Japan Earthquake: Nuclear Plants at Fukushima Daiichi

[TCups]

Offsite power wasn't lost until the tsunami about an hour after the earthquake. The plant upset (SCRAM) would have halted any fuel moves in progress. It only takes a few minutes to put a fuel bundle back into the spent fuel pool.

The fuel handling machine has a mast with a gripping "grapple" at the lower end. The mast is telescoping for vertical movement. The FHM is mounted on a trasverse for east west and noth south movement between the spent fuel pool and the reactor cavity. It can be positioned directly over any pool or reactor fuel site.

Basically operator lower the mast, grapllet the rod, raise it up to be clear of the other fuel assemblis, moves it to its destination and the lowers it into place. Release the grapple and move to the next step.

Oh yeah, do it very carefully.

REGARDING THE SEQUENCE OF POWER LOSS

This is not consistent with what I have read and heard the last few weeks, which is:
1) Offsite power was lost at the time of the earthquake.
2) Emergency diesel generators worked properly for almost an hour, then these were disabled by the tsunami.
3) Battery back up power failed in a few hours time, and in less time that it was possible, under disaster conditions, before it was possible to truck in new generators and bring power back on line with them, although desperate attempts were made to do so.

Which scenario is correct? Would emergency diesel power have powered all the functions of the facility, including the fuel transfer machinery? Might the 9.0 quake have in some way disrupted the effort to return the fuel to the proper slot? Might the operators return the fuel rod to its proper slot then get the heck off the fuel handling machine as quick as possible, rush back to the control room, or to wherever their "disaster" station was, and in so doing, have left the mast grappled to the spent fuel rod assembly? This is not known.

REGARDING THE HANDLING OF FUEL, SPENT FUEL POOLS, AND TRANSFER CHUTES

There were two special flat bed trucks parked to the west of unit 3, one empty. I had heard but not confirmed that the implication was that older fuel rods from the SFP were to be loaded into casks for transfer to dry cask storage (or perhaps storage at the 7th SFP facility in wet storage?). I am not familiar with the technical aspect of those sorts of transfer.

As for the "cattle" transfer chute, I believe I understand its size, location and function. In fact, there appear to be two of these -- one at the interface of the reactors upper primary containment, above the level of the drywell cap, and a second between the main SFP and a smaller pool, which, I believe, is used for the cask transfer functions above (not certain of that). There were two potential problems related to the "cattle" chute, neither having anything to do with fuel being in the process of moving through the chute.

1) the seals on the gate(s) between the drywell containment, chute, and SFP are pneumatic and the pressure in the seals is maintained by electric pumps. If the seals are not properly pressurized, it is possible for water to leak from the SFP into the primary (drywell) containment above the level of the drywell cap, but below the "plug" that covers the reactor access, and
2) there are reports that the seals on the drywell cap itself may fail under as little as 2 ATM pressure from the primary drywell containment surrounding the reactor pressure vessel.

The other chute connects a second, smaller pool to the SFP. I have no information about a gate and seal on that chute, but doubt there would be as both these pools are open to air above and share a common water level. The connecting chute is only a few meters deep, however.

I am not an engineer and have no first-hand knowledge, but these issues and potential problems have been discussed here in the past weeks in some detail.

One implication, however, is that there is the potential, under a complete loss of power to have failure of the chute seals, and, possibly, abnormally high pressures within the drywell containment, thus creating a potential pathway for leakage of hydrogen or the explosive release of hot gasses from the primary drywell containment, through the drywell cap seals and through the chute gate seals, at least in theory.

Any solid information or additional relevant comments are appreciated. We are all just trying to understand what happened and why.

PS:
Rod Stewart had it right: "Every picture tells a story"
Let's hope it doesn't turn into a John Lee Hooker blues tune: "Boom, Boom, Boom, Boom"
good night.

 

[shogun338]

Japanese Radiation levels - measured on March 28th - actual footage from Greenpeace.

 

[Bodge]

Given the isotopes already found and their ratios, should we expect to be finding Sr-90 in the contaminated water/soil/air?

 

[shogun338]

Japan soldiers in shadow of Fukushima plant. Fresh water delivered to plant to cool reactors .

 

[NUCENG]

I would like to thank everyone for all the information they have posted here, it has been so exciting to learn so much about Nuclear power generation.

1) Astronuc - You are so freakin smart!

2) TCups - Nice forensic work, it was almost like reading a book. I must say though I was getting stressed out seeing all the work you have put into your posts, I could never do all that :)

3) From the information we have currently, is it safe to assume that everything could have been prevented if the plant never ran out of power?

4) If this happened in the states I would hope that we would be able to mobilize tractor-trailer sized generators & have them patched in within 8 hours?

5) Why would it take several days to run electrical connections from the grid back to the plant? Could you not just block off roads, fields etc. and just unspool a giant cable within a few hours?

