Complete Chronological Analysis Of Fukushima Reactor 1 - 3 Data

Tyler Durden's picture

With TEPCO unwilling (or unable) to disclose consolidated detailed information about the status of its reactors, the task has fallen on third party analysts. Luckily, Jorge Stolfi of the state university of the State University of Campinas in Brazil, has compiled what is probably the most comprehensive data dump of all key Fukushima reactor indicators including water level, core, drywell and torus pressure, as well as temperature at the core bottom and nozzle. Below are the detailed results for each of the fuel loaded reactors since the start of the crisis.

Reactor 1

Reactor 2

Reactor 3

Further details on the legend and methodology:

Water level

This quantity is the water level inside the (inner) reactor
pressure vessel, in millimeters, measured from the top of the
fuel elements. Negative values mean that the fuel is partly out of
the water. The "B" reading is used in preference to "A".

Core pressure

This quantity is the absolute pressure in the inner reactor pressure
vessel, in kilopascals (kPa). The "B" reading is used in preference to "A" or "C".
Note that 101 kPa is approximately 1 bar (one atmosphere) i.e. the pressure inside
the core is the same as that of air outside the building.

Drywell pressure

This quantity is the absolute pressure (kPa) in the "drywell", the outer pear-shaped
steel container that surrounds the reactor. A value of 101 kPa means
the same as outside air pressure.

Torus pressure

This quantity is the absolute pressure (kPa) in the suppression container, the
torus (donut) shaped chamber below the drywell container. A value
of 101 kPa means the same as outside air pressure.

Core noz. temperature

This quantity is the temperature (Celsius) of the
reactor's (inner) pressure vessel, taken at the injection nozzles. Note:The
value is multiplied by 10 for clarity. The upper limit of the sensor's range
(400 C) was exceeded on some occasions.

Core bot. temperature

This quantity is the temperature (Celsius) at the bottom of the
reactor's (inner) pressure vessel. Note:The
value is multiplied by 10 for clarity. The upper limit of the sensor's range
(400 C) was exceeded on some occasions.

Data sources

The water level and pressure data through 2011-03-17 come from the
NIRS PDF document titled
of the plants of the unit 1-3 at FI site
', fetched from
the Nuclear
Information and Resource Service
site on 2011-03-22. That site

Here is a document on the condition of Units 1, 2 & 3 from March 13-17,
showing water levels and containment pressure, obtained through Citizens'
Nuclear Information Center in Tokyo.

Core pressures in that document were relative to atmospheric
pressure, so they were incremented by 101 kPa to match the
other pressures (all absolute).

Data from 2011-03-22 onwards comes from the Nuclear and Industrial
Safety Agency (NISA) News Releases.

The temperature readings from 2011-03-19 06:30 to 2011-03-22 15:30 were obtained from
a scanned
presumably prepared by TEPCO. After 2011-03-22 the data
weer taken from the NISA bulletins (see above).

Data from 2011-03-22 onwards (water level, pressure, and temperature) come
from the Nuclear and Industrial
Safety Agency (NISA) News Releases

For further information please contact the document authors.

Data files

The water level and pressure data was entered by hand into
a separate text file fo each reactor, namely data-un1.txt,
data-un1.txt, and data-un1.txt.
The emperature data was placed in separate text files heat-un1.txt,
heat-un1.txt, and heat-un1.txt.

Values that were missing in the original documents are encoded as
"99999" in these files. Entries that were marked "down scale" are encoded as "88888".
(It seems that many of these may be "over scale" instead.)
Missing and out-of-scale values appear as gaps in the plots.


The core pressure of reactor #1 on 2011-03-16 6:00 was given as
"0.62 MPa" in the NIRS table.
That must be a typo. I have corrected (hopefully) the value to "0.162 MPa".

