Categories
GR Hot News Nuclear

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 Please switch to using this post for comments on the latest status reports and news to  hand (the old one is now out of date).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”

Tokyo Electric Power Co. acknowledged for the first time possible damage to core pressure containers at the crippled Fukushima nuclear plant–the last line of defense in preventing radioactive materials from spewing out.

TEPCO officials told reporters Monday morning that despite the continuous pumping in of water to cool down the No. 1, No. 2 and No. 3 reactor cores, water levels were not rising as expected, meaning the pressure containers may not be completely sealed off.

The water, which is believed to be mixing with radioactive materials from the fuel rods within, is likely leaking from the pressure containers, they said.

http://www.asahi.com/english/TKY201103280144.html

Like

oops. I might have screwed that last post up…

photo of one of the Browns Ferry BWR’s in construction. looks like the metal shell of the containment is INSIDE the concrete portion?

Like

me thinks the reason we can’t seem to get consistent data is that they are not getting alot of it until they get the power back on to the control rooms?

Like

@ Rational Debate 7:29 PM

I read the Guardian article and Lahey did not specify the data that led him to his conclusion. I am not sure if he has more data than what’s available to the posters on this thread.

I looked to see if I could find an article by Lahey that it is quoting from. I could not find one.

That being the case, I trust the more expert posters on this site.

Also found the following:

http://www.physicsforums.com/showthread.php?p=3217685

Originally Posted by Cire T 1:51 PM (EST?)
Richard Lahey is wildly speculating,

A few points which I believe are correct would tend to disprove his assertion.

1. History has shown via three mile island that its very difficult to melt through a reactor vessel. In the case of three mile island 70% of the core slagged to the bottom of the reactor vessel and heated it to the point where the entire vessel was glowing red. In that case only 5/8″ of inch out of 9″ was ablated.

2. A reactor pressure vessel is a massive heat sink. I believe the drywell on both reactor 1 and 2 where flooded early on in the process; providing addition temperature relief. This doesn’t include the water that has been injected since the start of the accident.

3. In three mile island the molten corium destroyed the temperature probes that measure the reactor pressure vessel, which is expected when you heat the sensors to this level. The temperature sensors are still functioning at the bottom of the reactor vessel on Unit 2. If the corium melted through the reactor vessel we would not have temperature data from the bottom of the reactor. I have yet to see a temperature measurement for the bottom of any of the reactor pressure vessels that comes anywhere near the melting point of steel.

4. Three mile islands coolant loss event occurred much earlier in the reactor shutdown process then did at Fukushima. This implies the fuel rods at three mile island suffered exponentially higher heat loads then the core at Fukushima.

finally, Richard Lahey states “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…”

What indications from the reactor? The radiation readings can be explained by the known damage suffered to the fuel storage pools.

Just my thoughts on the subject. I reserve the right to be mistaken.

Comment on above posted by NUENG T 2:13 PM (EST?)

TMI-2 was a PWR. Damage scenarios for fuel in a PWR begin at the Onset of Nucleate Boiling (ONB). A BWR doesn’t make any power until boiling occurs. They are concerned with a departure form Nucleate Boiling or dryout. A PWR may be closer to its limits, but anytime water level drops below the top of active fuel the fuel heatup is rapid and leads to damage in a very short time.

Unlike Fukushima TMI makeup water was blocked at the beginning of the event. Fukushima reactors probably used RCIC as long as they had steam and battery power. That could have delayed the onset of damage for several hours, depending on how they controlled the event. Once the reactor depressurized or the suppression pool reached its temperature limit, they were forced to vent containment to keep it below its limits, without having any makeup available for the RPV water level. That is the point where heatup and damage began.

TMI-2 was able to restore flow in the vessel and halt the meltdown before it reached significant damage to the reactor vessel. I amm not sure they have reached that point yet in Japan, so the reactor vessel could still be at risk. They have performed containment flooding, from the updates I have read, so that increases the heat sink for the reactor vessel.

If the vessel had been breached by corium melt-through it would likely result in a massive steam explosion due to the flooded containment. I haven’t seen evidence of that yet. Further at that point you would start to see different isotopes due to interaction with concrete.
MODERATOR
Please move over to Open Thread as this conversation is becoming long-winded and technical and clogging the thread which is supposed to be an update of the situation, in particular, for the general public. Others have been advised to do the same.

Like

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?

Look up Uranine, rather potent. This takes about 18kg:

Like

oops, didn’t see the embedding coming. offtopic yes, but it would also be time for a new update post..
MODERATOR
You might want to re-post your last video. It is off-topic there and it will probably not be seen because of that. Fukushima Open Thread 2 would be a good place.

Like

NHK live TV http://wwitv.com/tv_channels/6810.htm had an interview going on with someone explaining the situation both onsite & offsite. He just mentioned that the 3 (2?) worker’s who stepped in water during in the turbine building basement – the ones who were contaminated – didn’t realize the water was there before stepping in it, because they’re working in the dark w/ flashlights (!!).

Which frankly would explain a lot. e.g., how a puddle could have been all too easily missed on pre-work rad survey’s & why the workers would have worked in water to begin with. It’s far easier to understand a decision by non-rad workers espec if not typical nuke plant workers – and I have no idea if these particular workers always worked nukes or never did – for them to continue working in water after accidentally plowing into it when you have had to go to hassle of getting into anti-c’s and know the hassle/time it takes to get out of them and go thru contamination checks etc.

I guess I had been assuming that they must at least have portable generators running to provide lighting where needed. It’s far easier to understand how generators may not be able to be hooked into plant instrumentation or equipment, than that they don’t even have anything in the way of significant portable lights where it is really needed. Perhaps that was stupid on my part, since multiple reports have noted control room work being done by flashlight – but even there I had been thinking that flashlights were probably only needed to read and that they might be keeping it closed up to minimize contamination – e.g., not having doors open for electrical extension cords… Shoot, for that matter, however, while it’s not needed now that they do have lights on in control rooms, before that couldn’t they at least have gotten some electrical camping lanterns or something? Although these days that may not be any better than decent LED flashlights, which can be outrageously bright, and have flexible heads and base support so you can set them down and still use them…

I KNOW that the situation throughout Japan is nasty in terms of needing emergency equipment for all of the shelters and so on, and generators must be at a premium. Even so, I have a very hard time imagining that they don’t have as many as they need so there is at least some portable flood/room lighting for work where it’s needed.

Maybe I’m making far more out of this than is reasonable because that report could have been in error… but good lord, if they really are doing tunnel/trench & basement or enclosed room work with nothing more than flashlights??? Unless they do have some super-whamo-dyne LED’s, but even then I would have thought it would be far better and preferable for flood lighting to be available.

