Japan Earthquake: Nuclear Plants at Fukushima Daiichi

[etudiant]

Attached are the basement water sample analysis of 26 March (forget the I-134 that was proven wrong) - the I-131 dilution of the sea sample is 146 million compared to basement 2 water (beware of different units /cm³ and /litre)

Yes - your last statement is correct!
Also the sub-terrain water is equally badly polluted

Apparently Tepco have found the leak, a 20cm long crack that leaks 500m³/day ...

500 m**3/day is about 500 tons, about double the daily water used for reactor cooling at the 150 liter/min rate indicated by the NISA. Suggests this leak is drawing on more than just reactor 2.

Does anyone have any idea of how a thin slurry of irradiated reactor fuel could be stored?
Maybe freeze it in place and wait a few years for decay?

 

[TCups]

The movement of the cloud to the right is almost as far at this time - although the wind is behind it.

The exhaust stack seems to disappear briefly as the shaddow from the large vertical cloud blocks direct sunlight. This is a low contrast video, shot from many km away. Note there is almost no difference in tone between the shaded sides of the builkdings and the background sky.

OK, my bad. I misunderstood.

The propagation of the smoke to the right (toward the northeast) at first glance looked discontinuous. I wondered if there were additional ground impacts kicking up dust and smoke. But just as the shadow from the vertical blast transiently obscures the visibility of the tower between units 1 and 2, it also transiently obscures the apparent continuous propagation of the smoke along the ground.

The ground smoke and dust is likely kicked up, at least in part, by a horizontally propagating shock wave, which would not be, in effect, bucking the wind. The shock wave then kicks up dust and debris on the ground.

Another explanation might be that the southeasterly winds create air currents that, at higher altitudes, cary dust and smoke in a southeasterly direction, toward the sea. But the prevailing winds are blowing from over the high-banked berm and high ground, back to the west side of the buildings, so at ground level, a swirling eddy current of air flow might well be blowing in a different direction as well.

Finally, I would not dismiss the possibility that additional debris blasted outward struck the ground and kicked up more dust that way as well.

 

[Joe Neubarth]

How come we are all still alive?

Resistance to some background radiation is built into our biochemistry, we evolved this way as the radiation was always with us. It is dose that makes a poison. I often have a feeling that one of the most important reasons why general public is so afraid of the nuclear energy lies in the fact they were told what you wrote above. Radiation is a not a thing to be treated lightly, but there is no doubt there are levels that are safe. Or at least - their health effect is unmeasurable.

Borek, I am going to disagree with you on this. I am convinced that any radiation in excess of normal background exposure is not good for you and can kill you. It only takes one gamma ray to damage a DNA string in a cell in your skin, lungs, marrow or whatever to start a cancer cell growing.

The first gamma ray to hit you can trigger cancer growth or the Tenth-Trillion one can. Mathematically we have the same chance no matter which gamma ray it is. I have four skin cancers that are more than likely related to solar radiation, but could be from gamma or Beta radiation from my reactor plant operating days. There is no way of knowing which strike of radiation caused the DNA damage that created the cancers. I also have three tumors growing in my body (Well, one might be dying as the surgeons blocked off the arteries feeding the tumor.). That one was on my Kidney, the other two are on my adrenal gland and my diaphragm area. According to the doctors all are benign. One of the skin cancers is aggressive and was removed yesterday amidst a lot of blood. Those suckers grow roots in multiple directions.

Knowing what I know now, I would have stayed away from nuclear power in my youth. I am 63 now and was last in an operating plant in 1973. Nearly forty years from my last exposure to radiation that was not necessary in normal life. I advise anybody and everybody if you do not need the radiation exposure to survive, stay away from it.

The moral to the story is to avoid any extra exposure to radiation if you can. The life you save may be your own.

 

[Astronuc]

500 m**3/day is about 500 tons, about double the daily water used for reactor cooling at the 150 liter/min rate indicated by the NISA. Suggests this leak is drawing on more than just reactor 2.

Does anyone have any idea of how a thin slurry of irradiated reactor fuel could be stored?
Maybe freeze it in place and wait a few years for decay?

I doubt that anyone would want to store a slurry or solution of fission products or fuel.

I would recommend that it be chemically processed in much the same way normal fuel is fabricated. Basically, one simply precipitates the solution. The precipitate is dried, then calcined and finally vitrified, possibly with a glass additive. The solid can then be stored permanently in a geological repository.

One possibility would be to recover the fuel, or fissile and fertile material.

 

[Joe Neubarth]

An old saying:
The only statistics you can believe are those you complied yourself

BUT, even then I do not always trust them.

 

[TCups]

Unit 4 was in a maintenance outage. the green crane to the right was probably a maintenance crane for doing work for equipment in the dryer/separator pool. When a BWR enters an outage, the Rx vessel needs to be disassembled to get access to the Rx fuel. firs the drywell head is removed (thats that big orange dome structure you see in the U4 pictures), then the Rx vessel head insulation, then the Rx vessel head is removed. The drywell head, Rx head insulation and Rx vessel head are stored on the refuel floor.
Next the Rx steam dryer and then the Rx steam separator are removed from the Rx pressure vessel. These items are large and have some level of contamination so they are stored in a large swimming pool/pit.

@michael20

The damage to the lower levels of both Bldg 3 and 4 have been puzzling. I think I know how hydrogen got into the lower levels of Bldg 3, but I am darned if I can figure out a mechanism for the apparent blast in the lower levels of Bldg 4 resulting from hydrogen formed in the SFP4.

I did just read one interpretation that "hot" spent fuel rods were in the accessory SFP4 (what is the proper name?) and that the smaller pool adjacent to the larger SFP4 was damaged, breeched, and dumped glowing hot fuel rods, accounting for reports of recurring fires in Bldg 4.