A few other values in the original source documents sand so far out from
the neighbors (both before and after them) that they must be errors too.
However it is not clear which are the correct values:

  • Reactor #1, 2011-03-24, 11:00, the given temperature "175C" is too low. Perhaps "225C"?
  • Reactor #2, 2011-03-13, 9:55 and 10:35, the core pressures given
    as "1.283 MPa" and "1.263 MPa" are much lower than the previous value
    (6.08 MPa at 9:25) and the next one (5.85 MPa at 16:00).
    Interpolation of the smooth trend would give around 5.9--6.0 MPa.
    On the other hand, there seem to be sudden transient excursions in the
    drywell and torus pressures at that same time; so the data may be
    correct after all.
  • Reactor #2, 2011-03-16, 14:00, the drywell pressure is given as
    "400 kPA" in the NIRS table,
    dropping to 75 kPA at midnight.
    But NISA's
    News Release 26
    claims that the pressure had already dropped to "40 kPA" at
    12:25. perhaps the time of the NIRS table is incorrect: instead
    of 14:00 it should be 12:00?
  • Reactor #2, 2011-03-17, 11:25, the water level is given as
    "-1800 mm" in NISA's Release 28.
    That may be a typo; the correct value seems to be -1400 mm.
    Note that -1800 mm is the correct water level for reactor #1.
  • Reactor #3, 2011-03-20, 11:00, the water level in the core is
    given as "-2350 mm" in NISA's Release 36.
    That is a dip of 350 mm from the adjacent values. However the
    torus pressure at that time went off scale (greater than 400 kPa).
  • Reactor #3, 2011-03-20, 15:20, the presure in the suppression torus
    is given as "800 kPa, ~ down scale" in NISA's Release 37.
    However the previous report gave "400 kPa ~ over scale", so the
    two values may be guesses for some unknown value above 400 kPa.
    Indeed most readings between 2011-03-14 and 2011-03-24 are
    given as "down scale", but seem to be "over scale" instead.


h/t Jeroen

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George the baby crusher's picture

This makes me feel so much better about so many things.

The Limerick King's picture

This nuclear nightmare proceeds

Who knows where the fuck this will lead

While government lies

A great nation dies

The result of our hubris and greed.

AN0NYM0US's picture

and in other end of the world news

(Reuters) - Wal-Mart Stores Inc will re-open 12 of its Seiyu stores in Japan which were affected by the earthquake, and is hoping to open the remaining 12 impacted stores as soon as possible, a spokesman for the U.S.-based retailer said.

Wal-Mart has 371 stores and 43 deli outlets in Japan, of which 24 were affected by the March 11 earthquake and tsunami

falak pema's picture

Can I have a hard-on again without bringing Fukushima to melt down?

I hope Dr Stolfi has the answer...

jesus_quintana's picture

Asked in another thread, but might have a better chance of an answer here... Anybody know why the Fed hasn't released the discount window docs yet? (apart from the fact they're lying bastards who think they're above the law)

jballz's picture

They are not above the law, they are the law. Or above it if need be I guess, but seldom does the law need to rise above itself.

Have you ever noticed no federal reserve scandal has ever happened? Elected politicians, of course. All branches of everything. Private sector banks too, and all other branches of the power structure have scandals.

Not the fed though. No nannys without work visas, no hookers on video, no nada zilch. I have never seen anyone on the fed roster accused of a single impropriety.

You should all be grateful such a squeeky clean and law abiding collective of great minds has devoted themselves to money supply control.



jesus_quintana's picture

No disagreement from me chief, but that doesn't really answer the question. Anyone?

Bastiat's picture

Geithner came out of "Inside Job" a bit tainted on the making GS whole one its AIG CDS.

Mae Kadoodie's picture

Fed is probably holding back data dump waiting for the next big event to divert everyone's attention (hopefully for them this would occur on a Friday after market close).

Id fight Gandhi's picture

I'm sure all this data must mean something to someone. Just wish they'd fix the problem or get more help already.

Cognitive Dissonance's picture

This is no more "fixing" the problem. That opportunity was lost when each unit exploded. Now all there is left to do is stem the tide and try to mitigate the disaster. There is no fix, just mitigation. Period.