6) Why do Nuclear plants have emergency hookups? Why not have 'ports' outside the reactor buildings for fire hoses to connect to that would shower the SFP with water? I understand that they need to have a closed system to prevent accidents, but if an accident does occur then they have no recourse it seems.

7) Again I saw some posts about not having the right generator types, 50 vs 60hz or not being able to splice into the system. Why would they not have an emergency hookup area for extra generators, batteries or external power lines? They could have all the transformers, cables, converters etc. to make connecting so much faster.

8) Could someone design a system where when power is lost that the reactor vessel is continually filled with liquid nitrogen? Please don't berate me for this question, I know nothing about interactions between chemicals, I just know that the reactor is very hot and liquid nitrogen is very cold.

9) Do Nuclear plants not have water towers or large storage areas for emergency fresh water, so they can run for a couple days without having to resort to sea water?

10) Finally I keep reading that x amount of radiation is lethal, but I have yet to read anywhere what happens if you get a lethal dose. Like what would happen if someone walked into a room with lethal amounts of radiation and just stood there until they 'died' what would kill them?

1) Astronuc - You are so freakin smart!

I agree. Great moderator.

2) TCups - Nice forensic work, it was almost like reading a book. I must say though I was getting stressed out seeing all the work you have put into your posts, I could never do all that :)

I may not agree with all his theoroes but he is doing his part to keep this thread interestinng and focused on finding truth.

3) From the information we have currently, is it safe to assume that everything could have been prevented if the plant never ran out of power?

If there hadn't been a loss of power, if there hadn't have been a tsunami, if there hadn't been an earthquake, the event could have been prevented. It will take a long time to figure out where or when the last barrier to this accident failed.

4) If this happened in the states I would hope that we would be able to mobilize tractor-trailer sized generators & have them patched in within 8 hours?

There are two things going for the US plants. First is the response to the Station Blackout Rule which provided a short (4 or 8 hours in most cases) coping period for a total loss of offsite and onsite AC sources. Second in response to the 9/11 incident plants have added systems for remote cooling of the spent fuel pool and the reactor vessel. Plants have prepositioned pumps and ssupport equipment to perform this task without outside power.

5), Why would it take several days to run electrical connections from the grid back to the plant? Could you not just block off roads, fields etc. and just unspool a giant cable within a few hours?

The reason high tension lines have insulators on the towers is to prevent a short to earth. Remember Japan had an earthquake and a tsunami that disrupted roads, airports, etc.

6) Why do Nuclear plants have emergency hookups? Why not have 'ports' outside the reactor buildings for fire hoses to connect to that would shower the SFP with water? I understand that they need to have a closed system to prevent accidents, but if an accident does occur then they have no recourse it seems.

They do have such systems.

7) Again I saw some posts about not having the right generator types, 50 vs 60hz or not being able to splice into the system. Why would they not have an emergency hookup area for extra generators, batteries or external power lines? They could have all the transformers, cables, converters etc. to make connecting so much faster.

Allegedly this comes from assistance to electrify Japan after WWII. US helper in the northeast and used 60 hz. The south and western part of the island used 50 hz.

You can't just connect 50 hz to 60 hz with a transformer. It would require all the 60 Hz generators to be offline deepening the energy crisis already there. And then the motors and equipment that got the power would not be designed for that frequency.

8) Could someone design a system where when power is lost that the reactor vessel is continually filled with liquid nitrogen? Please don't berate me for this question, I know nothing about interactions between chemicals, I just know that the reactor is very hot and liquid nitrogen is very cold.

New designs for PWRs and BWRs incorporate systems for makeup and cooling that can operate without electrical power for days instead of hours. They use gravity fed makeup systems and natural convection flows.

9) Do Nuclear plants not have water towers or large storage areas for emergency fresh water, so they can run for a couple days without having to resort to sea water?

Yes. Plants have condensate storage tanks sufficient to manage the early response in an design basis emergency. If that is empty US plants would use fire protection systems, wells, lake or river water to continue cooling much as the Japanese used seawater.

10) Finally I keep reading that x amount of radiation is lethal, but I have yet to read anywhere what happens if you get a lethal dose. Like what would happen if someone walked into a room with lethal amounts of radiation and just stood there until they 'died' what would kill them?

High radiation causes radiation burns . Inhaled radioactivity tend to cook you from the inside out. Even with a smarter decision to leave the area and seek drastic medical treatment won't help if the "body burden" is sufficient to kill internal organs. Radiation kills the blood producing marrow in bones. Resistance to infection is destroyed by blood changes from radiation. Latent cancers from doses well short of lethal doses and may take years to kill you. The nuclear industry preaches ALARA (as low as reasonably acheveable) for exposures to workers and the public. The problem is that there may be no minimum threshold for adverse impacts on health. NO AMOUNT OF RADIATION IS SAFE.

