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Fukushima Daiichi Nuclear Accident – 26 March status

This post provides an update to the various situation summaries at Fukushima Daiichi. Please switch to using this post for comments on the latest status reports and news to  hand (the old one is now out of date). For general comments on, use the FD Open Thread #2, and for analysis of the event with respect to future lessons for nuclear power, use this post. Full situation summaries from TEPCO, FEPC and JAIF are given at the bottom of this report.

This is a dramatic before and after photo of the Fukushima Daiichi plant. Click on the image to see more b/a images of the earthquake/tsunami damaged Sendai region (controlled with a swipe tool).

Below is a very brief summary of some key events of the last few days, since the previous status report:

1. There has been concern about salt accumulation in reactor vessels 1-3 (as steam evaporates the injected sea water, the salt is left behind, and if concentrations build to beyond the saturation point, it will begin to deposit and potentially insulate the fuel assemblies). However, NEI now reports the following welcome news:

Fresh water is being injected into the reactor pressure vessel at reactor 3 at Fukushima Daiichi nuclear power plant, Japan’s Nuclear and Industrial Safety Agency said.

TEPCO said that radioactive materials discovered at the reactor 3 turbine building possibly came from water from the reactor system, not the spent fuel pool. TEPCO made that statement after collecting samples of contaminated water in the reactor 3 turbine building and conducting a gamma-emitting nuclide analysis of the sample. The reactor pressure and drywell pressure at reactor 3 remained stable on Friday, leading TEPCO to believe that “the reactor pressure vessel is not seriously damaged.

Cooling efforts at Reactor 1 already had switched back to fresh water cooling. Reactor 2 is still being injected with seawater, but is expected to switch to fresh water soon.

The temperature at the bottom head of the reactor pressure vessels are now 149 C (unit 1), 104 C (unit 2) and 111 C (unit 3) — detailed data in reports below.

2. TEPCO Workers laying cables in the turbine hall of unit 3 stood in ankle-deep stagnant water and their feet were irradiated with beta rays (~180 mSv dose), with shallow burns, after ignoring their dosiometer warnings. They have since been hospitalised. Details in the reports below. 17 personnel have now received doses of >100 mSv, but none >250 mSv — the dose allowed by authorities in the current situation.

3. Water spraying continues on spent fuel ponds 2, 3 and 4, to ensure the uranium fuel rods remain covered. The temperature in unit 2 pool was recently measured at 52 C (see detailed data below).

4. On radiation: levels around the plant perimeter are relatively low and steadily decreasing. Levels of I-131 in drinking water supplies in Tokyo are now below regulated limits and restrictions have been lifted. The IAEA radiation monitoring data, at a distance of 34 to 62 km from Fukushima Daiichi, showed very low levels. To quote:

On 25th March, the IAEA radiation monitoring team made additional measurements at distances from 34 to 62 km from the Fukushima nuclear power plant. At these locations, the dose rate ranged from 0.73 to 8.8 microsievert per hour. At the same locations, results of beta-gamma contamination measurements ranged from 0.07 to 0.96 Megabecquerel per square metre.

5. World Nuclear News provides a new summary: Fukushima Daiichi two weeks on. To quote:

Investigations are now underway into the unexpectedly high level of contamination in the water, particularly as the basement of the turbine building is not a recognised radiation area. One theory is that there is a leak from the reactor circuit, but pressures in the reactor vessel indicate this must be elsewhere in the loop.

Despite this disappointment, steady progress continues to be made on site. Instrumentation is being recovered at units 1, 2 and 4 and lights are on in the control rooms of units 1 and 3. Power connections have reached all the units and checks are underway before normal systems can be re-energised. The shared pond for used fuel pond has now been reconnected.

Here are some interesting photographs from inside the buildings, taken on 23 March by by the Operational Safety Inspector.

6. Geoff Russell (a regular BNC author on food and climate change issues) has a really good piece, reflecting on many of the issues discussed here over the last few weeks. His original title was: Japanese nukes … good news in a bleak landscape.

Some useful technical details are available from NISA Major Parameters 1800 March 25, and the NISA summary conditions report for each reactor (click on the diagram below to access the PDF):

Below is a situation update of the Fukushima Daiichi site, from TEPCO Washington office:

——————————

(1) Result of the investigation on highly radiated workers.

Below are the investigation results of their working environment. Radiation dose rate of surface of the water is approximately 400 mSv/h. Result of gamma-ray nuclide analyses based on sampling of the stagnant water on the basement floor of the turbine building of Unit 1 of Fukushima Dai-ichi Nuclear Power Station. We are assessing radiation dose of 2 worker’s leg skin by beta ray. This incident would be caused because the workers regarded radiation dose of working area as low from survey result of radiation dose on March 23, it was about 0.5 mSv/hr at 5:00 and no major water puddle there. Workers continued working without recognizing change of work environment although their APD were alarming during the work TEPCO has thoroughly instructed its employees and contractor workers to pay attention to the alarm of their APD and evacuate when necessary.

Regarding this event, Fukushima Labor Bureau gave TEPCO verbal instructions. After summerising lessons learned and future measures to this event, TEPCO will report related government ministries and agencies to make sure radiation control thoroughly.

(2) High radiation water may come from the unit 3 reactor, not spent fuel pool.

As for the leakage of radioactive materials at Unit 3 turbine building, we assume the water came from the reactor. We collected sample of the contaminated water in the turbine building of Unit 3 and conducted the gamma-emitting nuclide analysis. We confirmed the following nuclides with short half-life.

Nuclides              half-life (days)     density (bq/cubic centimeter)

Iodine 131              8.06                              1.2 x 10E6

Cesium 136          13.16                             2.3 x 10E4

Barium 140            12.75                            5.2 x 10E4

There are 148 fuel rods with less than one year of cooling period in the spent fuel pool at Unit 3. Those fuel rods were transferred to the spent fuel pool between Jun 23 and 28, 2010 having had more than 200 days of cooling period. Nuclides with short half-life had sufficient time for decay in the spent fuel pool, so it seems possible that the contaminated water in the turbine building is from the reactor.

We do not deny possibility that there might be certain damage to the reactor of Unit 3. Even should that be the case, as plant parameters such as the reactor pressure and D/W pressure is stable , we presume that RPV is not seriously damaged.

We are injecting seawater and from the night of March 25, fresh water into the reactor. The water turns into steam and comes out from the reactor vessel through the SRV, then depressurized at the suppression chamber and condensed to water. This flow of water is cooling the reactor. Having experienced fluctuations of temperature and pressure, the containment function might be loosened somewhere. In any event, the above is a possibility, not yet confirmed.

(3) Water injection into the pools and the reactors.

Unit 1: Sea water injection into the reactor pressure vessel, from 3:37 pm on March 25th, we have started to inject fresh water into it.

Unit 2: From 10:30 am on March 25th, seawater injection through Fuel Pool Cooling and Filtering System (FPC) was started. This finished at 0:19 pm.

Unit 3 From 5:35 am on March 24th, seawater injection through Fuel Pool Cooling and Filtering System (FPC) was started and finished at 4:05 pm.

Spraying at the spent fuel pool by Kawasaki City Fire Department was carried out from 1:28 pm to 4:00 pm on March 25th.

Unit 4: From 2:35 pm on March 24th, spraying water by the concrete pumping vehicle was conducted and ended at approximately 5:30 pm on the same day.

From 6:05 am on March 25th, seawater injection through Fuel Pool Cooling and Filtering System (FPC) was started and finished at 10:20 am.