Are portable generators THAT scarce that even a nuclear crisis can’t get them? Or is it problems getting fuel for the generators (I find that even harder to believe). Or ??

Like

Also from NHK live, France is sending experts to help deal with deconning the high level water. 2 of those have already arrived and are in discussions with TEPCO. The others are to leave France soon.

They’re also saying that they don’t think the unit 1 trench is getting any water/radioactivity from the unit 1 basement water – so they’re going to verify. If unit 1 trench water is clean, they’ll probably at least initially drain it to the ocean.

Like

‘The core at reactor two of the Fukushima plant may have melted on to a concrete floor, according to experts, running the risk of radioactive gases being released into the surrounding area.

Richard Lahey, who was a head of reactor safety research at General Electric when the company installed the units at Fukushima, said the workers, who have been pumping water into the three reactors in an attempt to keep the fuel rods from melting, appeared to have “lost the race” to save the reactor.

“The indications we have … 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,” he told a newspaper.

“I hope I am wrong, but that is certainly what the evidence is pointing towards.” ‘

http://www.telegraph.co.uk/news/worldnews/asia/japan/8414554/Japan-nuclear-crisis-workers-losing-race-to-save-reactor.html

This is the first I have heard of this, but the source is quite credible.
One hopes not.

Like

re post by: Leo Hansen, on 30 March 2011 at 8:51 AM

Thanks for posting that Leo. I started reading that forum a day or two ago, but it’s rolling along fast and I’m a number of pages behind.

I agree with the points mentioned, however. Well, I’m not sure that if the RPV had totally boiled dry and then breached that it would necessarily have been rapid enough to cause a steam explosion, let alone a massive one – but heck if I know if it is possible to get a very small hole that allows corium to dribble thru, or if by that point you would get the RPV bottom just dropping out. More of a theoretical issue than anything else, as I believe that the other points mentioned in my post and that more detailed one, make it really unlikely that there was any melt thru anyhow. Sure would be interesting to know just what data Lahey was coming from tho, wouldn’t it? A corium melt thru RPV just doesn’t fit in too many different ways tho, it seems to me.

Of course, no way to know for sure just what we’ll find long after this is all over. No one expected TMI to be 40% slag on the RPV bottom either. I’d be VASTLY more surprised to find that any of the Fukushima Dai-ichi units have even gotten any distance into the RPV floor tho, than I was by the TMI melt.

Like

re post by: Hank Roberts, on 30 March 2011 at 8:51 AM

Hank, I just skimmed the article you linked, but don’t see anything there that would indicate tracers/dyes have to be installed up front. They’re selling a very specific system to help with day to day plant control – a totally different beast than the idea of whether something might be added now to Fukushima to help trace major leaks or at least pin down if its from reactor v SFP’s.

If we discuss this further, we probably ought to take it to the open thread 2… so if you want to do that, just post here that you’ve moved over or posted something there on this issue, and I’ll go find it.

Like

BARRY or MODERATORS – a request for you purty please.

Could we have an open thread for discussing technical issues specific to Fukushima (e.g., rad levels, analyses issues, dye’s/tracers, etc), and a separate one for the philosophical issues (e.g., LNT v threshold, nuke safety in general, nukes v other electrical power generation sources, nuke insurance issues, stuff like that)?

It would really make following BOTH threads far easier. You probably know I’ve posted on both tech & philo. issues, and even so, I would find it far easier to have them separated out so we keep the Fukushima technical debates separate from the Nuke/Electrical Generation Philosophy types of debates.

Plus, I suspect there are some folks who are far more interested in reading just one or just the other – so they’d be saved from having to wade thru a lot posts they’re really not interested in.

Thanks so much for considering this!

p.s., would all of you beg, plead, threaten {VBG} wordpress for the ability to toggle easily and at will between a chronological view (as we’ve got here) and a threaded view? BOTH have substantial advantages AND substantial advantages, and being able to flip between them super fast really really helps. I would think it would be easy for them to add this feature (yahoo groups has had something like this for at least 5+ years now). So they just need blog owners especially, and maybe any of us also, to plague them like the devil for it….
MODERATOR
I’ll have to pass that one on to Barry for resolution. As I understand it, the WordPress version we have is not capable of some useful add-on options but the other version can crash during periods of high volume traffic.

Like

Rational Debate — re: technical open thread + philosophical open thread — yes, I think that’s a good idea.

With WordPress at present, the blog owner must choose whether to have all threads either chronological or threaded. So the options are limited.

Like

re post by: sidd, on 30 March 2011 at 9:20 AM

Sidd, actually, what I was meaning was real and/or theoretical data for healthy BWR’s, the more similar to the Fukushima reactor builds the better (e.g., Mark-1 containment, etc., but heck, at this point, I’d take ANY BWR data!).

Even so, thank you for posting that link. It is nice/convenient to see all of the Fukushima data on a single page per unit that way.
MODERATOR
RD – please transfer this conversation to Open Thread as it is off-topic here. I have advised others of the same. I got started late today and have only just caught up from last night so I have let comments, if long, stand in their original threads. However, from here for the rest of today I will have to delete and ask for a re-post. The Fukushima Status up-date thread should be for that only and if discussions over technical issues etc evolove and become complexthey need to move to the Open Thread so as not to clog this thread and make it difficult to read. Thank you.

I would just dearly love to have data to compare it to – if you work at a plant, it’s fairly easy to get your hands on reference data (even if its just your own plant’s operational records). I haven’t found a good source online tho (confession, I’ve looked a little, but not spent a huge amount of time looking yet)

Like

@Rational Debate

Just a reminder that there were specific reports of a complete dry up of the #2 RPV on and around March 15-16, where the Jaif report indicates the “water level of the pressure vessel” is “recovery after dried up”:

Click to access ENGNEWS01_1300252224P.pdf

and similar wording in their report $5 on the 15th:

Click to access ENGNEWS01_1300170541P.pdf

It might be helpful to go back and review all those old daily reports:

http://www.jaif.or.jp/english/news_index.php

I’m not posting this to suggest I have some opinion on the vessel integrity issue. I don’t. I’m just making sure this old info is considered by all… this could also be the source of Richard Lahey’s “indication of reactor condition” that was questioned above.