Scary huh? Just remember that many things have much higher risks, driving an automobile, smoking, flying. Life is a balance of risks and consequences.

 

[shogun338]

Given the isotopes already found and their ratios, should we expect to be finding Sr-90 in the contaminated water/soil/air?

Aside from sharing the dubious distinction of both nations having been at the receiving end of America 's nuclear weapons, Japan and the Marshall Islands now share a second dubious distinction. The unleashed isotopes of concern from the damaged Japanese reactors - Iodine-131, Cesium-137 , Strontium-90 and Plutonium-239 - are well known to the Marshall Islanders living downwind of the testing sites at Bikini and Enewetak atolls in the central Pacific, following sixty-seven A- and H-bombs exploded between 1946-58. In fact, it is precisely these isotopes that continue to haunt the 80,000 Marshallese fifty-three years after the last thermonuclear test in the megaton range shook their pristine coral atolls and contaminated their fragile marine ecosystems. • Strontium-90 has a half life of twenty-eight years, is a chemical analog of calcium and is known as a "bone seeker"; Rongelap and the other downwind atolls have residual Sr-90 in their soils, groundwater and marine ecosystems. http://www.countercurrents.org/alcalay270311.htm

 

[NUCENG]

REGARDING THE SEQUENCE OF POWER LOSS

This is not consistent with what I have read and heard the last few weeks, which is:
1) Offsite power was lost at the time of the earthquake.
2) Emergency diesel generators worked properly for almost an hour, then these were disabled by the tsunami.
3) Battery back up power failed in a few hours time, and in less time that it was possible, under disaster conditions, before it was possible to truck in new generators and bring power back on line with them, although desperate attempts were made to do so.

Which scenario is correct? Would emergency diesel power have powered all the functions of the facility, including the fuel transfer machinery? Might the 9.0 quake have in some way disrupted the effort to return the fuel to the proper slot? Might the operators return the fuel rod to its proper slot then get the heck off the fuel handling machine as quick as possible, rush back to the control room, or to wherever their "disaster" station was, and in so doing, have left the mast grappled to the spent fuel rod assembly? This is not known.

REGARDING THE HANDLING OF FUEL, SPENT FUEL POOLS, AND TRANSFER CHUTES

There were two special flat bed trucks parked to the west of unit 3, one empty. I had heard but not confirmed that the implication was that older fuel rods from the SFP were to be loaded into casks for transfer to dry cask storage (or perhaps storage at the 7th SFP facility in wet storage?). I am not familiar with the technical aspect of those sorts of transfer.

As for the "cattle" transfer chute, I believe I understand its size, location and function. In fact, there appear to be two of these -- one at the interface of the reactors upper primary containment, above the level of the drywell cap, and a second between the main SFP and a smaller pool, which, I believe, is used for the cask transfer functions above (not certain of that). There were two potential problems related to the "cattle" chute, neither having anything to do with fuel being in the process of moving through the chute.

1) the seals on the gate(s) between the drywell containment, chute, and SFP are pneumatic and the pressure in the seals is maintained by electric pumps. If the seals are not properly pressurized, it is possible for water to leak from the SFP into the primary (drywell) containment above the level of the drywell cap, but below the "plug" that covers the reactor access, and
2) there are reports that the seals on the drywell cap itself may fail under as little as 2 ATM pressure from the primary drywell containment surrounding the reactor pressure vessel.

The other chute connects a second, smaller pool to the SFP. I have no information about a gate and seal on that chute, but doubt there would be as both these pools are open to air above and share a common water level. The connecting chute is only a few meters deep, however.

I am not an engineer and have no first-hand knowledge, but these issues and potential problems have been discussed here in the past weeks in some detail.

One implication, however, is that there is the potential, under a complete loss of power to have failure of the chute seals, and, possibly, abnormally high pressures within the drywell containment, thus creating a potential pathway for leakage of hydrogen or the explosive release of hot gasses from the primary drywell containment, through the drywell cap seals and through the chute gate seals, at least in theory.

Any solid information or additional relevant comments are appreciated. We are all just trying to understand what happened and why.

PS:
Rod Stewart had it right: "Every picture tells a story"
Let's hope it doesn't turn into a John Lee Hooker blues tune: "Boom, Boom, Boom, Boom"
good night.

Your sequence is correct. My bad. I honestly don't remember if the FHM is powered by essential (Emergency Diesel ) power. If we have any experienced BWR operators on the forum, they would know. If it was, my discussion of the plant response is correct and they would have placed the bundle into the pool before evacuating the refuel floor.