And I believe the ability to mitigate this disaster, meaning in this case the effort to diminish the effect and consequences of the disaster, has also passed. That point was passed when they began pouring seawater onto the buildings. It was admitted at the time that doing so was a Hail Mary pass, a last ditch effort. Now we are seeing the effects caused or aggravated by the Hail Mary pass, which was attempted because of the explosions, which were caused by spiking temperatures which were a symptom of a partial meltdown etc etc etc etc etc etc etc.

Does anyone else notice that they are at the point in this disaster where whatever they do has consequences elsewhere, effects that are sometimes unknown at the time. How many people think the water in the basement of these buildings was caused not just by the partial core meltdowns but pouring seawater, then spraying seawater, on the buildings?

They are rapidly painting themselves into radioactive corners and they know it. In fact the US and every other country in the world already knows it. This is why they are pulling their people out of Japan. Forget what people say. Watch what they do. At this point in the Three Mile Disaster there were long articles in the papers describing in detail efforts to date as well as efforts needed to control, then mitigate the disaster. Where are those articles today describing the Fukushima disaster?

Rats leaving the ship and a silent press spells trouble.

Stoploss's picture

Well put. For me, uncapped contractor day rates spell trouble in capitol letters.

TaxSlave's picture

How many people think the water in the basement of these buildings was caused not just by the partial core meltdowns but pouring seawater, then spraying seawater, on the buildings?

Since you asked, hasn't it been abundantly clear to everyone since this began that all the water they poured on the mess would pool at the lowest point?  It will, and has been running into the sea since apparently the buildings are busted up along with the piping. 

Rats leaving the ship and a silent press spells trouble.

It sure does.

Thorlyx's picture

 hasn't it been abundantly clear to everyone since this began that all the water they poured on the mess would pool at the lowest point? 


You might be on to something here. Many some smart nuclear engineers could help us here dertermine if this is eventually possible.


Just kidding !

TuffsNotEnuff's picture

The only people surprised at gravity are the press.

Also, 79 picoCuries/liter trace amount of iodine in Massachusetts rain water got 14,000+ blurbs so far.


These guys love paying $3.50 a gallon for gas instead of converting to electrics and saving at least $400-billion a year in foreign exchange by not importing oil ???


nkktwotwozero's picture

>hasn't it been abundantly clear to everyone since this began that all the water they poured on the mess would pool at the lowest point? 

Water? Like from the toilet?

Brawndo! It's got what Nuclear Plants crave!


westboundnup's picture

After Chernobyl, the USSR quickly constructed the sarcophagus for fear of the damage that would be done by rain.  Why do the Japanese not have the same fear?

Bubbles...bubbles everywhere's picture

Could it be because the japanese have another peculiar cultural trait which is that they don't care much about the rest of the world?  

nkktwotwozero's picture

>USSR quickly constructed

It took the Soviets 7 months to build.

UninterestedObserver's picture

"Radiation levels that can prove fatal were detected outside reactor buildings at Japan’s Fukushima Dai-Ichi plant for the first time, complicating efforts to contain the worst disaster since Chernobyl in 1986"


So does this mean TRAV was wrong?

Thorlyx's picture

possibly or probably temporarily partially.

Cognitive Dissonance's picture

By his own admission, Trav7777 said he is never wrong. This little gem speaks volumes about the type of personality we are dealing with here, someone who believes he is never wrong and would never allow himself to be wrong. Do you think he would ever admit to being wrong? Nope.


by trav7777
on Sun, 03/27/2011 - 12:15

Dude, how the fuck do you think I was ABLE to be first with that post unless the retraction was ALREADY OUT?

By the time TD put up the goddamned page to draw you flies in, the reading had ALREADY BEEN RETRACTED.  He knew it and I knew it. 

I understand the psych phenomenon of projection.  Consequently, I do understand how you people could believe I am talking shit, because you yourselves pretty constantly are.  Downing Effect.  READ it.  Write a fucking NOVEL on it.

But, anyone who has done even a paucity of psych analysis would realize straight away that being wrong publicly is an anathema to me, which is why I take great pains to never do it.