Like

I don’t think we have to go to the situation where the fuel has melted through the reactor vessel for there to be large radiation readings in the water found in the turbine building. The fuel could be partially melted in the vessel, and the radioactivity that has been released there is getting out in the steam and into the torus and from there out of the containment, or directly from the circulatory system. Aren’t they trying to cool the reactors more normally now? If they are taking water out of the core to cool it somewhere sounds like lots of opportunities for a leak somewhere, especially since this is hot salty (i.e. corrosive water). This seems like the most likely scenario to me.

Like

@ Spark

Hey! That’s the same stuff on eye strips used to detect corneal scratches!

Dunno what sort of volume x kg of the stuff is (probably easy to find on web), e.g., if it would be do-able in that regard, but looks like it might.

Apparently it’s a disodium salt, tho. Melting point 320 C. & for the material itself: “Incompatibilities with Other Materials: Strong oxidizing agents.
Hazardous Decomposition Products: Carbon monoxide, carbon dioxide, sodium oxide”

Really would take folks expert in both radiochemistry (maybe moot now with sea water etc., I just don’t know) and plant systems, maybe even multiple people for systems, because they’d need to be intimately familiar with all the various pathways that could be involved, to determine if adding something like that would be safe & useful.

Have to wonder if the thought has even crossed their minds tho….

Like

re post by: David Martin, on 30 March 2011 at 10:15 AM

David, read this thread a bit earlier than your post, starting at: Rational Debate, on 30 March 2011 at 6:37 AM and several related posts following that one.

Like

re post by: Barry Brook, on 30 March 2011 at 11:16 AM said:

Rational Debate — re: technical open thread + philosophical open thread — yes, I think that’s a good idea.

Thanks Barry! I’ll keep an eye out for it.

With WordPress at present, the blog owner must choose whether to have all threads either chronological or threaded. So the options are limited.

Right, I totally understand currently options are limited (and I’d pick chrono too). Maybe I wasn’t making myself clear, however. I’m asking you folks to please consider contacting wordpress to push them to add a new feature for us, e.g., a toggle between chronological & threaded versions. :0) No need to reply to this unless you feel like it, as I know there isn’t a ‘resolution’ or any change that you can make to what we’re seeing – I’m just hoping that you’ll let wordpress know this is something we would all like. Heck, tell them a bazillion of us have begged you for it and keep pestering you about it – blame us! {grin}

Like

Double breaches at Fukushima Daiichi No. 2?

[reposted from Fukushima Open Thread 2]

Former US Navy Reactor Operator Will Davis blogs at Atomic Power Review. Yesterday he offered a thesis for large reactor leaks at Daiichi No. 2 — essentially a “conservation of core coolant volume”. What can we infer when we observe a volume of contaminated water exiting the “controlled area” – which exit volume is almost as large as the volume of water being injected for core cooling? I’ve asked Will for links to the evidence supporting this input/output volume premise.

Meanwhile I’ve re-reviewed the status reports. E.g., the latest March 29 IAEA presentation shows Unit 2 “Core and Fuel Integrity” has jumped to “Severe damage”. On the previous day March 28, unit 2 was reported the same as units 1,2 = “Damaged”.

The RPV pressure reports are: unit 1 = “Slightly increasing” (due I think to restricting the volume of core cooling water); while units 2,3 = “Stable”. Looking for confirmation of Will Davis’ thesis, I’ve examined the reactor status reports for evidence of RPV pressure drop on unit 2. I don’t see it – TEPCO continues since around 20 March to operate unit 2 below one atmosphere – about 0.074 MPa, or 3/4 atmosphere absolute. I read unit 3 as stable around 1.3 atmospheres = 0.135 MPa.

A contrary opinion on large leaks, as I reported earlier regarding unit 3 leak concerns, nuclear chemist Cheryl Rofer observes that…

(…) If there is a leak, it is not a big one.

It’s not a big one, because reactor #3 has been pressurized. If you try to blow up a balloon with a big leak, nothing happens. You can blow up a balloon with a pinhole leak, though. The steel reactor containment vessel is equipped with pressure gauges to measure the pressure. With a big enough leak, the pressure wouldn’t rise, but it has been rising as water is pumped in and turns to steam.

So where is the radioactive water coming from?

Obviously I don’t know the source. But I don’t understand the RPV pressure quite the same way Cheryl does. I think the feedwater flow rate into the RPV is a function of the relative pressure (feed pressure must be higher than RPV pressure).

As to where is the unit 2 water coming from, I found the following plausible. Barry Brook tweeted the link to this article, which was originated by anonymous poster KBMAN on daily Kos. I’ve not posted anything at BNC on the KBMAN diaries as I expected Barry would post something unless he found the source not credible. But we know Barry is just wee bit busy, so I will stick my neck out – check it out, see what you think.

I’ve done a quick survey of KBMAN’s credentials and other writing on nuclear topics. My judgement is the writer is not a crank, he looks to know his subject, and intellectual integrity looks solid. I’ve assembled some KBMAN resources here, and here. Yes I know he is posting in a place where I would not normally expect to find informed commentary on matters nuclear, but don’t let that deter you:-)

Like

fyi, NISA report, EQ/tsunami related problems at Onagawa NPS. Note, the three stations at this site are all in cold shutdown.

http://www.nisa.meti.go.jp/english/files/en20110330-1.html

….The report was received, regarding the accident and trouble etc. in
Onagawa NPS of Tohoku Electric Power Co. Inc. (the trouble of pump of
component cooling water system etc. in Unit 2 and the fall of heavy oil tank for auxiliary boiler of Unit 1 by tsunami), pursuant to the Article 62-3
of the Nuclear Regulation Act and the Article 3 of the Ministerial
Ordinance for the Report Related to Electricity. (11:16 March 29th) ….

Like

Rad discharge into the ocean is distinctly dropping. I wouldn’t be surprised if it bounces up and down for awhile tho as they try to get a handle on things & depending on how much they spray spent fuel pools, handle the trench & basement water, etc…

http://nei.cachefly.net/newsandevents/information-on-the-japanese-earthquake-and-reactors-in-that-region/

…New analyses of seawater about 1,000 feet from the discharge point of reactors 1 through 4 show “a significant decrease” in radiation levels from March 26, IAEA said.

Readings for iodine-131 went from 2,000,000 picocuries (1 picocurie is one-trillionth of a curie) per liter on March 26 to 297,300 picocuries per liter on March 27. Readings for cesium-137 went from 324,324 picocuries per liter on March 26 to 51,351 picocuries per liter on March 27. IAEA said that radiation readings in seawater “will be quite variable in the near future depending on water discharge levels.” …

Like

‘Meanwhile, tests revealed radioactive iodine at more than 3,000 times the normal level in ocean water near the plant — a new high, Japan’s nuclear safety agency said Wednesday.