————————–

Here is the latest FEPC status report:

  • Radiation Levels
    • At 7:00PM (JST) on March 25, radiation level at main gate (approximately 3,281 feet from Unit 2 reactor building) of Fukushima Daiichi Nuclear Power Station: 199.5 micro Sv/hour.
    • Measurement results of environmental radioactivity level around Fukushima Nuclear Power Station announced at 7:00PM on March 25 are shown in the attached PDF file. English version is available at:    http://www.mext.go.jp/english/radioactivity_level/detail/1303962.htm
    • For comparison, a human receives 2,400 micro Sv per year from natural radiation in the form of sunlight, radon, and other sources. One chest CT scan generates 6,900 micro Sv per scan.
  • Fukushima Daiichi Unit 1 reactor
    • At 11:00AM on March 25, activities for the injection of freshwater in place of seawater into the reactor core started and at 3:37PM, the injection of freshwater into the reactor core started.
    • At 2:00PM on March 25, pressure inside the reactor core: 0.342MPa.
    • At 2:00PM on March 25, water level inside the reactor core: 1.65 meters below the top of the fuel rods.
    • At 2:00PM on March 25, pressure inside the primary containment vessel: 0.280MPaabs.
  • Fukushima Daiichi Unit 2 reactor
    • At 10:00AM on March 25, the temperature of the spent fuel pool: 82.4 degrees Fahrenheit.
    • At 10:30AM on March25,　TEPCO began to inject seawater into the spent fuel pool via cooling and purification line, until at 12:19PM (approximately 38 tons in total).
    • At 11:00AM on March 25, activities for the injection of freshwater in place of seawater into the reactor core started.
    • At 2:00PM on March 25, pressure inside the reactor core: -0.016MPa.
    • At 2:00PM on March 25, water level inside the reactor core: 1.4 meters below the top of the fuel rods.
    • At 2:00PM on March 25, pressure inside the primary containment vessel: 0.12MPaabs.
    • As of 7:00PM on March 25, approximately 96 tons of water in total has been injected into the spent fuel storage pool.
    • As of 7:00PM on March 25, external power generation is connected and the functionality of the electric devices is being checked.
    • As of 7:30PM on March 25, the injection of seawater into the reactor core continues.
  • Fukushima Daiichi Unit 3 reactor
    • At 11:00AM on March 25, activities for the injection of freshwater in place of seawater into the reactor core started and at 6:02PM, the injection of freshwater into the reactor core started.
    • At 1:28PM on March 25, Kawasaki City Fire Department began to shoot water aimed at the spent fuel pool until 4:00PM (approximately 450 tons in total).
    • At 2:00PM on March 25, pressure inside the reactor core: 0.038MPa.
    • At 2:00PM on March 25, pressure inside the primary containment vessel: 0.1089MPaabs.
    • At 2:10PM on March 25, water level inside the reactor core: 1.9 meters below the top of the fuel rods.
    • As of 7:00PM on March 25, approximately 4,497 tons of water in total has been shot to the spent fuel storage pool.
  • Fukushima Daiichi Unit 4 reactor
    • At 6:05AM on March25, TEPCO began to inject seawater into the spent fuel pool via cooling and purification line, until at 10:20APM.
    • At 7:05PM on March 25, TEPCO began to shoot water aimed at the spent fuel pool, with a specialized vehicle normally used for pumping concrete.
    • As of 7:00PM on March 25, approximately 685 tons of water in total has been shot to the spent fuel storage pool.
    • As of 7:00PM on March 25, external power generation is connected and the functionality of the electric devices is being checked.
  • Fukushima Daiichi Unit 5 reactor
    • At 3:00PM on March 25, the temperature of the spent fuel pool: 98.4 degrees Fahrenheit.
    • At 3:00PM on March 25, the temperature of the water in the reactor core: 129.0 degrees Fahrenheit.
  • Fukushima Daiichi Unit 6 reactor
    • At 3:00PM on March 25, the temperature of the spent fuel pool: 69.8 degrees Fahrenheit.
  • Fukushima Daiichi Common Spent Fuel Pool
    • As of 7:00PM on March 25, approximately 130 tons of water in total has been injected to the spent fuel storage pool.

——————————

Finally, the latest Japan Atomic Industrial Forum summary table (21:00 March 25):

By Barry Brook

Barry Brook is an ARC Laureate Fellow and Chair of Environmental Sustainability at the University of Tasmania. He researches global change, ecology and energy.

259 replies on “Fukushima Daiichi Nuclear Accident – 26 March status”

According to the professor interviewed in the video at:
http://www3.nhk.or.jp/daily/english/27_12.html

They are planning on or already trying to pump the highly contaminated radioactive water into the main turbine condenser(s). This is to be used to store the water in order to allow work to continue in the basement of the turbine building(s).

This information is also given here:
http://online.wsj.com/article/SB10001424052748704396904576225961395484904.html

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@GallopingCamel – if you didn’t happen to keep a copy of your post that was deleted, I grabbed a copy, so just hollar & I can post it at one of the other threads for you.

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@ David Martin
Where in the air? In the reactor? Would still be no danger to the general public ouside the evacuation area.
The readings are per hour and go up and down. Comment anyone?

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Dunno for sure. Presumably in the reactor building, as that is where the irradiated water is reported. I’ve tried googling, but all I have turned up is more derivative articles, not the original statement by the guy.
Hopefully this is in error and the high levels are in the water, which is bad enough.

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Latest on BBC site:
BREAKING NEWS: Huge spike in water radiation at Japan’s quake-hit nuclear plant was a mistaken reading, company spokesman says

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@David,

It appears the Independent has rewritten the article and now includes this phrase

a spike that officials later said was inaccurate.

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Yes, they have said that they will do further analysis on the water at number 2 because of questions about accuracy of I-134 findings.

They also say that they were not able to measure total radiation there because the reading was too high for people to continue measuring.

This info is mentioned in the following story:

http://english.kyodonews.jp/news/2011/03/81345.html

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http://english.kyodonews.jp/news/2011/03/81266.html

TEPCO’s Fukushima office acknowledged Saturday that it had known earlier that the radiation in the underground level of the turbine building of one of the reactors was extremely high, but had not made the information available to pertinent parties.

Edano criticized the utility’s handling of the data, saying unless it reports necessary information to authorities in a timely manner, ”the government will not be able to give appropriate instructions and (TEPCO) will make workers, and eventually the public, distrustful” of the firm.

really, nothing new, same tactics of “delay bad news” from TEPCO.

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“..radiation level at main gate (approximately 3,281 feet from Unit 2 reactor building) of Fukushima Daiichi Nuclear Power Station: 199.5 micro Sv/hour.

For comparison, a human receives 2,400 micro Sv per year from natural radiation in the form of sunlight, radon, and other sources. ”

We see this kind of apples-oranges comparisons everywhere. Why compare a per year radiation with a per hour radiation ?

It should really be “natural radiation is 0.27 micro Sv/hour”.

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When the refilling of the reactor cores was recently changed from seawater to freshwater Tepco reported that it added boric acid to the freshwater feed of unit 2.

Such was NOT added to unit 1 and 3 freshwater feed.

http://www.tepco.co.jp/en/press/corp-com/release/11032702-e.html

Why is there, 16 days after shut down, still need to suppress fission in unit 2?

How does that relate to short half life nucleotides in the water in the unit 2 turbine hall?

Could the partial meltdown in no 2 have restarted some fission?

Any decent opinion on this?

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Sidd.

“I find it troubling that I-132, I-133, Ru-105, Te-129 are detected. These have very short half lives, and must have been recently created.”

I-132 is a decay product of Te-132, which has a 3.2 day half-life and should still be present in appreciable amounts.

Te-129 in ground state is troubling, as it has a 70 minute half-life and it’s longest lived parent nuclide has a half-life of only 4.4 hours. It is very possible that this is refering to Te-129m which has a 33.6 day half-life.

I-133 has a 20.8 h and could plausibly still be detectable in minute amounts with very sensitive equipment. Has no possible long-lived parent nuclides.