 

[TCups]

Even the strength of the blast at Unit 3 did not blow out every single wall panel of the floor below the top (reactor access) floor. And the top floor (the top two tiers of columns) is where hydrogen was most likely to accumulate. Not only did the explosion at unit 4 take out every panel on the east and west side of the building of the floor below the reactor access floor (ie, at the same level as the SFP), it also appears to have taken out one south side panel a floor below the SFP (ie, two floors below the reactor access floor) and also, it did much less damage to the roof beam superstructure than did the blast at Unit 3, and it left the north wall of the top floor partially collapsed inward, and it left at least two panels on the east and west sides of the top floor intact. Compare, carefully, the east, west, and south elevation views.

http://nimg.sulekha.com/business/original700/aerial-2011-3-30-1-11-12.jpg

http://nimg.sulekha.com/business/original700/aerial-2011-3-30-0-20-7.jpg

http://nimg.sulekha.com/business/original700/japan-earthquake-2011-3-30-0-50-12.jpg

I think I can explain the damages at Bldg 3, but Bldg 4's explosion still has me baffled. Above quote from post #2012

 

[TCups]

SUBLETHAL REPAIR OF CHROMOSOME DAMAGE FROM IONIZING RADIATION FOR DUMMYS


(corrections welcome - it's been a long time since I studied it)

Borek, I am going to disagree with you on this. I am convinced that any radiation in excess of normal background exposure is not good for you and can kill you. It only takes one gamma ray to damage a DNA string in a cell in your skin, lungs, marrow or whatever to start a cancer cell growing.

The moral to the story is to avoid any extra exposure to radiation if you can. The life you save may be your own.

Joe:

http://en.wikipedia.org/wiki/DNA_repair

Very simplistic explanation: Biochemically, DNA is a two-stranded mega-molecule. Ionizing radiation does chromosome damage by the ionization leading to free radicle formation (O-1, or oxygen free radicles as I recall) which leads to a break in one side of the DNA strand. In brief, at relatively low exposure rates, and even moderate exposure rates of ionizing radiation, it is far more likely that these ionization events result in damage to only one side of the DNA chain. Only if there is enough radiation exposure to cause a "double hit" and a double chain break in the DNA strand, is irreversible damage done to a DNA strand and thus, irreparable chromosomal damage.

Biochemically, there are single strand breaks going on all the time from a number of causes, but the body has a very efficient way of repairing these. Reverse DNA transcriptase attaches to one side of the DNA strand and, in effect by reading one side of the chain, repairs the break in the other side, like a zipper. But if this reparative enzyme encounters a break in both strands simultaneously (both sides of the zipper are broken) it can't make the repair.

But double chain breaks are uncommon except in very high, single exposures to ionizing radiation (alpha, beta, x-ray, gamma), with one exception: alpha particles. This is because of the high mass and double charge of the alpha particle (2P+2N)++ vs beta (1e)- vs x-ray and gamma (photons, no charge). But alphas don't penetrate from external exposure. On the other hand, if you ingest an alpha emitter, you are probably screwed (can I say screwed on this forum?)

At exposure rates sufficient to have a high enough number of ionizing gammas to statistically cause a high number of double chain breaks, then, yes, permanent damage is done. At lower exposures, and probably even moderately high exposures, it is probably business as usual for the DNA machinery of living organisms.

Take a big dose of Vitamins E and C (anti-oxidizing agents, fat and water soluble respectively) if you are worried about low level radiation exposure, and relax. Again, look up the Mega Mouse Project for some interesting reading.

It theoretically might only take one alpha "hit" on a critical part of a cancer forming or cancer preventing chromosome (read up on oncogenes, proto-oncogenes, etc. in your spare time) to start a cancer, perhaps, but the probability of a single ionizing event from any other source of radiation causing a cancer is non-existent, IMO.

 

[AntonL]

... I am convinced that any radiation in excess of normal background exposure is not good for you and can kill you. It only takes one gamma ray to damage a DNA string in a cell in your skin, lungs, marrow or whatever to start a cancer cell growing. ...

What is normal background radiation - do we have references on background radiation before 16 July 1945. All I know is that steel from warships sunk before 1945 is being salvaged to line and shield laboratories for sensitive low level radiation measurements. Steel produced today has a higher background radiation due to diluted atomic radiation entrapped into it during the manufacturing process, this we now simply define as normal background.

Radioactivity in the atmosphere has increased over time with the continual testing of atomic bombs of all types. Steel makers need vast amounts of air to make steel so it would follow that steel made nowadays contains certain amounts of radioactivity. Prior to dropping the first A bomb in 1945, steel was radioactive free, and the only source of this 'clean' steel left lies in pre 1945 wrecks that lie on the seabed.

A bit off topic
http://www.youtube.com/watch?v=jfpQNfcRE1o&feature=player_embedded
of the 2053 suns there have been 711 in the atmosphere or underwater: 215 by the U.S., 207 by the Soviet Union, 21 by Britain, 45 by France and, 23 by China. Approximately 3,830 kilograms of plutonium has been left in the ground as a result of all underground nuclear testing and some 4,200 kilograms of plutonium has been discharged into the atmosphere as a result of atmospheric nuclear testing.

 

[hoyrylollaaja]

I think I can explain the damages at Bldg 3, but Bldg 4's explosion still has me baffled. Above quote from post #2012

Could it be, that since it was undergoing scheduled stoppage, some doors and hatches were open that in normal running condition would be closed and sealed?

 

[SoSanl]

Hi all, thanks to all for there effort they put into this topic.

found link not sure if this new vid of interior has been post before or not.

http://www.telegraph.co.uk/news/worldnews/asia/japan/japan-earthquake-and-tsunami-in/8420814/Video-of-smashed-interior-at-Fukushima-nuclear-plant.html

or same vid (first link is better u see more):
New Video Shows Smashed Interior of Fukushima Nuclear Reactor

 

[|Fred]

Hi. yes it has, over four time I think: it's building n°4 on the south wall looking at the fuel pull with a wide lens giving a nonnatural perspective

 

[etudiant]

I doubt that anyone would want to store a slurry or solution of fission products or fuel.