The Nuclear and Industrial Safety Agency said monitoring data collected Tuesday afternoon detected the I-131 isotope at 3,355 times the normal level.

The sample was taken 330 meters (1,080 feet) away from one of the plant’s water discharge points, the agency said.

Radiation readings from seawater outside the plant have fluctuated. They spiked Sunday, then dropped a day later.

Officials did not pinpoint a particular cause for the higher readings.

But officials and experts have noted that workers at the plant face a difficult balancing act as they struggle to keep reactors cool and prevent radioactive water from leaking into the ocean.

Water has been a key weapon in the battle to stave off a meltdown at the facility. Workers have pumped and sprayed tons of water to keep the plant’s radioactive fuel from overheating, and the plant is running out of room to store the now-contaminated liquid.

“They have a problem where the more they try to cool it down, the greater the radiation hazard as that water leaks out from the plant,” said Jim Walsh, an international security expert at the Massachusetts Institute of Technology.’

http://edition.cnn.com/2011/WORLD/asiapcf/03/30/japan.nuclear.reactors/index.html?hpt=T2

Perhaps they have decided to flush, but are doing it quietly so as to avoid being stopped due to politics?

Like

‘Smoke was spotted at another nuclear plant in northeastern Japan on Wednesday, Tokyo Electric Power Co. said.

The company said smoke was detected in the turbine building of reactor No. 1 at the Fukushima Daini nuclear power plant around 6 p.m. (5 a.m. ET).

Smoke could no longer be seen by around 7 p.m. (6 a.m. ET), a company spokesman told reporters.

The Fukushima Daini nuclear power plant is about 10 kilometers (6 miles) from the Fukushima Daiichi nuclear power plant, where workers have been scrambling to stave off a meltdown since the March 11 earthquake and tsunami knocked out cooling systems there.

Tokyo Electric Power Co. owns both plants.

After the dual disasters, Japanese authorities also detected cooling-system problems at the Fukushima Daini plant, and those living within a 10-kilometer radius (6 miles) of Fukushima Daini were ordered to evacuate as a precaution.

But since then, officials have not expressed any concerns about possible meltdowns there.

Earlier Wednesday, the Japanese Atomic Industrial Forum, a trade group, said cooling functions were recovered and all the plant’s four reactors were in cold shutdown.’

http://edition.cnn.com/2011/WORLD/asiapcf/03/30/japan.daini/index.html?hpt=T2

Like

‘Complicating matters, the tanks storing the contaminated water are beginning to fill up. Pumping at one unit has been suspended since Tuesday night while workers scramble to drain a new tank after the first one reached capacity. And the water just kept coming Wednesday, when a new pool was found.

In another effort to reduce the spread of radioactive particles, TEPCO plans to spray resin on the ground around the plant. The company will test the method Thursday in one section of the plant before using it elsewhere, Nishiyama said.

“The idea is to glue them to the ground,” he said. But it would be too sticky to use inside buildings or on sensitive equipment.

The government also is considering covering some reactors with cloth tenting, TEPCO said. If successful, that could allow workers to spend longer periods of time in other areas of the plant.

Meanwhile, white smoke was reported coming from a plant about 10 miles (15 kilometers) from the troubled one. The smoke quickly dissipated and no radiation was released; officials were looking into its cause. The Fukushima Daini plant also suffered some damage in the tsunami but has been in cold shutdown since days after the quake. ‘

http://www.independent.co.uk/news/world/asia/setbacks-mount-in-japan-at-leaking-nuclear-plant-2257470.html

Like

‘Tsunami likely filled trenches
30 March 2011

Analysis of the trenches at Fukushima Daiichi indicates they were probably flooded by the tsunami. Low radioactivity in one trench may result from capture of radionuclides from the air but high levels in another are unexplained.
Tokyo Electric Power Company (Tepco) announced the flooding of three large trenches yesterday. Each of the four units in the main part of the site has an underground trench for piping and cabling that runs from the basement of the turbine building. These were separately found to be flooded some days ago, leading to speculation about possible pipe breaks in the reactor circuits, but it now appears likely that both flooding effects are direct results of the tsunami that overwhelmed the power plant.
But while an answer appears close on the presence of the water, the levels of radioactivity remain unexplained.
The trench at unit 2 is a serious concern due to radiation levels from surface measurement in excess of 1000 millisieverts per hour. Further sampling has not yet taken place due to this extraordinary level, and it is not clear if the dose rate is representative of the whole 6000 cubic metre body of water, although it does match the level in the basement of the turbine building. Unit 2 suffered suspected damage to its torus suppression chamber on the morning of 15 March.
At unit 1 the dose rate at the water’s surface is low at 0.4 millisieverts per hour. Tepco said it considers that this trench at least was filled by the tsunami, while “radioactive materials that have been released to the air were captured by rainfall, taken to the trench and diluted by the seawater.” The company will treat the water – up to 3100 cubic metres – in the same way as the water in the basement of unit 1’s turbine building. This is being pumped to the condenser unit higher up in the building for temporary storage.
The pools of water in the turbine buildings had led to speculation about pipe breaks in the reactor circuits, but it now seems more likely that the tsunami filled the trenches and simultaneously caused the internal flooding.
Radioactivity of the trench at unit 3 is due to be sampled today, after the removal of tsunami debris that obstructed work yesterday. It was in unit 3’s turbine building pool that workers were exposed to over 170 millisieverts in a matter of hours.
At unit 4, Tepco said, it is not safe to take a sample because of obstacles around the trench. “We need to study the procedure in advance,” said the firm.’

http://www.world-nuclear-news.org/RS_Tsunami_likely_filled_trenches_3003112.html

Like

More detail on the resin spray:
‘Tokyo Electric said it would begin Thursday testing a solution aimed at preventing the scattering of nuclear particles. The solution is comprised of water and a synthetic resin known as Kuricoat C-720G, which envelops the particles and also adheres to other particles, such as dust. It will be sprayed on the grounds and on the sides of the reactors at the Daiichi plant. If the three-week test is successful, the spraying will continue for as long as necessary, the company said in a statement.’

http://edition.cnn.com/2011/WORLD/asiapcf/03/30/japan.nuclear.reactors/index.html?hpt=T2

Like

‘Overall at the Fukushima Daiichi plant, the situation remains very serious.