Ru-105 has a half-life of only 4.5 hours and only short-lived possible parent nuclides. This troubles me if detected in any quantity. There is always some level of spontaneous fission in actinides; especially from Pu-238, Pu-240, Pu-242, Am-241. To get a feel for the order of magnitude, a kilogram of pure Pu-240 produces 900 neutrons per second from fission; there is some amplifications as fission can be induced by neutrons in a shutdown reactor, but not with a probability high enough for a self-sustaining reaction; only a small fraction of fissions yield Ru-105. This just shouldn’t be detectablMODERATOR
This conversation is beginning to ramble off-topic. Please move to Fukushima Open Thread 2 where similar points are being discussed. Posting off-topic may result in deletion of your comment and a request to re-post on the correct thread.

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Here is a more detailed look at the conditions;

Click to access en20110327-2-3.pdf

than available from JAIF. I was struck by
1)lethal radioactive levels in drywell and suppression chamber.
2)reactor 1 is creeping up in temperature and pressure
3)water levels in 1 and 2 are falling, 3 has maintained a very low level, all in spite of water injection on the order of hundred liter/minute.

sidd

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sidd, I dont agree that water level in reactor 1 is falling, in fact its pretty stable and has risen very slightly over the last week, now stable around -1650 or -1600. Water at unit 2 has fluctuated anywhere from -1400 to -1000 since the 20th. And reactor 3s water measurements have been steady on -2300 for days according to measurement B, and fluctuating between -1900 and -1800 according to A.

My source is the same as the docuemnt you linked to, except I’ve had to go back and look at many of the previous releases of this info from the same source, in order to see the trends.

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Mr. Elbows, you are correct. My impression was based on the reactor 2 reading of -1100 mm on the 26th to -1200 on the 27th.

Steam is observed from reactor 1-4, is it of sufficient volume to account for the volume of water being pumped in ? I have not seen any video lately, perhaps someone who has might care to comment ?

sidd

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This may be new video of the reactor buildings from helicopter… I don’t speak Japanese, so if anyone here does, hopefully you’ll let us know about anything particularly interesting that was said – and more importantly perhaps, if it’s not actually from today as the time stamp suggests!

http://peevee.tv/v/84w992

I’d like to know how much of the ‘white smoke” is just steam escaping from SFP’s or all the water that has been sprayed – when ambient temps are cold as it apparently is, it doesn’t take water all that warm to steam a bit… think of heated swimming pools or your breath on cold days…

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More fun (NOT)

http://www.reuters.com/article/2011/03/27/japan-idUSL3E7ER06020110327

has bullet item: * Magnitude 6.5 quake in north Japan triggers small tsunami

These have got to be awfully disconcerting for those working at the site – heck, for ANYONE in N. Japan for that matter.

I have wondered on other threads just how many significant sized aftershocks have occurred at the Fukushima Dai-ichi site. I’m sure some official group must be counting, but I haven’t seen reports. Mainly because I worry about already damaged or stressed components having to take more abuse, and if something might give way given a large enuf shake. (obviously I’m not meaning another 9 EQ here, although anything is conceivably possible)

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Latest from TEPCO Washington

TEPCO announced the result it previously reported on the radioactive nuclide analysis was mistaken, Iodine-134 was overestimated.

Therefore we informed that we would take, analyze and evaluate samples, and announce the results once we have summarized the results.

Since then we have re-evaluated the density of the gamma nuclide including Iodine-134, and now we announce the summary of the results of the measurements as shown in the table bellow. (Iodine-134 is estimated as ND instead of 2.9 x 10E+9 Bq/cm3.

Cause of mistakes in the previous announcement.
–> Each radioactive material emits gamma ray or others of different energy level and the device of the nuclide analysis determines the nuclide based on the energy level and estimates the radioactivity density.
This time we determined that the nuclide was Iodine-134, judging from the gamma ray detected at 1,038 keV. But this 1,038keV peak consists a smaller part of the total gamma emission among the peaks used to identify Iodine-134. Reconfirming Iodine-134 by 846keV peak, Iodine-134 has not been detected and from this result we have realized that the judgment of iodine-134 detection by 1,038keV was wrong.

Actions taken forward
–> We will re-evaluate radioactive nuclides in the water puddle of other units as soon as possible. Also we will establish a data checking system in view of lessons learned from this mistake. When conduction nuclide analysis, information shall be shared with the headquarters and the site.

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JAIF update #32
Status of Fukushima Daiichi nuclear power station as of 17:00, March 27, 2011

Here is information regarding the status of Fukushima Daiichi nuclear power
station from the News Releases by the Government Nuclear Emergency
Response Headquarters and Nuclear and Industrial Safety Agency (NISA)
officials in the morning on March 27.

􀁺 According to the News Releases, high radiation level in the water was also
found in the basement of the turbine building of Unit 1, 2 and 3. The level of
radiation on the surface of water was more than 1000 millisieverts (mSv) per
hour in Unit-2, 60mSv in Unit-1, 750mSv in Unit-3. NISA officials believe
the contaminated water likely came from the reactor rather than the spent
fuel pool because the radionuclide detected contained in the fuel and some
had short half-lives.

TEPCO took immediate action to drain off the water
because current situation would cause delay in recovery work. TEPCO
already started draining off the water in Unit-1, and also preparing or
considering drain off the water in Unit-2 and -3. The water would be sent to
condensers in the turbine building.

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By Post Author

is this water in the turbine building from the sea water used to flood containment? and the water became highly radioactive from leaking pressure vessel?
[deleted unsupported hearsay. Please re-submit with ref/link]

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Rational Debate,
I have the M5+ shocks by day from 24 Mar and above 4.5 shocks from 27 Mar on plotted in google earth. I am not sure how to export the whole thing. I have a kmz from if that is good enough and people want it I will make a public link in dropbox for it and work to keep it updated. Let me know…

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re post by chavv, on 28 March 2011 at 12:46 AM (and others of similar vein) said:

TEPCO’s Fukushima office acknowledged Saturday that it had known earlier that the radiation in the underground level of the turbine building of one of the reactors was extremely high, but had not made the information available to pertinent parties.

Edano criticized the utility’s handling of the data, saying unless it reports necessary information to authorities in a timely manner, ”the government will not be able to give appropriate instructions and (TEPCO) will make workers, and eventually the public, distrustful” of the firm.

really, nothing new, same tactics of “delay bad news” from TEPCO.

Frankly I think claims like these are outrageously ironic, to the point of absurdity, when one considers that a single unverified reading winds up splattered across media articles literally around the world.

Frankly, a lot of this appears to be nothing more than after the fact CYA blame game. We’ve all known there were extremely high dose rate areas on site. Does each and every high dose rate area need to be reported to Edano or even the Gov the second they are found? Reported to every one of us?

They had measured dose rates in that area on several occasions – and what possible good would reporting the dose rate in the turbine building basement’s to the Gov. & Edano possibly have done? For that matter, we don’t even have any way of knowing that those very rates WEREN’T reported to the Gov – we only know that Edano is claiming that they weren’t done so in a timely fashion.

Claims get made that TEPCO didn’t take sufficient precautions to keep the 2 (3?) workers from being over exposed – well, yes, rather by definition that is true no matter WHAT precautions were or weren’t taken – they got overexposed. So TEPCO cowtows and says, yes, we were wrong, we didn’t handle it well. What else could they possibly say, and isn’t that the Japanese cultural tendency anyhow?

Should they have had rad tech’s in there with them? Possibly – possibly not. They were wearing alarming dosimeters and were trained in using them. We don’t know if rad tech’s checked the work area immediately before those workers started in the basement area – they should have. But even if they had, it is entirely possible that the water wasn’t there when the work started. How many rad techs tdo they have available and how many other high dose rate areas have work going on, and how many other locations must be periodically checked and/or checked prior to other work starting in those areas? Every rad tech you have babysitting workers is yet another person who’s dose is going up – rad techs are often used in a roaming fashion as a result – either checking areas just prior to work starting to be sure conditions haven’t changed appreciably, or periodically poking in to be sure they haven’t changed while the workers are there. And to be sure workers are where they are supposed to be, and not off in some even higher dose rate area.

