2012 - 08:26AM JST

"So we got it wrong, but only because we were wrong about the Iodine-131. It was 3 times higher than estimated but not to worry because it only has a half-life of 8 days."

Oh please. More than a year on and still trying to downplay the reality. If you were wrong about the Iodine, chances are you were also wrong about other far nastier isotopes too, and just how has this "information" suddenly come to light, if you didnt have the means to gather the data in the first place? Is it really 2 1/2 times more, or 10 1/2 times more? We will never know, will we?

Not trying to scaremonger, just want to know the truth. Still dont think this is it. But then, I dont think any of us would know the truth even if it did jump up and bite us now - TEPCO have blown any chance of us ever believing anything they say.
3

DisillusionedMay. 25, 2012 - 08:35AM JST

But, before we go damning TEPCO. for their deception let's not forget the J-Gov was adiment for nearly two weeks after the quake that there was no meltdown at all. While it may only be the second largest nuclear disaster ever, it is still holding the trophy for the biggest load of BS ever released to the public.
2

hoserfellaMay. 25, 2012 - 08:39AM JST

Lies wrapped up in more lies. It's the Japanese way. Anyone who wants them to sit down at the UN Security Counsel big table with the adults should look at the NK-like secrecy and utter incompetence from the Fukushima mess.
3

gaijinTechieMay. 25, 2012 - 08:51AM JST

They will deny admitting it later. They've done it before, got away with it, so they'll do it again.
2

Ted BarreraMay. 25, 2012 - 08:58AM JST

Wish the article mentioned how much cesium, strontium, and plutonium was released according to the new estimate. Iodine-131 with a half life of 8 days is the least of our worries compared to those bad boys.
2

smithinjapanMay. 25, 2012 - 09:18AM JST

I bet this still isn't even close to the truth of the extent of the damage, but since TEPCO is still very much under the gun they're only going to continue letting the truth trickle out as time elapses. We'll probably NEVER hear or now about just how bad things were and are, and certainly not until after the government has forced the reactors back on and can successfully say 'shouganai'.
2

Christina O'NeillMay. 25, 2012 - 09:33AM JST

so are they still frugal with the truth in relation to the contamination as it stands at present?
2

DebuchoMay. 25, 2012 - 09:34AM JST

I will never forget seeing the images of these buffoons dumping ocean water on exploded nuclear reactors and telling us not to worry because everything is safe. That was 5 days after the quake and it seems the only thing that has not changed is... they are still buffoons.
2

valued_customerMay. 25, 2012 - 09:37AM JST

Another layer added to the onion they know most people won't bother to peel.
1

gogogoMay. 25, 2012 - 09:39AM JST

You'll also more than likely find this in the low estimate.
1

Elbuda MexicanoMay. 25, 2012 - 09:43AM JST

Surprise?? News?? What a load of BS!
0

LilicMay. 25, 2012 - 09:47AM JST

Like everything else in this country is hidden !!!
-3

basroilMay. 25, 2012 - 09:55AM JST

Ted, if any plutonium was released, it would be in the milligram or microgram range, as that reactor core type does not produce plutonium and the MOX fuel on site never reached the critical heat level needed to disperse. As for Cs/Sr, only trace amounts would have been carried by the wind inland, most would have gone out to sea where it will disperse and be absorbed into the rocks at the bottom of the sea. Considering those rocks already have plenty of radioactive isotopes, the increase will not be measurable.

Another interesting fact is that neither those two nor I131 are particularly dangerous, in fact it's about the same as going outdoors without sunscreen. Beta emitters like those three and even Uranium have very low levels of gamma radiation, and the beta radiation is stopped by a simple aluminum sheet or even a bit of water. Ingestion is about the only way that it can affect you (other than medical beta- ray sources, which are in the hundreds of mSv/hour range), and everyone from the government to private citizens have been monitoring that.

As for the jumps in radiation readings, you need to understand that the levels could only be measured inland since nobody was monitoring the sea (TEPCO normally did but come tsunami, go the sensors). Very likely if you read the full report you would find that almost all the increase is in the ocean level calculations. But considering they probably used pre-quake dispersion models, and many of the undersea currents have changed since then, we will probably see another revision (likely revised down again).

