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Full Version: 530 Sieverts per hour detected inside Reactor 2 at Fukushima Dai
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Quote:The iron scaffolding has a melting point of 1500 degrees, TEPCO said, explaining that there is a possibility the fuel debris has fallen onto it and burnt the hole. Such fuel debris have been discovered on equipment at the bottom of the pressure vessel just above the hole, it added.

TEPCO has played dumb for six years downplaying the disaster.  I'd say it was possible that the reactor core melted thru that grating like a hot knife cutting butter and it left behind some fuel debris for TEPCO to find.  When a reactor core leaves containment they call it fuel debris.  I'd call it a hundred ton corium blob.  

Hon, where's that nuclear fuel I had cooking in the kitchen?  Dunno, did you look in the basement?

TEPCO reports well readings between the reactor basements and the bay; for over a year now, always says Beta increases. They have decided that the Ocean is their dumping ground. No expensive, permanent underground barrier was built. No costly sea wall isolates the bay from the Ocean. The big money went to the Olympics.
Hey rad radio, great graphics.  It helps to imagine what it must be for a nuclear core to go AWOL.  The question in my mind is how deep into the basement it went.  As it eats thru concrete it gets bigger and slower, a la Chernobyl's elephant foot.  Water in the basement after the tsunami may have helped cool it as well.  I think this is what Tepco hopes for, that the melt hit water in the basement and formed a crust.  Keep pouring water on it; I heard 'em say.  It's difficult to read between the lines when TEPCO says so little so I watch what they're doing.  They continue to pour water into the holes and they pump up water from the basements and try to filter it.  The well rad readings are highest around r2 and r1.  I notice spark activity increases after earthquakes and wonder if the crust cracks or maybe foundation cracks change the water flow or levels.  In my layman's opinion sporadic fission is still occurring.  The folks at SimplyInfo have some good technical info and graphics for a better analysis.  TEPCO isn't releasing enough data for anyone to analyze so we can only guess.  

Your pic and insert might be close but I don't think the blob has melted very far under the basement.  Rain runoff, leaky tanks, and basement water seeping out to sea; not a problem for TEPCO because the sea is their dumping ground, it shouldn’t be legal and certainly isn’t good for the Ocean.  How'd you come to the idea of an old tube camera?  Makes sense to me, tubes and large components wouldn't fry as fast as transistors do.  BTW your signature Earth, Wind, & Fire - great band, great music, saw them in concert back in the day, fantastic live shows. Peace.  Thanks for joining in.
Hat tip Razzz at ENEnews

February 4, 2017 at 1:26 am · Reply
Here's an article with slightly better explanations and pictures. The hole in grating shown in the composite is 6 1/2 feet, more like a crater. A picture of the muon tomography for Unit 2 along with a drawing showing where a working core should be, looks to me like more than half the melt fell from the reactor vessel.

A quote from the article, “Unshielded spent nuclear fuel can produce over 1 million Rem per hour on contact (10000 Sv) the year after its removed from the reactor."

Not that it matters, technically, working core fuel rods are not as radioactive as spent fuel rods.

'Fukushima’s Reactor #2 is far more radioactive than previously realized'


I'm Not Here  • an hour ago  

The 3 melted reactor cores lost and have no containment. But no problem. TEPCO can't even guess correctly. They knew there was a hole in the bottom of Unit 2's reactor vessel because it failed and dumped an unknown amount of melt into the primary shell vessel. In this case it melted a hole through the grating and traveled below to the concrete floor that somewhat protects the metal shell bottom that is embedded in that concrete.floor

The first TEPCO thought was to just flood and fill up the primary vessel shell to submerge the reactor in the middle with water to shield any radioactivity emitting from the reactor core melt(s) (like they do fuel rods in spent fuel pools), to bad the primary vessel shell leaks like a sieve hence this is no containment. All the melts vent freely into the environment either via air and/or into groundwater leading to the Pacific Ocean.

No problem, TEPCO can measure it, observe it, think about it, charge ratepayers for it but nothing humanly possible can be done about it. Emptying the remaining damaged spent fuel pools is a major task that are still threaten by quakes and more dangerous than the melted cores if radioactive poisons contained inside those spent fuel rods ever escapes. IOW, spent fuel rods contain more radioactive poisons than working reactor core fuel rods.