With respect to the water that is present in the turbine buildings. In Unit 1, water has continued to be pumped into the condenser with 3 pumps (6.5 ton/hour each) and the water level has reduced from 40cm to 20cm. In Unit 2 from 07.45 UTC, pumping of water from the Condensate Storage Tank into the Surge Tank was started so that the that condenser can be drained to the Condensate Storage Tank and contaminated water can be pumped out from the Turbine building into the condenser. The same process of pumping the water from the Condensed Water Storage Tank into the Surge Tank was started on Unit 3 at 08.40 UTCon March 28.

Near the Unit 3 building, 3 workers spilled water over themselves when removing a flange from seawater pipes on the residual heat removal system (RHR). After showering, contamination was not detected.

Fresh water has been continuously injected into the Reactor Pressure Vessel (RPV) through feed-water line at an indicated flow rate of 8.0 m3/h at Unit 1. The pumping of freshwater into the RPV has been switched from fire trucks to temporary electrical pumps with diesel generator. At Units 2 and 3 fresh water is being injected continuously through the fire extinguisher line at an indicated rate of 7 m3/h using a temporary electric pump.

The indicated temperature at the feed water nozzle of the RPV of Unit 1 has decreased from 323 oC to 281 oC and at the bottom of RPV remained stable at 134 oC. There is a corresponding decrease in Drywell pressure. At Unit 2 the indicated temperature at the feed water nozzle of the RPV has increased from 154 oC to 177 oC and at the bottom of RPV has increased from 78 oC to 88 oC. Indicated Drywell pressure remains at atmospheric pressure. For Unit 3 the indicated temperature at the feed water nozzle of the RPV is about 75 oC and at the bottom of RPV is about 116 oC. The validity of the RPV temperature measurement at the feed water nozzle is still under investigation. ‘

http://www.iaea.org/newscenter/news/tsunamiupdate01.html

Like

TEPCO Washington Office Update:

Here are updates on March 30 at Fukushima-Daiichi and Fukushima-Daini NPS

(1) Result of nuclide analysis of water sampled at the trench of unit 1: Water in the trench was determined as seawater.
(2) Smoke from the turbine building at Fukushima Daini NPS unit 1: It turned out not a fire, but fault in power panel.

Contacts:
TEPCO Washington Office :202-457-0790
Kenji Matsuo, Director and General Manager
Yuichi Nagano, Deputy General Manager,
Masayuki Yamamoto, Manager, Nuclear Power Programs

(1) Result of nuclide analysis of water sampled at the trench of unit 1.
As to the water found in the trench of Unit 1, we conducted radiation measurement of sample collected on Mar 29th. Today, we informed the result of nuclide analysis to NISA and Fukushima prefecture.
We will conduct analysis for Units 2 to 4 on the samples collected from trenches at each unit.

Nuclides (Half life)

Density (Bq/cm3)

Nb-95
(approx 35 days)

Approx 4.7 x 10-3

Tc-99m
(approx 6 hours)

Approx 2.0 x 10-1

Ru-106
(approx 370 days)

Approx 4.3 x 10-1

Ag-110m
(approx 250 days)

Approx 3.6 x 10-2

Te-129
(approx 70 minutes)

Approx 2.1 x 101

Te-129m
(approx 34 days)

Approx 4.1 x 100

I-131
(approx 8 days)

Approx 5.4 x 100

I-132
(approx 2 hours)

Approx 1.8 x 100

Te-132
(approx 3 days)

Approx 1.8 x 100

Cs-134
(approx 2 years)

Approx 7.0 x 10-1

Cs-136
(approx 13 days)

Approx 5.1 x 10-2

Cs-137
(approx 30 years)

Approx 7.9 x 10-1

La-140
(approx 2 days)

Approx 8.1 x 10-2

– Interpretation of the result
— We determined the water in the trench was seawater. For the cable trench is 5 meters higher than the level of water in the turbine building of Unit 1, we don’t believe that the water in the turbine building seeped out to the trench.
— The seawater entered the trench because of Tsunami. We believe that the reason of radiation was, radioactive substances released to the air was captured by rainfall, ran into the trench and was diluted with seawater.
— Volume of the trench is approximately 3,100 m3. We estimate remaining capacity before spilling over is 150m3. (Water in the trench is under3000m3 (about 3100-150))
– Actions
— The radioactive concentration measured at the trench is almost same as the current seawater level. However as radiation was detected, we will consider treating it in the similar way as the puddle water in the turbine building.
— Plans for analysis for other units:
For unit 2, as the radiation level is very high, we can not determine the timing of sampling now. We will consider proper timing with examining the safety (dose) of personnel.
For unit 3, we are planning to collect sample on Mar 30th.
For unit 4, as it is unsafe to conduct sampling because there are rubbles around the trench.

(2) Smoke from the turbine building at Fukushima Daini NPS Unit 1 At approximately 5:56 pm, March 30th, after a unit operator inspected the field when a thermal trip alarm in auxiliary potential transformer of control circuit in the power panel sounded, the operator discovered smoke from power panel (*) at the turbine building Unit 1 (Reactor is in cold shutdown status).
At 5:57 pm, March 30th 2011, TEPCO immediately reported this incident to the local fire department.
Subsequently the fire brigade consisting of TEPCO employee inspected the area. On approximately 6:13 pm, we confirmed the smoke stopped after we stopped electrical supply to the power panel.
At 7:15 pm, the local fire department made a judgmental decision that this incident was caused by a fault of the power panel, they found no signs of fire.
(*) power panel: power supply board to supply electricity to the motor of a drawing water pump to the outdoor duct.