As for biggest BS, you people forget that Chernobyl wasn't even disclosed until well after the fires were put out, and by then a large section of the most fertile and populated land in the USSR was heavily contaminated due to an exposed core. It's not always about how much, rather how much it affects people and population centers. That's the reason why the Bikini Atoll blasts didn't have anywhere near as much effect as the Hiroshima bombing, even though that test was about a hundred times more powerful.
1

ExportExpertMay. 25, 2012 - 09:58AM JST

And why would any one believe this new figure they are saying? Little by little the real truth is unveiled, because they now state this or that still does not mean full disclosure, its just one more small step down the path to the real and whole truth. It maybe 20 or 50 years untill the full truth is uncovered or disclosed.
1

kurisupisuMay. 25, 2012 - 10:04AM JST

“If this information had been available at the time, we could have used it in planning evacuations,” TEPCO spokesman Junichi Matsumoto told a news conference.

Does Mr Matsumoto expect the public to believe that the staff at Fukushima didn't have access to to hand held dosimeters?

The conclusion is that people should have been evacuated but were not?
1

zichiMay. 25, 2012 - 10:09AM JST

TEPCO has estimated the total amount of radioactive substances emitted measured 760,000 terabecquerels, 1.6 times the estimate released by NISA in February.

It reached a final estimate of 400,000 terabecquerels of iodine-131 and 360,000 terabecquerels of cesium-137.

The amount of cesium 137 released at Chernobyl was 85,000 terabecquerels.

One terabecquerel is equal to 1 trillion becquerels.

http://www.yomiuri.co.jp/dy/national/T120523005514.htm
0

Thomas AndersonMay. 25, 2012 - 10:21AM JST

Everything is just fine, just fine... don't panic everything is all right there's nothing wrong.
1

SquidBertMay. 25, 2012 - 10:24AM JST

the MOX fuel on site never reached the critical heat level needed to disperse.

Do you have a source for this?

Lots of articles last fall mentioned plutonium being found far(40km) from the reactors. http://www.ft.com/cms/s/0/7e3af460-ece6-11e0-be97-00144feab49a.html

Another interesting fact is that neither those two nor I131 are particularly dangerous, in fact it's about the same as going outdoors without sunscreen. Beta emitters like those three and even Uranium have very low levels of gamma radiation, and the beta radiation is stopped by a simple aluminum sheet or even a bit of water. Ingestion is about the only way that it can affect you.

I don't think anyone ever said anything else than that Ingestion and Inhalation are the main dangers for areas further away from the reactor. You are however very incorrect in stating that those isotopes are not particularly dangerous. I am not one of those saying that we are all going to die, but the isotopes present a serious health risk depending on the dose. Not fully accepting this will only cause problems for the future.

The thing to understand here is that the unit used to measure the effective dose (Sv) already compensates for the difference between beta, alpha and gamma emitters by using different weighting factors for different types of radiation and different types of body tissue. Thus the effect of a dose of 1mSv is always the same independent of the radiation source. This is in contrast to gray (gy) which is simply one joule of ionizing energy absorbed per kilogram.
0

JaneMMay. 25, 2012 - 10:33AM JST

I do not justify what TEPCO or the government did, but during the first several days and even weeks, TEPCO did not have the means to confirm the meltdowns. Those who watched the news at the time probably remember that they used the expressions 確認できません、確認していません, meaning "we cannot confirm" and "we have not confirmed" There are many things which will become clear from now on and a lot of data will be released based on further observation and analysis.
1

DoLittleBeLateMay. 25, 2012 - 10:34AM JST

most would have gone out to sea where it will disperse and be absorbed into the rocks at the bottom of the sea

That's some serious willpower there, buddy.
0

SquidBertMay. 25, 2012 - 10:38AM JST

As for the jumps in radiation readings, you need to understand that the levels could only be measured inland since nobody was monitoring the sea (TEPCO normally did but come tsunami, go the sensors)

Also thought I should comment on this.

The USS Ronald Reagan (I think) was measuring the dose out at a distance of something like a 100 nautical miles.
From what I heard the numbers where kept from the public on request of the Japanese government.