If it wasn't powered from the diesels, the FHM is designed to fail as-is. It won't unlatch and drop the rod. The operators have manual backups for lowering or hoisting the load (ropes and pulleys), but it is possible they would leave it as-is in hopes of restoring power. In that case the FHM could have only been over the Spent Fuel Pool of the Cask pool, If it were over the cask pool wjth a cask installed there could have been a few relatively old (several years since discharge) bundles in the cask with low heatup rates. (In dry storage the air is sufficient to cool the fuel.) If water level was lost throughout the fuel and cask pools these bundles would still have whatever water was in the cask. Their heatup and initiation of Zirc water reaction would have been longer than freshly discharged fuel. This explosion would have been delayed and relatively smaller than a larger number of fuel rods in the fuel pool or reactor containing fresh fuel. Rule of thumb for heatup of a uncovered rod freh from the reactor is one degree per second.

One other item to consider, the refueling mast is designed to hoist a single fuel bundle. In cases where a control rod blade is stuck or a bundle needs to be unstuck from the support plate, they have to add additional lifting to get them free, It is not designed to accelerate that load to a velocity sufficient to reach several hunded meters in altitude. I've seen it up close. It just doesn't look possible.

There is a gate beteen the spent fuel pool and the cask pool. This allows the cask pool to be drained so the cask can be dryed and seal welded. There is always at least 6 feet of water or more over the top of a fuel bundle while it is being moved. That includes through the chute and in the cask. With the fuel pool at normal levels the bundles in the reactor, spent fuel pool, or cask are much deeper than that.

 

[jlduh]

Nuceng said:

Once again, you can design systems to be foolproof. It is unfortunately not possible to make them damnfoolproof

Yes, but damnfool can design foolproof systems. Which is sometimes even worse.

That's all the tragedy of this Fukushima plant, when we look at EDG layout, probably global platform height regarding to historical tsunami runups, and many other aspects.

Designing things is as difficult as operating them. And I've seen in my career as many mistakes in both sides. So I'm always kind of sceptic when "titanic like" assertions are done before hand saying "It's not possible", or "the probability is so low that there is no real risk". I think this should be an other lesson to reassess that kind of thinking.

Human brain is not that good to anticipate complex combinations of multiple factors (design factors and operational factors). It's good enough make it believe so, but not that good in fact. It is better meanwhile when there is a close loop between risk and consequence for him. In WW2, the accident rate for not properly opened parachutes was very high until somebody decided that the ones who is preparing the parachute will be the one who will jump from the plane. That's always the case now everywhere. This relates well with my point below.

Life is a balance of risks and consequences

Not untrue, but... that is what bankers were saying too. The problem is that very often, in both cases, the ones who take the risks are not the ones who get the main consequences. The balance is very often shifted this way (even if the average is "balanced").

Leaving for 2 weeks without any connection available, this will be my last "political" thought here for some time, I'll read you again in two weeks from now, and I'll be maybe 100 pages behind!

Let's hope this damn situation will not worsen.

 

[shogun338]

The operator of Japan's stricken nuclear plant said on Saturday it had found radioactive water leaking into the sea from a cracked concrete pit at its No.2 reactor in Fukushima.

Japan's nuclear watchdog said TEPCO is preparing to pour concrete into the pit to stop the leak.

 

[shogun338]

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

1.Current Situation

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

The Unit 1 condenser is full. In preparation for transferring water in the basement of the turbine building to the condenser, water in the condenser storage tank is being transferred to the suppression pool surge tank since 31 March, 03:00 UTC. Water in the trench was transferred to a water tank at the central environmental facility process main building. In order to prepare for removal of the water from the turbine building basement in Unit 2, pumping of water from the condenser to the suppression pool water surge tank started at 07:45 UTC 29 March. For Unit 3 pumping of water from the condenser to suppression pool water surge tank was started at 08:40 UTC March 28 and was completed at 23:37 UTC on 30 March.

For Unit 1 fresh water has been continuously injected into the Reactor Pressure Vessel (RPV) through the feed-water line at an indicated flow rate of 8 m3/h using a temporary electric pump with diesel backup. In Unit 2 fresh water is injected continuously through the fire extinguisher line at an indicated rate of 8 m3/h using a temporary electric pump with diesel backup. In Unit 3 fresh water is being injected continuously at about 7 m3/h into the reactor core through the fire extinguisher line using a temporary electric pump with diesel backup.

The indicated temperatures at the feed water nozzle of the RPV and bottom of RPV on Unit 1 are stable at 256 °C and 128 °C respectively. There is a slight decrease in RPV and Drywell pressures. The indicated temperature at the feed water nozzle of the RPV of Unit 2 is stable at 165 °C. The temperature at the bottom of the RPV was not reported. Indicated Drywell pressure remains at atmospheric pressure. The indicated temperature at the feed water nozzle of the RPV in Unit 3 is stable at 101 °C and at the bottom of RPV is also stable at 112 °C. Indicated Drywell pressure remains slightly above atmospheric pressure. The validity of the RPV temperature measurement at the feed water nozzle is still under investigation.