Like

Update to Information Sheet Regarding the Tohoku Earthquake
The Federation of Electric Power Companies of Japan (FEPC) Washington DC Office
As of 10:00AM (EST), March 30, 2011
• Radiation Levels
o On March 30, it was announced that radioactive nuclide I-131 was detected from the seawater sampled near the seawater discharge point of Fukushima Daiichi Nuclear Station at 1:55PM on March 29. The level of concentration was approximately 3,355 times higher than the maximum permissible water concentration set by the government.
o At 6:30PM on March 30, radiation level at main gate (approximately 3,281 feet from Unit 2 reactor building) of Fukushima Daiichi Nuclear Power Station: 159 micro Sv/hour.
o At 6:30PM on March 30, radiation level at west gate (approximately 3,609 feet from Unit 2 reactor building) of Fukushima Daiichi Nuclear Power Station: 106.3 micro Sv/hour.
o Measurement results of environmental radioactivity level around Fukushima Nuclear Power Station announced at 7:00PM on March 30 are shown in the attached PDF file. English version is available at: http://www.mext.go.jp/english/radioactivity_level/detail/1304082.htm
o 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
o At 7:30AM on March 29, transferring the water found at the turbine building to the condenser was suspended because the water level of the condenser became almost full. (Correction of the previous day’s report that stated as of 3:00PM on March 29, transferring the water found at the turbine building to the condenser continues.)
o At 1:00PM on March 30, pressure inside the reactor core: 0.34MPa.
o At 1:00PM on March 30, water level inside the reactor core: 1.6 meters below the top of the fuel rods.
o At 1:00PM on March 30, pressure inside the primary containment vessel: 0.23MPaabs.
o At 1:00PM on March 30, the temperature of the reactor vessel measured at the water supply nozzle: 518.2 degrees Fahrenheit
o As of 4:00PM on March 30, the injection of freshwater into the reactor core continues.
• Fukushima Daiichi Unit 2 reactor
o At 4:45PM on March 29, preparation work to recover and transfer the water found at the turbine commenced.
o At 1:00PM on March 30, the temperature of the spent fuel pool: 118.4 degrees Fahrenheit.
o At 1:00PM on March 30, pressure inside the reactor core: -0.023MPa.
o At 1:00PM on March 30, water level inside the reactor core: 1.5 meters below the top of the fuel rods.
o At 1:00PM on March 30, pressure inside the primary containment vessel: 0.1MPaabs.
o As of 4:00PM on March 30, the injection of freshwater into the reactor core continues.
o As of 7:00PM on March 30, approximately 96 tons of water in total has been injected into the spent fuel storage pool.
• Fukushima Daiichi Unit 3 reactor
o At 1:30PM on March 30, pressure inside the reactor core: 0.018MPa.
o At 1:30PM on March 30, water level inside the reactor core: 1.85 meters below the top of the fuel rods.
o At 1:30PM on March 30, pressure inside the primary containment vessel: 0.1064MPaabs.
o As of 4:00PM on March 30, the injection of freshwater into the reactor core continues.
o As of 7:00PM on March 30, approximately 4,697 tons of water in total has been shot to the spent fuel storage pool.
• Fukushima Daiichi Unit 4 reactor
o At 2:04PM on March 30, TEPCO began to shoot water aimed at the spent fuel pool, with a specialized vehicle normally used for pumping concrete.
o As of 7:00PM on March 30, approximately 960 tons of water in total has been shot to the spent fuel storage pool.
• Fukushima Daiichi Unit 5 reactor
o At 2:00PM on March 30, the temperature of the spent fuel pool: 99.0 degrees Fahrenheit.
• Fukushima Daiichi Unit 6 reactor
o At 2:00PM on March 30, the temperature of the spent fuel pool: 79.7 degrees Fahrenheit.
• Fukushima Daiichi Common Spent Fuel Pool
o At 8:30AM on March 29, the temperature of the spent fuel pool: 89.6 degrees Fahrenheit.
o As of 7:00PM on March 30, approximately 130 tons of water in total has been injected to the spent fuel storage pool.

Our official sources are:
• Office of The Prime Minister of Japan
• Nuclear and Industrial Safety Agency (NISA)
• Tokyo Electric Power Company (TEPCO) Press Releases
• Ministry of Education, Culture, Sports, Science and Technology (MEXT)

Like

JAIF Update #37:

No. 37
Today’s NHK news regarding status of Fukushima Daiichi nuclear power station as of 21:00 on March 30
●Kaieda urges safety steps at other nuclear plants
Japan’s industry minister has urged power companies across the country to secure emergency energy sources for their nuclear power stations. Banri Kaieda told reporters on Wednesday that the accident at the Fukushima Daiichi plant was due to a failure to secure emergency electricity and a loss of cooling systems at the reactors. Kaieda urged utility companies to secure mobile generators as a source of emergency power that can safely cool nuclear reactors, and to ensure water-supply routes for fire engines. He demanded that the companies confirm emergency steps and conduct drills within a month, or stop operating their nuclear power plants. Kaieda added that putting an immediate end to operations at nuclear power plants is out of the question, because Japan relies on them for about 30 percent of its electricity. NHK has learned that 90 percent of the 15 nuclear power stations nationwide, excluding the 2 quake-hit plants in Fukushima, have decided to introduce new emergency power generators, including mobile generators. Some utilities have already conducted simulations for cooling procedures based on a scenario in which emergency generators have failed to work at their nuclear reactors.
Wednesday, March 30, 2011 16:57 +0900 (JST)
●TEPCO halts work to remove radioactive water
The operator of the troubled Fukushima Daiichi nuclear power plant has suspended work to move highly radioactive water from the basement of the turbine building into the turbine condenser at the No. 1 reactor. Tokyo Electric Power Company suspended the operation on Tuesday morning after the condenser became full of water. The work began on Thursday after water in the basement of the turbine building was found to contain radiation about 10,000 times higher than would normally be found inside an operating nuclear reactor. The Nuclear and Industrial Safety Agency says the water is now about 20 centimeters deep, half the initial level. TEPCO is studying a plan to move water from a tunnel outside the turbine building into an on-site waste disposal facility with a capacity of more than25,000 tons. The water contains radioactive substances, and its level is only 10 centimeters below the top of the tunnel. TEPCO also planned to move highly radioactive water from the basements of the turbine buildings of the No. 2 and No. 3 reactors into turbine condensers with a capacity of 3,000 tons each. But both condensers turned out to be full. Plant workers are now using pumps that can draw 10 to 25 tons of water per hour to move water from the condensers’ storage tanks into other tanks. They then hope to move water inside the condensers into the storage tanks and fill the condensers with the highly radioactive water from the basements.
Wednesday, March 30, 2011 16:37 +0900 (JST)
●Air may be leaking from reactors No. 2 and 3
Japan’s Nuclear and Industrial Safety Agency says air may be leaking from the No 2 and No 3 reactors at the Fukushima Daiichi power plant. The agency was responding at a news conference on Wednesday to speculation that low pressure inside the 2 reactors was due to possible damage to the reactors’ pressure vessels. It said some of their data show pressure is low, but there is no indication of large cracks or holes in the reactor vessels. The agency said fluctuations in temperature and pressure are highly likely to have weakened valves, pipes and openings under the reactors where the control rods are inserted.
Wednesday, March 30, 2011 15:15 +0900 (JST)
●Radioactive elements in No.1 reactor tunnel
Japanese nuclear safety officials say radioactive iodine and cesium have been found in water at the Fukushima Daiichi power plant coming from a tunnel outside the turbine building of the No.1 reactor. The Nuclear and Industrial Safety Agency says the levels of radioactive substances detected are low, at one-to-ten percent of those occurring in an operating nuclear reactor. The agency says the type of radioactive substances found in the water in the tunnel indicates some relation to the contaminated water in the basement of the No.1 reactor turbine building. It says the water in the tunnel will not be released into the sea.
Wednesday, March 30, 2011 12:57 +0900 (JST)
●High radiation levels in waters off Fukushima
The Nuclear and Industrial Safety Agency says radioactive iodine in excess of 3,300 times the national limit was found in seawater near the troubled Fukushima Daiichi nuclear plant on Tuesday afternoon. This was the highest measured in waters off the plant. The level of radioactive iodine-131 found 330 meters south of a water outlet of the plant was 3,355 times regulated standards at 1:55 PM on Tuesday. The outlet is used to drain water from the plant’s No. 1 to No. 4 reactors. Radioactive iodine-131 measured 50 meters north of the water outlet of the No. 5 and No. 6 reactors was 1,262 times the regulated standards at 2:10 PM on Tuesday.
This was also the highest reading at this location. An agency official told reporters on Wednesday morning that people in a 20-kilometer radius area from the troubled plant have been ordered to evacuate and the radioactive substance will be significantly diluted in the ocean by the time people consume marine products. The official added that efforts need to be made to prevent the contaminated water from flowing into the sea. Airborne radiation levels continue to decline in most prefectures, including Fukushima and nearby Ibaraki. Municipalities measured the radiation levels between 00:00 AM and 9:00 AM on Wednesday.
Wednesday, March 30, 2011 12:23 +0900 (JST)
●Aerial photos reveal Fukushima plant damage
Aerial photographs of the Fukushima Daiichi nuclear plant show the scope of the devastation caused by tsunami and hydrogen explosions. NHK obtained the high resolution photos taken from an unmanned plane on March 20th and 24th. An aerial survey firm in Niigata Prefecture, Air Photo Service, took them at the request of the plant’s operator, Tokyo Electric Power Company. One photo shows a large hole on the roof of the turbine building of the No.3 reactor. It was apparently created when debris hit the roof in a hydrogen explosion. Part of a pipe is missing between the reactor building and an exhaust stack. Heavy oil tanks were swept away from the pier by the tsunami and drifted 150 meters westward, blocking a road for vehicles needed for restoration work. Containers and passenger cars are piled up at the foot of a hill to the west of the No.4 reactor. Another photo shows pump trucks connected by hoses in a line that stretches from the pier to the first four reactors.
Wednesday, March 30, 2011 08:48 +0900 (JST)
●Radiation levels falling in waters off Fukushima
The science ministry says levels of radiation in seawater near the crippled Fukushima Daiichi Nuclear Power Plant are on the decline. The ministry has been collecting seawater samples at 4 locations 30 kilometers off the coast of Fukushima Prefecture since March 23rd. The locations were at intervals of 20 kilometers from north to south. The ministry started the research after waters near the plant’s drain outlets were found to be contaminated with a high density of radioactive substances. The ministry said 1.5 to 3.9 becquerels of radioactive cesium-137 per liter were found in seawater samples taken on Sunday. The amounts represent 1,000 to 2,600 times the levels measured in the same area 2 years ago. But the current levels are only one-fifth to one-tenth of those detected on March 23rd. The density of radioactive iodine-131 is also decreasing. It now stands at 5.4 to 15 becquerels per liter. The ministry said radiation density in the seawater is higher than normal, but it is declining.
Cesium-137 is said to remain in the environment for a longer time than other substances as it takes roughly 30 years to lose half of its radioactive intensity. The Marine Ecology Research Institute says cesium-137 will not be directly absorbed into fish through gills but some species can accumulate the element by eating plankton and smaller fish. It’s believed that through this process, the density of cesium in fish can increase 10 to 100 times the level in the seawater. It usually takes some time for radioactive material to be detected in fish after it flows into the sea. In many cases, such substances are found in flatfish and Japanese seaperch 2 to 3 months after a confirmed leak into the sea. However, unlike mercury, such elements are eliminated from fish in several weeks.
Wednesday, March 30, 2011 06:25 +0900 (JST)

Like

Radiation levels in the sea up to 4385 normal, cesium-137 527 times standard, high levels in village outside exclusion zone:

‘- The levels of radiation in ocean waters off Japan’s embattled Fukushima Daiichi plant continue to skyrocket, the nation’s nuclear safety agency said Thursday, with no clear sense of what’s causing the spike or how to stop it.

The amount of radioactive iodine-131 isotope in the samples, taken Wednesday some 330 meters (361 yards) into the Pacific Ocean, has surged to 4,385 times above the regulatory limit. This tops the previous day’s reading of 3,355 times above the standard — and an exponential spike over the 104-times increase measured just last Friday.

Officials have downplayed the potential perils posed by this isotope, since it loses half of its radiation every eight days.

Yet amounts of the cesium-137 isotope — which, by comparison, has a 30-year “half life” — have also soared, with a Wednesday afternoon sample showing levels 527 times the standard.

“That’s the one I am worried about,” said Michael Friedlander, a U.S.-based nuclear engineer, explaining cesium might linger much longer in the ecosystem. “Plankton absorbs the cesium, the fish eat the plankton, the bigger fish eat smaller fish — so every step you go up the food chain, the concentration of cesium gets higher.”

On Thursday, Hidehiko Nishiyama, a Japanese nuclear safety official, reiterated that seawater radiation doesn’t yet pose a health risk to humans eating seafood.

Fishing is not allowed within 20 kilometers (12 miles) of the plant, and he claimed that waterborne radiation should dilute over time.

Still, authorities don’t know where the highly radioactive water is coming from.

Nishiyama said it may be flowing continuously into the sea. Another explanation is that water, which authorities have pumped and sprayed in by the tons in recent weeks to stave off a meltdown, became contaminated by overheating nuclear fuel in the process and ended up in the ocean without having any room to settle in the nuclear plant.

“They have a problem where the more they try to cool it down, the greater the radiation hazard as that water leaks out from the plant,” said Jim Walsh, an international security expert at the Massachusetts Institute of Technology.

Persistent rain and wind forced the plant’s owner, the Tokyo Electric Power Company, to postpone Thursday a new fix to contain the spread of radiation: a water and synthetic resin mix to envelop radioactive particles. The plan is to spend at least three weeks spraying the solution on the grounds and sides of reactors at the Daiichi facility.

The nuclear plant has been in a state of perpetual crisis since being rocked by the March 11 earthquake and subsequent tsunami, and there’s no clear end in sight.

This has all left the plant’s owner reeling, with the ordeal taking a significant toll on both its reputation and bottom line.