Good pics and graphics at the extremetech link.  Though I might have oversimplified, I agree with I'm Not Here's more technical assessment in the comments. Did it go thru the metal shell bottom embedded in that concrete floor or outside the shell to the concrete floor? If so, that part of the blob is getting big and slow and will be further impeded when it hits saturated ground.  That's why I say it can't be very far under the basement.  The parts left behind up in the pressure vessel will be more concentrated fuel melts with developed crusts from water shielding.  The quake damage, salt-water and high radiation has weakened surrounding structure threatening collapses.  The core melts are bad news and they can't do much about it.  The leaks continue and they couldn't even isolate the basements from the underground water flow with a permanent physical barrier opting instead for the cheaper ineffective ice wall.  Removing the spent fuel is imperative before the building crumbles or shakes apart.  Yet the easier, less radioactive reactor 3 spent fuel removal has been delayed to add additional shielding.  Is it slowly dawning on TEPCO that the next unforeseen problem could be the show-stopper.
Hi Folks,,

SimplyInfo has more on the 530 Sievert/hr reading,,,

worse and worse,,

>>>The cause of confusion appears to be the translation of initial reporting from Kyodo News, also published at Japan Times. The headline calls it “the highest radiation reading since 3-11”. This new reading is the highest of the handful of readings taken in high radiation areas between 2012 and 2017, nothing more. It does not denote an increase of any kind. The confusing quote from Japan Times below:
“The radiation level in the containment vessel of reactor 2 at the crippled Fukushima No. 1 power plant has reached a maximum of 530 sieverts per hour, the highest since the triple core meltdown in March 2011, Tokyo Electric Power Co. Holdings Inc. said. Tepco said on Thursday that the blazing radiation reading was taken near the entrance to the space just below the pressure vessel, which contains the reactor core. The high figure indicates that some of the melted fuel that escaped the pressure vessel is nearby.”
This first sentence is extremely misleading in a number of ways. “Has reached a maximum” has given some readers an assumption that this reading is higher than previous readings for this location. That is not true. This is the first reading ever taken in the pedestal under the reactor vessel of unit 2. You have to have previous readings to claim this one is higher than previous readings. Since there are no previous readings there is no way to claim this is some form of an increase, a “spike” in radiation or in some way higher than before. This also would not be the highest reading since the meltdowns. Higher readings obviously took place, without some method of comprehensive recording there is no data of that to compare the new reading to. Ambiguous wordings seem to have led to a game of telephone where this morphed into rumors of a new problem at the plant.
Radiation levels in the pedestal during the meltdowns and subsequent weeks after would have been considerably higher. This 530 sieverts/hr reading is actually much lower than we expected to be found in the pedestal region, even this long after the initial meltdown. Our 2012 calculation of radiation levels inside the pedestal area where this 530 sievert/hr reading was estimated this week, was 5 gigasieverts/hr in 2012.


I have been reading and following along,,,, I am just so damn busy with all the projects I work on, I am usually overwhelmed with work. I think I may drop some other work, and come back more full time, because,, everything else I work on isn't going to matter if this plant goes full on ELE.
(02-04-2017, 10:23 AM)piajensen Wrote: [ -> ]"They've waited far too late to do anything about it" 

You call it correct, I do believe. Though, the fires seen onsite in some of the webcams caused me to think re-criticality. Though, I'm no physicist. Good time for them to embrace outside help to... wait for it -

Do something else entirely. 

Protect the Pacific from Fukushima. I've run this by in a couple forums before a few times, it never gains traction.

Build a Norwegian styled, massive seawall outside the port to "contain" (somewhat?) the leaks. Construct a dry land area inside that seawall upon which huge biological remediation is employed. 

Continuing to allow TEPCO to dump into the ocean is entirely the wrong thing to do. 

This is a good article about the geology of Fukushima. Report produced in 2011.

There is a fault under fuku, and the water will take that route.
The 530 sievert dose isn’t a direct measurement, it’s an analysis based on how much distortion was visible over a remote camera feed during the investigation this week.

Not surprising that the 530 Sievert dose came in lower than expected.  TEPCO has calculated the dose for us.  Just noting that TEPCO used a camera to determine radiation levels, lends weight to my using the tepcams for a rough estimate of the radiation clouds over the plant.  

How deep does the corium hole go?  How bout tossing a TEPCO exec down the hole and time how long before the screaming ends.  Whether the corium is shallow or deep; the contamination will spread to the Ocean.  

Thanks all for the contributions  Cool
(02-04-2017, 01:22 PM)piajensen Wrote: [ -> ]Wonder if any rad detection and camera techies are working on a new way to measure radiation....