I would recommend that it be chemically processed in much the same way normal fuel is fabricated. Basically, one simply precipitates the solution. The precipitate is dried, then calcined and finally vitrified, possibly with a glass additive. The solid can then be stored permanently in a geological repository.

One possibility would be to recover the fuel, or fissile and fertile material.

Well, the question was for the crack effluent, 500m**3/day and super radioactive.
It seems that precipitating anything out of such a volume would be a large task, but it might be hazardous even to filter it.
Maybe buy up some old supertankers and use them for storage.
Tow them somewhere where tropical storms are rare and then work hard to find a way to deal with them.
The more stuff can be put on hold for a while the better, at least for this situation.

In that context, any thoughts on moving out the spent fuel from the undamaged reactors and the common pool, just in case things here get seriously messy and people have to leave?

 

[TCups]

Could it be, that since it was undergoing scheduled stoppage, some doors and hatches were open that in normal running condition would be closed and sealed?

That has been suggested. Even so, to transmit the blast force downward with sufficient force to blow almost all of the walls one level below the top of the SFP4, and several wall panels two levels below, and yet leave most of the superstructure of the roof girders intact, and even have the north wall of the top floor collapse inward speaks to me of a very different kind of explosion, doors opened or closed. A lot of the damage is isolated around the northeast corner of Bldg 4.

I can maybe get to that kind of damage if hot fuel drops through the bottom of one or the other pools in the top floors and causes and additional lower level blast that spreads outward around the reinforced inner walls of the primary containment. But I just can't wrap my arms around the open door theory.

 

[KateB]

SUBLETHAL REPAIR OF CHROMOSOME DAMAGE FROM IONIZING RADIATION FOR DUMMYS


(corrections welcome - it's been a long time since I studied it)
Joe:

http://en.wikipedia.org/wiki/DNA_repair

Very simplistic explanation: Biochemically, DNA is a two-stranded mega-molecule. Ionizing radiation does chromosome damage by the ionization leading to free radicle formation (O-1, or oxygen free radicles as I recall) which leads to a break in one side of the DNA strand. In brief, at relatively low exposure rates, and even moderate exposure rates of ionizing radiation, it is far more likely that these ionization events result in damage to only one side of the DNA chain. Only if there is enough radiation exposure to cause a "double hit" and a double chain break in the DNA strand, is irreversible damage done to a DNA strand and thus, irreparable chromosomal damage.

Biochemically, there are single strand breaks going on all the time from a number of causes, but the body has a very efficient way of repairing these. Reverse DNA transcriptase attaches to one side of the DNA strand and, in effect by reading one side of the chain, repairs the break in the other side, like a zipper. But if this reparative enzyme encounters a break in both strands simultaneously (both sides of the zipper are broken) it can't make the repair.

But double chain breaks are uncommon except in very high, single exposures to ionizing radiation (alpha, beta, x-ray, gamma), with one exception: alpha particles. This is because of the high mass and double charge of the alpha particle (2P+2N)++ vs beta (1e)- vs x-ray and gamma (photons, no charge). But alphas don't penetrate from external exposure. On the other hand, if you ingest an alpha emitter, you are probably screwed (can I say screwed on this forum?)

At exposure rates sufficient to have a high enough number of ionizing gammas to statistically cause a high number of double chain breaks, then, yes, permanent damage is done. At lower exposures, and probably even moderately high exposures, it is probably business as usual for the DNA machinery of living organisms.

Take a big dose of Vitamins E and C (anti-oxidizing agents, fat and water soluble respectively) if you are worried about low level radiation exposure, and relax. Again, look up the Mega Mouse Project for some interesting reading.

It theoretically might only take one alpha "hit" on a critical part of a cancer forming or cancer preventing chromosome (read up on oncogenes, proto-oncogenes, etc. in your spare time) to start a cancer, perhaps, but the probability of a single ionizing event from any other source of radiation causing a cancer is non-existent, IMO.

Sorry, as this is my forte, I have to interject here. Double strand breaks ARE repairable. It is more complex, requires more energy, and correct conditions (terrain) but it can be done. Generally by non-homologous end joining. Also free radicals are not always oxygen; they say free radicals 'oxidize' if they go through a redox reaction. It is called "oxidation" because oxygen is one of the most reactive and efficient at this (and probably the first element to be studied involving these reactions). ROS contain oxygen, but "free radicals" as a general term, do not have to. Free radicals are pretty much any ion that causes a redox reaction outside of the homeostatic redox reactions for normal body processes. But, our bodies use ions or "radicals" daily for redox signaling, repairing DNA, etc. Basically, it all depends on the terrain, as to whether your body develops cancer as a result of exposure to ionizing radiation (i.e. how much of those antioxidants are available for your body to neutralize the the FR or ROS). Of course, there are instances where the body has been over-assaulted where it cannot make up the difference of repair to damage, and in that case cell death is the result. (Edit: there are also cases where DNA repair is incorrect, the mitotic check points are compromised, and cancer can develop as a result)
Hope that helps!

 

[TCups]

Unit 4 was in a maintenance outage. the green crane to the right was probably a maintenance crane for doing work for equipment in the dryer/separator pool. When a BWR enters an outage, the Rx vessel needs to be disassembled to get access to the Rx fuel. firs the drywell head is removed (thats that big orange dome structure you see in the U4 pictures), then the Rx vessel head insulation, then the Rx vessel head is removed. The drywell head, Rx head insulation and Rx vessel head are stored on the refuel floor.
Next the Rx steam dryer and then the Rx steam separator are removed from the Rx pressure vessel. These items are large and have some level of contamination so they are stored in a large swimming pool/pit.

There was a good picture of that posted earlier -- the same shot showing the open fuel transfer chute and the fuel handling machine.

 

[Joe Neubarth]

SUBLETHAL REPAIR OF CHROMOSOME DAMAGE FROM IONIZING RADIATION FOR DUMMYS


(corrections welcome - it's been a long time since I studied it)



Joe:

http://en.wikipedia.org/wiki/DNA_repair

Very simplistic explanation: Biochemically, DNA is a two-stranded mega-molecule. Ionizing radiation does chromosome damage by the ionization leading to free radicle formation (O-1, or oxygen free radicles as I recall) which leads to a break in one side of the DNA strand. In brief, at relatively low exposure rates, and even moderate exposure rates of ionizing radiation, it is far more likely that these ionization events result in damage to only one side of the DNA chain. Only if there is enough radiation exposure to cause a "double hit" and a double chain break in the DNA strand, is irreversible damage done to a DNA strand and thus, irreparable chromosomal damage.

Biochemically, there are single strand breaks going on all the time from a number of causes, but the body has a very efficient way of repairing these. Reverse DNA transcriptase attaches to one side of the DNA strand and, in effect by reading one side of the chain, repairs the break in the other side, like a zipper. But if this reparative enzyme encounters a break in both strands simultaneously (both sides of the zipper are broken) it can't make the repair.

But double chain breaks are uncommon except in very high, single exposures to ionizing radiation (alpha, beta, x-ray, gamma), with one exception: alpha particles. This is because of the high mass and double charge of the alpha particle (2P+2N)++ vs beta (1e)- vs x-ray and gamma (photons, no charge). But alphas don't penetrate from external exposure. On the other hand, if you ingest an alpha emitter, you are probably screwed (can I say screwed on this forum?)

At exposure rates sufficient to have a high enough number of ionizing gammas to statistically cause a high number of double chain breaks, then, yes, permanent damage is done. At lower exposures, and probably even moderately high exposures, it is probably business as usual for the DNA machinery of living organisms.

Take a big dose of Vitamins E and C (anti-oxidizing agents, fat and water soluble respectively) if you are worried about low level radiation exposure, and relax. Again, look up the Mega Mouse Project for some interesting reading.

It theoretically might only take one alpha "hit" on a critical part of a cancer forming or cancer preventing chromosome (read up on oncogenes, proto-oncogenes, etc. in your spare time) to start a cancer, perhaps, but the probability of a single ionizing event from any other source of radiation causing a cancer is non-existent, IMO.

Your comment is appreciated and educational. The fact remains that ONE piece of radiation is all it takes to start a cancer growing and cancer kills millions annually. Yes, both strand sides of DNA have to be damaged for a permanent change to occur, but that can happen from one ray. Though it is most likely that it would take two rays to damage the DNA stand about the same time, it is still one ray that does the final damage. If it is the second one, so be it. If you never were exposed to it you would not have the cancer. Such is life, and death.

 

[|Fred]

The Tepco press point that just finished talk about the picture of unit 4 .. I did not understand much (understatement) , they seems to pay attention to the pipes bellow though.

The missing data.,so far we did not have much data related to the reactor before the 12th evening now we have a bit more

[PLAIN]http://k.min.us/imHJgS.jpg

 

[KateB]

Your comment is appreciated and educational. The fact remains that ONE piece of radiation is all it takes to start a cancer growing and cancer kills millions annually. Yes, both strand sides of DNA have to be damaged for a permanent change to occur, but that can happen from one ray. Though it is most likely that it would take two rays to damage the DNA stand about the same time, it is still one ray that does the final damage. If it is the second one, so be it. If you never were exposed to it you would not have the cancer. Such is life, and death.

You can develop cancer if only one side is compromised. In transcription, only one side of the DNA is used, called the template strand. If this strand has one or more base pair substitutions/deletions/etc., it could code for the wrong amino, making an incorrect protein (proteins are the major regulatory mechanism of cells). Also if a start or stop codon is compromised, you could have an incorrect protein made (or no protein made at all) as well. Lentiviruses work in this manner to cause cancer as well. If they incorporate into the DNA in the right area (which for unknown reasons, viruses will incorporate themselves into active genes) , they can cause cancer to develop as a result.

 

[michael200]

TCup: this is in reply to your post #2521. I posted a reply to an article that appears on the Atomic insights blog
http://atomicinsights.com/2011/04/fukushima-nuclear-accident-exceptional-summary-by-murray-e-miles.html

I'll repost here since I don't know if the moderator of the other website has accepted it for general public:

In my humble opinion it would be nice if people could get their facts right:

“You need to hear one more complication in the design. The fuel pool is really two pools separated by a gate. Fuel removed from the reactor goes first into the small, upper pool which is only 20 or 25 feet deep. Later they move the fuel to the big, deep pool. There was apparently only a little fuel in this upper pool at the time of the quake.

This UPPER pool broke. The three-eighths inch steel liner is cracked and will not hold water. The concrete wall in front of this upper pool fell off. Fuel was severely damaged probably by explosion. Temperature profiles measured by helicopters show clumps of hot stuff that must be fuel scattered around the floor area. This scenario is consistent with the numerous reports of fire in unit 4.”

The BWR MKI and MKII reactor building designs have only a single fuel pool for each unit. There is no “small upper pool and lower pool separated by a gate”. I believe that the author is referring to the BWR Mk III design where this is a true statement but has NOTHING to do with the issue a Fukushima concerning fuel pools.
Since there is such conjecture on the events at Fukushima, I’ll throw in my 2-cents: there are currently operators at 30+ BWR plants in the US with their mouths gaping open concerning the OPERATOR ERROR/MANAGEMENT ERROR that allowed any damage at Unit 4. When the earthquake/tsunami hit, the ONLY action that the operators had to take for Unit 4 was to maintain inventory in the spent fuel pool (there was NO fuel in the Reactor pressure vessel). If they needed to do this by injection of seawater – they should have done it. Regardless of the damage caused by the tsunami, there was MORE THAN ADEQUATE time to use a diesel driven fire pump or rig up temporary pumps to add water. My only conclusion on this event is that the Japanese had INADEQUATE planning, procedures and training to deal with a relatively simple issue for Unit 4.

As far as the more serious/difficult scenario for Units 1,2, and 3: My view is as follows: 1. NO PLANT in the world can currently cope with a station blackout greater than 3 days (currently they are at 21 days in japan) without core damage. However, US plants have emergency procedures and mitigating actions to connect temporary pumps/power supplies to ensure restoration of core and containment cooling. I challenge someone to show me the japanese coping studies for SBO 2. Concerning the issue with the uncontrolled release of radioactive materials, which is caused by the loss of secondary containment (blown up Rx buildings) and possible primary containment on Unit 2 (overpressurized to greater than 2x design pressure by OPERATOR ERROR): the japanese either didn’t have installed or didn’t use a hardened containment wetwell vent that is installed at all US MKI BWRs per NRC GL 89-16. The vent was specifically mandated to avoid containment failure if events propogated to the situation where a core melt with high H2 generation could occur. The japanese operators also would have VIOLATED US plant emergency operating procedures /severe accident guidelines to vent the wetwell when the containment design pressure is reached and no containment/core cooling is available (containment design pressure is about 56psig and they reach greater than 120psi containment pressure before they vented).

Time will tell, but the entire situation in japan looks starkly similar to the same issues that occurred at TMI 30 years ago – lack of preparedness and lack of procedural guidance/training. Frankly, I’m a bit concerned at the Ex-navy nuke (Toy PWR)/commercial PWR community bashing of the BWR design and accident mitigation scenarios. Unless they have KNOWLEDGE, they shouldn’t be speculating. Perhaps this is payback for what the BWR designers said about TMI: if the initiating event that caused the TMI meltdown (stuck open primary system relief valve) had occurred at a BWR, then nothing would have happened.

BTW: I’m ex US Navy submarine officer/engineer with 27 years experience in BWR design, testing and operation

 

[ivars]

https://www.physicsforums.com/newreply.php?do=newreply&noquote=1&p=3225300"

Tokyo Electric Power Co. took steps to encase the fracture in concrete as an emergency measure but the utility said later that the amount of leakage was unchanged even after the measure was taken.

The utility, known as TEPCO, said the pit is connected to the No. 2 reactor's turbine building and a tunnel-like underground trench, in which highly radioactive water has been spotted so far.

It will try to block leakage of such water by injecting polymeric material into the trench on Sunday and use additional concrete to fill the crack in the 2-meter deep pit measuring 1.2 meters by 1.9 meters.

The tainted water about 10 to 20 centimeters high was found at the bottom of the pit at around 9:30 a.m. Saturday and was leaking to the sea from the crack.

The first detection of tainted water flowing out into the Pacific Ocean could force the government and the operator to limit further expansion of radioactive contamination, likely hampering efforts to restore the crippled cooling functions at the complex.

 

[hbjon]

You can develop cancer if only one side is compromised. In transcription, only one side of the DNA is used, called the template strand. If this strand has one or more base pair substitutions/deletions/etc., it could code for the wrong amino, making an incorrect protein (proteins are the major regulatory mechanism of cells). Also if a start or stop codon is compromised, you could have an incorrect protein made (or no protein made at all) as well. Lentiviruses work in this manner to cause cancer as well. If they incorporate into the DNA in the right area (which for unknown reasons, viruses will incorporate themselves into active genes) , they can cause cancer to develop as a result.

Isn't it true Kate that human physiology utilzes methods and chemical reactions that will be mysteries for years to come? The human cell at an individual level seems to have an innate understanding of how to go about it's activity with the best chance of optimum survival. Cancer may be the best outcome with a high dose of radiation as the suppressor.

 

[hbjon]

Isn't it true Kate that human physiology utilzes methods and chemical reactions that will be mysteries for years to come? The human cell at an individual level seems to have an innate understanding of how to go about it's activity with the best chance of optimum survival. Cancer may be the best outcome with a high dose of radiation as the suppressor.

Just to briefly follow a tangent from my last post on human cells and cancer. In the complex algorithms of cellular repair, a decision seems to be made to take the choice of the lessor of two evils. Cancer or death. Perhaps the organism thinks it may be able to work with the cancer and convert it back to "self" at some point in the future. Just an idea.

 

[TCups]

Just to briefly follow a tangent from my last post on human cells and cancer. In the complex algorithms of cellular repair, a decision seems to be made to take the choice of the lessor of two evils. Cancer or death. Perhaps the organism thinks it may be able to work with the cancer and convert it back to "self" at some point in the future. Just an idea.

Not to get lost in a lot of complexity of radiation biology here, the main points are:

1) there are effective biologic mechanisms for cellular repair of repetitive, sub-lethal doses of radiation.

2) the effects of intermediate and long term accumulated lifetime doses are not the same as the same cumulative dose received in a single exposure.

3) the interpolative methods that are used to arrive at the radiation safety recommendation that "there is no safe, low dose of radiation" is just that, an interpolation of incomplete data.

4) the risk of radiation induced cancer, at whatever limits of exposure that occurs, is a relative risk, and the relative risk of radiation exposure must always be weighed against other potential risks and benefits (eg. the risk of radiation induced cancer may go up from a single transcontinental airline flight, yes, but the risk of injury or death from driving from New York to Los Angeles is much higher, and there may also be a significant benefit in getting to LA a few days earlier.

And yet, as a worker in the field of radiation, this I can tell you as absolute fact: There is an irrational fear of radiation by those who are told "even one piece" (piece?) of radiation might cause a cancer.

 

[razzz]

Didn't I just get done telling them not cover over the damage without knowing where it is first?

You have a crack in a box culvert so you know it is structurally compromised, so what do they do, add dead weight to it. Not only that, they can't see the crack anymore to observe and monitor it. If this is how conditions are going to be responded to, then things can only get worse.

Polluting the Pacific is a given for the immediate future, pretending to stop the pollution with superficial actions is fallacy.

Didn't I read a press release issued by the company that readings from samples would no longer be reported unless the readings were higher than recent past samplings? As they raise the background thresholds they also reserved to determine what they are. Sly.

 

[trinon]

CTBT measurements of iodine 131 concentration in air released by bfs.de [PLAIN]http://www.bfs.de/de/ion/aktivitaetskonzentrationen_jod.jpg

The numbers are in logarithmic scale of Bq/m^3. In the legend are the http://www.bfs.de/de/ion/animation.gif" of the CBTB measurement grid given. The slashed line corresponds to the historically highest measured value in Munich after the Chernobyl accident.

Also the norwegian NILU-ATMOS institute is forecasting release dispersals. You can choose the region and a animated forecast is computed for the next 3 days:
http://transport.nilu.no/products/fukushima"
It is based but not identical to ZAMG data

And I think a whole http://eurdepweb.jrc.ec.europa.eu/PublicEurdepMap/Default.aspx" covering real-time data from all european states was also not yet posted here.

 

[jensjakob]

Is there a dead worker in a white protection suit along the bottom middle of the shot in the beginning? That was very unsettling when I saw that.

Propably not. If it were - I guess they wouldn't have released that clip.

But it could look like it...

 

[timeasterday]

Propably not. If it were - I guess they wouldn't have released that clip.

But it could look like it...

Hopefully it's just some other stuff creating the illusion. But I noticed videos released later always cut out that part.

 

[ZZR Puig]

Your comment is appreciated and educational. The fact remains that ONE piece of radiation is all it takes to start a cancer growing and cancer kills millions annually. Yes, both strand sides of DNA have to be damaged for a permanent change to occur, but that can happen from one ray. Though it is most likely that it would take two rays to damage the DNA stand about the same time, it is still one ray that does the final damage. If it is the second one, so be it. If you never were exposed to it you would not have the cancer. Such is life, and death.

Reality is not that clear at all.

Large evidence exists about positive health effects of different kinds as a result of low radiation doses, independently of the possibility of radiation induced cancer without threshold dose. Therefore even if what you say was true, the slight increase in cancer risk could be overcome by strengthened immune system response, for instance, resulting in an overall average increase in life expectancy. The location of the optimum between positive effects and cancer risks is uncertain, but significant evidence points to a non-zero dose value.

This is an interesting piece of evidence that might induce some reflection:
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2477708/"

 

[Joe Neubarth]

You can develop cancer if only one side is compromised. In transcription, only one side of the DNA is used, called the template strand. If this strand has one or more base pair substitutions/deletions/etc., it could code for the wrong amino, making an incorrect protein (proteins are the major regulatory mechanism of cells). Also if a start or stop codon is compromised, you could have an incorrect protein made (or no protein made at all) as well. Lentiviruses work in this manner to cause cancer as well. If they incorporate into the DNA in the right area (which for unknown reasons, viruses will incorporate themselves into active genes) , they can cause cancer to develop as a result.

Thanks, KateB. Gosh, I am learning so much today. I knew that viruses could cause cancer. What is that one, the Papilloma virus or something spelled like that that causes cervical cancer? I did not know until now that one of the ways that a virus can cause cancer was by splicing itself into the DNA of humans. Amazing!

Thanks to people like you, this board has become the most informative board I have ever visited.

 

[M. Bachmeier]

Borek, I am going to disagree with you on this. I am convinced that any radiation in excess of normal background exposure is not good for you and can kill you. It only takes one gamma ray to damage a DNA string in a cell in your skin, lungs, marrow or whatever to start a cancer cell growing.

The first gamma ray to hit you can trigger cancer growth or the Tenth-Trillion one can. Mathematically we have the same chance no matter which gamma ray it is. I have four skin cancers that are more than likely related to solar radiation, but could be from gamma or Beta radiation from my reactor plant operating days. There is no way of knowing which strike of radiation caused the DNA damage that created the cancers. I also have three tumors growing in my body (Well, one might be dying as the surgeons blocked off the arteries feeding the tumor.). That one was on my Kidney, the other two are on my adrenal gland and my diaphragm area. According to the doctors all are benign. One of the skin cancers is aggressive and was removed yesterday amidst a lot of blood. Those suckers grow roots in multiple directions.

Knowing what I know now, I would have stayed away from nuclear power in my youth. I am 63 now and was last in an operating plant in 1973. Nearly forty years from my last exposure to radiation that was not necessary in normal life. I advise anybody and everybody if you do not need the radiation exposure to survive, stay away from it.

The moral to the story is to avoid any extra exposure to radiation if you can. The life you save may be your own.

Joe, I'm not going to disagree with you about potential, but I'd like to add perspective. Radiation above background 'may' be beneficial. Transient radiation from a source not embedded within the biological system, while not dismissible, would require you to win the, (short story) lottery to have consequences, (also not unreasonable to dismiss based on our exposure... to other environmental toxins. I'll bet my two best friends that particulate (radioactive) substances that can both spread and incorporate into living systems are the priority now. If were going to have a valid discussion on this emergency situation it should focus, not on simple radiation readings, but absorption of the more dangerous isotopes.

Joe I'm about to undergo injection 'radiological', as I believe (may be wrong) you have of tc-99 for health assessment. I'm not afraid of the consequences even though it's being physically added biologically.

One word conclusion..., "PERSPECTIVE"

 

[jensjakob]

This picture worries me:
http://english.kyodonews.jp/photos/2011/04/82781.html

If the military takes these precautions - why do we still see workers on the ground in lot less protection?

 

[M. Bachmeier]

BUT, even then I do not always trust them.

I'll give your bonus points on that. Statistics artifacts are misleading, little outside experimental investigation and or social impact. Odds of winning the lottery don't match the winning.

 

[Borek]

To all: please don't continue discussion on the radiation/health issues here. It can be worth its own thread in Medical Sciences, feel free to start one there, but let's concentrate on technical aspects of the Fukushima here.

 

[Bob S]

Astronuc will the radiation meters the workers have detect if they walk near neutron beams? What is your opinion of the neutron beams that was reported earlier at the plant ?

Neutrons and neutron "beams" are very hard to detect with portable instruments. The most common portable instruments
are gas proportional counters using thermal neutron capture in BF₃ (boron tri-fluoride) or He³ gas.
Proportional counters saturate (paralyze) at high counting rates, so are not good in high radiation areas.

http://www.orau.org/ptp/collection/proportional counters/bf3info.htm

http://www.gepower.com/prod_serv/products/oc/en/oilfield_technology/drilling_measurements/he3_neutron.htm

I have used GM tubes wrapped with thin silver foil (Ag¹⁰⁷ activation with 2.3 min lifetime) to detect pulsed neutron beams.
Tissue-equivalent (Shonka) ionization chambers with suitable neutron moderator and gas (ethene) give a good Sievert (rem) response
to mixed (beta gamma neutron) response, even in high radiation fields (when properly designed). See

http://www.orau.org/ptp/collection/ionchamber/shonkatissueequivalent.htm

High energy neutrons produce proton recoils in a hydrogenous gas (like ethene or ethane) in an ion chamber.

Focusing neutrons is like herding cats. Neutrons are produced isotropically. Neutrons diffuse through shielding, and may leak through cracks,
but since they are uncharged, they can be moderated but cannot be focused.

Bob S

 

[M. Bachmeier]

Propably not. If it were - I guess they wouldn't have released that clip.

But it could look like it...

His head gear would not be white. Artifact. digital ?

 

[hbjon]

To all: please don't continue discussion on the radiation/health issues here. It can be worth its own thread in Medical Sciences, feel free to start one there, but let's concentrate on technical aspects of the Fukushima here.

Well then, let me throw this one at you. Is there any fission occurring anywhere in and around the plants in Fukushima? Is there danger of a chain reaction to start going on? There was talk of neutron beams and daughter products in the vicinity of the plant. I think a lot of people want to know if the explosions could have somehow cause the fuel to form a critical mass? What's the danger of having so much fuel in such close quarters? We know that fission needs to have an efficiency of over 1, what is the current efficiency in and around the 4 separate reactors?

 

[sigyn]

From

http://www.nisa.meti.go.jp/english/files/en20110402-2-3.pdf

I see several tens of sieverts/hr in the drywells of 1-3. I think this is about the same as you would get from 5 meter away from BWR fuel rods after 20,000-30,000 MWday/MT burnup from fig 3 in

http://www.osti.gov/bridge/servlets/purl/10137382-BSfGip/native/10137382.pdf

Any guesses on how much of the core is in the drywells ? Either as corium or dissolved in water leaks from the pressure vessel ?

 

[timeasterday]

A couple of construction videos of Fukushima just popped up:

 

[robinson]

1:48 of the second YouTube video of the plant, a good look at the fuel pool/reactor connection. There is a certain sort of horror watching those videos, knowing what we do now.

 

[TCups]

REGARDING THE SPENT FUEL POOLS AT UNIT 4

@michael200
Re: Your post #2535
about this blog:
http://atomicinsights.com/2011/04/fukushima-nuclear-accident-exceptional-summary-by-murray-e-miles.html

I think I follow your post, but please let me make sure.

1) The article you reference has, in your opinion, a factual error in that it suggests that the Mark 1 BWR has only one, not two SFP's. You confirm that there are indeed two SFP's and, further,

2) You suggest it was a critical operator error not to have considered restoring cooling water by any means possible to the SFP's in Bldg 4 as great a priority as restoring cooling water to the cores of Units 1, 2, and 3. Correct?

And to make sure I understand the points, this Mark 1 BWR floor plan:

http://i306.photobucket.com/albums/nn270/tcups/TopFloor-Floorplan.jpg

. . . drafted from this Mark 1 BWR schematic:

http://i306.photobucket.com/albums/nn270/tcups/Picture63.png

is correct, showing the two SFP's (one large, one small, both in blue) as they are located in Units 3 and 4 at Fukushima. Correct?

And the article you reference seems to indicate that the smaller of the two SFP is damaged and spilled hot fuel rods. Has this been confirmed?

Thanks.

 

[shogun338]

Concrete fails to plug leak at Fukushima nuclear plant http://www.latimes.com/news/nationworld/world/la-fg-japan-quake-20110403,0,2146668.story

 

[M. Bachmeier]

With respect, I'd like to make a few observations.

Time line post earthquake, re: 12 hrs. after, where is there concise data about initial measures?

What choices were made, or possible concerning emergency shutdown (borax re:variants, fill)?

Why are such an intelligent group of people concentrating the intellect on partial data instead of a proper forensic analysis of pre/post conditions at the time of this most unfortunate event.

To me the first few seconds of data has more value than supposition upon supposition of 'non-data'. The following 12 hrs. is the basis of a doctoral dissertation.

Challenge: Show me the TEPCO hard data. And, if you tell me it wasn't ported to an external server (run-time, which would be unthinkable) I'd say we've been chasing shadows... but shadows are evident.