A fair recitation of the facts would have made equal emphasis to the retraction, instead of paragraphs of shit about the initial reading buttressed with utter CRAP about the radiation burns suffered in the water by those 2 workers, as if TEPCO EVER said the things TD just attributed to them.

DrRaolDuke's picture

So all reactors have at least part of rods still above water and over 7 feet of fuel rod still exposed in reactor 3?

fredquimby's picture

And is the reason I am not out dancing in the rain.

Along with this of course:

Jim in MN's picture

Yes, this has been consistently reported in the daily summaries, and has apparently just led to the startling conclusion that there is a hole in the bucket...s.

DrRaolDuke's picture

Agreed. Didn't realize that much was exposed in reactor 3 though. So Jim, couple questions for you: 

If we were to say that, without a doubt, there is at least ONE vessel breach, then we would be saying that fuel pellets have piled up in at least one drywell?

And if we say all this, then the rad levels they are reporting are much lower than they should be?


Jim in MN's picture

I am not there yet.  We have the pressure readings indicating a blowout, and the informal/quickly deleted NYTimes quote from a US source about a crack up the Unit 3 reactor vessel.  Neither by itself necessarily means that fuel has exited a core in any quantity.  Everything we observe could be explained by cores that are damaged but held, suspended as it were, in the reactor vessels.  Cladding material has even been detected in the water, but that could be swept out by the flow.

I think the readings 'at' exactly 1000 mSv/hr may be redlining the dosimeters.  An expert on NHK news said something to that effect a few minutes ago.  I haven't seen much by way of credible, close-in air readings lately.  The readings should drop off very rapidly with distance.


Commander Cody's picture

I would like to know what sort of instrumentation is being used for these readings.  Without power, it would seem operators are taking local measurements.  Not a pleasant job.  Anybody have an idea or facts?

As for core and containment pressures being about equal, that suggests the vessels are in equilibrium with the containments.  It is possible that the seawater pumping has filled up the containments to some level, possibly to the core levels indicated if safety valves are open.  This also raises the possibility that reactor water is now flowing out through main steam or feed water lines into the turbine building.  This should not have occurred as isolation valves in those lines should have closed when the reactors tripped at the time of the earthquake.

It is most probable that there has been extensive core damage at Units 1-3.  That being so, then core material in the turbine building suggests that the reactor vessels are backflowing into the building (condensers, etc.) or the containments might be leaking and flooding the building basements with drain flows into the turbine building.  All this is a function of plant design.

Jim in MN's picture

I am thinking piles of pellets in the bottoms of the reactor vessels, but covered in water, with partially intact rods/assemblies sticking up above the water level.  Lots of steam/hydrogen.  A witches cauldron.

Agree with your take on the containment and backflow.  But it is very, very bad backflow (see post lower down)...turbine building, outside trenches, and lots of radiation in the water.

flattrader's picture


Did you see this vid from yesterday?

It's a fly by of the reactors. #3 looks like the cap of the outer steel containment vessel is blown off and to the left side of the camera frame. Start looking at about 2.55 mins.

At 3.05 mins. a poster noted a reactor shape to the right of the screen shot leaning against a concrete wall.

Compare to this infographic--

which, if accurate tells me we are in deep shit.

I can only assume the rod cooling pools for #3 are at best badly damaged and at worse gone completely.

Jim in MN's picture

TEPCO topiary, bottom right landscaping at 0:38

Unit 1, can't see anything in there.

Unit 2, ditto.  Steam coming out of at least three holes in the building.

Unit 3, twisted steel with steam.

Unit 4 is the one with the reactor vessel visible.  The entire core should be in the spent fuel pool.  The pool appears to have a massive beam or substructure collapsed right onto it.  You can see the concrete wall of the pool itself kind of hanging there, with this big giant beam across it, and steam just shooting out of there.

I have been figuring that unit 3's pool more or less fell into the hole and on to the reactor vessel, but have not gotten any good looks at the core or the pool at #3.

Ident 7777 economy's picture

I have been figuring that unit 3's pool more or less fell into the hole and on to the reactor vessel,

- - - - - - - - - - - - - - - - - - - - - - - -

Whoa! Do you know what the containment vessel is built of?