Japan is the leader in camera technology. They have reason to develop better detection tools.
(02-04-2017, 11:02 AM)piajensen Wrote: [ -> ]Thanks for the article, it's very scientifically detailed. Not only a fault underneath the plant, but:

Permeability of the layers
Andreas Küppers, a German geologist who had intervened on the site during the construction of the plant, was interviewed in March 2011 by the newspaper Die Welt. According to this specialist from the GeoSearch Center Potsdam (GFZ Deutsches GeoForschungsZentrum), the different layers of argillite on which the plant is built are likely to be waterproof and should be able to prevent contact with groundwater (2). But this opinion is not shared by everyone. One dissenting Japanese geologist, for example,  - who wishes to remain anonymous -  has been noted for his views expressed on a U.S. forum, "Physics Forum": according to him, the bedrock of the region is made of coarse, very permeable sandstones, and contains vast amounts of water from the neighboring Abukuma mountain. This groundwater, he claims, is flowing under the plain towards the sea at a very low speed of about 50 cm / day (3).
In fact, in light of the collected data, it seems that the views of these two geologists may not be conflicting after all, because both types of layers do exist: argillite (or silt) and sandstone. However, Andreas Küppers, in line with Tepco's style of communicating, refrains from disclosing all the information he possesses: namely, that there is not only waterproof argillite, there are also some strata of permeable sandstone, which allows groundwater to move towards the sea. Moreover, the presence of this fault under the plant makes it possible for the water to sink down vertically without being stopped by a horizontal waterproof layer of argillite, and allows connection between several sheets of groundwater which one would have thought were independent."

So, if we could turn back the hands of time... knowing what we know now - that site should never have been chosen for a nuke plant.
Very welcome PIa.

It's a very good article I go back to it often over the years. I have shared it with many people.

 Yeah there are so many issues with the ground that plant is built on. They also changed the course of the river that used to run through that area.

Is why a sarcophagus like Chernobyl has will not work with Fuku. There is much to much water flowing on, around and UNDER the plant, and it all is flowing into the Pacific.

So many problems, even the exhaust towers are collapsing.


(02-03-2017, 06:15 PM)rad radio Wrote: [ -> ]I was looking at that video and realized it's a old fashioned tube camera which is the only imager that can withstand that much radiation.

Also notice the continuous rain of water which ultimately is going out to sea, along with the steam coming off it.

Quote:hundred ton corium blob

Here's one person's rendition of some of the corium :

Here's another :

And here's mine (I included an earlier illustration I made before, when the disaster began, as an insert)

Great work on those graphics!!   Here is a interesting link about corium experiments done at Argonne,,

your images reminded me of this site.

Was looking for a link to a German study on nuclear meltdowns with info on why meltdowns increase in radioactivity and of course can't find it now.  Anyone with a link?

edit - found the pdf and got a link to the study.
Dispersion of radionuclides and radiation exposure after leaching by groundwater of a solidified core-concrete melt
added for reference.

Did stumble on these while looking.  Adding these for reference.  

The Geology of Fukushima

The Geology of Fukushima. Porous ground, lowered 10 metres, built over an aquifer with a fault line present, with basements below sea level


An interesting hypothesis, includes more links -
TEPCO cooked Core of Reactor 2 and then blew it out
Right you are Rad Radio.  Neutron activated products pose new hazards to the biosphere.  Neutron embrittlement and salt corrosion is further degrading the 40 year old reactor.  One thing we haven't discussed was just how much of reactor two was ready to collapse.  When first reading the news articles I got the impression that only a small square meter section was in danger of immanent collapse that could block their ingress.  Does TEPCO really think those buildings will stand for another 40 to 300 years?  They admit to not being able to do much about the melted cores so what do they do to stop the spread of contamination?  

From the German study; suggested technical measures to limit the spreading of radioactivity.

Installing impermeable walls around the plant.
Pumping off the groundwater in order to dry the reactor foundation.
Installing extraction pumps to prevent groundwater from leaving the site.
Making special use of soil freeze techniques.

The impermeable wall wasn’t built – maybe too expensive or technically difficult for the site.  Pumping groundwater but it can’t dry the foundation because of the underground river inflow that wasn’t blocked.  Extraction pumps to filter the dirty daughters and store the tritium water in tanks for later release to the sea.  The soil freeze techniques were not very successful.  

TEPCO's half-baked response actions indicate they intend to let as much contamination as possible flow downwind and downstream.  Parts of Japan got as contaminated as Ukraine and TEPCO doesn't want further concentration to make the site unworkable when they can share the pain with the rest of the world instead.
I admire Iori Mochizuki for evacuating and speaking out with Fukushima Dairy because politics has governments playing with peoples lives.  Don't be part of an unplanned experiment with your health.  Seek out less contaminated areas to live in and grow food in.  Get the overgrown babies out of leadership positions and find some adults who care about more than just themselves.  Quit playing nuclear roulette and phase out nuclear power for safer power sources.  Three meltdowns leaching into the sea and chances of another spent fuel pool fire filling the air could mean a short future for all of us.  

Here's one of the meltdowns, pics before and after a nuclear lava flow melted thru containment to become a corium blob hiding in the basement.  
Fukushima Unit 2 Failure Point Found!
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