The pumping of water into the Unit 1 Spent Fuel Pool by concrete pumping truck was started at 04:03 UTC on 31 March. Fresh water was sprayed to the spent fuel pool at the Unit 3 by the concrete pump on 31 March and to the spent fuel pool on Unit 4 on the 1st April.

Units 5 and 6 remain in cold shutdown

2. Radiation Monitoring

On 31 March, deposition of iodine-131 was detected by the Japanese authorities in 8 prefectures, and deposition of cesium-137 in 10 prefectures. In these prefectures where deposition of iodine-131 was reported, on 31 March, the range was from 29 to 1350 becquerel per square metre. For caesium-137, the range was from 3.6 to 505 becquerel per square metre. In the Shinjyuku district of Tokyo, the daily deposition for iodine-131 was 50 becquerel per square metre and for cesium-137 it was 68 becquerel per square metre. No significant changes were reported in the 45 prefectures in gamma dose rates compared to yesterday. As of 28 March, recommendations for restrictions on drinking water are in place at two locations in the Fukushima prefecture and restrictions continue to apply for infants only. The IAEA monitoring team made additional measurements at 9 locations West of Fukushima-Daiichi NPP. The measurement locations were at distances of 30 to 58 km from the Fukushima nuclear power plant. The dose rates ranged from 0.4 to 2.3 microsievert per hour. At the same locations, results of beta-gamma contamination measurements ranged from 0.01 to 0.49 Megabecquerel per square metre. The other team who had made monitoring measurements in Tokyo during the last week, has finished its activities.

Since our written briefing of yesterday, significant data related to food contamination was reported on 31 March by the Japanese Ministry of Health, Labour and Welfare. Reported analytical results covered 2 samples taken on 15 March and 109 samples from 27-31 March. Analytical results for 98 of the 111 samples for various vegetables, spinach and other leafy vegetables, fruit (strawberry), seafood, various meats (beef, chicken and pork) and unprocessed raw milk in eight prefectures (Chiba, Fukushima, Gunma, Ibaraki, Kanagawa, Niigata, Tochigi, and Tokyo), indicated that iodine-131, caesium-134 and caesium-137 were either not detected or were below the regulation values set by the Japanese authorities. However, it was reported that analytical results in Chiba, Fukushima, Ibaraki and Tochigi prefectures for the remaining 13 of the total 111 samples for spinach and other leafy vegetables, parsley and beef indicated that iodine-131 and/or caesium-134 and caesium-137 exceeded the regulation values set by the Japanese authorities.

The following restrictions are in place (Ministry of Health, Labour and Welfare Press Releases 21 and 23 March 2011):

Fukushima: Distribution and consumption of leafy vegetables (including broccoli, cabbage, cauliflower, kakina, komatsuna and spinach), turnip and unprocessed raw milk. Ibaraki: Distribution of spinach, kakina, parsley and unprocessed raw milk.
Gunma: Distribution of spinach and kakina.
Tochigi: Distribution of spinach and kakina.

The Joint FAO/IAEA Food Safety Assessment Team has completed its mission and presented its report to the Japanese Cabinet Office, Ministry of Foreign Affairs, Ministry of Health, Labour and Welfare and the Ministry of Agriculture, Fisheries and Forestry on 31 March. The IAEA members of the Team are returning to Vienna today.

The Agency, in agreement with the Japanese government, will dispatch two reactor experts to Japan. They will hold meetings with the Nuclear Safety Commission, NISA, TEPCO and other Japanese counterparts from Monday 4 April onwards. The objective of this visit is to exchange views with Japanese technical experts and to get first-hand information about the current status of reactors at Fukushima Daiichi, measures being taken and future plans to mitigate the accident.

 

[shogun338]

From TEPCO .

*We found a puddle of water at the main building of the centralized
environmental facility process. We analyzed and detected approximately
1.2 x 101Bq/cm3 of radioactivity in full dose in the Controlled Area and
2.2 x 101Bq/cm3 in full dose in the Non-Controlled Area on March 29.

*A barge of the U.S. Forces with fresh water to be used to cool down
reactors etc. was towed by a ship of Maritime Self-Defense Force and at
3:42 pm on March 31st 2011, came alongside the pier. At 15:38, April 1st,
we started to replenish the fresh water with filtrate tanks.

*At 11:35 am, April 1st, a worker fell into the sea while stepping into
the ship from the pier during the hose laying work of the barge. Other
crew immediately rescued the worker. While no injury or contamination was
confirmed, whole body counter will be implemented to check the
contamination inside the body just in case.

*From 3:00 pm, April 1st, we started spraying inhibitor in order to
prevent diffusion of radioactive materials. This attempt was conducted on
a trial basis at the mountain side area of the common spent fuel pool in
the range of 200m2. The spraying finished at 4:05 pm.

