Japan Earthquake: Nuclear Plants at Fukushima Daiichi

[SteveElbows]

Thank you, very helpful again.
You have more dedication that I do, to pore over the TEPCO releases that carefully.

Am still a little surprised by SPF 4, as the sharp decline in emissions was pretty exactly coincident with the spraying of water onto it, around Mar 19 if memory serves. There must have been something else happening concurrently that was not adequately appreciated.

Too many things occurred within short time periods, its hard to be certain. For instance the initial fire department spraying of pools started on the 19th but they started with reactor 3 pool, and if I remember correctly they didn't start on reactor 4 pool till the 20th. Somewhere around then they also pumped water into reactor 2 fuel pool using an existing piping system. It is also quite questionable as to how successful these spraying attempts were, we saw video of some parts of reactor 3 spraying at this point, and it was a bit of a struggle. Only with the arrival of the concrete pumping equipment did confidence increase that the pools were being replenished effectively.

The same is true for one of the other factors which caused unit 4 fuel pool concerns in the first place, the fact that the estimates for release to the environment were so high on that day, and detected levels on site rose considerably. But since something happened at reactor 2 on the same morning, its not possible to attribute this to reactor 4 pool with any certainty.

I don't like to draw solid conclusions due to the quality of the data and unanswered questions, the fuel in pool 4 may not be in completely perfect health. But if some of the really bad scenarios for this pool had readily happened, I would have expected to see more evidence of this by now, rather than workers busy operating in that area of reactor 4. The possibility of the pool collapsing seems to have been a real enough risk that they spent time constructing a support structure underneath, but once this was done my attention largely turned elsewhere. If some new piece of data or fact emerged I would take interest, but most of the big questions I dwell on these days relate to reactor 2. And at some point more detail of reactor 3's fuel pool will become clear, which may or may not be noteworthy.

 

[zapperzero]

Has anyone been trawling through the NRC FOIA releases?

I have just started but I find it rather hard going. Some things are just par for the course for the NRC - the text appears to be scanned off hardcopy and is not OCR'd properly. There are lengthy deletions too. Some of the contributions from people such as DOE reps and someone from "Pan Asia" -whatever that means- are entirely blacked out, there are entire telephone conferences which have been recorded and transcribed, but the entire transcript is blacked out and not even a list of participants is available.

Some bits and pieces, from here:
pbadupws.nrc.gov/docs/ML1205/ML12052A109.pdf

There's supposed to be a lot of GE folks over there doing refueling anyway

REDACTED: You know, we, we'll sort of stepped back, once the two,
Tepco and USFJ got together because obviously --

[about Unit 3 blowing, as far as I can tell]:

my worst fear has been that we, we finally got the steam explosion. breached the primary containment.

these are all conversations being had on the 14th I believe.

Also kindly look on page 258 - I am summarising here because I can't be bothered to transcribe it:

a certain Jack Grob is saying that
- unit 2 has just gone boom
- there is a wind towards the SW
- there is a US carrier in port 10 miles SW of Tokyo and it's measuring 10-20 mrem TEDE over 12 hours and roughly 10 times that thyroid dose.

Following pages are all about disbelief and checking these numbers and working back to what the dose rate may be on-site and a lot of oohing and aaahing.

Then even later (pp 278 and following) there is this Jim Trapp guy who's saying the data he got from a NISA engineer is that there is no water in SPF#4, there is a fire somewhere in there and the dose rate at the site boundary is 10 rem/hour (that would be 0.1 Sv/h).

 

[jim hardy]

109 ?? I read 107 and 108, will have to find yours.

What i got from those two is they were guessing as much as the rest of us.
All real information has been redacted.

Search on "pipermail fukushima" is more informative.

 

[tsutsuji]

Has anyone been trawling through the NRC FOIA releases?

I have read a part of http://pbadupws.nrc.gov/docs/ML1205/ML12052A105.pdf. I was surprised with their discussion of the 1.5 mrem/hour claim by a Yokosuka base admiral (page 245 - 247/296) without any comparison with any other Yokosuka measurements that might be available from civilian sources, such as http://www.bousai.ne.jp/vis/jichitai/kanagawa/ . Did they know that there is something called "the internet" where one can find data ?

 

[zapperzero]

I have read a large part of http://pbadupws.nrc.gov/docs/ML1205/ML12052A105.pdf. I was surprised with their discussion of the 1.5 mrem/hour claim by a Yokosuka base admiral (page 245 / 247/296) without any comparison with any other Yokosuka measurements that might be available from civilian sources, such as http://www.bousai.ne.jp/vis/jichitai/kanagawa/ . Did they know that there is something called "the internet" where one can find data ?