In other words, you have to manage your pool of available rad techs for their time, dose, and even the total number you have vs. the work that must be done very rapidly in emergency situations like this –
and prioritize accordingly. It is awfully easy to say after the fact that something wasn’t done right.

Would I personally like to see more detailed information, sure – but that’s an entirely different issue and has no reflection on whether any information is being “hidden” or “delayed” or what have you. They have far more important things to do than be sure that the cheering (or booing) section out here is up to date on the details. Somehow I just have a very hard time with the idea of all this supposed TEPCO secrecy and skullduggery when a single unconfirmed dose rate in a single area winds up being international news.

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[comment deleted.Off-topic – does not relate to Fukushima daily up-date – please re-post to Fukushima Open Thread 2.]

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re post by: b, on 28 March 2011 at 4:27 AM said:

… added boric acid to the freshwater feed of unit 2. Such was NOT added to unit 1 and 3 freshwater feed….Why is there, 16 days after shut down, still need to suppress fission in unit 2?

How does that relate to short half life nucleotides in the water in the unit 2 turbine hall? Could the partial meltdown in no 2 have restarted some fission?

Hi b,

Primarily it’s being added as an overabundance of caution. Engineers and scientists are trained to always consider that almost anything, no matter how improbably, might be possible. They want to be absolutely certain (or as close to it as possible) that no matter how improbable, criticality can’t re-start.

As you probably know, once reactors are shut down, because it is uranium (and a small percentage of plutonium) there will always be a small percentage of fission occurring. So even tho it is very unlikely for criticality to occur, in a situation like this, if the coolant isn’t already carrying a large amount of boron, when you can, you add more.

I think if you go back thru the various reports you will find that they have added boron to each reactor at various times as the situation permitted.
MODERATOR
RD this is wandering into deep discussion probably more suited to the Fukushima Open Thread 2 and away from an up-date to the Fukushima situation. Blurred lines I know:)
but perhaps you should switch over and leave a note to that effect on this thread.

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Ok, so the entire urgent news release that bks posted (28 March 2011 at 2:31 PM) the start of, finished with all of one more sentence:

Chief Cabinet Secretary Yukio Edano told a news conference that the government believes that the meltdown was only temporary.

Now, some of the translation problems get pretty funny, like the ones saying that contaminated leg skins were laundered. But at least with those you know what was meant, even if the rather graphic gory picture they bring to mind is something totally different.

But in a case like this, one has to wonder just what the heck is going on. Is it just a translation fubar? Or does Edano not have the slightest understanding of what a meltdown is? Or is this just more speculation and a translation fubar & nothing more?

Sigh.

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re AFTERSHOCK posts:

harrywr2, on 28 March 2011 at 10:26 AM said: http://earthquake.usgs.gov/earthquakes/recenteqsww/Maps/10/145_40_eqs.php

I count seven Magnitude 6+

Thank you Harry! Mindblowing, isn’t it? I wonder how many of those were situated such that there was any significant ground shaking at the plants…

Joshua, on 28 March 2011 at 12:52 PM said: I have the M5+ shocks by day from 24 Mar and above 4.5 shocks from 27 Mar on plotted in google earth. I am not sure how to export the whole thing. I have a kmz from if that is good enough and people want it I will make a public link in dropbox for it and work to keep it updated. Let me know…

Hi Joshua, I’m not sure either – I confess I haven’t used google earth much and I’m not sure what programs can display kmz files. Maybe someone else here knows. Are yours in the Japanese rating scale, or MM or Richter?

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apart from the head scratching caused by the possibility of a temporary meltdown, whatever it could be, some lines on the Reuters “wrapup 3″linked by Rational Debate hit me (end of 2nd page):

“Japanese Prime Minister Naoto Kan has kept a low profile during the crisis, but may face awkward questions after Kyodo news agency said his visit to the region the day after the disaster delayed TEPCO’S response to the unfolding situation.

“The process to release the steam was delayed due to the premier’s visit,” because the power company feared Kan could be exposed to radiation, it quoted an unnamed government source as saying.”

could this be an additional reason for the delayed explosion in the 1 and 3 reactors? I mean, the need (real or just feared) to avoid steam releases during the gov’t member visit could have caused the over accumulation of hydrogen that led to the explosions on the second day after the quake?

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ah, sorry for not saying: the audio of the heli video is just the pilotvoice explaining what he’s flying over (like “this is the no. 2 reactor viewed from south”)
if you need I can do a partial translation.

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I’ve transfered my reply: Rational Debate, on 28 March 2011 at 4:12 PM to a post by: b, on 28 March 2011 at 4:27 AM over to the open 2 thread per Moderator request. (Thanks Moderator!)

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re post by BerGonella, on 28 March 2011 at 4:48 PM said:

ah, sorry for not saying: the audio of the heli video is just the pilotvoice explaining what he’s flying over (like “this is the no. 2 reactor viewed from south”) if you need I can do a partial translation.

Thanks BerGonella – I confess I can make out almost nothing from the video anyhow. If anyone thinks that they can where a translation would help pin it down, that would be of interest. I keep hoping to see a glimpse of a fuel pool or something, but sure can’t make one out. Remnants of an overhead crane I think, but that’s about it.

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This seems important and hopeful to me:

‘The high doses from the water come from the rapid decay of radionuclides with short half lives. This leads officials to presume the water comes from the reactor system rather than the used fuel pond where this decay would have taken place some time ago. At the same time, however, pressures in the reactors have not dropped, indicating no large-scale pipe break. The primary containments of unit 1 and 3 are thought intact, although damage is suspected at unit 2.’

http://www.world-nuclear-news.org/RS_Contaminated_pools_to_the_drained_2703111.html

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According to people who understand Japan language(and are in Japan atm), it was just reported live on TV that according to TEPCO, “radioactive water under unit2 is now out of it” (ie around unit 2?)
.

2 Rational Debate
Maybe you think I’m overreacting, but for last 14 days I frequently follow events, reading official statements and several forums. I’m tired of reading TEPCO saying “there is X, but no Y”
Then in a forum where professionals post I see “wtf if they report X, that means there is Y, but thay deny it”
1-2-3 days later, TEPCO says “a, yes, there is Y”

And yes, they should be running around with dosemeters. Every hour or so. And have a f***ing MAP with expected doses.
Technicians are NOT supposed to work with 1Sv/h beta on their legs without rubber boots.

Maybe TEPCO didn’t know these levels – which mean incompetence or too stretched resources (why? They should receive all the resources needed to handle situation, the faster the better).
Or (as was on several occasions during this crysis) they try to hide&deny.

I don;t think they are incompetent, I don’t believe they are stretched on resources now (tho they were in the beginning and someone must say why).
So, 1 possibility is left.
Make your choice.
MODERATOR
Chavv and RD – this conversation should be moved to Fukushima Open Thread 2. It is starting to bog down the up-date thread as it evolves beyond the up-date. Please re-submit to Fukushima Open Thread 2. Further comments like this may be deleted as we do not have the facility to move comments between threads.

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I’m not sure what the significance is, but TEPCO’s latest report notes:

– Previously, we have been injecting fresh water in to the reactor
utilizing fire pump, however, we have switched over to utilizing
temporary electrical pump from 6:31 pm on March 27th.

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‘Muto acknowledged it could take a long time to clean up the Fukushima complex.

“We cannot say at this time how many months or years it will take,” he said, insisting the main goal now is to keep the reactors cool.
Workers have been scrambling to remove the radioactive water from the four units and find a place to safely store it. Each unit may hold tens of thousands of gallons of radioactive water, said Minoru Ogoda of Japan’s Nuclear and Industrial Safety Agency, or NISA.

Safety agency officials had been hoping to pump the water into huge, partly empty tanks inside the reactor that are designed to hold condensed water.

Those tanks, though, turned out to be completely full, said NISA official Hidehiko Nishiyama.