The reactor vessel is inside that upside down light bulb-shaped containment structure, and that's not an insignificant structure strength-wise ...


Jim in MN's picture

Yah, the pool would have bounced off the containment vessel (thanks for the correction).  Maybe the rods are still in it.  Maybe not.

Are you getting the idea that the reactor buildings are basically black boxes that have been shook, tsunami'd and exploded?  'Let's Make A Deal' surprise packages awaiting human or remote exploration.

Ident 7777 economy's picture

Yeah, I don't know what to expect ... except that the parts that are built to withstand pressure are still covered (reactor and containment vessels) so those are hard to determine as to integrity (pressure readings are all we have to go on) ... the cabling and piping to/from the reactor are BIG question marks ...

Commander Cody's picture

Vessel/containment pressures are atmosheric suggesting containment failures or deliberate venting paths.  I suspect the Unit 3 explosion was a catastrophic containment failure.  Watch the clip and see the well-defined cylindrical plume going straight up from the center of the building.

Ident 7777 economy's picture

Vessel/containment pressures are atmosheric suggesting containment failures 

- - - - - - - - - - - - - - - - - - - -

My obs too, going by the numbers in these guy's report (just didn't want to say it):

Also figure in the 3 audible booms ('reports') heard on the audio when #3 went up; the first one seemed to be the fireball which was sucked back in just prior to the plume seen going up ...


Confuchius's picture

In this Russian video about Chernobyl one can see that the Russians tried "robot" payloaders etc. for cleanup, which were quickly immobilized by the ionizing radiation.

Ident 7777 economy's picture

In this Russian video about Chernobyl one can see that the Russians tried "robot" payloaders etc. for cleanup, 

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

Not only that, who services the robots once they become irradiated and then 'hot' radioactively speaking?


Do they have a mobile 'hot cell' for servicing them (I would suppose they would, but only if and only if the robots were designed for that highly radioactive environment) ...



Ident 7777 economy's picture

Based on the news story this was part of, this is what things look like during refueling ops of a GE Mark I design (water level is brought up and a 'water' path made over to the fuel storage pool so the rods never 'see air'):


Here is the cap (cap of containment vessel) being lifted by the resident crane, but this may not be an actual cap of a GE Mark I design:



Ident 7777 economy's picture

by flattrader, Mon, 03/28/2011 - 10:17 #1108445 

Jim, Did you see this vid from yesterday?

It's a fly by of the reactors. #3 looks like the cap of the outer steel containment vessel is blown off and to the left side of the camera frame. Start looking at about 2.55 mins.

- - - - - - - - - - - - - - - - - - - - - - - - -

If I'm not mistaken, that looks like building #4 (roof trusses are still attached to some vertical concrete wall structures) ... but that is weird to see that orange thing sitting there ...


FEDbuster's picture

Three words jumped out at me when a scientist was talking about he reactor mess on TV last week, "molten radioactive goo".  When something is described as MOLTEN RADIOACTIVE (fucking) GOO, the situation cannot be good.

UninterestedObserver's picture

" A partial meltdown of fuel rods in the No. 2 reactor probably caused a jump in the readings"

Don't worry sheep - and  don't forget to drink your milk

High Plains Drifter's picture

well as far as fish products are concerned. you have a choice down south. either delicious radiated fish , or delicious oily fishy. its your choice. Bon Appetit

Stuck on Zero's picture

You can always buy fish and shrimp grown in Yangtze River water! 

FranSix's picture

I see they're using the "g" word.

You would get blobs of goo from the top of the melted fuel rods pooling in the bottom of the core as the water level decreased inside the core.

The only mitigating factor I can see in a core meltdown would be that the control rods melted along with the fuel, mixing in with it.

The reactor core is 16cm thick steel, and the outer containment vessel is 3cm thick.  There's lots of non-fissile material that can mix with the goo.

This would also have produced one heck of a lot more hydrogen in the process, should there have been any water left at all inside the core.

So more venting of radioactive steam, and a possible core breach.