*Monitoring posts (no.1 to no.8) which were installed around the site
boundary have been restored. We will continue monitoring the measured
value and make announcements on those values accordingly.

*We will continuously endeavor to securing safety, and monitoring of the
surrounding environment.

 

[shogun338]

- Presence of 2 TEPCO employees at the site is not confirmed on March
11th.
- On March 24th, it was confirmed that 3 workers from cooperative
companies who were in charge of cable laying work in the 1st floor and
the underground floor of turbine building were exposed to the radiation
dose of more than 170 mSv. 2 of them were confirmed that their skins on
legs were contaminated. After they were decontaminated, since there was
a possibility of beta ray burn injury, they were transferred to
Fukushima Medical University Hospital. The third worker was also
transferred to Fukushima Medical University Hospital on March 25th.
Later, the 3 workers were transferred to National Institute of
Radiological Sciences in Chiba Prefecture. They all left the hospital
on March 28th. Regarding this event, TEPCO has reported to the related
government ministries and agencies on measures to be taken to assure
appropriate radiation dose control and radiation exposure related
operations.
We will inform the related parties of countermeasures and continue to
take all possible measures to future management.

Others
- We measured radioactive materials (iodine etc.) inside of the nuclear
power station area (outdoor) by monitoring car and confirmed that
radioactive materials level is getting higher than ordinary level. As
listed below, we have determined that specific incidents stipulated in
article 15, clause 1 of Act on Special Measures Concerning Nuclear
Emergency Preparedness (Abnormal increase in radiation dose measured
at site boundary) have occurred.
· Determined at 4:17 pm Mar 12th (Around Monitoring Post 4 )
· Determined at 8:56 am Mar 13th (Around Monitoring Post 4 )
· Determined at 2:15 pm Mar 13th (Around Monitoring Post 4 )
· Determined at 3:50 am Mar 14th (Around Monitoring Post 6 )
· Determined at 4:15 am Mar 14th (Around Monitoring Post 2 )
· Determined at 9:27 am Mar 14th (Around Monitoring Post 3 )
· Determined at 9:37 pm Mar 14th (Around main entrance )
· Determined at 6:51 am Mar 15th (Around main entrance )
· Determined at 8:11 am Mar 15th (Around main entrance )
· Determined at 4:17 pm Mar 15th (Around main entrance )
· Determined at 11:05 pm Mar 15th (Around main entrance )
· Determined at 8:58 am Mar 19th (Around MP5)
From now on, if the measured figure fluctuates and goes above and below
500 micro Sv/h, we deem that as the continuous same event and will not
regard that as a new specific incidents stipulated in article 15,
clause 1 of the Act on Special Measures Concerning Nuclear Emergency
Preparedness (Abnormal increase in radiation dose measured at site
boundary) has occurred. In the interim, if we measure a manifestly
abnormal figure and it is evident that the event is not the continuous
same event, we will determine and notify.

- The national government has instructed evacuation for those local
residents within 20km radius of the periphery and evacuation to inside
for those residents from 20km to 30km radius of the periphery, because
it is possible that radioactive materials are discharged.
- At around 10:37 am March 21st, water spraying to common spent fuel pool
and finished at 3:30 pm (conducted by TEPCO).
- At around 3:37 pm, March 24th, electricity supply to common spent fuel
pool has started from external power source. At around 6:05 pm, fuel
pool cooling pump was started to cool the pool.
- We found no signs of abnormal situation for the casks by visual
observation during the patrol activity. A detailed inspection is under
preparation.

 

[ulvy]

Here are some high resolution photos taken from a drone.

http://cryptome.org/eyeball/daiichi-npp/daiichi-photos.htm

and here is a video

 

[|Fred]

Thank you , those HD pics were posted about 20 pages down :)

Here is a photo of the pit allegedly leaking to the sea for Unit 2
I was not able to locate it on the plant.

 

[shogun338]

Thank you , those HD pics were posted about 20 pages down :)

Here is a photo of the pit allegedly leaking to the sea for Unit 2
I was not able to locate it on the plant.

Japan’s nuclear regulator said that workers discovered a crack about eight inches wide in the pit, which lies between the No. 2 Reactor and the sea and holds cables used to power seawater pumps. http://www.nytimes.com/2011/04/03/world/asia/03japan.html?_r=1&src=twrhp

 

[AtomicWombat]

Thank you , those HD pics were posted about 20 pages down :)

Here is a photo of the pit allegedly leaking to the sea for Unit 2
I was not able to locate it on the plant.

I tried to find it on Google Earth but the resolution is not high enough.

Interestingly Google Earth already has updated its images to post-reactor building 4 explosion.