Meanwhile, plans to use regular power to restart the cooling system hit a roadblock when it turned out that cables had to be laid through turbine buildings flooded with the contaminated water.

“The problem is that right now nobody can reach the turbine houses where key electrical work must be done,” Nishiyama said. “There is a possibility that we may have to give up on that plan.” ‘

http://www.katu.com/news/national/118735809.html

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Latest plant parameter data shows the temperature and pressure at reactor 1 continuing to rise:
[deleted link in Japanese. Please re-submit in English so evaluation can be properly made by commenters.]

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strongly contaminated water has been found in a overflow tunnel outside the reactor.

ps: i do not think that it creates confidence in nuclear energy, when any negative news need citations.
MODERATOR
Sod – both positive and negative news require citations on BNC . The Open Threads are the place for uncited opinion.

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Related, if not exactly on topic: I haven’t read everything here, so it’s possible this has been mentioned already, but there is some Finnish research about the longtime effects of nuclear fallout in populations, we have had some both from the Soviet Union bomb tests and from the Chernobyl accident (Finland also has pretty high natural background radiation levels in some areas, we have lots of granite). There are English versions of some reports on STUK (Radiation and Nuclear Safety Authority Finland) net pages, so this one might be of some interest to you:

http://www.stuk.fi/stuk/tiedotteet/2010/en_GB/news_607/

Short: There hasn’t been any increase in cancer.

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Rational Debate
I assume it is moment magnitude, whatever USGS is reporting I am just opening the kml files from USGS in GoogleEarth to add it to the map. Then changing the icon to give an indication of magnitude and changing the lable to give USGS reported magnitude and Japan local date.
MODERATOR
This discussion has moved to Fukushima Open Thread 2. Please cut and paste you comment there. Thank you.

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Can someone comment on the potential threat if the radioactive plutonium particles (by way of cooling water leaks or god forbid a meltdown) enters the water table? From what little I know about ground water, it can travel along countless cracks and fissures in the rocks for miles before it reaches larger reservoirs. It was one of the main unforeseen problems with the Yucca Mt dump site. Is this is a more dangerous threat of PU contamination to the environment than the air borne radiation dealt with thus far?
MODERATOR
This is the wrong thread for this type of discussion. Please move to Fukushima Open Thread 2.

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If there was any volatilisation of the material in the spent fuel pond, then one might expect minute traces of Pu in the soil surrounding the units at the plant site. Being a heavy metal means that it would not mobilse readily and would deposit very locally. Remember, Pu is present in all spent fuel, via the U-238 –> Pu-239 transmutation pathway. It is not something peculiar to MOX fuel. Also, I’ll have to do a post about Pu at some point soon. It’s a metal guys, not a demon.

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sidd…

Im not sure where the Ag-108 comes from, but the following document lists it, along with many other substances, on page 3, in relation to stainless steel control rods.

Click to access S08-06.pdf

As for I-134, are you getting reactors confused? It was unit 2 where they claimed to have found I-134 in the water, and where they later said they had made a mistake and removed I-134 from later results of both the original water sample, and a new one. The document you linked to was produced before this error was spotted, which is why I-134 is still listed for reactor 2.

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Mr. Elbows, I found this as a link at the bottom of

Click to access en20110328-1-1.pdf

dated the 28th. This may have been the original report but i see that the first column is marked Unit 1, 2nd time, sampled March 26th. I thought that Unit 1 was the one they sampled twice because of the doubt about the first sampling and measurement ?

sidd

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sidd, the link at the bottom of the document leads to a completely different pdf than the one you mentioned earlier. The pdf it links to has 4 columns of results, but they are all for reactor 2, not different reactors.

I think you got confused because they have also tested the water at units 1 & 3 twice, and they used the 2nd set of results from these when compiling the table that shows levels at all 4 locations.
MODERATOR
THis conversation is beoming unsuitable for this up-date thread and is starting to clog it up with overly technical discussion. Please move to Fukushima Open Thread 2.

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Re Earthquakes GoogleEarth File

Rational Debate

I hope this is a link to the Earthquakes from the last few days (5+ Since 24th 4.6+ Yesterday) These are from USGS. I also found KML files that show where all reactors are, the evacuation zone around Daiichi and a drawing of techtonic plates from USGS. No quakes since last night 2300 US East Time. If this is of use I will update it.

http://dl.dropbox.com/u/17774538/JapanEarthquakeInfo.kmz

@MODERATOR I can not check this link because the file is already loaded into my GoogleMaps. If it is broked delete it with my apologies.

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> harrywr2
> Not significantly different then normal ‘background’

Wrong. Comparable to the level from the fallout after some atmospheric nuclear test (which one, and when, not identified by TEPCO; I’d guess China’s).

Harry, this is a science blog. Not a debate blog.
Giving a partial summary of part of the information can mislead readers who don’t suspect you are debating; they may believe you’ve given an accurate report.

Please do better.

The “328e14.pdf” is Attachment 3 to this press release: http://www.tepco.co.jp/en/press/corp-com/release/11032812-e.html

Excerpt:
“… 2.Analysis Density of detected Pu-238, Pu-239 and Pu-240 are within the same level of the fallout
observed in Japan after the atmospheric nuclear test in the past. Activity ratio of Pu-238 detected in site field and solid waste storage against Pu-239 and Pu-240 are 2.0 and 0.94 respectively. They exceed activity ratio of 0.026 which resulted from the atmospheric nuclear test in the past, thus those Pus are considered to come from the recent incident.”
MODERATOR
Please move this conversation to Fukushima Open Thread 2.

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Well, THAT got garbled up somehow – a sentence of mine wound up in the TEPCO report rather than with my text. It’s corrected below, with the errant sentence in bold.

I’ve been having a wicked problem with the mouse-click-bar (whatever it’s called!) that is immediately below my touchpad sticking (e.g., no mouse, just touchpad & bar below it) – and it seems to be causing my computer to be acting a bit schizophrenic, jumping insertion points around, highlighting things when I don’t want them highlighted, even grabbing & moving them when I wasn’t even trying to select let alone move, launching links if I happen to hover or cross over them, click once to launch something and it appears 3+ times, or click once to close a tab, and multiple tabs get closed. Its driving me crazy.

The corrected post:

Barry & others re Plutonium.

Let’s not forget that Pu is also present from fallout. It seems pretty overblown for all the excitement, Kyodo report, etc., when it isn’t even passed along with the concentrations – which was equivalent to that already present in the soil from weapons testing apparently.

I haven’t double checked the attachment’s but do note that they are there if you would like to check the actual reported amounts yourselves.

http://www.tepco.co.jp/en/press/corp-com/release/11032812-e.html

Press Release (Mar 28,2011)
Detection of radioactive material in the soil in Fukushima Daiichi Nuclear Power Station

On March 28th 2011, as part of monitoring activity of the surrounding
environment, we conducted analysis of plutonium contained in the soil
collected on March 21st and 22nd at the 5 spots in Fukushima Daiichi
Nuclear Power Station. As a result, plutonium 238, 239 and 240 were
detected as shown in the attachment.

We will continue the radionuclide analysis contained in the soil.

‹Results of the analysis›
-Plutonium was detected in the soil of Fukushima Daiichi Nuclear Power
Station.
-The density of detected plutonium is equivalent to the fallout observed
in Japan when the atmospheric nuclear test was conducted in the past.
-The detected plutonium from two samples out of five may be the direct
result of the recent incident, considering their activity ratio of the
plutonium isotopes.
-The density of detected plutonium is equivalent to the density in the
soil under normal environmental conditions and therefore poses no major
impact on human health. TEPCO strengthens environment monitoring inside
the station and surrounding areas.
-We will conduct analysis of the three additional soil samples.

attachment1:Result of Pu measurement in the soil in Fukushima Daiichi
Nuclear Power Plant(PDF 80.9KB)
attachment2:Fukushima Daiichi Nuclear Power Station Sampling Spots of Soil
(PDF 112KB)
attachment3:Fukushima Daiichi Nuclear Power Station Regular Sampling Spots
of Soil(PDF 135KB)

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@ Sidd, Steve Elbows, anyone else looking at the various detected isotopes, I’ve posted info regarding some possible sources for isotopes you might not expect to see over on the open 2 thread.