I read in the document I referenced something about NRC interacting with NISA via a translator. I doubt anyone at the decision-making level in NRC knows any Japanese and from personal experience I can attest it's pretty hard to get in-depth info about Fukushima when you don't have tsutsuji on your team.

 

[Thalic]

I read in the document I referenced something about NRC interacting with NISA via a translator. I doubt anyone at the decision-making level in NRC knows any Japanese and from personal experience I can attest it's pretty hard to get in-depth info about Fukushima when you don't have tsutsuji on your team.

Well put ZZ. I too really appreciate tsutsujisan.

 

[Shinjukusam]

Very big props for tsutsujisan. He's single-handedly keeping me from studying harder ;)

 

[Borek]

tsutsuji-san devotion is remarkable

 

[jim hardy]

Amen to that .

Thank you, Tsutsuji.

 

[Yamanote]

Yesterday they removed the big overhead crane of unit 4. Good job.

http://www.tepco.co.jp/en/nu/fukushima-np/images/handouts_120306_01-e.pdf

 

[tsutsuji]

http://www.yomiuri.co.jp/science/news/20120303-OYT1T00456.htm A team led by Hidesada Tamai of JAEA will make a presentation about unit 1's meltdown at the Japan Atomic Energy Society meeting in Fukui on 20 March. Together, the two IC systems were supposed to supply cooling for 16 hours. If they had been turned on within 1 and a half hour, the meltdown could have been averted.

http://www.aesj.or.jp/meeting/2012s/e/12Spr_program18-44.pdf page 20 :
B12 : Hidesada Tamai (JAEA) Study of progression until core uncovering at Fukushima Daiichi unit 1, using TRAC-BF1 (1) shift of coolant distribution inside reactor
B13 : --------------- (2) Consequences on reactor cooling by Isolation Condenser

 

[SteveElbows]

Yesterday they removed the big overhead crane of unit 4. Good job.

http://www.tepco.co.jp/en/nu/fukushima-np/images/handouts_120306_01-e.pdf

Yeah, visible progress at reactor 4 building has been notable and good to see. Quite the contrast to reactor 3 upper building where progress looks, from the very few images we have seen recently, to be painfully slow.

By the way since reactor 4 has come up again a few times in conversation recently, I thought I would mention the shroud. Back in the day some of us were interested as to what stage the core shroud replacement had reached at the time of the accident. I can't remember whether we ever found out, but I just noticed that one of the ICANPS interim report attachment documents has a diagram that shows the shroud located in the dryer separator pit ( http://icanps.go.jp/eng/120224Siryo04Eng.pdf page 165/attachment IV-40 ). May have seen a very similar diagram in the past but I thought Id mention it just in case we hadn't. edit - I went back and checked and I was talking about a very similar diagram at the end of June so this isn't news.

 

[Yamanote]

Together, the two IC systems were supposed to supply cooling for 16 hours. If they had been turned on within 1 and a half hour, the meltdown could have been averted.

This fact still drives me nuts...

As there is less destruction and radiation at unit 4, it is easier to make progress there and it makes imho sense to secure the spent fuel pool asap. At least the crane can't fall into the pool during an earthquake anymore...
As for units 1 to 3, radiation and contamination still seems to be too high to extend works, so they have to wait until radiation has declined. I don't think it makes sense to send in more people at that point in time. For the reactor cores the damage is more or less done, I see more danger coming from the spent fuel ponds, where a meltdown is still possible.

By the way - I saw a picture of a nuclear power plant (I guess it is one in Canada) with eight reactors very close to each other. Such a plant layout appears to be quite dangerous with respect to the events in Fukushima.
What's your opinion on that?

 

[al2207]

it is Pickering in Ontario much less dangerous ( no big earthquake fault near )
even if they loss all exterior power Candu can still produce up to 40 % of power generation for internal use and dump the rest of steam in condensing unit

 

[jmelson]

Yesterday they removed the big overhead crane of unit 4. Good job.

http://www.tepco.co.jp/en/nu/fukushima-np/images/handouts_120306_01-e.pdf

Ah ha! I expected that this was one of the big things they could start working with, unloading
the SFP of #4, and that was going to require removing a lot of damaged equipment that
would be in the way. Unloading the fuel from that pool will be a very tricky bit of work using a traditional crane which has no way to orient the hook like a FHM does. The unused fuel
can just be pulled out, the old fuel might be able to be removed under water deluge, but the
recently burned fuel will be quite a challenge to remove. Possibly they can still use transfer
casks to get it out of there, one element at a time.

The rest of the reactors are too hot to do a lot of work on at least for several years.
Maybe some of this endoscope work will at least allow them to figure out where the
fuel is, and maybe eventually some of the other fuel pools can be emptied, also.

Jon

 

[Joffan]

Unloading the fuel from that pool will be a very tricky bit of work using a traditional crane which has no way to orient the hook like a FHM does. The unused fuel
can just be pulled out, the old fuel might be able to be removed under water deluge, but the
recently burned fuel will be quite a challenge to remove. Possibly they can still use transfer
casks to get it out of there, one element at a time.

My thought was that they might construct a water channel and tower on one side of the spent fuel pool, then take fuel out into a (new) ground-level pool through a lock, in water the whole time. But there might be craned solutions that are simpler and indeed safer over the whole operation.

it is Pickering in Ontario

- or Bruce on Lake Huron. But the same considerations apply.

 

[thebluestligh]

http://pbadupws.nrc.gov/docs/ML1110/ML11102A041.pdf

MEMBER CORRADINI: The only reason I ask the question is, from the same public sources I think we are all looking at, Unit 1 is the only one that is showing pressurized.

MR. RULAND: That's correct.

-----

MEMBER ARMIJO: I've been there, (Japan) you know from a hazy recollection, they were very similar, if not identical, to the U.S. plants. But I have heard all sorts of stories that they were different, and I had wondered -- I would like to know if the NRC has drawings of the plants as they currently exist.

The other thing I know about the Japanese, they were very careful to follow the safety upgrades that the NRC required in the U.S. plants---CHAIRMAN ABDEL-KHALIK: Now, with regard to the spent fuel pools, it is my understanding that the emergency operating procedures used by the Japanese are similar to those used at U.S. plants.

And for both BWRs and PWRs, the emergency operating procedures focus on maintaining the critical safety functions of the reactor.

Nowhere in the EOPs are the operators asked to check the status of the spent fuel pools.

Given what happened at Fukushima with regard to the spent fuel pools, should the licensees be asked to evaluate the adequacies of their EOP?---

And with a hardened vent -- the vent, prior to the venting operation, still filled with oxygen, so the chance of a deflagration inside the vent is real, if you vent hydrogen through that.

 

[Rive]

Unloading the fuel from that pool will be a very tricky bit of work using a traditional crane which has no way to orient the hook like a FHM does.

As I understand this for unit 4 they will use external cranes only to move the transfer casks to- and from the pool, and they will repair and use the FHM to move the fuel within the pool to the transfer casks.

But first they will have to repair the FHM of the common pool and start to prepare it to receive the removed fuel from unit 4.

 

[triumph61]

It looks like that the Fuelhandlingmachine (upper Part) is also removed.

 

[Rive]

That's just the overhead crane trolley and the main beams. The FHM is still in place.

 

[triumph61]

1. Picture: look at the right side. The upper Part is visible.
2. Picture : The upper Part is no longer visible.
3. Picture: Left side, maybe there is the upper part of the FHM.

 

[Rive]

Oooops. Yes, you are right. That thing on the third picture is the trolley of the FHM.

 

[tsutsuji]

http://www3.nhk.or.jp/news/genpatsu-fukushima/20120307/0920yoken.html At a symposium in Washington about the Fukushima Daichi accident, Commissioner Apostolakis said "the consequences of a tsunami could have been predicted". The symposium organiser, the Carnegie Endowment for Peace, is also releasing a report on "Why Fukushima was preventable", saying that the analysis of historical tsunamis was not sufficient and that in contrast with the measures taken in Europe after the French NPP flooding and blackout of 1999 or in the US after the 11 September 2001 attacks, Japan was negligent to take countermeasures against blackout.

http://carnegieendowment.org/2012/03/06/one-year-on-assessing-fukushima-s-impact/9iid Symposium

http://carnegieendowment.org/files/fukushima.pdf report: James M. Acton and Mark Hibbs, "Why Fukushima was preventable"

 

[etudiant]

http://www3.nhk.or.jp/news/genpatsu-fukushima/20120307/0920yoken.html At a symposium in Washington about the Fukushima Daichi accident, Commissioner Apostolakis said "the consequences of a tsunami could have been predicted". The symposium organiser, the Carnegie Endowment for Peace, is also releasing a report on "Why Fukushima was preventable", saying that the analysis of historical tsunamis was not sufficient and that in contrast with the measures taken in Europe after the French NPP flooding and blackout of 1999 or in the US after the 11 September 2001 attacks, Japan was negligent to take countermeasures against blackout.

http://carnegieendowment.org/2012/03/06/one-year-on-assessing-fukushima-s-impact/9iid Symposium

http://carnegieendowment.org/files/fukushima.pdf report: James M. Acton and Mark Hibbs, "Why Fukushima was preventable"

Seems nuclear management in Japan after thirty plus years of operations free from disaster suffered from the same 'Victory Disease' as that which afflicted Japanese leadership in the early days of WW2.
It is very hard to stay careful when things work well for a long time.

 

[jmelson]

As I understand this for unit 4 they will use external cranes only to move the transfer casks to- and from the pool, and they will repair and use the FHM to move the fuel within the pool to the transfer casks.

But first they will have to repair the FHM of the common pool and start to prepare it to receive the removed fuel from unit 4.

Ok, that seems a lot safer, but the problem is that repairing the FHM and being sure it is completely reliable will be a huge effort, due to the structural damage to the entire building. The FHM itself could be pulled out by crane and moved elsewhere for repairs, but the tracks it runs on have to be guaranteed to handle the load and be transited in so the FHM can travel in the proper plane.

Jon

 

[jmelson]

Seems nuclear management in Japan after thirty plus years of operations free from disaster suffered from the same 'Victory Disease' as that which afflicted Japanese leadership in the early days of WW2.
It is very hard to stay careful when things work well for a long time.

See also Challenger accident and Columbia accident. "It hasn't killed anybody yet, so it can't be a big risk."

Jon

 

[mheslep]

See also Challenger accident and Columbia accident. "It hasn't killed anybody yet, so it can't be a big risk."

Jon

That's a half-appropriate comparison. Yes organizations can and have misjudged the risk of accidents, but clearly the consequences of the one (Challenger) means 100% fatalities, while the other with containment equipped reactors means large capital losses and economic damage, but zero fatalities, so far.

 

[jmelson]

http://www3.nhk.or.jp/news/genpatsu-fukushima/20120307/0920yoken.html At a symposium in Washington about the Fukushima Daichi accident, Commissioner Apostolakis said "the consequences of a tsunami could have been predicted".

Wow, what an understatement! Anybody who was analyzing safety should have put this together pretty easily. It seems the Japanese government allowed TEPCO WAY too much
leeway to set their own rules and safety management.

But, of course, anybody who was let into give Fushima Dai-ichi #1 a complete review
would have demanded it be shut down immediately. And, the rest of the plants there would have only gotten a slightly better review. There were so MANY features of the plant that compromised survivability, it would have made it almost impossible to bring these plants up to reasonable standards. Once you put practically the entire electrical safety system in the basement of a building only meters from the ocean, both horizontally and verticaly, you have a HUGE problem. Then, there was so much ELSE vulnerable to the tsunami, like EDG fuel tanks. Just a mess. Fixable, but it would cost a couple billion $ to retrofit just the plants
at this one location.

Jon

 

[jmelson]

That's a half-appropriate comparison. Yes organizations can and have misjudged the risk of accidents, but clearly the consequences of the one (Challenger) means 100% fatalities, while the other with containment equipped reactors means large capital losses and economic damage, but zero fatalities, so far.

There indeed WERE fatalities at the plant, although not related to safety systems, but just
people being at the lower levels of the buildings when the tsunami came in. it is kind of a miracle
nobody was killed by falling debris, etc. when the explosions happened.

This accident has caused major radioactive contamination of a large area of Japan, deaths are really hard to associate with such an event, but this is a HUGE, widespread consequence that is not over yet. Radioactive soil will be dug up and cause further contamination for years to
come. There are still areas where farming is not permitted, produce will need to be tested
for radioactivity for years, it is a HUGE mess. The entire nation of Japan will have a big power shortage this summer, it will be interesting to see how they cope with it. It is definitely affecting their whole national economy.

But, I was mostly trying to draw a comparison between assessing risk in very complicated systems, and the cultures that manage such systems.

Jon

 

[mheslep]

There indeed WERE fatalities at the plant, although not related to safety systems,

Though not related to anything having to do with nuclear power.