Tokyo Electric Says Fukushima Fuel Rods Damaged, Leak to Sea

http://www.businessweek.com/news/2011-03-21/tokyo-electric-says-fukushima-fuel-rods-damaged-leak-to-sea.html

March 22 (Bloomberg) -- Tokyo Electric Power Co. said fuel rods at its Fukushima Dai-Ichi power plant have been damaged, releasing five kinds of radioactive material and contaminating seawater nearby.

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The disclosures on the spread of radiation were made in a press briefing after midnight Tokyo time and in a press release this morning.

Iodine-131 was detected at 127 times normal levels from sample water taken at 2:30 p.m. yesterday, while cesium-134 levels were 25 times normal and cesium-137 was at 17 times normal, Tepco said on its website.

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edit: reports differ on where these sample were taken - either 100 m or 100 km from the plant

Into the sea.

Some of the elements that have been detected are fission products. You aren't going to get them by running water through a leaky fuel pool... it has to go through the core of a reactor that was recently running.

So it's (mostly) from the steam releases that they were forced to make when they couldn't cool the reactors... which means that it was much higher a few days ago... they just weren't checking it.

Or maybe, like some nuke plants here, they just discharged waste water into the sea.

TEPCO has not told anyone what they have been doing with the seawater used to cool the damaged cores and no one is sampling the atmospheric plume over the ocean - or the waters impacted by the plume.

I suspect there is much wider contamination of Japanese coastal waters than anyone wants to admit.

yup

n/t

That's really the most likely primary source. The winds were mostly offshore at the time. There shouldn't be any surprise that if there's contamination miles away on land... there's going to be lots more in the water right next to the plants.

away.

Radioactive particles don't just disappear until they decay.

where benthic organisms canr emobilize them back to the water column - or accumulate them in cells/tissues and pass them up the fisheries food web.

There's a lot we do not know about the fate of the radioactive material released from that plant into Japanese coastal waters.

Some needs to do a CTD grid of the water column and take some sediment cores...and maybe deploy some drifters at the plant outfall to track currents dispersing that stuff.

yup

Like they did after Macondo... I wouldn't hold my breath.

and they published a lot of that data - in Science - as events were still unfolding.

Unfortunately, I do not think the Japanese will respond the same way.

and information will just dribble out in the most obscure manner possible

yup

Data-collection problems notwithstanding.

They are the foundation for the food chain in the oceans, and much of the organisms that consume it get eaten by something larger and so on up the ladder, concentrating the effects as it goes up. Ocean currents are as much of a concern as the jetstream. Sea life tends to migrate, too. It's not like all the fish just hang around in one place. What a mess.

However, the risk of consuming seafood is manageable. Right now the location with high levels is known and the food can be avoided fairly easily. As time goes on the risk will be reduced by the dispersal of the particles into the enormous volume of the ocean. Some residual elevate risk will remain, in theory, but after 10 years it will be impossible to distinguish from the background variability.

It might be the case that the highest risk will come in a year or so, when the particles have spread out far enough not to be trackable but not so far as to be down in the environmental noise.

indicated that whale meat from protected whale species was being sold there.

I don't trust their ability to police fish markets for contaminated fish.

and the notion that currents will simply disperse those materials to low concentrations does not take into account the biogeochmistry of those isotopes

yup

I-131 has a half life of 8 days.

After 30 days less than 7% remains.
After 60 days less than 1% remains.
After one year less than one part per trillion remains.

> reports differ on where these sample were taken - either 100 m or 100 km from the plant

:P

As a serious comment though: thanks for the updates - and the honesty to point
out the failings in them too!

:toast:

http://www.csmonitor.com/World/Asia-Pacific/2011/0322/Japan-says-high-seawater-radiation-levels-are-no-cause-for-alarm

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Plant operator Tokyo Electric Power Company (TEPCO) announced today that in samples taken 1,100 feet south of the plant on Monday, radioactive iodine exceeded legal limits for wastewater by 126.7 times, cesium-134 by 24.8 times, and cesium-137 by 16.5 times. Samples taken 16 kilometers (10 miles) south were up to 16 times above legal levels.

Radioactive elements in the ocean will not likely pose a threat to human health because they quickly become diluted, says Masaharu Hoshi, a specialist in environmental impact assessments at Hiroshima University’s Research Institute for Radiation Biology and Medicine. He says contamination of seawater was not a problem following the atomic bombing of Hiroshima and Nagasak.

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Cs-137 is the only real concern there.

With short halflife unless someone plans on drinking seawater in the next couple days the risk is minimal. Even if the I-131 is consumed by sealife it will decay rapidly.

After a month only 13% of I-131 will remain.
After two months only <1% of I-131 will remain.
After three months only 1/2000th of the I-131 will remain.

Combined with the effects of dilution even detection will be difficult.