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This is a JAIF report – most of it appears to be stuff they’ve collected from NHK news, and only a few tidbits perhaps that haven’t been posted here. There is more to the report, but it seemed duplicative to me so here’s the gist of it below.

Sounds to me as if all of the water they’ve been pumping into SFP’s and possibly RV has finally overwhelmed the site building’s radwaste sumps and other fire etc. drainage tanks/sumps, so it is starting to pool now in whatever low spots it can find.

Click to access ENGNEWS01_1301377967P.pdf

●TEPCO faces challenge in cooling reactor
The Nuclear and Industrial Safety Agency said on Monday that TEPCO has to
strike a balance between injecting cooling water into the reactors and
preventing radioactive water from seeping out.
On Monday, the power company detected radiation of more than 1,000
millisieverts per hour on the surface of puddles in the No. 2 reactor’s turbine
building and in a trench outside the building.
The concrete trench stretches toward the coast but does not connect to the sea.
Puddles of water were also found in the trenches of the No.1 and No.3
reactors.
The No.1 reactor’s trench will overflow if the water rises by 10 centimeters.
TEPCO has blocked the trench outlet with sandbags and concrete to prevent
the water from reaching the ocean.
The water in the trenches of the No.2 and No.3 reactors is reportedly 1 meter
from overflowing.

TEPCO said it hopes to swiftly find a way to remove the water from the
trenches.
On Monday, The power company scaled back its operation to cool the No. 2
reactor, injecting 7 tons per hour, reduced from 16. The reactor’s temperature
rose by more than 20 degrees Celsius.
Tuesday, March 29, 2011 08:03 +0900 (JST)

●Radioactive water in external tunnels
The operator of the damaged nuclear power plant in Fukushima, northeastern
Japan, has reported that very high levels of radiation have been observed in water
in a trench just outside the turbine building for one of the reactors.
Tokyo Electric Power Company announced on Monday that a puddle of water
was found in a trench outside the No. 2 reactor turbine building at the Fukushima
Daiichi nuclear plant on Sunday afternoon. It said the radiation reading on the
puddle’s surface indicated more than 1,000 millisieverts per hour.
The concrete trench is 4 meters high and 3 meters wide and houses power cables
and pipes. It is located in the compound of the plant but outside the radiation
control area.
TEPCO says the trench extends 76 meters toward the sea but does not reach the
sea, and that the contaminated water was not flowing into the sea.
TEPCO says it is trying to find out how the contaminated water came to be in the
trench.
Radiation levels of more than 1,000 millisieverts per hour were recorded on
Sunday in a puddle of water in the basement of the No. 2 reactor turbine building.
Puddles of water were also found in the trenches outside the No. 1 and No. 3
reactors. TEPCO reported 0.4 millisieverts of radiation on the surface of the
puddle in the No. 1 reactor’s trench. But it said it failed to measure the No. 3
reactor’s trench because it was covered with debris.
TEPCO says it had no intention of concealing data regarding the high level of
radiation detected on Sunday outside a turbine building at its Fukushima Daiichi
nuclear plant.
TEPCO Vice President Sakae Muto said at a news conference on Monday that he
only received the report from the plant workers earlier in the day.
The plant operator has revealed that it found water in a covered tunnel outside
the turbine building of the number 2 reactor, and that radiation of more than
1,000 millisieverts per hour was detected in the water.
Muto said the company has made this public and instructed the plant workers to
quickly take steps to dispose of the water.
Asked by reporters if TEPCO was concealing information, Muto said the
company has no intention of doing so.
He also said every day is full of events, and that TEPCO will quickly share
information of high importance so that it can swiftly consider countermeasures.
Vice President Muto added that the plant operator will confirm the flow of
information and have it thoroughly implemented in order to avoid
misunderstandings.

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I imagine most of you have seen that the three workers who were exposed to the high dose rate water were discharged from the hospital – I post this only because while I’ve seen statements along the lines of all could walk just fine and so on, this is the first I’ve seen that was as clean cut:

http://www.world-nuclear-news.org/RS_Contaminated_pools_to_the_drained_2703111.html

…The three workers have now been discharged from hospital. Tepco said they would be counselled and their future wellbeing monitored closely, but that they showed no signs of ill effects….

I’ve also seen a report that the dose estimated by examination – which is a miserable way to estimate dose, by the way – was reduced to 2-3 Sv to the skin/legs (I’m sorry, didn’t note the link and ran across it some time ago).

That dose wouldn’t be expected to cause more than transient erythema – no burns. Other reports were that they worked in the areas for 3 hours, but stood in the water less than 1 hr (then we’d have to add the time until they came out and were decontaminated, however). Regardless, it is sounding as if it is unlikely that they will wind up with beta burns. Similarly, with chest level dosimeters reading 170-180 mSv, there shouldn’t be any health effects either. That said, if the dose calcs are off and significantly underestimated, there could be consequences – it just is sounding less and less likely.

What is odd, however, is that on the last few TEPCO reports, the total number of workers exposed to over 100 mSv jumped from 17 to 19, with no explanation of where the other two came from… of course, we don’t have details on each and everyone anyhow, so perhaps that’s not surprising.

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from http://www3.nhk.or.jp/daily/english/29_22.html

More water pumped into No 1 Fukushima reactor

Tokyo Electric Power Company has begun pouring more fresh water into the No.1 reactor at the Fukushima Daiichi nuclear power plant to cool it down.

TEPCO says the surface temperature of the No.1 reactor rose from 212.8 degrees Celsius as of 6 AM on Monday to 329.3 degrees 20 hours later.

It blames heat generated by the reactor’s nuclear fuel. The reactor is designed to operate up to 302 degrees under normal conditions.

The power company raised the volume of water into the reactor from 113 liters a minute to 141 liters at 8 PM on Monday. As a result, it says, the reactor’s temperature fell to 323.3 degrees as of 6 AM on Tuesday.

TEPCO says it will continue closely monitoring the reactor while fine-tuning water volume.

Tuesday, March 29, 2011 14:36 +0900 (JST)

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hoping to be useful, I link here some graphics made by an italian resident in Tokyo, based on the data supplied by Japan authorities.
they are continuously updated, so please check the blog’s homepage http://giappopazzie.blogspot.com/ or the page dedicate to the updates http://giappopazzie.blogspot.com/2011/03/comunicazione-e-aggiornamenti-upd-3003.html

after some days dedicate to the central only, they widened the range, up to obtain a graph for the central and a graph or each prefecture interested by the event. scrolling the update page you can check everyone, and zoom it by clicking on it.
I’m sorry all the explanations are in italian, but they are not o difficult to understand, and anyhow the figures are universal

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‘Some plutonium found in soil on the grounds of the Fukushima Daiichi nuclear power plant may have come from its earthquake-damaged reactors, but it poses no human health risk, the plant’s owners reported Monday.

The element was found in soil samples taken March 21-22 from five locations around the plant, the Tokyo Electric Power Company told CNN late Monday. The company said it was equivalent to the amounts that fell on Japan following aboveground nuclear weapons tests by other countries in past decades.

“It is not a health risk to humans,” the company said. But it added, “Just in case, TEPCO will increase the monitoring of the nuclear plant grounds and the surrounding environment.”

Plutonium is a byproduct of nuclear reactions that is also part of the fuel mix at the plant’s No. 3 reactor. It can be a serious health hazard if inhaled or ingested, but external exposure poses little health risk, according to the U.S. Environmental Protection Agency.’

http://edition.cnn.com/2011/WORLD/asiapcf/03/28/japan.nuclear.plutonium/index.html?hpt=T2

In the TV broadcast they expanded this to say that they do not know as yet which reactor it is from, but it is clear that it is from one of their reactors not old weapon’s test residuals due to the composition.