On Wednesday — the same day the company announced that its president, Masataka Shimizu, had been hospitalized due to “fatigue and stress” — Tokyo Electric’s chairman Tsunehisa Katsumata said it had no choice but to decommission four of the plant’s six reactors.

He acknowledged reports Japan’s government is mulling nationalizing the company after the disaster, saying, “We want to make every effort to stay a private company.”

Beyond the recovery and clean-up expenses, Toyko Electric will likely be asked to pay those who suffered because of the nuclear crisis.

A report from Bank of America Merrill Lynch estimates the utility firm will face 1 trillion Japanese yen ($12.13 billion) in compensation claims if the recovery effort lasts two months, rising to 10 trillion yen if it goes on for two years, said Takayuki Inoue, a spokesman with the financial giant.

That might include farmers, their livelihoods shattered after the detection of high radiation in several vegetables prompting the government to ban sales. Contaminated tap water also has prompted officials to tell residents in some locales to only offer bottled water to infants. Businesses have been hit hard, too, by rolling blackouts tied to the strained power grid.

But those most affected have been the thousands, living within 20 kilometers (12 miles) of the stricken plant, who have been ordered to evacuate.

The International Atomic Energy Agency on Thursday urged Japanese authorities to “carefully assess the situation” — and consider expanding the evacuation zone further — after high radiation levels were found in Iitate, a town of 7,000 residents 40 kilometers northwest of the nuclear facility.

The U.N. agency did not say how much radiation it had detected, though the environmental group Greenpeace said Sunday it found levels more than 50 times above normal.

Koboyashi Takashi, Iitate’s manager for general affairs, said radiation levels in soil and water were decreasing. Residents had temporarily evacuated, but later returned to take care of livestock, he said.

Another village official, who declined to be named, was irked Thursday after the earlier radiation readings surpassed the IAEA’s evacuation criteria but not those of the Japanese government. He said local officials have urged tests on soil from 70 locations around the village.

“We (have to) believe what the government tells us,” said the Iitate village official in apparent frustration. “There is no other way.”

Japanese Chief Cabinet Secretary Yukio Edano told reporters Thursday the “IAEA results will be taken into consideration,” but said “there is no plan” to expand the evacuation zone to 30 kilometers or beyond.

“There is no immediate health hazard,” Edano said. “If the exposure continues for a long period of time, (a negative) impact can occur. We will continue to survey the situation.”‘

http://edition.cnn.com/2011/WORLD/asiapcf/03/31/japan.nuclear.reactors/index.html?hpt=T2

Like

Tens of thousands evacuated from around the stricken Fukushima Daiichi power plant may not be allowed home for months, a Japanese minister said Friday, with no end in sight for the nuclear crisis as fresh concerns mount about alarming radiation levels in beef, seawater and groundwater.
While he didn’t set a firm timetable, Chief Cabinet Secretary Yukio Edano said people who’d lived within 20 kilometers (12 miles) of the nuclear facility would not return home permanently in “a matter of days or weeks. It will be longer than that.”
“The evacuation period is going to be longer than we wanted it to be,” Edano said. “We first need to regain control of the nuclear power plant.”
The plight of the evacuees and those within a 20-to-30 kilometer radius of the facility, who have been told to stay indoors and encouraged to leave, is one of many storylines still playing out in relation to the crisis. Many are rooted at the northeast Japan power plant where dozens of workers, soldiers and others are rushing to prevent the disaster from worsening, while further afoot farmers, citizens and officials are dealing with the effects of already released radiation.
That includes news Thursday, from Japan’s health ministry, thatradiation higher than the regulatory limit has been found in beef from Fukushima prefecture, the same province as the embattled nuclear plant.
The levels were slightly above the guidelines set by Japan’s Nuclear Safety Commission — 510 becquerels (a measurement of radioactivity by weight), compared to the official limit of 500 becquerels. For reference, Japan earlier set a
Evacuees not to be allowed to return for months.
Radiation in beef just above safety standard.

100-becquerel threshold at which infants shouldn’t drink tap water, with a 300-becquerel maximum for adults.
The meat will not be sold and will be retested, the ministry said.
The finding is the first such in beef, although authorities have banned the sale and transport of numerous vegetables grown in the area after tests detected radiation.

http://edition.cnn.com/2011/WORLD/asiapcf/03/31/japan.nuclear.reactors/index.html?hpt=T2

Like

@ David Martin
It seems that the chosen quotes from the article omit the assessments by officials as to the possible harmful effects to humans. It always pays to follow the link to the story and read it all to get the full-picture. Journalists appear to prefer to overhype the news by relegating appraisals of the situation to the end of the article. Maybe they think we have a short attention span:-)

Like

Ms Perps,
If you mean that the areas I selected did not include information given later there involving concentration in the foodchain, I did not include that as the audience here would be well aware of that and in earlier posrs I had mentioned the cesium 137 in the sea and the iodine levels.
Any selection necessarily omits something, but I do so in the interests of making the post reasonably concise and not overburdening the thread, the same reason why I now provide the main points just above them.
If on the contrary you are referring to an article from which the CNN post was drawn, I did not spot it, so please provide the link.

Like

Ms Perps
You are of course quite at liberty where you feel I have omitted information which seems to you important to provide that information in another quote with the links preferably rather than in an unlinked opinion as to the importance of the information left out.
Everyone’s selection will of course differ from other peoples.

Like

@ David Martin
As I was referring to the article from which you were quoting I saw no reason to repeat the link. However, if you insist:
http://edition.cnn.com/2011/WORLD/asiapcf/03/31/japan.nuclear.reactors/index.html?hpt=T2
And this is another quote from that article:

“Officials have downplayed the potential perils posed by this isotope, since it loses half of its radiation every eight days. Still, authorities don’t know where the highly radioactive water is coming from, how it reached the sea or how it might be stopped.

On Thursday, Hidehiko Nishiyama, a Japanese nuclear safety official, reiterated that seawater radiation doesn’t yet pose a health risk to humans eating seafood.”

I merely suggested that, folk reading the blog should always check the links provided to get the whole story.

Like

[Comment deleted. Violation of citation rule.]
MODERATOR
A throw away statement with a link is not good enough.
Please read this section of the commenting rules before re-posting.
BARRY BROOK This is not a forum for cut-and-pasting slabs of text, with no other comment other than a link. Tell people why you think they should be interesting in reading this, and what it means for this discussion. Otherwise, you’re not thinking and not contributing. Simple as that.

Like

Leave a Reply (Markdown is enabled)

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s