A more knowledgeable analysis is in order.

I'm not looking for culpability, but can not escape a educated layman's perspective analysis of a percipient lack of hard data concerning initial conditions.

 

[turbo]

http://i306.photobucket.com/albums/nn270/tcups/Picture63.png

is correct, showing the two SFP's (one large, one small, both in blue) as they are located in Units 3 and 4 at Fukushima. Correct?

And the article you reference seems to indicate that the smaller of the two SFP is damaged and spilled hot fuel rods. Has this been confirmed?

Thanks.

The pool with the thicker walls and floor are for spent fuel. The pool on the opposite side is for contaminated equipment, like perhaps the top of the reactor vessel when removed for re-fueling.

 

[ZZR Puig]

To all: please don't continue discussion on the radiation/health issues here. It can be worth its own thread in Medical Sciences, feel free to start one there, but let's concentrate on technical aspects of the Fukushima here.

I understand and it is convenient to separate discussions about different topics, however is important to offer a short general reference about how worrying are really the technical issues being discussed about this accident. Especially if some Japanese people follow this forum too. Radiation may be dangerous, but fear-fed stress and ill-founded decisions certainly are.

Well then, let me throw this one at you. Is there any fission occurring anywhere in and around the plants in Fukushima? Is there danger of a chain reaction to start going on? There was talk of neutron beams and daughter products in the vicinity of the plant. I think a lot of people want to know if the explosions could have somehow cause the fuel to form a critical mass? What's the danger of having so much fuel in such close quarters? We know that fission needs to have an efficiency of over 1, what is the current efficiency in and around the 4 separate reactors?

There shouldn't be any fission reactions at the plant, other than spontaneous fissions (very low rates), and there seems to be no sign in the available data pointing in that direction. It is also worth to take in account that the fuel assemblies geometry is not only designed to allow a good cooling of the hot fuel, but to achieve a geometry that is nearly optimal from the point of view of fuel-moderator ratio and therefore maximum effective multiplication coefficient. With low-enriched fuel, a more compact geometry, that could conceivably be obtained with molten fuel at the bottom of the reactor is not necessary likely to reach criticality, as it would lack proper neutron moderation. Additionally, it would also be polluted with many other materials present in the reactor, possibly even boron from the control rods. And that would be in the event that the core has undergone extensive meltdown, which is not at all clear right now. Extensive damage is almost granted, but not necessarily significant meltdown.

 

[TCups]

The pool with the thicker walls and floor are for spent fuel. The pool on the opposite side is for contaminated equipment, like perhaps the top of the reactor vessel when removed for re-fueling.

@turbo-1:
Please read again, look at the diagram more carefully --there are 3 pools in the diagram and on my floor plan -- and then let me know the answer. I know about the equipment pool and its location. I am trying to pin down the location of the third pool. Thanks.

 

[M. Bachmeier]

I understand and it is convenient to separate discussions about different topics, however is important to offer a short general reference about how worrying are really the technical issues being discussed about this accident. Especially if some Japanese people follow this forum too. Radiation may be dangerous, but fear-fed stress and ill-founded decisions certainly are.


There shouldn't be any fission reactions at the plant, other than spontaneous fissions (very low rates), and there seems to be no sign in the available data pointing in that direction. It is also worth to take in account that the fuel assemblies geometry is not only designed to allow a good cooling of the hot fuel, but to achieve a geometry that is nearly optimal from the point of view of fuel-moderator ratio and therefore maximum effective multiplication coefficient. With low-enriched fuel, a more compact geometry, that could conceivably be obtained with molten fuel at the bottom of the reactor is not necessary likely to reach criticality, as it would lack proper neutron moderation. Additionally, it would also be polluted with many other materials present in the reactor, possibly even boron from the fuel rods. And that would be in the event that the core has undergone extensive meltdown, which is not all all clear right now. Extensive damage is almost granted, but necessarily significant meltdown.

You speak from, both a lack of data and desire for amortization, I don't advocate rash choices, but consider the human cost in decisions made. Precaution is both expensive and warranted in this case. Unknowns equal unacceptable risks for me and mine.

 

[NUCENG]

That has been suggested. Even so, to transmit the blast force downward with sufficient force to blow almost all of the walls one level below the top of the SFP4, and several wall panels two levels below, and yet leave most of the superstructure of the roof girders intact, and even have the north wall of the top floor collapse inward speaks to me of a very different kind of explosion, doors opened or closed. A lot of the damage is isolated around the northeast corner of Bldg 4.

I can maybe get to that kind of damage if hot fuel drops through the bottom of one or the other pools in the top floors and causes and additional lower level blast that spreads outward around the reinforced inner walls of the primary containment. But I just can't wrap my arms around the open door theory.

The reactor building in a BWR has a large open shaft from the refuel floor down to the ground floor. This shaft allows large loads including fuel shipping and storage casks to be lifted to the refuel floor. During outages this is widw open. During operation there may be tarps or safety nets on the openings at each floor, but it is not air-tight.

The secondary containment (reactor building) is designed to be kept at a negative pressure by normal ventilation during normal operations and by the Standby Gas Treatment System during accidents. The building is not compartmentalized like a submarine so take that for what i may mean during san explosion.

 

[turbo]

@turbo-1:
Please read again, look at the diagram more carefully --there are 3 pools in the diagram and on my floor plan -- and then let me know the answer. I know about the equipment pool and its location. I am trying to pin down the location of the third pool. Thanks.

The "third" pool appears to be a reservoir in which the dry fuel cask can be placed until it is opened and the fuel assembly is removed from the cask for transfer to the reactor. The water is required for shielding when the assembly is out of the cask.

 

[shogun338]

Could this be melted spent fuel 2 flowing out of 1 in this pic of Reactor #4 ?