 

[shogun338]

Tokyo Electric Power is looking to send radiation-hardened robots into the wrecked Fukushima Daiichi nuclear power plant, but obstacles literally stand in the way of their use. http://www.pcworld.com/article/223852/debris_prevents_robots_from_entering_stricken_nuclear_plant.html

 

[Borek]

NO AMOUNT OF RADIATION IS SAFE.

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.

 

[AntonL]

here is a cam picture recorded at 12:00 (japan time) today
[PLAIN]http://pointscope01.jp/data/f1np/f1np1/pic/20110402160059.jpg

 

[clif]

First post, thanks to everyone who has already taught me so much about the tragedy in Japan.

I was not able to locate it on the plant.

As for the location for the pic.

If I am right the place the worker is pointing to is where I located the arrow.

The Tower is the one I circled, and the small Building in the background Behind the railing, is the one I circled.

that is the best location I could come up with.

 

[Borek]

First post, thanks to everyone who has already taught me so much about the tragedy in Japan.

I was not able to locate it on the plant.

As for the location for the pic.

If I am right the place the worker is pointing to is where I located the arrow.

The Tower is the one I circled, and the small Building in the background Behind the railing, is the one I circled.

that is the best location I could come up with.

Clif, you need to be more precise - with almost 2500 posts in the thread we have no idea what you are referring to.

 

[Borek]

There is an are in Africa which has a very unusual distribution of Uranium isotopes, It is deficient in the portion of U235 found in ores in the rest of the world. It has been suggested that at some time in the distant pass the Earth created a natural reactor due to fluctiations in the water table it depleted the U235. The area is several hundred square miles.

I guess you mean http://en.wikipedia.org/wiki/Oklo

 

[clif]

I was referring to the post #2479 about the photo about the water leak.

 

[NUCENG]

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.

Sorry, I miscommunicated. I was trying to emphasize how much the nuclear power industry tries to minimize any exposure to workers or the public.

Eating fatty foods in excess allegedly causes obesity, heart disease and death. If I eat 10 pounds of chicken fried bacon for every meal, I expect it might cause me a problem. I'm not sure if that damage happens with one pound of chicken fried bacon over a year. But I can be reasonably sure that trying it once won't kill me.

Regulators set limits on radiation exposure based on best understanding of where any changes can be detected. Keeping releases as low as reasobly achievable has resulted in a history of operation that is hard to distinguish from background.

I know we are all focusing on Fukushima. We have seen some injuries. But two people at the site were reportedly washed away during the tsunami and a crane operator was killed. Compare that with possibly 20,000+ dead in Japan from the natural disaster. That is smaller than the death toll on US highways every year. And let,s not even estimate the death toll from malaria and diseases across the world for which cures exist.

 

[geb.es]

There is one thing in the footage of the reactor 3 explosion that I have not seen mentioned. There seems to be a huge recoil component going horizontally northbound. Look at this video, seconds 16 to 30. Apart of the vertical ballistic effect there is a cloud of dust/vapor moving very quickly and very far to the left. By 26'' we cannot even see the leftmost antenna, then the antenna reappears but in the base of it we still see dust moving northbound. Any explanations?

https://www.youtube.com/watch?v=iSFQ11_Y2dY

 

[AtomicWombat]

A report using two different risk models to calculate the excess cancers likely in residents within 100km and 100 to 200 km from Fukushima. Both models assume residents not yet evacuated remain where they are for the next year. Many assumptions go into both models (ECRR risk model & the ICRP model) and they produce widely varying results, indicating the science of radiation risk at low-moderate doses is imprecise.

http://www.fairewinds.com/sites/default/files/fukuhealthrept.pdf"

The conclusions are:

"1. The ECRR risk model has been applied to the 3 million people living in the
100km radius of the Fukushima catastrophe. Assuming these people remain
living there for one year the number of excess cancers predicted by the method is
approximately 200,000 in the next 50 years with 100,000 being diagnosed in the
next 10 years. If they are evacuated immediately, the number will fall by a
significant amount. For those 7 million living between 100km and 200km from
the site, the predicted number of cancers is slightly greater with 220,000 extra
cancers in the next 50 years and about 100,000 being expressed in the next ten
years. These predictions are based on the ECRR risk model and also the findings
of cancer risk on Sweden after the Chernobyl accident.

2. The ICRP model predicts 2838 extra cancers in the 100km population. The
eventual yield will therefore be another test of the two risk models.
It is recommended that populations living within the 100km zone to the North
West of the site are immediately evacuated and the zone is made an exclusion
zone.

3. Calculations based on official gamma dose rates published by the Japanese
Ministry MEXT can be used to back calculate surface contamination at the
positions of the measurements using accepted scientific methods. The results
show that the IAEA reports have significantly under reported the contamination
levels.