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This is an old report. I was going to post it yesterday, but my computer crashed and I took that as a sign to take a break from all this. NHK reports:

“The plant’s operator, Tokyo Electric Power Company, raised water pumping power on Sunday to cool the No. 2 reactor in a stable manner. On Monday, the company cut back on the amount of injected water.

The move followed the Nuclear Safety Commission’s announcement that highly radioactive substances detected in puddles of water in the basement of the reactor’s turbine building may have come directly from the vessel containing the reactor.

16 tons of water was being injected into the reactor every hour but TEPCO now says it wants to reduce the amount to 7 tons. This would be enough to replace the amount that is evaporating.”

http://www3.nhk.or.jp/daily/english/28_h28.html

I initially thought that seemed like way too much water needed to evaporate each hour to cool the reactor. 7 metric tons of water with heat of vaporization of 2257 kJ/kg is 15,799 MJ/hr or 4.4MW of power needing to be cooled. From the following link at MITNSE I find the projected decay heat for Unit 2 (and 3) to be 10.5MW (3/20/11) and 8.8MW (4/1/11) so 7 tons is actually on the low side. Even a year after this event they will have to be removing 5MW of heat. (3/11/12, last table entry)

http://mitnse.com/2011/03/16/what-is-decay-heat/

If they are injecting that much water, I would think that some is leaking out directly or going into the suppression pool which would fill up and the water would have to go somewhere eventually. Actually the steam would go there anyway. Now if they are circulating that water to heat exchangers/condensers that would be a different matter. Anyone seen more direct information?

During the initial response to this situation, all the information I’ve seen indicates that they were not circulating water, but injecting it and blowing off the steam to cool the reactor. That is a lot of water they must have and may still be injecting. Where did it all go? Could they have sucked some of it back out of the suppression pool and primary containment and reinjected it? This would be very radioactive water so I don’t think that is possible. We know where some of the water has gone. I would think that the vast majority must have been flushed out to sea as I can’t see them storing these large amounts on site.

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Surely the water must be getting into the sea, or the levels of radioactivity there would not have risen so much?

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10 tons of water for 24hrs/day*18 days is 4320 tons of water evaporated/injected. That is 4320 cubic meters of water. Or if they have an area of 40×40 meters to store it in that would be a depth of 2.7 meters. So I guess it is possible to store it on site. I’ll have to look more closely at the reactors/turbine buildings. I believe they are now cooling the reactor water so these numbers are probably on the high side. Still seems like a big problem to deal with. This is speculating to try to understand what is going on. I would like to hear other peoples thoughts on the matter.

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Just posting this to help with your calculations.

It seems there may be south to north drainage at the plant.

—
Japan Times

(snip) monitoring data collected at 2:05 p.m. Sunday some 30 meters north of the drain outlets for the No. 5 and 6 reactor buildings detected radioactive iodine-131 levels in the seawater 1,150 times above the government standard.

The level from the same monitoring place was 202 times at 8:50 a.m. Sunday and 314 times at 2:50 p.m. Saturday.

Previously, the higher level of iodine-131 was detected at the south side. A reading of 1,250 times above the standard was detected at 8:30 a.m. Friday about 330 meters south of the drain outlets for the No. 1 and 4 reactor buildings, and it was 1,850 times at 2:30 p.m. on Saturday.

But the level had declined in the latest data collected, at 1:50 p.m. Sunday, to some 250 times above the standard.

Asked what the rising figure in the north and the decrease in the south indicates, “there are various possibilities, and it is possible that the contamination flowed from south to north,” a Tepco official said during a press briefing around noon.

http://search.japantimes.co.jp/cgi-bin/nn20110329a1.html

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Question for MODERATOR — you’ve said several times “this conversation” should be moved to the open thread — but haven’t been explicit about which “this” you mean.

Looking back over the requests I think you mean discussion of the radioactivity found outside the plant?

(Doesn’t make sense to me but it’s those posts you’ve commented in each time). Can you be explicit? If that’s what you think needs to be out of here, may I suggest a specific thread?

It’d be a shame to dilute the few facts we’re accumulating into that, er, highly-opinion-rich discussion in the open thread
MODERATOR
Hank – It is a difficult one. I will be more specific in future. Basically what we are trying to avoid is that the threads, particularly the up-date threads, don’t get bogged down, with too much technical information as these threads are used by a lot of people wanting a user friendly up-date of the current situation. A specific thread for each topic would be difficult so Barry has suggested that you make sure your comment is prefaced by the subject in bold letters so those following can easily pick it out from the rest of the Open Thread.

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@David Martin

Yes I agree water is getting into the sea. I’m looking for the reason that they may have had to deliberately released that water, as they couldn’t handle the volumes involved. No where to store it, especially since the water is radioactive and they need to work there and so can’t let too much accumulate. They have said they are sending some of the water that was in the turbine building to the condensors. There was a report saying the condensors in one of the units may be full, but I can’t find that right now. So much information, a lot of it uncertain, it is hard to even know how close they are to getting control of the situation. Thought they were last week, but they have had some serious setbacks since then. As I said at that time, this is a dynamic situation. It will continue to surprise us. I don’t want to leave the impression everything is getting worse. Outside the immediate area and a few hotspots outside that, the radiation readings in the rest of Japan are low. Tokyo has had minor blips up in radiation levels and I-131 briefly being above regulartory limits for infants under one. Here are a few links to various monitoring sites in the Tokyo area.

http://ftp.jaist.ac.jp/pub/emergency/monitoring.tokyo-eiken.go.jp/monitoring/past_data.html
http://rcwww.kek.jp/norm/index-e.html
http://park30.wakwak.com/~weather/geiger_index.html

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@Shelby

I find information in the form of x number of times above the regulatory limit as particularly useless. No one is going to swim in this water let alone drink it. The only and especially long term effect is bioaccumulation in sea food. That is a concern and will have to be monitored for months to years. The measurements will be useful in determining the amount of radiation that has been released into the water, but aren’t that useful for any immediate health concerns except for maybe the people collecting the samples.

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dumb question: if the water is coming from the reactors, and is outside the turbine buildings, does that imply that the damage is in the turbine buildings and may have been due to the earthquake? possibly damaging the pipes between the reactor and the turbine, so when water was injected it was flowing into the turbine room(s)? this may have been covered before, my apologies, if it has let me know and I will search thru the thread for it.

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@Shelby

I’m sure there are people modeling the currents, tides, and wave action at the site. This is way beyond my level of expertise, so I could not even comment on what the different readings and change means.

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William Fairholm, on 30 March 2011 at 1:47 AM said:

@Shelby

I find information in the form of x number of times above the regulatory limit as particularly useless. No one is going to swim in this water let alone drink it. The only and especially long term effect is bioaccumulation in sea food. That is a concern and will have to be monitored for months to years. The measurements will be useful in determining the amount of radiation that has been released into the water, but aren’t that useful for any immediate health concerns except for maybe the people collecting the samples.

—-

I just thought drainage direction might help explain radiation reading spikes in one area while radiation levels subside in other areas. I wasn’t making a statement, I was providing a possible reason for fluctuations in radioactivity.

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@schla

I am guessing that the water was dumped in the turbine building when they started to circulate water out of the reactor to cool the water. It hadn’t happened before that I know of. This would imply a leak somewhere in the turbine building side of the circulatory system, but I can’t recall seeing a explaination of how the radioactive water got there. They may not know for sure. Pumps, valves and heat exchangers would be places I would suspect.

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189.

@schla

I am guessing that the water was dumped in the turbine building when they started to circulate water out of the reactor to cool the water. It hadn’t happened before that I know of. This would imply a leak somewhere in the turbine building side of the circulatory system, but I can’t recall seeing a explaination of how the radioactive water got there. They may not know for sure. Pumps, valves and heat exchangers would be places I would suspect.

—-

I would think seawater is especially damaging to valves?

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There has been a lot of water spayed/injected into the SFPs. This water has not all gotten into SFP. There may be leaks there as well. They will have to have dealt with this water as well.
Water has evaporated from the SFPs, and “steam” has been released from the reactors so this would reduce the amount of water they would have to deal with. This is getting fairly complicated, so I don’t think any firm conclusions can be made, but it does give an indication of the volumes of water Tepco are dealing with.

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William Fairholm, on 30 March 2011 at 12:56 AM said:

10 tons of water …so these numbers are probably on the high side

Current pump rates

Click to access en20110329-7-3.pdf

Unit 1 – 141 litres/min = 8.4 cubic meters per hour
Unit 2 – 117 litres/min = 7 cubic meters per hour
Unit 3 – 200 litres/min = 12 cubic meters per hour

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@William Fairholm: it was my understanding that the SFP’s can’t be the source of all that water due to the radioactive properties of the water (fission by products). yes, at face value it appears to be the logical answer. I am wondering if the lack of adequate instrumentation on the reactors due to lack of control room power has led the TEPCO engineers astray as to what is actually happening. I thought the assumption of pumping in the seawater into the reactors was that the water was turning to steam and being vented to atmosphere or somehow going thru the suppression system? otherwise, what goes in must come out… which means water pumped in is coming out, perhaps in the turbine rooms…

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Well, the reactors are shot anyhow — they could start incorporating some of the different colors of fluorescent dye in the water going into variousthat could show them where the leaks are happening.

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@schla
I wasn’t trying to say that the water in the turbine building was from the spraying into the SFPs, just that they have added a lot of water to the SFPs. The SFPs are at the top of the reactors. Water from the spraying and/or leaking is probably at the bottom of the reactor building. They are now injecting water into SFP 3, if I remember correctly, and are using a concrete pump truck to more precisely add water to SFP 4. So missing isn’t as much of a problem now. They may be leaking, but I’ve seen no definite information on that matter, just a credible possible source for a leak (the air filled seals of the gate at the top of the pool). That would still leave water over the spent fuel, but evaporation could then have exposed the fuel. Cracks in the pools and sloshing of water out of the pools during the earthquake have also been mentioned as ways water could have been lost to expose the spent fuel. This is all getting a bit too speculative, and the spent fuel ponds have been dealt with before. I don’t think I have anything more to add. Don’t want to clog up this thread with just one subject. I’ll look back in a few hours, but I’ve got other things to do.

P.S. The SFPs of Units 1 & 2, appear to be fine.

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http://www.guardian.co.uk/world/2011/mar/29/japan-lost-race-save-nuclear-reactor

…. Lahey, who was head of safety research for boiling-water reactors at General Electric when the company installed the units at the plant, said his analysis of radiation levels suggested these attempts had failed at reactor two.

He said at least part of the molten core, which includes melted fuel rods and zirconium alloy cladding, seemed to have sunk through the steel “lower head” of the pressure vessel and on to the concrete floor below.

“The indications we have, from the reactor to radiation readings and the materials they are seeing, suggest that the core has melted through the bottom of the pressure vessel in unit two, and at least some of it is down on the floor of the drywell,” Lahey said. “I hope I am wrong, but that is certainly what the evidence is pointing towards.”

The major concern when molten fuel breaches a containment vessel is that it will react with the concrete floor of the drywell, releasing radioactive gases into the surrounding area. At Fukushima, the drywell has been flooded with seawater, which will cool any molten fuel that escapes from the reactor and reduce the amount of radioactive gas released.

Lahey said: “It won’t come out as one big glob; it’ll come out like lava, and that is good because it’s easier to cool.”

The drywell is surrounded by a secondary steel-and-concrete structure designed to keep radioactive material from escaping into the environment. But an earlier hydrogen explosion at the reactor may have damaged this.

“The reason we are concerned is that they are detecting water outside the containment area that is highly radioactive and it can only have come from the reactor core,” Lahey added. “It’s not going to be anything like Chernobyl, where it went up with a big fire and steam explosion, but it’s not going to be good news for the environment.” (continued online)

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Regarding the guardian article I posted – Lahey is the expert, but I have to wonder if he’s seen all the data. I just don’t see how you get a bottom RPV temp of 77 C, and drywell pressure at atmospheric or slightly above, if you’ve got corium/slag in the process of melting thru the bottom RPV. Now, obviously that temp may be wrong, but it does appear to change some (e.g., its not just fixed at 77) – So… how could you possibly be melting thru, and have interaction with both water in the drywell and the drywell concrete, and still get these temps & pressures?

doesn’t seem to add up.

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re post by: Hank Roberts, on 30 March 2011 at 3:53 AM

Hank, it’s an intriguing idea, but one that I suspect isn’t practical. I mean, we’re talking massive amounts of water here. So, how do you get the dye in – and not just in, but either fast enuf or slow enuf that it would be useful. Plus, I would think it would take absolutely massive amounts of dye. Unless perhaps you’re aware of some sort of dye that would still be visible/detectable if added in relatively small amounts vs. the tons and tons of water involved here with both the reactors and the SFPs?

Plus, it’d have to be a dye or tracer that wasn’t degraded by the heat, temps, rad levels, etc., involved.

Then you also would have to know that it wouldn’t add to any chemistry problems. I mean, you sure don’t want to worsen any corrosion at this point, or cause seal/valve failures, or even increase the risks of problems like that – NOT because of trying to save any value or recovery capabilities, they’ve given up on that long ago I’m certain – but because you could inadvertently create worse problems than they’ve already got. I would think that unless something had a really good chance of telling you something you didn’t already know, then you’d really want to avoid adding anything to the systems.

They’re already so mucked up as it is that I understand the tendency to think “what the heck, what could it hurt?” but don’t think that’s the prudent course of action. Gotta say that I’m close to on the fence in that regard myself tho, but would trust the judgment of any good reactor systems person or nuke plant water chemistry type.

Plus, there are a huge number of possible pathways (including backed up sumps/drains, resins, tanks) – many of which might be able to cross paths too. In other words, I’m not sure you’d even be able to have any certainty about source even if you did see some of the dye. You know, did it come from a leak, or from steam condensation running down into the sump somewhere? That sort of question.

It sure as heck would be nice if they had some good tracer that could be used in situations like this, tho, wouldn’t it?

Seems like trying to come up with something of this nature would be an ideal project for a grad student – tho of course typically funding is still an issue there also, someone would probably have to approve a grant for it.

Note, there are some products for leak detection use – but I’ve no idea if any of them would be suitable/useful/safe for this sort of situation. Just google something like:

(tracer OR dye) leak detection “nuclear power”

You’d think that if any of them were suitable – or even if a company thought they MIGHT be, that the company would be falling all over themselves to offer it to TEPCO right now. Talk about some awfully good press if your product helped out in a major emergency situation like this…. so I’ve got to think that either there’s nothing available out there – or talks are in progress right now. {VBG}
MODERATOR
RD – this is getting off-topic and becoming very detailed – more suited to Open Thread. Please continue the conversation there. I have advised others of this too.Thank you.]

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Gawd what I wouldn’t give for some decently concise tables and charts of normal operating ranges and for the days and initial weeks post scram (or even just post shutdown, although the utility is lost very quickly there, since the cooling situation is so radically different) for just some of the basic operating parameters. Things like:

Reactor core & drywell & suppression pool & torus etc., temps, pressures, CAMS or other radiation monitoring devices. Including for any areas/rooms immediately adjacent.
Plus typical exposure rates & types, and typical isotopic sampling data (both airborne & liquid) for the ‘worst’ areas, including things like radwaste sumps/resins/holdup tanks, and so on.

Including for SFP liquid systems.
MODERATOR
Please move this topic to the Open Thread. Thank you.

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