4. It is recommended that urgent attention is given to making isotope specific
ground contamination measurements.

5. It is recommended that populations living within the 100km zone to the North
West of the site are immediately evacuated and the zone is made an exclusion
zone.

6. The ICRP risk model should be abandoned and all political decisions should
be made on the basis of the recommendations of the European Committee on
Radiation Risk www.euradcom.org This is the conclusion of the eminent
radiation risk experts who signed the 2009 Lesvos Declaration

7. Investigation and legal sanctions should be brought against those who
knowingly held back data from the public

8. Investigation and legal sanctions should be brought against those minimising
the health effects of this event in the media."

The author has a point, but he also has an axe to grind:
http://en.wikipedia.org/wiki/Christopher_Busby"

 

[AtomicWombat]

There is one thing in the footage of the reactor 3 explosion that I have not seen mentioned. There seems to be a huge recoil component going horizontally northbound. Look at this video, seconds 16 to 30. Apart of the vertical ballistic effect there is a cloud of dust/vapor moving very quickly and very far to the left. By 26'' we cannot even see the leftmost antenna, then the antenna reappears but in the base of it we still see dust moving northbound. Any explanations?

https://www.youtube.com/watch?v=iSFQ11_Y2dY

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.

 

[AtomicWombat]

First post, thanks to everyone who has already taught me so much about the tragedy in Japan.

I was not able to locate it on the plant.

As for the location for the pic.

If I am right the place the worker is pointing to is where I located the arrow.

The Tower is the one I circled, and the small Building in the background Behind the railing, is the one I circled.

that is the best location I could come up with.

Looks about right clif.

 

[Borek]

Many assumptions go into both models (ECRR risk model & the ICRP model) and they produce widely varying results, indicating the science of radiation risk at low-moderate doses is imprecise.

Lies, damned lies and statistics?

 

[geb.es]

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.

You are right, that explains the disappearance and reappearance of the stack (what I called the antenna); but what I wanted to draw attention to is the dust cloud moving rapidly northbound, reaching past reactor 1. I would like to see if this fits with TCups "SPF acting as a cannon" hypothesis. Here is a wild guess:

As TCups says, the blast originates in the reactor or at least in the containment vessel. Pressure from it escapes in two opposite directions, to the SF pool(s) and to the utility pool. The SFP acts as a cannon shooting vertically, carrying water, fuel rods, and FHM with it, while the utility pool's north wall collapses and sends a blast horizontally towards the north. This also explains the heavy damage in the small building north of building 3. (Although that damage can also be explained by debris falling there, together with the FHM).

Does that make any sense?

 

[AtomicWombat]

Lies, damned lies and statistics?

Surely too my lives are at stake to take that attitude. This form of modelling is the best means available for estimating radiation risk.

Reading Busby's report, he notes that the ICRP model was developed based on the effects on long-term survivors of Hiroshima and Hagasaki.

"This method cannot apply to internal doses from radioactive substances, called radionuclides, which have been inhaled or ingested in food or water. ... The ICRP method annot either be applied to inhaled or ingested hot particles, which are solid but microscopic and can lodge in tissue delivering high doses to local cells. There is a great deal of evidence that exposure to internal radionuclides is up to 1000 times more harmful than the ICRP model concludes."

"This method [the ECRR model] was applied to the results of the study of Tondel et al 2004 in Sweden who found 11% increase for 100kBqm-2 surface contamination. It almost exactly
predicted what these researchers found. These researchers carried out regressions to correlate cancer increases with area contamination by Cs-137 and other radionuclides from Chernobyl. The error factor relating the ICRP risk model, which employs external radiation, was upwards of 600-fold."

So the ICPR method drastically underestimated cancer rates from Chernobyl because it neglects the effects of inhaled or ingested radionuclides & hot particles.

 

[AntonL]

Lies, damned lies and statistics?

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

 

[AntonL]

TEPCO published some pics today to celebrate US barge docking with freshwater. It was also reported that one man fell into the water during the docking procedure.
(I now read Japan are asking USA to use this barge to store radioactive water after freshwater has been used)

But look at the last photo - massive ground shifting took place during earthquake - remember this is fill on bedrock.

 

[Borek]

Surely too my lives are at stake to take that attitude. This form of modelling is the best means available for estimating radiation risk.

Agreed, and I am not against trying to model the risk. However, when models give results different by orders of magnitude it is obvious there is something wrong with either one or both approaches. And - as with every loaded subject - experience shows that people involved will do everything to twist the statistics till it becomes damned lies; that's all I was referring to.

Somehow I am reluctant to accept these high numbers. If the effects were really that high they should be easy to see in general demographic statistics (I am thinking about Chernobyl here) - but it seems like they are not higher than the noise. You can't hide additional million deaths, it should be visible in the population growth rate.

 

[AntonL]

The problems Tepco have in moving the basement and trench water are clearly indicated in below slide: