'Radiation equivalent to 400 times the level to which people can safely be exposed detected'

[Bluebear]

The crisis at the quake-hit Fukushima No. 1 nuclear plant reached a critical phase Tuesday with radiation feared to have leaked after apparent hydrogen blasts at two more reactors, triggering growing fears of widespread contamination.

Prime Minister Naoto Kan urged people living between 20 and 30 kilometers of the plant to stay indoors, after radiation equivalent to 400 times the level to which people can safely be exposed in one year was detected near the No. 3 reactor in the plant.

Residents within a 20-km radius have already been ordered to vacate the area following Saturday's hydrogen blast at the plant's No. 1 reactor.

''The danger of further radiation leaks (from the plant) is increasing.'' Kan warned the public at a press conference, while asking people to ''act calmly.''

http://english.kyodonews.jp/news/2011/03/78123.html

"Please do not go outside. Please stay indoors. Please close windows and make your homes airtight," Chief Cabinet Secretary Yukio Edano told residents in the danger zone. "Don't turn on ventilators. Please hang your laundry indoors."

"These are figures that potentially affect health. There is no mistake about that," he said.

http://news.yahoo.com/s/ap/ap_on_bi_ge/as_japan_earthquake

:(

[CoffeeCat]

1. I appreciate you posting this Bluebear...

This is very informative.

It is very difficult to assess exactly what is happening. One minute, we read an article that gives
us hope that the melting down is contained. Then, another very disturbing article is revealed that
makes the situation sound dire. I think the time difference between the US and Japan creates another
challenge.

It's hard to know what is going on--and unfortunately, all we can do is keep reading and hope for the best.

Thanks for posting. :)

[nadinbrzezinski]

2. The second plant, that is plant 2, fukushima 2

they have brought those reactors under control. They are separate from number one... the ones we all have been following.

Those have not gotten better.

[Hannah Bell]

3. I believe this is from the presser about 4-5 hours ago?

[Matariki]

4. And then what?

I mean what to do after making home airtight?

[nadinbrzezinski]

6. You stay in and hope it works

the walls wil provide some shielding, as in limited. Alpha and beta will stop... Gama... not so much.

Stil it is procedure. The increase in cancer clusters will be amazing.

[Journeyman]

5. What's the half life of "hang your laundry indoors"? . . .

[nadinbrzezinski]

7. Why did you just make me laugh?

[divvy]

8. Relief Valve

Now, there is a report of a stuck open relief valve. This has the same effect as a small LOCA. That RX leak uncovered the core. Relief valves have a history of doing that (sticking open). It was only a huge problem, because the plants ability to offset it with water has been severely degraded. They have to either get more water... e.g., running HPCI if they can. As far as I know, they still don't have low pressure cooling systems. They need AC power for that! The relief valve may close by trying to exercise it (not much chance of that working) or it will close at about a RX pressure of 80 psig. Does it ever end? These emergency systems were not really intended to be used many times or for days. If they have cycled those relief valves a dozen times or more, they are worn out. Sticking open is not totally unexpected. if they can't keep the core covered, the last step is to intentionally drain the vessel... And flood containment with sea water. Hopefully, they can recover the core quickly. The TMI core was uncovered for a few hours. The core geometry can be maintained with 2/3rd core coverage. Some, either small amount or small time duration, can be tolerated

[divvy]

9. Navy Flight through the plume

I hear now that the navy guys flew through a nuclear plume. When the reactor is vented, it is vented through a filtration system, SBGTS, and blown up through the chimneys onsite. You can't see the plume, Luke a fossil fuel some stack. He purpose of the chimney is o elevate he release where it will be dispersed over a large area. Normal dose rates in he plume are very low... this is not a normal release. The Navy moving away was unnecessary... They just need to e careful where they fly and don't fly downwind of the plant. Being further away won't help aircraft crews. If the boats are seeing high radiation, well that would imply the worst has happened. I heard a report that a pump ran out of fuel causing he problem at U2. I am not sure what they are using for injection... Could be they got an emergency generator running... they could be using a fire water pump to pump sea water... Or they could have "Jerry rigged" a temporary power supply running on diesel. Just don't know. The fuel tanks for the Emergency diesels would need refueling by now. Operators could probably pump fuel from tanks for unused diesels. I can't really describe the stresses those operators are under. To say their lives are at risk is stating the obvious. The main control room for a nuclear plant is maybe 600-900 square feet packed solid with control panels and computers. At the moment they lost the emergency generators and off site power... The overhead lights blinked and came on eerily dim. All the electrical panels went dark except one lonely alarm panel that says "AC Power Failure." I would have different words for the alarm, but that wouldn't have been very professional. The plant I was at was a BWR 4/Mark I. Our plant was different to some extent, though. We had our diesels inside the turbine and reactor buildings. I am not sure they would have survived a Tsunami, since they certainly are not in water tight compartments. I haven't seen Turbine Buildings at the Japanese site.

[dgibby]

17. The USS George Washington was in port for repairs,

detected radiation in Yokosuka. They weren't flying through anything. If the Skipper of a nuclear powered carrier decides to move his group to avoid radiation, that tells this Navy Vet all I need to know about how serious the situation is. I applaud the Navy for having the sense to take extra precautions to protect their personnel. No sense in taking any unnecessary risks.

[divvy]

28. I just got this

from rsoe.com email alert - 7th Navy Fleet moving away from radiation

The U.S. 7th Fleet has temporarily repositioned its ships and aircraft away from the Fukushima Dai-Ichi Nuclear Power Plant after detecting low level contamination in the air and on its aircraft operating in the area. The source of this airborne radioactivity is a radioactive plume released from the Fukushima Dai-Ichi Nuclear Power Plant. For perspective, the maximum potential radiation dose received by any ship's force personnel aboard the ship when it passed through the area was less than the radiation exposure received from about one month of exposure to natural background radiation from sources such as rocks, soil, and the sun. The ship was operating at sea about 100 miles northeast of the power plant at the time. Using sensitive instruments, precautionary measurements of three helicopter aircrews returning to USS Ronald Reagan after conducting disaster relief missions near Sendai identified low levels of radioactivity on 17 air crew members. The low level radioactivity was
easily removed from affected personnel by washing with soap and water. They were subsequently surveyed, and no further contamination was detected. As a precautionary measure, USS Ronald Reagan and other U.S. 7th Fleet ships conducting disaster response operations in the area have moved out of the downwind direction from the site to assess the situation and determine what appropriate mitigating actions are necessary. We remain committed to our mission of providing assistance to the people of Japan.

This confirmation came much later in the day. I posted it in case you had not seen it.

[dgibby]

29. Thanks. Your posts are very detailed

and very informative. I had seen that, but didn't hear about the Geo. Washington until very late last night. I'm still glad the carrier group repositioned. If that #4 reactor, which is on fire once again, goes, all bets would appear to be off.

I was just watching Jenk on MSNBC, and he had a reactor specialist on, who says the 50 people who stayed behind are real heroes and will probably die as a result of their decisions. So very, very sad.

[divvy]

10. Barriers that safeguard the public

Here are the barriers that safeguard the public. 1) Cladding on the fuel. Large scale fuel failure has occurred at all 3 plants. Radioactive sampling around the plant would confirm this by the types of radiation contamination found. The presence of a lot of hydrogen exploding in buildings is indirect evidence that clad melted. Uncovering th core would cause extensive damage to he core. 2) The reactor vessel. At least 1 plant was reported to have a coolant leak. Another plant may have a stuck open relief valve. 3) the primary containment vessel (drywell) and the valves to isolate it. Primary containment was really lost with the emergency diesels. Nuclear plants have 2 separate and independent emergency A/C systems ( ESS I and II). There are redundant isolation valves in the leak pathes from the primary containment that are powered from each division. Each division is powered from different emergency generators. No A/C power, no primary containment. The containment vessel is there, but it is not leak tight, like it is supposed to be. Valves that should be closed aren't. 4) the secondary containment. This is the reactor building that blew up at 2 Units. That's it! All the barriers to a release are degraded. All these Units are operating way beyond where we can say for certainty what will happen. The core that is uncovered is probably exposing the Operators at the plant to large doses of radiation. I hope they have relief workers that can cycle in and out relieving the on duty crews and prevent lethal doses. We have at least 3 TMI's at the same site. I think it will be worse than TMI, because TMI was able to restore virtually all of their systems once they figured out their human errors. These plants don't seem to be getting their systems back. They need external A/C power. The last gasp is to drain the vessel and flood containment. They need to look at the containment configuration to see if any valve failures would prevent the flooding. They have been putting sea water into the reactor... They would have to switch to filling the containment... And that would require some improvising. Today, government officials are not ruling out anything... Yesterday, everything was under control. These politicians should just let the engineers talk. These plants are in a status we would classify as a General Emergency.

[divvy]

11. Spent fuel pools

You haven't heard a word out of any spokespeople and expert commintators about spent fuel pools and the plants that were already shutdown prior to the event, but have no AC power. None of these plants are safely shutdown until AC power is restored to vital cooling systems. The spent fuel pools are stainless steel sheet lined concrete structures. At least some have had the roof fall into them. Without any cooling and filthy water and the secondary containments gone, you will be seeing increased radiation coming from these pools. Radioactively contaminated water is evaporating from the pool surface. I suppose it is possible for an exploding building adjacent to a pool to damage it. I doubt it, though. I certainly hope not. I don't know what is going on now. I think they have evacuated all but the most essential workers due to the elevated dose rate. I hope they are still attempting to mitigate the ramifications of the core melt. Barbara, there is no chance of radiation reaching other countries in serious levels, as far as I know. The spread radiation may be detectable, but it will be far less than what would cause risk to humans. Even given that this is the second worst nuclear accident in history, I don't think there will be any loss of life, or at least that is my hope. The ones most at risk are the operators trying to terminate the accident. Worst case -- The only events that would change my prediction above - 1) rupture of a spent fuel pool or 2) rupture of the bottom of the reactor vessel and containment in a Unit due to core melt. Best case -- The events at these plants will not get a whole lot better until they restore AC power and get an RHR loop running to cool suppression pool and the core... And the LPCI mode of RHR injecting into the vessel. If this equipment in the basement of the RX building has been irreparably damaged, they need portable equipment installed to do the same thing. I haven't heard anything saying this is being done. Maybe it isn't possible.

[divvy]

12. Burning fuel

I am trying to think of what could cause a fuel pool to burn. 400 millisievert is 40 Rem/ hr. OMG! My guess is that the Unit was refueling... They probably had offloaded some hot fuel into the storage pool. There has been no refuel pool cooling since the event started. You need AC power. The clad must have gotten hot enough to start melting the cladding. That generates the hydrogen. I told you! These shutdown plants are not safe. They should start dumping fire water into the pool... Just let the water overflow. You can't stop the hydrogen generation unless you can cool off the water. Normally, there are temperature alarms to keep the fuel pool below about 140degreesF. They don't work. I bet the temp is way over that now with hydrogen burning on the surface. This is the highest reported dose rate yet... And from the "shutdown" plant. Glad to hear they got the fire out... Now get that pool cooled down! ... Or it will re-ignite.

[divvy]

13. Fire confirmed

Japan Earthquake Update (15 March 2011, 06:15 CET)

Japanese authorities informed the IAEA that there has been an explosion at the Unit 2 reactor at the Fukushima Daiichi plant. The explosion occurred at around 06:20 on 15 March local Japan time.

Japanese authorities also today informed the IAEA at 04:50 CET that the spent fuel storage pond at the Unit 4 reactor of the Fukushima Daiichi nuclear power plant is on fire and radioactivity is being released directly into the atmosphere.

Dose rates of up to 400 millisievert per hour have been reported at the site. The Japanese authorities are saying that there is a possibility that the fire was caused by a hydrogen explosion.

The IAEA is seeking further information on these developments.

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

[divvy]

14. General Mark 1 layout

[divvy]

15. TEPCO press release

Press Release (Mar 15,2011)
Damage to the Unit 4 Nuclear Reactor Building at Fukushima Dai-ichi Nuclear Power Station


At approximately 6:00am, a loud explosion was heard from within the
power station. Afterwards, it was confirmed that the 4th floor rooftop
area of the Unit 4 Nuclear Reactor Building had sustained damage.

After usage, fuel is stored in a pool designated for spent fuel.

Plant conditions as well as potential outside radiation effects are
currently under investigation.

TEPCO, along with other involved organizations, is doing its best to
contain the situation. Simultaneously, the surrounding environment is
being kept under constant surveillance.


http://www.tepco.co.jp/en/index-e.html

[divvy]

16. Prior TEPCO press release

Press Release (Mar 15,2011)
Plant Status of Fukushima Daini Nuclear Power Station (as of 7:15 am Mar 15th)


At 7:15am, Mar 15th, Unit 4 achieved reactor cold shutdown. Accordingly,
all the units in Fukushima Daini Nuclear Power Station have achieved
reactor cold shutdown.

Unit 1 (shut down at 2:48pm on Mar 11th)
- Reactor is shut down and reactor water level is stable.
- Offsite power is available.
- At 8:19am, Mar 12th, there was an alarm indicating that one of the
control rods was not properly inserted, however, at 10:43am, Mar 12th
the alarm was spontaneously called off. Other control rods has been
confirmed that they are fully inserted (reactor is in subcritical status)
- Status of main steam isolation valve: closed
- We do not believe there is leakage of reactor coolant in the
containment vessel at this moment.
- At 5:22am, Mar 12th, the temperature of the suppression chamber
exceeded 100 degrees. As the reactor pressure suppression function was
lost, at 5:22am, Mar 12th, it was determined that a specific incident
stipulated in article 15, clause 1 has occurred.
- We decided to prepare implementing measures to reduce the pressure of
the reactor containment vessel (partial discharge of air containing
radioactive materials) in order to fully secure safety. This preparation
work started at around 9:43am, Mar 12th and finished at 6:30pm, Mar 12th.
- Restoration work in reactor cooling function that was conducted to
achieve reactor cold shutdown has been completed and cooling of the
reactor has been commenced at 1:24 am, Mar 14th.
- At 10:15am, Mar 14th, it has been confirmed that the average water
temperature of the suppression chamber has continuously fell bellow 100
degrees.
- At present, the unit has achieved reactor cold shutdown.

Unit 2 (shut down at 2:48pm on Mar 11th)
- Reactor is shut down and reactor water level is stable.
- Offsite power is available.
- Control rods are fully inserted (reactor is in subcritical status)
- Status of main steam isolation valve: closed
- We do not believe there is leakage of reactor coolant in the
containment vessel.
- At 5:32am, Mar 12th, the temperature of the suppression chamber
exceeded 100 degrees. As the reactor pressure suppression function was
lost, at 5:32am, Mar 12th, it was determined that a specific incident
stipulated in article 15, clause 1 has occurred.
- We decided to prepare implementing measures to reduce the pressure of
the reactor containment vessel (partial discharge of air containing
radioactive materials) in order to fully secure safety. This preparation
work started at around 10:33am, Mar 12th and finished at 10:58pm, Mar
12th.
- Restoration work in reactor cooling function that was conducted to
achieve reactor cold shutdown has been completed and cooling of the
reactor has been commenced at 7:13 am, Mar 14th.
- At 3:52pm, Mar 14th, it has been confirmed that the average water
temperature of the suppression chamber has continuously fell bellow 100
degrees.
- At present, the unit has achieved reactor cold shutdown.

Unit 3 (shut down at 2:48pm on March 11th)
- Reactor is shut down and reactor water level is stable.
- Offsite power is available.
- Control rods are fully inserted (reactor is in subcritical status)
- Status of main steam isolation valve: closed
- We do not believe there is leakage of reactor coolant in the
containment vessel.
- We decided to prepare implementing measures to reduce the pressure of
the reactor containment vessel (partial discharge of air containing
radioactive materials) in order to fully secure safety. The preparation
woke started at around 12:08pm, Mar 12th and finished at 12:13pm, Mar
12th.
- At present, the unit has achieved reactor cold shutdown.

Unit 4 (shut down at 2:48pm on March 11th)
- Reactor is shut down and reactor water level is stable.
- Offsite power is available.
- At 0:43pm, Mar 13th, there was a signal indicating that one of the
control rods may have not properly inserted. However, we confirmed that
it was inserted completely by another signal. We will inspect the reason
of this.
- Status of main steam isolation valve: closed
- We do not believe there is leakage of reactor coolant in the
containment vessel.
- In order to cool down the reactor, injection of water into the reactor
had been done by the Reactor Core Isolation Cooling System, however,
At 6:07am, Mar 12th, the temperature of the suppression chamber exceeded
100 degrees. As the reactor pressure suppression function was lost,
at 6:07am, Mar 12th, it was determined that a specific incident
stipulated in article 15, clause 1 has occurred.
- We decided to prepare implementing measures to reduce the pressure of
the reactor containment vessel (partial discharge of air containing
radioactive materials) in order to fully secure safety. The preparation
woke started at around 11:44am, Mar 12th and finished at around 11:52am,
Mar 12th.
- Restoration work in reactor cooling function that was conducted to
achieve reactor cold shutdown has been completed and cooling of the
reactor has been commenced at 3:42 pm, Mar 14th.
- At 7:15pm, Mar 15th, it has been confirmed that the average water
temperature of the suppression chamber has continuously fell bellow 100
degrees.
- At present, the unit has achieved reactor cold shutdown.
- At approximately 11:01am, Mar 14th, an explosion followed by white
smoke occurred at the reactor building of Unit 3. It was believed to be
a hydrogen explosion.
- There was an increase of radiation dose at site boundary measured at
the monitoring post of Fukushima Daini Nuclear Power Station.
Accordingly, at 10:07pm Mar 14th and at 12:35am Mar 15th, it was
determined that that a specific incident stipulated in article 10,
clause 1 (Increase of radiation dose at site boundary) has occurred.
- We will continue to monitor in detail the possibility of radioactive
material being discharged from exhaust stack or discharge canal.

[divvy]

18. Magnitude of 40 rem/hr

40 rem/hr is a lot. In the Navy, 500 mrem is the maximum annual exposure for crewmen. (1 mrem = millirem = 1/1000 rem.) In fact the average sailor's exposure is around 0-5 mrem/yr. The occupational limit is 5 rem/yr (=5000 mrem/yr), i.e. 10x higher. These levels are considered to cause no harm.

I wish some of the numbers being bandied about were put into perspective. Radiation measuring equipment is very sensitive so of course it will measure the effect of a release, however small. But accidental radiation exposure should be compared to, for instance, a chest X-Ray, or a cat scan, or a trans-Atlantic flight. Or living near a coal mine. Or having a basement near a radon source.

Without such comparisons, many of the headlines are meaningless, bordering on scare tactics.

But 40 rem/hr is not good and clearly needs to be put under control immediately.

There is still far too little information available to understand what has happened, and what could happen. For instance:

1. Was the primary coolant ruptured by the earthquake, resulting in loss of coolant (and eventual uncovering of the fuel rods, melting of cladding and release of fission products and hydrogen into the reactor containment)? Or did the loss of cooling arise from loss of AC power only...in which case the reactor vessel and primary coolant system integrity would still be intact? (The release of radiation would come via the opening of a relief valve.)

2. Where is the seawater being poured? Directly into the reactor coolant system which is intact? Or on top of the core in a damaged, non-intact reactor coolant system?

3. How much fuel melted? Where is it? In the bottom of the reactor vessel, or still within the fuel assemblies/clusters? If the former (which would be very bad), has boron-10 been effectively inserted to prevent a criticalioty accident (which would, again, be very bad)?

4. Have the steel and reinforced concrete containment domes been breached? Or have the radiation releases occurred because of relief valve discharges?

These all seem to me to be pertinent questions to an understanding of what's happened, and what could happen next. It seems to me that nothing like Chernobyl has happened. Chernobyl was a supercriticality accident: a bad reactor design caused a supercriticality (runaway chain reaction) to occur. While it only lasted a millisecond, the power spiked to thousands of times normal rated power and destroyed the entire core, pressure vessel and building, spraying fuel and fission products for miles around. In Japan, the reactors were shut down (as far as one can tell) instantly via a control rod scram, and they remain shut down (subcritical). The problem, simply, is decay heat.

That decay heat must be removed. Heat moves between two temperatures (a simple equation known as Fourier's Law): . If no heat is being removed, and the outside temperature remains the same (i.e. inside the reactor), then the inside temperature is going to rise, and keep rising, until heat starts to move. That's what causes the zirconium fuel cladding to melt. (The fuel itself is a ceramic - uranium dioxide - and will also melt eventually, but at a much higher temperatrure.)

If the fuel ends up on the bottom of the pressure vessel, that's bad, because there will probably be a slug of uranium mixed with molten zirconium weighing several thousand kg, and if the decay heat cannot be removed, the temperature will simply rise until it burns its way through the pressure vessel (must be about 12" thick or more), and then it will just keep tunnelling its way down until it hits the ground. And that's not good, because fission products will contaminate the ground water, and gaseous fission products will contaminate the air.

So what we really need to understand is: how is the core being cooled?

[divvy]

19. Poisioning

I can't see why plutonium in the fuel would necessarily be any worse than Uranium... most of the air release is the products of the nuclear decay, like iodine, Cesium, strontium, etc. If the actual fuel is spread, then it is a catastrophe either way. If the worst case outcome is the core melts down to the water table, then plutonium is more poisonous than Uranium. Both fuels would be catastrophic. I don't think poisoning is the greatest threat here

edit

There is Plutonium (Pu-239) even in a normal U-235 fueled reactor. Remember the fuel is only 3-4% enriched; the majority is U-238. It undergoes a straightforward reaction: U-238 (n,p) Pu-239. (That's how a breeder works.)

[pokerfan]

76. It's marginally worse

According to Ed Lyman (Union of Concerned Scientists):

One particular concern with Unit 3 is the presence of mixed-oxide (MOX) fuel in the core. MOX is a mixture of plutonium and uranium oxides. In September 2010, 32 fuel assemblies containing MOX fuel were loaded into this reactor. This is about 6% of the core.

I have done considerable analysis on the safety risks associated with using MOX fuel in light-water reactors. The use of MOX generally increases the consequences of severe accidents in which large amounts of radioactive gas and aerosol are released compared to the same accident in a reactor using non-MOX fuel, because MOX fuel contains greater amounts of plutonium and other actinides, such as americium and curium, which have high radio-toxicities.

Because of this, the number of latent cancer fatalities resulting from an accident could increase by as much as a factor of five for a full core of MOX fuel compared to the same accident with no MOX. Fortunately, as noted above, the fraction of the fuel in this reactor that is MOX is small. Even so, I would estimate this could cause a roughly 10% increase in latent cancer fatalities if there were a severe accident with core melt and containment breach, which has not happened at this point and hopefully will not.

http://allthingsnuclear.org/tagged/Japan+nuclear/page/2

[divvy]

20. Breaking ... no details

Reuters news flash, no details:

"Breaking News: Tokyo Electric says may drop water by helicopter onto Daiichi No.4 spent-fuel cooling pond"

http://www.trust.org/alertnet/news/helicopters-may-pour-water-on-japans-crippled-no-4-reactor

[divvy]

21. fissile U-235

in a nutshell, when fissile U-235 breaks into two pieces and releases energy, the two pieces are unstable - they have too many neutrons for their new size. So the neutrons decay, emitting beta and gamma rays.

The fission products are normally isolated from the environment by three barriers: the zirconium cladding around the fuel elements (which are uranium oxide pellets), then the reactor vessel itself, then the steel and reinforced concrete containment structure.

If water cooling inside the reactor is lost, the reactor will be shut down instantly by inserting the control rods, which shut down the chain reaction. The fission of fuel ceases instantly. The problem, however, is this: the existing fission products contained in the fuel continue to release a substantial amount of heat, and with no heat transfer medium to carry that heat away, the zirconium cladding will melt, releasing the uranium dioxide fuel pellets and the fission products (which are both solid and gaseous) into the reactor coolant system. If the reactor coolant system has been breached, then these products will be released into the reactor building itself.

[divvy]

22. Update

When they said they were injecting seawater (apparently with diesel driven fire pumps), I thought they had de-pressurized the reactor vessel, filled it, and filling the torus and containment with seawater. Apparently, that is not the case. They still have the reactor at high pressure and are using seawater in the feed water system to maintain water level. Apparently, HPCI is no longer available... Probably due to inability to cool the torus water. This is a tenuous configuration as the recent core uncovery makes obvious. None of the Main Control Room instrumentation probably works (all of it is A/C powered). The only way to read water level is at an instrument rack outside the drywell in that blown up reactor building. In fact, there were very likely operators standing at those racks when the building walls blew out. The same for reactor pressure... they are reading a gauge at an instrument rack. Feed water level is usually automatic, so that air pressure regulator you hear them talking about is a "Jerry rigged" air line the operators have to open the feed water regulating valve "manually." They need to fool that valve into opening or disconnecting the ordinary air supply and provide a manually generated "signal" to open. They could do that with a portable air compressor and air regulator, because there is probably no instrument air in the plant (no AC). With no power and no AC, most valves have to be manually manipulated, if that is possible. This may be boring... Just trying to convey to you what the operators are fighting against. At night, there are no lights other than portable units that might have been brought in. It is cold at night... They have no beds... They are worried about what might have happened to their loved ones, but they can't leave to find out. Probably no phones... Their radio system is probably not working, but they may be able to talk radio-to-radio on batteries. There have been multiple explosions where they are working

[divvy]

23. Good response list

Here are things that a good response to the crisis would have. I am not saying it is or isn't happening. I don't know. 1) there should be 6 response teams, not one team for 6 plants... 2) there should be an army of engineers brainstorming to support the operators onsite... 3) the teams should have a plan and timeline for restoring each plant to a safe shutdown condition... 4) the plant designers such as GE and/or Toshiba should have been asked or paid to form an emergency response team and provide advice... 5) each system at the plant should be reviewed to determine whether or not it is needed to safely operate the plant to safe shutdown (the fuel pool fire problem should have been anticipated and prevented) and a plan in place to restore it, if necessary.... 6) work crews from these and unstricken plants should be cycled through this site to prevent lethal exposures... 7) this site will not be normal until AC power is restored... There should be bulldozers and whatever is needed working on just that! Airlift generators... Put up a transmission line... Whatever... More power! I wish I could see more of these things being done. Maybe it is, but I am not hearing them talk about it. I am also not seeing the response to an uncovered core that I was trained to do. I don't know if what they are doing is better, or not. Maybe here is a good reason for he discrepancy. It wasn't what I was taught and that concerns me... If they can keep the core covered, fine... but if not, I don't know. These hydrogen explosions are a bad sign that the fuel is in bad shape now. Each explosion is a risk of damage to remaining safety equipment and barriers. Just some random thoughts... 40 Rem/hr? If memory serves me, 300 Rem is potentially lethal. 200 Rem and you may have radiation sickness.

[divvy]

24. Potassium Iodine

A few thoughts about potassium iodine pills... Don't use it if you are over 40 or have a shell fish allergy. Many claim that it is nearly worthless, but it was moderately effective after the Chernobyl event. You should take it before exposure to radioactive iodine, not during it. It isn't helpful against any other kind of radiation exposure. XXXX The most danger from an ongoing radiological release is down wind... Be you an aircraft pilot, ship, or Tokyo. If you can, don't be down wind of the plant. Evacuation zones in US evacuation plans are always further down wind. If you can't evacuate, shelter... The people in Japan should be told what to do... And I assume they are. I wouldn't drink any milk in Japan... Especially children. Radioactive fallout goes through cows and to the milk incredibly quickly. Wash fresh vegetables very thoroughly

[divvy]

120. food

I would hope that we stop accepting food from Japan (soon). I don't know if we have the capability to inspect all of it. If we can check it,, fine... check it and let it in. Europe was a lot closer to Chernobyl than the US is to Japan. It is a benefit to have an ocean between us and the accident, instead of ground where contamination can be spread more easily. I don't think there is a big danger, but eat canned food if you want. It would have been canned "in season" a long time ago.

12. Chernobyl's radioactive contamination of food and people.

Nesterenko AV, Nesterenko VB, Yablokov AV.

Institute of Radiation Safety (BELRAD), 2-nd Marusinsky St. 27, Minsk 220053, Belarus. [e-mail]

Abstract
In many European countries levels of I-131, Cs-134/137, Sr-90, and other radionuclides in milk, dairy products, vegetables, grains, meat, and fish increased drastically (sometimes as much as 1,000-fold) immediately after the catastrophe.

http://www.ncbi.nlm.nih.gov/pubmed/20002056

[divvy]

25. Radiation Trajectory

Dr Jeff Masters has a thoughtful analysis of the forward radiation trajectory here

http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=1763

[divvy]

26. Mox

A quick google suggests the Fukushima I (Daiichi) units are...

Unit 1: BWR-3/Mark I, LEU
Unit 2: BWR-4/Mark I, LEU
Unit 3: BWR-4/Mark I, MOX (since 09/2010 supposedly)
Unit 4: BWR-4/Mark I, LEU
Unit 5: BWR-4/Mark I, LEU
Unit 6: BWR-5/Mark II, LEU

I think either Uranium or Plutonium in water table is extremely unlikely. Remember that MOX is mixed oxide - and most oxides are insoluble in water. So the danger is not likely to be that water table would be poisoned. It is likely from the radiation laden vapor releases.

A bit of basic chemistry that I vaguely remember: Even if MOX melts, and goes thru the RX bottom into water, it is unlikely to change to a water soluble form - (say a chloride). Generally speaking, the oxides are more stable at most temperatures (including high temperatures) than most chlorides, so a metal in the form of molten oxide is unlikely to change to a chloride form. The bigger danger is likely to result from the radioactive iodine, Cs & Sr molecules in vapors.

[divvy]

27. Things seem to be deteriorating

Things are deteriorating badly. Just as I feared, if one Unit goes to hello, the site dose rates will make it difficult to keep personnel onsite working on any of the Units. Dose rates have been reported of about 350 mR/hr. 5000 is the normal annual limit. At work, I don't think we ever allowed more than 1000mR in a day. If the dose gets worse, well forget it... The only reason for staying is if you have a plan that can succeed. They still haven't done what I thought was the final strategy. Let the core uncover, drain the vessel, and flood the containment. That is what I was taught to do if you couldn't keep the core fully covered... for whatever reason. The core will melt down, but that is unavoidable if you can't keep it covered. It seems counter-productive to intentionally empty the vessel, but that is what they taught us. It is the only way to pressurize the vessel without low pressure injection systems. By the way, those shutdown plants may not be safe... They don't have core cooling and their operators may have to leave the site, too. 6 plants are in danger, not 3... Unless there is info I haven't heard

When they said they were injecting seawater (apparently with diesel driven fire pumps), I thought they had de-pressurized the reactor vessel, filled it, and filling the torus and containment with seawater. Apparently, that is not the case. They still have the reactor at high pressure and are using seawater in the feed water system to maintain water level. Apparently, HPCI is no longer available... Probably due to inability to cool the torus water. This is a tenuous configuration as the recent core uncovery makes obvious. None of the Main Control Room instrumentation probably works (all of it is A/C powered). The only way to read water level is at an instrument rack outside the drywell in that blown up reactor building. In fact, there were very likely operators standing at those racks when the building walls blew out. The same for reactor pressure... they are reading a gauge at an instrument rack. Feed water level is usually automatic, so that air pressure regulator you hear them talking about is a "Jerry rigged" air line the operators have to open the feed water regulating valve "manually." They need to fool that valve into opening or disconnecting the ordinary air supply and provide a manually generated "signal" to open. They could do that with a portable air compressor and air regulator, because there is probably no instrument air in the plant (no AC). With no power and no AC, most valves have to be manually manipulated, if that is possible. This may be boring... Just trying to convey to you what the operators are fighting against. At night, there are no lights other than portable units that might have been brought in. It is cold at night... They have no beds... They are worried about what might have happened to their loved ones, but they can't leave to find out. Probably no phones... Their radio system is probably not working, but they may be able to talk radio-to-radio on batteries. There have been multiple explosions where they are working

[Prometheus Bound]

30. You are certainy a wealth of solid information.

Thank you.

[divvy]

31. Conflicting U4 stories

We are getting conflicting stories about what is happening in U4 and its spent fuel pool. I don't think a lubricating oil fire is likely. The water chemistry requirements in a nuclear plant don't allow large quantities of lubricating fluid laying around. There is not much that is normally flammable on a refuel floor. Why did radiation spike up? This doesn't sound true. Normally, there are design limits placed on the location of fuel bundles in fuel pool racks that would prevent fuel bundles from getting so hot as to allow zirc hydrating and hydrogen generation. This may not be the case if there was hot fuel "temporarily" removed from the reactor vessel during the refueling operation. It would only take one bundle to cause a ig problem. It may also not be true at current water temperatures. As I listen to CNN, it sounds like the fire has re-ignited on the refuel floor. Long before a spent fuel pool uncovered (there is normally 30 feet or so of water over this fuel), dose rates would soar. If water level dropped even a foot would raise normal dose rates from 5-10 mR to 100 mR. They should be able to adequately cool these pools (1 for each Unit) by running a fire hose (or 2) into each pool. Use common ordinary fire truck tankers with well water. Drop the hoses into the bottom of the pool and let it overflow. It will contaminate the heck out of the place, but you will get a flow to take away the heat. If they don't get this under control, they will have to abandon the site as radiation levels would become lethal. There are 6 fuel pools in danger! Even one spent fuel pool failure makes this a Chernobyl or worse. Six? If the site is abandoned, all 6 will probably boil or evaporate dry eventually. Can it explode like Chernobyl? Maybe! The design basis for our fuel pool was 140 degF. When you go way beyond that, I don't know... Maybe! I don't mean to scare anyone, but this story line is getting worse every day. Plans should start for evacuating non-essential Americans from Japan. It may not be necessary, but it is a huge job

[divvy]

32. explosions are not good

Reports of explosions are not good... No kidding. The zircolloy reaction of clad melting gives off a lot of hydrogen, which can accumulate in the top of the reactor vessel. Such a bubble of explosive gasses is very dangerous. Large scale fuel failure is probably happening at multiple plants. My guess is that the explosions are from hydrogen vented from the vessel. That is a sign of fuel clad "melting." Core melting doesn't necessarily mean that the worst case scenario will result... It didn't at TMI. As long as they can prevent reactor vessel failure, the impact on the general public can be minimized. Reports of loss of life by operators at the plant are sad. They are casualties in a battle to save lives... Heroes! They were doing their job until the end... I know the GE Mark I plant had design provisions for pumping seawater into the reactor... I don't know if the other plant designs did. I haven't heard what resources are being brought in to help plant personnel. They need help... Not just advice! What is being done to restore power to these stricken plants? ... And when will they have it? No plant, even one originally in cold shutdown, can operate indefinitely without AC power. I guess I am frustrated to hear of casualties... People can't go into primary containment under these circumstances. Venting should be to primary containment, which could then be vented through a standby gas treatment system in the RX building, if there is AC power to run it. That could be where the hydrogen explosion occurred. The system has a heater that wouldn't be good with an explosive mix of hydrogen. PWRs actually have glow plugs or some type of heaters to burn hydrogen inside their much larger containments. BWRs don't have these systems. The Mark I containment could not accommodate open flames... too small.

[divvy]

33. Fuel casks are different than the spent fuel pool

Any fuel in those 100 ton casks is safe. If they had one of those casks suspended over the ful pool from a crane when the earth quake hit, not good! I don't think all the fuel could be in casks, though. The spent fuel is let cool off for years in the pool, before putting he fuel into a cask. What to do with spent fuel has obvIously been a controversial topic, but the risks associated with he current configurations is near and dear to my heart. If HPCI worked at those 3 plants, fuel failure could have been prevented. The hydrogen explosion at the first plant is a sign that it didn't work there. I would say that the odds of some fuel failure after a design basis + earth quake, tsunami, loss of all offsite power, and loss of all emergency generators was likely... A core meltdown was not certain but probably likely to the tune of 33 or 50%.

This event has passed TMI in severity (I would estimate the financial loss at 10-15 billion dollars, including fuel. The cost to cleanup the mess will be at least a billion. Those numbers assume that we have seen the worst of the outcomes. The goal is to prevent a Chernobyl, where there was large scale loss of life and a large "permanent" exclusion zone. That is still possible.

[divvy]

34. SELF-DELETED BY MEMBER

This message was self-deleted by divvy.

[divvy]

37. fuel pool notes

1) The spent fuel pools for Mark I containments are above the core, because the cores are top loaded and it makes fuel transport under water easier. Our control rods come in from the bottom. PWRs are the other way around, I know. Most of the heavy design work went into making sure that the pools couldn't be accdentally drained. There are no drains... the pool has leak detection equipment... all kinds of level, radiation, anti-syphon configurations, and temperature alarms... piping connections are all high in the pool. The easy way to get water up there was a fire hydrant right next to the pool (our fire pumps were redundant diesels) and if the fire system was down, a fire hose could be run up the stairwell. All you need is a tanker fire truck. Why, in 4 days, it never occurred to the utility to do it until dose was so high they can't do it, I don't know. 2) The last news I received is that they pulled everybody from the site.. those out of control fuel pools must have near lethal doses now. There is stuff they could have done in preparation of abandoning the reactor cores, but they don't seem to have done it (eg, flooding containment and draining he vessel). I can imagine a meltdown... I can't even imagine what those fuel pools will end up doing. We are way beyond TMI. I said from the very beginning that there were 6, not 3, plants in big trouble. The only thing that would have terminated this event was restoring AC power to site equipment. I never heard a single report on the status of doing that. The worst case has happened. There can be no good outcome now. I would be asking somebody if they can "shoot" a fire nozzle into the pool. There may not be that much they can do about the reactor cores, but they had better think about what they are going to do about those spent fuel pools unless they don't mind evacuating Japan. This is the worst possible outcome that I can imagine.

[divvy]

41. Chernobyl statement clarification

My statement that each pool could be a Chernobyl was based on nothing successful being accomplished to refill the pools and establish some cooling. That seemed to be the likely outcome when all workers left the site. I am glad to hear that radiation leves dropped and they returned. The stuation will keep getting worse if they are't successful pretty soon. If they don't stabilize the fuel pools, pretty soon they won't be able to stay onsite. Maybe I am wrong... I hope so.

[divvy]

44. re-post

**I linked copyrighted material. this is a repost of the deleted comment**

Let me say this, at this point the site operators had a choice... stay and die or leave. That's all... There may not be any choice but to walk away from the 3 melting down cores. I don't know what the status of the other 3 Units' cores... if they are in the vessels (most likely), they will melt down, too. Those fuel pools, though... you can't walk away from them. Virtually all the Secondary Containments are breached or completely destroyed. The bad effects from these pools are just beginning. Before they are done, each will be nastier than Chernobyl. Walking away, OK, but the fight is only beginning.

[divvy]

35. Iodine on the bay area news

http://www.nbcbayarea.com/news/local/Surgeon-General-Buying-Iodine-Appropriate-118031559.html

Apparently, China has started evacuating their citizens from northern Japan. If you are in the US and are contemplating taking Potassium Iodine... I agree with NBC that the best thing you could do with them is donating them to Japan. Don't take them... there are a fair number of medical complications that could arise. We are not at risk here on the other side of the world... if you don't believe that, distance gives you time. I don't understand the Surgeon General's warning. I don't think that is the right person to make such an announcement. I don't know about irresponsible... I remember being told after 9/11 to duct tape and seal a room in the house in case of a gas attack. Now that was silly and cared a lot of people. It is interesting to see journalists in this country cover the accident. Considering that they are not engineers and probably went into this accident not knowing much about a nuclear plant, I think CNN and NBC have done a pretty good job. Sure, occasionally I was shown a picture of a PWR instead of a BWR... but for the most part, I think they did a good job. I will wait until this accident is over, before I comment on the utility's response. About the Japanese people, they are very impressive. I can't imagine losing so much and exhibiting more class. The Japanese people are very impressive.

[divvy]

36. SELF-DELETED BY MEMBER

This message was self-deleted by divvy.

[divvy]

57. copyright

I deleted this message because it contained copyrighted material.

The comments that follow were first posted 3/12. Let's review where we came from.

[divvy]

58. 3-12-11 #1

It very well could be the worst nuclear disaster ever. I would like to say that it is my experience (25 years in nuclear power and a trained member of an emergency response team at a nuclear plant) that it would be impossible to prevent the fuel failure of a plant after a design basis earthquake and a tsunami loss of all offside power and all of the emergency generators, if that is what has happened. There is not likely enough batteries to last more than 4-8 hours... and little pumping capacity even then. This would be the first time that multiple reactors (3) would be lost at one site. Both TMI and Chernobyl only involved the loss of 1 unit at a site. The big unknown in my mind is what is the status of the spent fuel pools. I haven't heard whether these are PWRs or BWRs... That would say a lot about he spent fuel pool configuration. If the spent fuel pools are not cooled and an adequate water coverage maintained, the danger is off the map. There is more time to get that accomplished, but the ramifications of failure are beyond my imagination to describe. A prayer couldn't hurt. I didn't know until late last night that they had no emergency generators. Not good... I don't know how many plants are designed for 8.9 and Tsumami. Japan may have designed more into their systems for it... my plant was thousands of miles from the ocean. I hope so... but they are in the battle of their lives... I can tell you that. The Japanese engineers are good... A prayer wouldn't hurt.

[divvy]

59. 3-12-11 #2 affected reactors

what are the effected reactors? There are new designs that are far safer than the US plants I am familiar with. I assumed it wasn't a BWR, what I am most familiar with, when the reactor building collapsed and radiation wasn't off the charts. The spent fuel pool is in the top of our reactor building. There are blowout panels to prevent an explosion from destroying the reactor building. I worked at a plant designed in the 60's. I think you are nuclear navy, so you probably know more about PWR's than I do. I agree that it is too early to know how much damage will be done. The first goal is to prevent core damage... some damage, like TMI, is a financial disaster, but not a human catastrophe, like Chernobyl. The expanded evacuation zone and the reports of Cesium in the air means that some Coolant release is happening, probably intentional to control RX pressure. The hydrogen explosion that has destroyed one containment building could very well be from "melting" fuel cladding, but I can't say that for certain. No offsite power... No emergency generators... No containment... Expanding evacuation zone... I'm worried! I understand politicians saying things to avoid panic, but there is plenty to worry about. Because of the time that has elapsed since the units SCRAM'd, it looks like they have managed to keep the reactor cores cooled and pressure under control, but they lack the ability to take the reactor(s) to shutdown. Low pressure injection has probably been lost. They need electrical power! Bad! Not easy in an earthquake damaged country. One unconfirmed report that they were injecting sea water into the containment means that normal emergency systems have failed and the situation is pretty desperate. The other 2 plants? Fuel pools? The fuel pools are probably OK, because they could keep them full with a fire truck tanker... As long as radiation levels onsite stay reasonably low. I don't think any plants, but the most recent designs, would do well after control rooms become uninhabitable. The collapsed reactor building probably eliminated most, if not all, remaining capabilities of that stricken reactor. If it was a sub, you would get out and sink it. Not good... Pumping sea water in the containment is the equivalent. I hope that report is false. I don't mean to frighten anyone, but this is very serious and could get a lot worse. Obviously, the news may not have all the info one would need to have to now how serious this will become, but it is bad now!

[divvy]

60. 3-12-11 #3 SCRAM'd

"Shutdown" is a misnomer. They SCRAM'd, inserting control rods and ceased electrical generation. They couldn't have reached cold shutdown in an hour... If radiation levels are really declining, then they are probably keeping the reactor cores covered. That is obviously a good thing, but I doubt they have enough equipment running to get the Units in cold shutdown, especially at the plant with a collapsed reactor building. BWR's have 2 containments - primary and secondary... it looked like a secondary containment going down (a building). There is still a concrete or steel primary containment around the reactor vessel... I think. They must have a different fuel storage system than the one I am used to. Like I said, the Japanese engineers are good... It is good that the plant is in a country so technologically advanced. I am sure they have experts worldwide on "speed dial." Reports say 4 were hurt when the reactor building collapsed. Other reports say that some of the plant workers "walked" into a Tsunami when they initially evacuated non-essential personnel. That may have also taken out the emergency generators. It would explain the loss of all 14 of them. These operators are facing great challenges without much rest. They are well trained and I am sure they are doing everything they can... I pray it is enough. Loss of offsite power and all emergency generators is a typical training scenario, but it isn't usually one that any nuclear professional would want to see. Fuel damage and evacuation is likely. Times 3, not good! I am not sure what is keeping the 2 reactors in better shape than the 3rd, but they are all in grave danger if they cannot restore AC power or site radiation levels rise greatly due to the 1 reactor in more desperate condition.

[divvy]

38. Japan may seek U.S. military help

Japan says may seek direct U.S. military help to cool reactors

(Reuters) - Japan may seek direct U.S. military help to end a crisis at a quake-damaged nuclear power plant in northeastern Japan, the chief government spokesman said on Wednesday.

That is the entire release!

[divvy]

39. Ground level and satellite imagery

Ground level photo Reactor 3 (near) & 4 (far)



Perhaps someone else noticed, but in the Digital Globe (commercial satellite imagery company) photo after the Reactor 3 explosion Reactor 4 appears intact:



This and some other Digital Globe images are higher resolution do check them out and zoom in.

[divvy]

40. fuel pool

When I was a young, rookie engineer, a mentor told me about the hidden terror in the fuel pool. He said to me that if a crane operator latched onto a fuel bundle and hit the UP button (there are interlocks to prevent that), by the time the top of the bundle reached the surface, everyone on the refuel floor would be dead... nobody would make it off the floor. There are hundreds of bundles in the pool. I don't know if this story is true, but I never had any reason to doubt it. Hydrogen burning will accellerate the loss of water in the pool. The pool liner and structure can't handle fuel meltdowns. Once the 1/4" or so stainless steel liner is breached, the pool will never hold water again. Hydrogen explosions could be devastating in spreading radioactove material, a hazard worse than just radiation "shine." It may look a lot like explosions to the lay person. I would rather see a core meltdown than an empty fuel pool. I think we are looking at something similar to Chernobyl. Hopefully, less devastating in loss of life... but something that may be even harder to control. I am not sure how long we have to turn this around... maybe a couple days... maybe not. I'm not smart enough to caculate the answer, but there are people that are. Chang, the amount of radioactive materials in these pools is many multiples of what was in Chernobyl. As the water level lowers, you are going to have steam "explosions", hydrogen burning and explosions... there are calculations to calculate Keff for each bundle to insure that no bundle can go critical, even in localized areas... how good do you think those calculations are now, Chang. I don't know how bad it will be, but I am not so certain that it won't be aweful. Will the whole pool meltdown? No, but it doesn't have to to still be very bad. Once the pool is filled and cooled, the water needs to be cleaned up. It is probable very acidic right now... very corrosive.

[divvy]

42. SL-1

Did you ever watch the film the Army made after the SL-1 accident in the early 1960s? I did while I was in the Navy. Briefly, for those who don't know, SL-1 was a small, 3MW Army (not Navy!) reactor. It was somewhere in the middle of nowhere in Idaho, I think. There were three workmen in the reactor building at the time of the accident. Two were standing on the pressure vessel head. You're not going to believe this, but the central control rod was being lifted up by hand to connect it somehow to its control drive mechanism. The technician withdrew it too far and caused a prompt criticality. Reactor power spiked to 20,000MW for a fraction of a second. The power spike vaporized the water in the system and caused a steam explosion, which ejected all the control rods and drive mechanisms (one impaled a technician on the ceiling). The photo below shows a control drive mechanism stuck in the ceiling. All three workers died, and a small amount of radioactive contamination of the surrounding area took place.

It's simply unbelievable what people did in the 1960s. Anyway, criticality accidents are very bad. Japan had one a few years ago at an enrichment or fuel processing plant, it killed one or two workers. I'm actually surprised at some of the lapses which seem to take place in Japan. I associate the Japanese with the same level of rigorous, strict adherence to proper procedures as the Swiss.

I did see the film of SL-1. I think that you may be right. It depends a lot on how you define what is "badness." The cost of this accident has already surpassed Chernobyl... with 6 Units being destroyed. This accident will probably not have as many lives lost... hopefully none. Chernobyl killed about 80 people, I think. Chernobyl spread radioactive material over 2 continents... that shouldn't be the case here. It is good that the prevailing winds is into the pacofic. I understand your thinking about the explosive nature of the Chernobyl event. The Japanese Units are in a much more densely populated area, though. It potentially affects a lot more people. There are about 200,000 people evacuated now... and I would expect the danger to increase from here. Conditions are a lot better now than after the cores melt down, assuming that they do. Conditions are a lot better now than after the fuel pools uncover. I wonder what will make anything any better for hundreds of years. Will those 200,000 go home or will it become a million? I don't know, but I see this event dislocating a lot more people than Chernobyl did. There is a lot more radioactive material in those pools. When the fuel rods over-heat, they will break open and release a lot of vaporized fission products. Fuel bundles are very carefully positioned in fuel pools to prevent any possible criticality. In the pool, there are no control rods keeping the fuel shutdown. Some high density racks have boron, but for the most part it is the very careful positioning in he pool that prevents criticality. A bundle mis-position event, even temporary is a very serious event at a nuclear plant. Now? You have a mess that is getting messier. Secondary containment is gone. If you had bundles going critical, even in reatively small areas of the bundle, I don't know. That has never happened before as far as I know. Barb, I became aware of Tepco's poor record last night. I have also started to hear TV experts question how good a job Tepco has done during this catastrophe. The things that bother me the most - 1) the fuel pool is pretty inexcusable... didn't they have any operators making rounds in the 3 plants that weren't in immediate meltdown danger? They should have observed high pool temps, increasing radiation levels, etc. This part of the crisis was predictable and avoidable 2) what have they done to restore AC power? None of these plants can be put into safe shutdown without AC power. Can't use sea water forever. 3) Letting a diesel run out of fuel when core coverage depends on it, alone... dahhhh, I think there was also a mistake that closed a valve preventing "feedwater" flow 4) It seems to me like they were slow to ask for help... seems a little like covering you @$$ after you have messed up... I think that the nuclear community would have eagerly helped

[divvy]

43. Refueling

A BWR has a massive steam separator and dryer in the top of the vessel. You remove them to refuel. It would be impssible to run control rods through them. Once you are locked into bottom entering control rods, you pretty much have to refuel from above. Obviously, PWRs don't need steam separators or dryers. BWRs and PWRs both have advantages and disadvantages. I never could understand making water that hot, either. PWRs also don't have as much core instrumentation (eg level instumentation, because they are suppsed to be full, except at TMI they weren't)... the nuclear world has more PWR's, but I do not think they necessarily have a safety advantage. They do have better containments. I have said before... I don't think I would rely too much on these primary containments for leak tightness. The containment isolation valves may not even be closed. Most are AC... The Mark I containment is near and dear to my heart, too. I did containment testing for years, both valves and the structure. Most of the later designed BWRs had containments more like PWRs in that they were a lot larger and made of reinforced concrete. The Mark I is a painted carbon steel primary containment that is various thicknesses, but typically 5/8". It was designed to hold about 60 psig. It does have a few feet of concrete poured into the bottom of it. Molten fuel, after exiting the vessel, would go through carbon steel like butter, I'm afraid. The concrete... not so fast... then there is the building foundation... a lot more concrete... but this is outside the containment. Many people mistake the Mark I for a concrete containment, because it has concrete shielding walls around it, but these walls are not solid... many openings and don't extend to the lower parts of the drywell. Sorry if none of that makes you feel better. I hope the melted rods stay in the core region. There is a lot of stuff that comes through the bottom of the vessel... it isn't just a 6" thick piece of SS. I don't know the weakest link.

[divvy]

45. helicopter effort abandoned

"The helicopter effort had to be abandoned because radiation doses directly above the No 3 reactor were found to be above the 50 millisievert limit for military pilots."



I assume that's 50 millisievert per hour (they should report more accurately). 1 Sv = 100 rem (these are units of energy absorption modified to reflect biological damage, by assigning differents weights to the different radiation types). 50 mSv = 5 rem, which is the maximum dose that an occupational worker should receive in one year. Assuming it takes less than one hour in the required aerial position, I don't understand why they had to abandon.

This is just another of many examples of incomplete information. That is why I am making no firm guesses yet. Everything I read and hear has giant gaps in it.

I share the concern about the fuel storage pools. These don't have any of the cointainment barriers that apply to fuel in the reactor vessel (which is mixed with steel from the various reactor internals, core barrel, reflectors, support plates etc. plus the control rods).

[divvy]

46. basic radiation calculations

rem and 1/1000 rem = mrem are still the a basic units of biological damage.* 1 Sievert = 100 rem (that's a lot ... 1000 rem is usually fatal in 24 hours). Or if you prefer, 1 millisievert = 100 mrem.

You probably remember that a crewman's maximum annual exposure is 500 mrem, which is 1/10 of the maximum annual occupational exposure of 5 rem. (In actuality, I never knew a sailor who got more than 1-2 mrem during a three-month patrol .... less than you'd get on the surface).

* You get rem by taking rads, which measure energy absorption (1 rad = 100 ergs of energy absorbed by 1 gram of tissue) and multiplying by a "quality factor" which depends upon the radiation in question (alpha, beta, gamma rays).

[divvy]

47. more on spent fuel pools

I think my real point, that I wasn't making very well, about the sent fuel pools is that the situation is too serious to walk away from. That isn't an option... they have to get water into that pool and keep it there or the situation will get much worse, as if it isn't bad enough already. The pool will not hold molten fuel for long. A dry spent fuel pool will have fuel rods breaking open with no containment. The barriers are now just the cladding... then there would be none. I can't say for certain there will be no explosion. You are closer to a nuclear engineer than I am... what I know about the neclear reactions is pretty much just what operator's are taught. Will all those rods and bundles stay sub critical? Without water, they wouldn't have moderation... but I am not sure about having water and losing configuration control due to all that has happened to those bundles... and the elevated temperatures. If there is a nuclear reaction in the pool, what would that mean in terms of dose and the spread of contamination? If you fail the fuel pool liner, I don't know what the end game would look like. Dose rates would be "permanently" too high to ever remove the fuel. You would have to erect some shielding around 6 pools. The technology doesn't exist today. The really scary part of the situation is that it is getting worse as time goes on... not very much done so far has changed the ultimate outcome. It has been like swimming upstream against a strong current. Better strategies are needed... somebody needs to be looking at the big picture and determining everything that needs to be done to safely stabilize those plants... just walking away will never be an option. I don't know if we know how bad it will get. What will be the permanent exclusion zone? The Dept of Energy has people that can probably figure that out. As I said early in this tread, I can't imagine how bad it would be. I can imagine Chernobyl, because I have seen it. I can't imagine what those fuel pools will be like if we let them go dry or the liner bottom is lost. The unknown may not be as bad as Chernobyl. I hope not, but I don't know... this is the worst scenario I could ever imgine while working a nuke plant for 25 years. I never dreamed that it would happen x6. If we just walked away now, all 6 plants would eventually have melted cores and fuel pools. The only difference in any of these plants is the time line for the failures. You can't stay in cold shutdown with no AC power. These plants cannot be controlled with no operators present. You can't cool the fuel pool with no power or alternative intervention. You could scuttle a sub, but that unfortunately isn't an option here.

[divvy]

48. spent rod storage

I undertand the advantage of gravity assisted control rods. There is no way to have an efficient steam drum with a bunch of holes in it... BWRs mke steam in the reactor. Why isn't everything in casks? ... because of the confusion over the ultimate storage location of fuel... spent fuel was supposed to be the government's problem. That was the law when these plants were built. I think you would still have to have a couple reloads in the pool before casks can hold them. You have to let them cool off. U4 deteriorated the fastest, because it had the most recently removed fuel. The heat load on a fuel pool cooling sstem doubles during refueling and immediately after removing "fresh" spent fuel. There is a big difference in heat coming from a 10 or 20 year old spent fuel bundle and one that came out 3 mos ago. The old bundles are put in casks.

out on a limb here ..

why not drive a sub right into the plant's loading jetty and hook up a cable? When we pulled into port we could hook up to shore power in much less than an hour and shut down the reactor. Except run it in reverse - let the sub provide the power. You just need 1 nuclear submarine + 1 power cable. I'm sure somebody has thought of this.

[divvy]

49. Dr Chu's testimony

I just saw Dr. Chu's testimony yesterday. He didn't give the all clear for US. The short story is rhat he situation is fluid and hey are assessing and monitoring the situation. Perhaps I was the one irresponsible saying we are safe here on the other side of the world. It is true that we don't know how bad this would get. I do believe that the US should consider how to evacuate US citizens in large numbers from Japan. it may be premature to start he evacuation, but it isn't too early to figure out how to do it... cruise liners? troop carriers? navy ships? air? Assembly areas? I don't know how many Americans are in Japan, but I am pretty certain it is a lot!

[divvy]

50. New power line

A new power line? That is very good news... but it won't end the crisis. You have to decide where to connect to. For each plant, you have to be able to work there (dose)... you have to be able to assess what still works if powered up (what lines are broken... what switchgear is undamaged... what electrical cables aren't damaged). It is good news, but it isn't even close to being as simple as plugging into a " cigarette lighter" or a golf cart charger. The RX building of at least 2 Units are destroyed. That is where most of the safety related switchgear is. It is going to require running temporary cables all over the plant. My guess is that normal condensate/feedwater might be easier to restore than RHR/LPCI, but maybe not... those pumps are in water tight compartments in he RX building basement around the torus and their piping is seismicly qualified. Hard to say what the dose rates are... I imagine it will be hard to get there... the elevator doesn't work. You would also want to crank up fuel pool cooling if you can. This will cause screaming doses in the area of the RX building. That system is pretty high rad anyway... Hard to say what hasn't been damaged in some of those plants. You need high voltage (eg 4kv, 3ph) for pump power... you need control power if you want to be able to start and stop them. Some instrument power would be nice, but you have to disconnect all the grounded circuits. This is a herculean effort that would require hundreds of skilled tradesmen. You would have to prioritize and focus the effort, but multi-task. It's a huge job! I don't know whether or not it is too late or not, but these plants cannot be safely shutdown or kept in safe shutdown until you have AC power. That, unfortunately, isn't all that is required. It might have been day 1, but now there is a lot of damaged equipment and high dose rates. If a pilot can't fly over the plant, how can dozens of electricians go to work running temporary wiring?

[divvy]

51. Worst case scenario

The worst case for Japan is that all of Japan has to be evacuated and there is no more Japan. If, as I fear the worst case is that all 6 cores melt down and all 6 fuel pools do,then I doubt there would be any place in Japan that would be suitable to live in for our childrens' lifetimes, or more. China and other nearby countries might also be affected. Like I said, the US should be preparing to evacuate US citizens from Japan. I don't know what the worst case is. On NBC, some official was saying that U4 fuel pool is already empty. I sure hope that is not true. You should be able to tell that from a thermal scan of the building or analysis of the radioactive material coming from the site. I would think that the radiation levels would be very very high on-site if that is true. I guess they are, but I am not smart enough to calculate the worst case radiation levels. The radiation from the site is really not the problem, though. The problem is the spread of radioactive gasses and particulate, not the beta and gamma radiation shine. At least, I think so. Unless I am wrong about the danger, evacuation from Japan is prudent. If you don't need to be there, you shouldn't be there.

[divvy]

52. counterpoint

This seems potentially extreme. The worst case I see is the fuel overheating and melting its way into the earth. It would contaminate groundwater and air. Once they decide this is inevitable, they should be using drilling equipment equipped with liquid nitrogen to freeze the ground around the meltdown sites (the way they do to construct tunnels in soft soil), combined with lots of concrete, to entomb the site as Chernobyl was. Atmospheric contamination is bad, but will disperse quickly.

What you don't have here is a nuclear explosion like Chernobyl, which spread fission products over thousands of square miles, contaminating crops and livestock. If the cores burn their way down to the center of the earth, so be it. I think our focus then is on ring fencing the underground contamination, using drilling and concrete.

I continue to think there are just too many gaps in the information to draw conclusions... even to speculate.

[divvy]

53. decay heat

Fuel elements have decay heat which must be removed. In fact, during operation, about 10% of the heat generated by the fuel actually arises from decay heat -- the energy given off by the waste products of fission as they decay into other isotopes. (90% comes directly from fission.)

After shutdown, the decay heat starts to subside according to the half-lives of the various reactions of the fission products. After 24 hours, it would be about 1% of the heat generated during operation.

That's still a lot of heat, and it must be removed, whether the fuel is still in the core inside the reactor, or whether it is spent fuel which has been removed from the reactor and is being stored on site. "shutdown" reactors still need cooling

[divvy]

54. shutdown cooling system

The fuel removed from a reactor, after about 6 years of use, is stored in a fuel pool. The pool has a demineralizer recirculation system to keep the water clean and the water chemistry good. It also needs quite a bit of cooling. Heat exchangers are used to keep the pool at about 70-90 degF normally. Since the accident, these sysems have been off for lack of any AC power. The pool has gradually heated up and the water is evaporatong... and at this point there may be boiling near the fuel. As the level in the pool drops, the radation level is rising, because water is the shielding that normally keeps the radiation level down... and the rate of heatup in the pool is increasing because there is less water in the pool. The hydrogen fires, at least I think that is what they were, in the pool area probably means that somewhere in the pool, you have fuel clad melting. There would be rapid boiling under these circumstances. The planned backup to fuel pool cooling has always been to put fire water into the pool. They apparently waited too long to start doing it... now the radiation levels are too high to get a person to the refuel floor and some of the fuel may have gotten very hot due to the inadequate cooling. If you boil a pan of water dry... let it set on the burner on high for hours... and then you try to pour water into the pot. What happens? Ahhhh.... think about it! If one or more of the pools is really empty already, it may be too late. no nuclear plant was designed to run without power and operators. It looks like the 3 shutdown plants were left that way for days... this is the result. First the refuel pools... and eventually the cores in the reactors will met down, too. Their cores need a system called shutdown cooling. It is off for lack of power.

[divvy]

55. helicopter drops ineffective?

from NHK news...


Helicopter drops seem to be ineffective. They measured 3782 microseverts/hr of radiation before the water drops and 3752 microseverts/hr of radiation after the water drops. They are preparing to spray the sites with water from the ground. The third reactor's spent fuel pools are evaporating quickly and that is why they dumped so much water on it the first time. They said the pool has 2000(?!) tonnes of water in it and each drop was 7.5 tonnes. Reactor 4s spent fuel pool still has water in it which is why they focused their efforts on reactor 3's spent fuel pool.

[divvy]

56. remaining workers

here is a link to some observations regarding the efforts of the 50 remaining workers:

http://www.nytimes.com/2011/03/16/world/asia/16workers.html?_r=1

I can relate 100% to that article on operators. I would have told my family to drive away from the plant and I would have stayed. I was paid well in the industry and responding to an emergency was part of it. It was just part of doing your job. I am sure that is how those volunteers feel. Apparently, this Utility had built an emergency response facility, but it was not designed for the earth quake. I wonder how they are doing planning and communication. It has to be hard. Unfortunately, I think that the situation calls for more than what has been accomplished to date.

They had a window of opportunity in the first days (and maybe still now) when the levels of radioactivity were still very low to mobilize a large force and execute multiple mitigation strategies. Instead they demobilized...

I hope they've asked the US Navy to do all they can. It's impossible to know exactly just what they could do, though I can play out all kinds of scenarios. But at least bring in a ship or a sub and supply usable power...

[divvy]

61. lessons learned

I am sure there will be cap exp required to address the lessons learned from this disaster. I don't think this is a death blow to nuclear power.xxxxxxxxxxx I think that it is worth noting that every nuclear plant in Japan survived the earthquake. It was the tsunami knocking out the ite emergency generators that put the Japanese plants in great peril. (None of EXC plants have any tsunami risks.) There are lessons learned for all plants, though. Just a couple - 1) you need procedures and standby equipment to deal with 100% loss of AC... that is a big issue for all commercial nuclear plants -- no nuclear plant that I know of can run indefinitely without AC power 2) emergency response facilities, both on and off site, need to be hardened against earthquakes. And I am sure there are more. My response that all of Japan might have to evacuate was a response to - what is the worst case for Japan? It wasn't a prediction that it would happen. Unfortunately, so far... this accident has been pretty much a worst case event. The fuel pool, in it's original state, could have been cooled with bleed and feed of fire water. If a pool has gone dry like the US government is claiming (I would think that there are satellites that give a pretty definitive answer to that), then there could be metal fires, large scale hydrogen production, etc. You couldn't now cool it with a fire hose. It is way too late for that. Large quantities of water is probably the answer, but at least some of these pools are a radiological disaster now. Some can probably be saved by just restoring water level with a hose. All could have been, if action had taken place within hours after the accident, instead of days.

[divvy]

62. roundtable comment

Ah, now I get it. Even though reactors 4, 5 and 6 were shut, the spent fuel still needed to be cooled down using AC power. I thought just submerging the fuel rods in water was enough to capture the decay heat.

So based on your comments, in the absence of AC power, problems with reactors 4, 5 and 5 were inevitable. In that case, shouldn't the Japanese govt have treated all 6 reactors as a high priority right from the start rather than just reactors 1, 2 and 3? It appears they should have mobilized a lot of workers so there were enough of them taking control of every reactor (in-use or not) and making sure they kept replenishing the water levels in absence of power. Of course, hind sight is 20/20, but now it appears the nuclear crisis has been spreading as expected with no real surprises.

The more I understand the situation from hands-on experts like you, I get a nagging feeling the Japanese govt either underestimated the problem or knew things were going to get worse and went in waving the white flag. Conflicting reports from nuclear scientists and journalists from other countries don't help either!

I only hope this crisis comes to a quick end with the least harm done. I salute the courage of the workers trying to get the reactors under control.

[divvy]

63. things to consider

Things to consider when deciding the impact of this disaster on Japan - 1) The disaster is ongoing and no endgame plan is apparent, 2) Large part of population is homeless, death toll is uncertain, 3) all nukes are shutdown and it would be irresponsible to restart them while there are strong aftershocks occurring, 4) a lot of infrastructure, including power lines, has been destroyed 5) rolling blackouts are likely to persist for some time, 6) large population is evacuated or taking cover... almost no traffic in Tokyo except for those fleeing, 7) there is no past example to compare this tragedy to (nobody knows what will happen, because the catastrophe is ongoing), 8) Japanese debt load is already very high and they have been in a 2 decade recession -- now this might be like a war and good for business in the long run, but it is too early to know! With all my heart, I wish the Japanese well. They are truly a peoples of great spirit and inner strength

[divvy]

67. clarification

I never, ever meant to imply that anything about this catastrophe that is a good thing. Please don't scream. Some people think that WWII and the war economy helped end the depression... but it would be insane IMHO to say that WWII was a good thing. The same with this ongoing catastrophe... it would be insane to say there is anything good about it... I have just heard utterances that the rebuilding "boom" might spur the economy out of its recession. I don't know if that might happen or not. Whether it does or not, does not lessen the catastrophe... what I was trying to say is that it is very premature to make an economic thesis. The catastrophe is far from over... we don't even know the best and worst case outcome. The best case gets worse every day these problems aren't brought under control. Even the quiet plants are inching their way toward a disaster as far as I can gather from the news. The worst that could happen is worse than I can imagine. The best case is aweful. The Japanes stock market is down 20% or so... I can't see how that can make it a bargain. The Japanese economy and companies were a lot stronger before this disaster... it is a disaster!

[divvy]

64. Australia and France

Australia and France are recommending that their citizens leave Japan. China has evacuated some of its citizens. Russia is making plans to do so. Military families for our bases are being evacuated from Japan (women and children first). Many commercial airlines are canceling flights into Japan, so there will be fewer flights out. The US is sending planes to assist US citizens trying to leave. The US has recommended 50 mile evacuation zone for its citizens. That need seems to be mostly due to the concerns about U3 and U4 fuel pools. I think they are spooked by the fuel pool danger... I don't know if there is any analysis of such an accident. Dr Chu's own calcs probably have US politicians concerned. They can't afford to significantly under-estimate the hazard. It is better to err on the side of caution. I don't recommend panic like the NY Post, but lying to avoid panic is stupid, because the results of this accident will be readily apparent in due time. Lying just destroys your credibility. If you don't know, just say so... don't say that everything is under control. Emergency response should be conservative on the side of safety

[divvy]

65. History of off-site spent fuel storage

For the history of off-site spent fuel storage, google Yucca Mountain. That is where spent fuel was to go. Commercial storage casks don't require water or any aux systems. That is probably possible with our lower enrichment than military fuel (power plant fuel starts with about 4.5% U235 enrichment... in a sub, it is what? My memory says something like 80%, but I could be very wrong about that number... It would be great if permanent off site storage was an outcome of his disaster, but the Yucca Mountain debate was long, controversial, and failed to arrive at a solution. Most commercial plants are only loading casks to make room for fuel in their full storage pools. The casks are stored inside security fences mostly on-site. They are too heavy to move on roads... I think. There are ways to move fuel, though... I know of a small commercial spnt fuel pool run by GE that is not at a plant... I won't give the location in case a terrorist reads this. It may be public info, but I didn't check.

[divvy]

66. the most critical system in a bwr

The most critical and versatile system in a BWR 3/4 is RHR (residual heat removal system). You can Google this... Wikipedia is very smart. It can do a wide variety of things, but not all at the same time. It has a LPCI mode that can inject into the vessel at low pressures... it can cool the containment with sprays in both the drywell and torus... it can cool the reactor coolant (it has the shutdown cooling mode)... some plants do have a separate shutdown cooling system... it can cool the fuel pool (but needs a spool piece on the ground floor of he RX building installed). There are 2 loops of RHR... getting even 1 loop back would be a huge benefit. Doing so is a lot more than just hooking up power, though. This system has complex controls and interlocks. It is a low pressure system, so you certainly can't use it if you don't have pressure low and under control. The normal fuel pool cooling and normal feed water systems are NSR and normally not seismically qualified. If they are available and can be restored with power, they would be a great benefit. Lighting for workers at night would be very helpful. Installing remote cameras to monitor the systems like the refuel floors would be helpful. Some 120VAC would be helpful to power up the main control room panels and alarms... I am assuming that these control rooms haven't been destroyed... but I can't tell from the pictures I have seen. It is going to require an extensive plan with many electricians to accomplish this. Getting the site dose rates down is probably required before any of these tasks can be attempted. Some plant walkdowns might be required to determine if any of these things are possible... experts may be able to tell from photographs. Replacement systems may have to be installed to perform these functions, but some of them have to be done to stabilize the situation - 1) you have to be able to inject water into the vessel at all pressures being experienced, 2) you need to be able to cool the core to prevent it from re-pressurizing, 3) I assume SBLC has injected Boron... if not, Boron needs to be injected into the core, 4) you need to be able to fill and cool the fuel pool, 5) primary containment should be assessed to see if it is in tact and all necessary valve closures have occurred, 6) you need to be able to cool the suppression pool water (torus)... be able to refill it if necessary. This is the water source for safety system injections and the safety related heat sink. The plants that are relatively stable should definitely have these functions restored asap. It is far easier to do it before severe damage occurs. Working on the most severely damaged plants is not necessarily the highest priority. You have to assess what is possible. All the plants are at risk and reducing the number of catastrophes is worthwhile. All 6 plants are in trouble and need to be assessed for preventative and corrective actions. For example, restoring power will be a lot easier to a relatively undamaged plant. You can't do this without an army of engineers and more workers.

[divvy]

68. not Chernobyl yet

I agree that comparisons to Chernobyl are premature. It isn't as bad as Chernobyl in terms of contamination spread... yet. I wouldn't be inclined to say that it couldn't get that bad, but it isn't yet and I hope it won't be. Nobody has died... I don't think we know the worst possible scenario... there has never been a spent fuel pool in this condition before and I haven't seen or heard any analysis of this scenario. The fuel in the reactors have not breeches their pressure vessels, yet. xxxx There is a wind shift coming. Areas north of the site may be in the fallout plume... a city of 1 million. I think that the radiation fallout that they see will tell us a lot about the severity of this problem for people outside the Japanese evacuation zone. I don't know how long it will take to fill a single fuel pool with those water cannon, but I wonder why they are only doing one at a time. Can't they get more of those fire trucks? xxxx I think I heard that U5 and U6 share a pool, so there are 5 pools that are hot and have low water levels. Even the best possible outcome for this accident is going to require a long time to get these Units in a safe and stable state. The cleanup or decommissioning could take decades. Some kind of structure will have to be built over the fuel pools... the ones with too much radiation to fly over. Hopefully, we will see a big dose reduction as the pools are refilled. New spent fuel cooling and demineralizer systems will probably have to be installed. My guess is that new systems will be easier (and lower dose) to install than repairing the current ones. The reactors would have to have functioning level control, feedwater makeup, and core cooling. The site would need normal off-site power restored and new or repaired emergency generators (tsunami proof this time). Even when things are under control, there is a lot to do... to really end the emergency. The 50 heroes are dedicated to keeping water in the 3 reactors that were running. Engineers should be working on designs for the necessary fixes. Another team should be looking at U4-6 and making sure those reactors are stable. Without core cooling, they won't stay that way forever. Another team should be trying to stabilize the fuel pools. The problems are too serious to focus on just one thing at a time.

[divvy]

69. basic bwr3 and bwr4 design information

from TEPCO http://www.oecd-nea.org/press/2011/BWR-basics_Fukushima.pdf

[divvy]

70. more BWR 4

Many pictures circulating are not of a BWR 4 reactor. There are some more accurate pictures of the reactor and containments here - http://www.oecd-nea.org/press/2011/BWR-basics_Fukushima.pdf ... I agree that adding Boron to the fuel pool would be prudent. The failures that could occur in the fuel pool are not readily apparent to me, but here is an educated guess - 1) severe over-heating causes metal fires, hydrogen generation and fires 2) severe overheating causes fuel tubes to rupture releasing radioactive gasses like K and Sr 3) fuel pellets or bundles form a critical mass starting a nuclear chain reaction, which could cause an explosion (not like a nuclear bomb, like a dirty bomb) 4) enough damage is done to fuel to make ambient dose rates so high that work at the site becomes impossible for humans 5) the fuel pool liner is damaged making it impossible to refill (there are telltale drains on the space below the pool designed to allow detection of a leak from the pool). There is a lot of debate about whether the fuel pool at U4 has any water. I can't believe that we don't have spy satellites capable of measuring the temperature of the fuel in that building... the temperature pretty much answers the question. It should be a fairly easy calc, too... at least for a PhD. I don't know the answer... above my pay grade... and I don't have the reference info I would need

[divvy]

71. radiation chart

I thought a table of radiation exposure effects might be of interest. (Data culled from various sources.)

[divvy]

72. blue glow

Here's a picture of spent fuel being stored in a deep pool. (example only) The blue glow is the well-known Cerenkov radiation. It arises from fission products undergoing (n,p) reactions, i.e. converting neutrons into protons, and emitting an electron (beta particle). Because the beta particle is travelling faster than the speed of light, it emits electromagnetic radiation (light) in a 45-degree angled cone around the direction of its forward path. The frequency of this light happens to be in visible spectrum, and is blue.

nothing can travel faster than the speed of light in vacuum. But the speed of light in water is something like 2/3 of its speed in vacuum. So the beta particles (electrons) emitted can travel faster...and they do, which is what causes the blue radiation.

Yes, adding water and boron is all you have to do... simple in theory. Application, not so easy, when all the equipment is disabled, and it's virtual suicide for anyone to approach the area directly.

A major culprit here, it seems to me, is the practice of storing multiple generations of spent fuel in "temporary" cooling pools on site. No nuke plant is design for long-term storage of spent fuel, right? But there's nowhere else to put it. Very bad planning, and after 50 years of commercial nuke plants, there's been no improvement.

[Yo_Mama]

75. Thanks for that photo

That gives a lot of background for the videos of the fire trucks racing up to try to put water on the fuel pond on 3. They said it takes 1200 tons when full? So far I figured they've put net about 120 tons, but probably only 60 made it in.

Watching it steam off last night was pretty shocking. Something very hot in there!!!

[Paradoxical]

126. Nothing travels faster than the speed of light. Period.

The speed in vacant space is constant. It slows down when matter is introduced to that space; as the electron is absorbed and new ones are spit back out, slowing the speed down.

[Paradoxical]

127. Let me give a better explanation of the speed of light.

An electron behaves like a wave in many ways.

The wave has a relative speed for the front, the collapsing of the wave as it propagates and the rear end of the wave.

The apparent speed of the collapsing portion of the wave can exceed the speed of light in a medium (like water) relative to the movement of the package as a whole. But the electron itself does not travel faster than the speed of light (I assume you mean in a vacuum so it's constant and finite).

[Rex]

285. So if it is traveling faster than light, is it going backward in time too?

Wow, that picture is amazing. To think we 'control' a genie just dying to get out and destroy the ecosystems of the world! Hubris.

[Yo_Mama]

73. That is from the 15th

Currently reported levels are much lower.

NISA is publishing radiation measurements at the 30km border and out. They are HIGH in some places, but they are in the microsieverts. From the 18th readings I saw the highs over 100 microS were limited to a very small area northwest.

Standards say that the public should not be exposed to over 1 milliS a year from a nuke plant. Most people get at least 2-3 milliS a year wherever they live. Quite a few get levels of 5-10 (some areas have higher natural radiation).

So that article from Tuesday was reporting 400 milliS. Levels outside the plant were much lower.

A microsievert is a thousandth of a millisievert. Current readings inside the plant are mostly in microsieverts rather than milliS, although I believe that above the steam emissions they are higher.

Nonetheless, over the last 30 hours the highest reading I saw was 170 microS outside. Even if exposure were to continue for 10 hours straight it would equal 1.7 millisieverts, which is not dangerous to human health, but you wouldn't want to continue exposure at those levels for long.

You can see the measurements being reported yourself at
http://www.mext.go.jp/english/topics/1303717.htm

There is a link there to multiple reading files. You may have to download a Japanese font to be able to open them. Measurements are given in microSieverts.

1 Sievert (acute radiation poisoning begins)= 1,000 milliSieverts = 1,000,000 microSieverts. Those are hourly dosage rates, so multiply by 24 for daily and then 7 for weekly.

If you stay indoors, usually your exposure is cut a great deal - often indoor readings run 10% or so of outdoor readings. However the longer it goes on the more indoor contamination results.

This is just some perspective. I would personally worry about being exposed to doses over 100 milliSieverts, although very little data exists to show that there is a great deal of risk at that level. Some people run annual natural exposures close to that, a lot of people get close to that with radiotherapy plus natural. I think risks begin there, and after exposures between 50-75 milliSieverts in one year I think all additional exposure should be very limited.

Usually radiation workere' exposures are limited to no more than 50 milliSieverts in one year. This appears to be relatively safe.

But 50 milliSieverts = 50,000 microSieverts.

Again, these are high numbers, but it's not an immediate crisis for people in the surrounding areas. The important thing is to get the emissions levels down, because continuous exposure could cause problems.

I think you will get a much better picture of the real exposures if you look at the NISA files.

[BeFree]

74. Fukushima Nuke thread n/t

Bookmarking and a kick

[divvy]

77. graphite reactor burial

I know almost nothing about a graphite reactor, like the one in Chernobyl. I don't think you can just bury 6 BWR's and spent fuel pools. How do you keep the pool full of water and at the same time bury it? If you let it go dry and stay that way, there will be such nasty temperatures that sand and dirt would turn to glass and shatter and cement could never setup. This isn't a Chernobyl reactor... maybe I am wrong, but I don't think that a burial end game is possible. TMI hasn't been buried and I have never heard it suggested. A spent fuel pool is a different "animal." I think it was concern about U4 fuel pool that caused Dr Chu to recommend 50 mile evacuation to Obama. If it was dry yesterday and the fire trucks focused on U3, it doesn't surprise me that the pool bottom has breeched today. I think you will hear a different story about burial tonight... I don't think that is the end game. Nuclear fuel to be buried at storage facilities were to be encased in heavy casks that have self cooling design features. Critical mass? Nooooo... I don't believe they can bury this "dragon"

[jtuck004]

79. Some really good posts.

On that whole burying thing. I think there are at least 3 of the 4 cores haven't opened, one that may have opened...

In the story of Chernobyl they talk about dropping sand, clay, etc, but with boron to absorb the neutrons. But there was nothing in the way once the lid blew off and the building burned.

Here, however, one would have to knock the top off each core, losing the pressure that the water might be under - instant steam bomb -if there is any water. Then again, if there is no water, it likely has molten fuel, in a core designed to survive exactly what is happening. It's made so hard by the lack of protection and what has happend to the fuel stored on the outside of the core.

I agree, the whole sand thing sounds less likely as I read about this - the only answer is to get enough water volume on it to overcome broken fuel storage tanks, which is a lot. You have the problem of putting water on hot, dry material in at least one of those, I think.

And before they go testing all the reactors in the US, they should remember that a test (plus some really, really bad decisions on disabling safeties on the reactor) is what gave us Chernobyl, and based on the reports that we hold much more spent fuel in our reactors than Japan does it might be a better idea to move that stuff our of there first, where possible.

Thank you for your posts.

[divvy]

78. Concise Chernobyl reminder

Interesting reminder of what happened in Chernobyl...

http://www.pbs.org/wgbh/pages/frontline/shows/reaction/readings/chernobyl.html

[divvy]

80. Radiation in California?

Detected radiation in California? EPA says no... others say yes. Doesn't matter. I am sure that at some point the radiation will be detectable almost everywhere. It will be in tiny concentration due to the natural dilution in the atmosphere. Nuke bomb testing was detectable, too. Yes, there should be monitoring, but don't panic. I believe what Obama said in his speech yesterday... I am glad they thought to look at protectorate islands in the pacific ocean. If the situation changes due to a large scale explosion, there would be days of warning for a release to reach the states.. and sheltering would be the worst case protective action... and as I said, that isn't very likely. Nothing is impossible, though. You could get hit crossing the street, too. I would think that there is much better things to worry about.

[divvy]

81. TZ report

http://www.techzone360.com/news/2011/03/18/5387498.htm

In the meantime, GE Hitachi has tapped into a pool of its retirees to build the team of 1,000 experts currently offering advice to Japanese workers trying to contain the disaster. "We're not afraid to call for help from anyone," Danny Roderick, senior vice-president of new plant projects for GEH, told the Financial Times. "We will draw on any resource that will get us to the swiftest answer we can find."

[divvy]

82. more "bury it" stuff

I didn't think I was wrong. Surprised that so many are repeating this "we may have to bury it" stuff. EXC (Exelon- formerly Commonwealth Edison and PECO) owns and operates TM-1. The upgrade in the severity to equal TMI? Get serious, it passed TMI days ago. All they had to cleanup at TMI was one core worth of fuel. This cleanup will be at least 10 times as big as TMI... assuming we have seen the worst of the event. While everything seemed quiet today, I am not sure anything got any better. There is a diesel running at U5/6... but we don't know if core and fuel pool cooling have been restored. They are trying to hook up offsite power to U2, but turning on the power will be tricky and we don't know what systems can still run. They have been spraying water into U2 fuel pool. Can somebody explain to me why they haven't flown one of those little radio controlled helicopters into the buildings to see the fuel pools and the levels? Is that so hard? I think that people are growing weary of the news, but this problem is not going away... the situation has not been stabilized.

[defendandprotect]

83. kr

[divvy]

84. bury to control radiation

On NBC news tonight, they talked of a plan to fill U4 pool, if it won't hold water, with sand as an interim measure to try to reduce the dose given off by the pool. Said it was being proposed by US and resisted by Japanese. That is different than burying the site "like Chernobyl." Actually, tonight they showed Chernobyl. It isn't buried... they are currently building a new containment building around the structure.

[divvy]

85. getting fuel pool cooling working

Getting fuel pool cooling working... 1) suction for pumps has a stand pipe to ome off high in the pool (to prevent any chance of accidentally draining the pool)... pool would have to be nearly full to use it 2) piping and regular power is NSR, non-seismic... probably broke and 3) some of the pools are full of debris from roof... would quickly plug pumps or block suction and 4) these pumps aren't designed to pump very hot water and 5) some plants show service water pumps inop. This system is only an option at the plants with less damage... RHR could possibly be used for pool cooling.

[divvy]

86. CTBTO

The first publicly released "professional" projection for fallout hitting the US was, I believe, from the CTBTO and reported by the New York Times on March 16th.

Earlier today I saw reports that a diplomat with access to the CTBTO radiation tracking data told the AP that tiny amounts of radiation had reached and been detected in California.

Later on in the day I saw reports that the EPA was questioned about fallout having been detected and they confirmed it.

A WSJ article from a couple of hours ago reported that a CA radiation monitor had "validated" readings seen in Washington state on March 16th and March 17th.

IOW, it sounds as though we have the CTBTO and a foreign diplomat to thank for knowing what little we know now.

[Yo_Mama]

89. It's nothing for us, but Tokyo's in the line of fire this weekend.

ZAMG's simulation page
http://www.zamg.ac.at/aktuell/index.php?seite=1&artikel=ZAMG_2011-03-18GMT09:52

That link has great animated maps. But it is in German.

At the bottom of that page there is a link to an English pdf that will give you scaling:
http://www.zamg.ac.at/docs/aktuell/20110318_Japan_1300_engl.pdf

This is utterly unthreatening to the US. Or to Europe. Only the top two color brackets in the simulation really relate to human damage.

But in a month? Six weeks? Once water sources for Tokyo begin picking up significant contamination, it's hard to see the way out. You can't evacuate tens of millions of people - there is nowhere in Japan for them to go! And the total load just keeps building.

So they will have to do whatever to chop the emissions down. If they can buy enough time to get some of the spent fuel out the net situation gets better.

I think they go to the next level by Monday if the winds shift toward Tokyo. They already had northwest readings of over 100 microSieverts an hour (multiples) at the 30 km border yesterday. The wind was blowing that way then.

[divvy]

87. TEPCO spent fuel storage

http://criepi.denken.or.jp/result/event/seminar/2010/issf/pdf/6-1_powerpoint.pdf

I first saw this link here, but have lost track of which thread.

[Yo_Mama]

88. Divvy, they are sending some sort of special concrete trucks

My guess is this an attempt to patch 3 right now. They said something about "aerial", but it might be a truck that pumps a few stories up.

It was a brief mention when they were running down the extra firemen being shipped in.

They've raised the one-shift limit to 150 milliS. NHK reported 10 milliS at 1 and 15 milliS at 2 today. The 500 meters out point was lower, but I think the winds have shifted. However it sounds like once you pass 100 milliS at the end of your shift, you don't go back in.

Since they've got the pump working at 5 the temp in the spent fuel pool is dropping.

I think they're just trying to get radiation emissions lower so they can continue to work. If the levels keep going higher, it will shortly get to the point at which they can't put people in there at all.

The battle now is just to mitigate in whatever way they can. Since the common storage pool is intact, you'd think they'd try to get that out even if they had to slag one or more of the active reactors.

Still smoking out of 2's blow-out panel, still smoking at 3. No data on 4.

Wind is projected to shift toward Tokyo by Sunday. They are evacuating hospitals within the 30 km boundary.

[divvy]

91. Thank you

Let's all wish them the best of luck and circumstance.

[divvy]

92. self-delete

posted in the wrong spot

[divvy]

90. WSJ article

http://online.wsj.com/article/SB10001424052748704608504576207912642629904.html?mod=djemalertNEWS

That's a bit shocking, but my background was where safety was always Priority #1, performance was #2 and cost was #3. I'm sure people will be doing post-mortems on this for a while, and I'm sure there will be valuable lessons learned for the industry. What jolts me is that you don't expect such mismanagement from Japan, where you can set your watch by the trains.

The differences in the emergency response that would occur in the US and what appears to have happened in Japan are too numerous to list here. To hear that Tepco wanted to walk away from the problem and hand it off to anyone, including their government, is shocking, if true. I am amazed... it is so out of character for the Japanese... look at how their people are responding! We haven't really heard much about the Japanese emergency response team, but the WSJ article is pretty disturbing. Hope it isn't true. Following a nuclear accident, there is no time for bickering or hesitation to implement emergency procedures. It is a race against time. (IF THIS REPORT IS NOT TRUE, IT IS SLANDER!) If it is true, Tepco should have to answer for it's misconduct once the crisis is over. If they are mishandling the situation, the Japanese version of the NRC should be looking over their shoulders. In the US, there would be a state regulator and NRC team all over the accident with real time input into the situation... but the utility is in operational command. I have been watching Rachel's coverage. It has been first rate IMHO. Her coverage from the oil spill in the gulf was outstanding, too

[divvy]

94. Japan vs the company

To understand the situation of Japanese people vs the company, we need to understand how the company managements have acted. I have worked with many Japanese co-workers and Japanese companies in various assignments in the past. From what I saw, the Japanese workers are very sincere and thorough. I would not say the same about the Japanese companies & their management teams.

The companies have the spirit that the govt takes care of the "big issues". In the xxxxxx industry where I worked, it was the govt ministry (xxxxx) that did most of the planning and dealing with big issues, then companies just came in an built or followed govt leadership. The Japanese company management teams were never able to have strategic thinking or "out of the box" thinking because they were always guided by the big hand of govt.

That kind of company attitude does not help, and in fact hinders, in life & death emergencies like this one. I am not surprised that TEPCO tried to push this off to the govt..

[divvy]

95. Nuclear response are complicated

Nuclear responses are too complicated to not be thoroughly planned for. You need to have personnel that have trained and drilled for it. As a member of our plants emergency response teams (4 teams had 24/7 coverage), there were administrative and technical procedures... and we trained for it including an emergency drill at least once a year. The drill included communication with all nearby county, state, and federal entities... oversite by the NRC, etc etc. You have to have people that are nuclear trained and familiar with the plant. It would be nearly impossible for an outsider to just come in and take charge of a plant in an emergency. Even, if for one second, we were to assume that the government was going to take charge... plant personnel and expertise would still be required. You have to have many disciplines in the team - plant engineers with mechanical, electrical, and nuclear expertise, operators, chemist, rad techs, maintenance people, plant security, plant IT, etc etc. You can't just say it is a mess, your problem, and walk away. Whatever the emergency response plan was, it should have been clear about command and control. Sad... I have always wondered about nuclear plants in third world countries or even just small countries... they can't really be prepared for emergencies. I am surprised that the Japanese weren't better prepared than these stories would imply. I do agree with the Prime Minister comments that these workers are fighting for the nation's survival. There is news this morning that 2 holes have been drilled into the reactor (secondary containment building) to allow release of hydrogen. Hydrogen is only a problem if you have melting zinc cladding somewhere.

[divvy]

96. Company level, not plant level

I agree in many aspects that the companies that have nuclear emergency trained workforce have to do this and not push it onto strangers to that piece of hardware (govt or Reg commission etc). That is precisely my point that TEPCO management seemed incapable of taking on, even though their workers were, I am sure, trained well in emergency procedures.

My comment about "out of the box" thinking was just for planning for worse case scenario at the company level, not at the plant level. What I was suggesting was that there would have been resistance, for example from, company management to pump seawater at an earlier time when the emergency was not as acute. Of course, I don't know if that happened, but I am suggesting a lack of foresight and proper planning at the company level ..

[divvy]

97. disaster affected TEPCO employees too

Not trying to defend TEPCO's actions, (just my two cents) but isn't reasonable to assume that some of their employees from the Fukashima facility were unfortunately among the 10,000+ casualties in the tsunami? I would have to assume that employees lived fairly close to the 'office', and that was the hardest hit area, correct? Entire towns were wiped out. My guess is that they lost a good portion of their employees in this disaster. Not sure what percentage of their disaster plans would have covered missing or dead employees.

If that is the case, I am sure they could have, and probably did, move employees from their other nuclear facitlities in to help out on this one. But that involves logistics. I can only guess that involved tracking down employees of the Fukashima facility, and perhaps not even getting responses in a lot of cases (if they were even able to communicate due to disabled infrastructure). This would have taken hours and perhaps days in some cases, perhaps at the most critical time.

As stated earlier, even disaster plans have their assumptions. Unfortunately, the scope of this disaster was 'off the chart'. Lessons are being learned.

[divvy]

98. the "50" were heroes

No, I didn't mean zinc .., I typed "zirc" which my iPad automatically changes to "zinc." Spell check is a nuisance sometimes. I wish it would ask me to make the change, but it doesn't. you are right that the Japanese were up against an extremely difficult situation... extremely difficult. I really don't understand their reluctance to take charge... I think that too many people were evacuated... I think they lost control of their people, because the place they were to go was damaged (some people may have been killed, because the "walked" into a tsunami)... Bottom line, it was their duty to respond promptly to the crisis. Any suggestion by them that someone else should is really bad on many levels (I can understand asking for help... I can even understand asking for a crisis manager... I can't understand wanting to pull their people and have somebody else address the problem). Finally, there were things they could have done to reduce the damage done to the plant. It seems like all they could do was address the most urgent of their problems... and other things that needed done were not addressed for days when they too became urgent problems. If they needed technical or manpower help, they should have been asking for it early. Japan had a lot of nuclear plants that didn't "melt down"... there were a lot of nuclear trained personnel at those other plants... they should have had GE and Toshiba on the phone immediately (and if they needed satellite phones, they should have asked their government or military to get them to the command center and site). Bottom line is that there apparently was total confusion and no plan... that is not what a good post accident response is supposed to look like. You can say it was perhaps understandable, but you train so that doesn't happen. I would like to say that there was nothing they could have done, but I think that U4, U5, and U6 did not have to meltdown... but it was inevitable when their operating crews left them unattended. None of those fuel pools had to overheat to the point of fuel melt, but it was inevitable when you let them set there for days without adding any water to them. The "50" are heroes, but more was required. It wasn't their fault, but it was somebody's. Japan has people that could have helped a lot. Days after the event started there should have been hundreds, if not thousands of people supporting them... doesn't seem to have happened. I am surprised and disappointed. Their country and the nuclear industry depended on them (the utility and its regulator oversite) to do their jobs to a high level of professionalism.

[divvy]

103. actually, it is rocket science

Actually, it is rocket science--or rather nuclear science, which is even more difficult.

I imagine things were effectively out of control from the very beginning. Even if you plan for emergencies, the plan assumes certain parameters. A plan designed for an earthquake up to 8.0 fails at 9.0; a plan designed for a 10-meter tsunami fails with a 30-meter tsunami. Apparently, the ability of engineers to assess (much less repair) damage was overwhelmed from the very start. But there should have been someone at company headquarters whose primary and immediate concern was to come up with a comprehensive Plan D, taking into account everything that could be at risk once Plan A, Plan B, and Plan C were shredded.

[divvy]

121. broader media

The broader media, in my view, has done a poor job of covering this event. I just think they are "nuclear" illiterate and so do not know how to present the information - or grade its importance. . . still one would think that there are some protocols they could be following so that the public is given updates.

[JohnyCanuck]

309. I'll take this with a grain of salt.

The differences in the emergency response that would occur in the US and what appears to have happened in Japan are too numerous to list here...

Greg Palast doesn't seem overflowing with optimism that similar problems would all be resolved with clockwork precision in the USA.

Nuclear plants the world over must be certified for what is called "SQ" or "Seismic Qualification." That is, the owners swear that all components are designed for the maximum conceivable shaking event, be it from an earthquake or an exploding Christmas card from Al Qaeda.

The most inexpensive way to meet your SQ is to lie. The industry does it all the time. The government team I worked with caught them once, in 1988, at the Shoreham plant in New York. Correcting the SQ problem at Shoreham would have cost a cool billion, so engineers were told to change the tests from 'failed' to 'passed.'

snip

Am I on some kind of xenophobic anti-Nippon crusade? No. In fact, I'm far more frightened by the American operators in the South Texas nuclear project, especially Shaw. Stone & Webster, now the Shaw nuclear division, was also the firm that conspired to fake the EDG tests in New York. (The company's other exploits have been exposed by their former consultant, John Perkins, in his book, Confessions of an Economic Hit Man.)
If the planet wants to shiver, consider this: Toshiba and Shaw have recently signed a deal to become world-wide partners in the construction of nuclear stations.

The other characters involved at the South Texas Plant that Obama is backing should also give you the willies. But as I'm in the middle of investigating the American partners, I'll save that for another day.

http://www.gregpalast.com/no-bs-info-on-japan-nuclearobama-invites-tokyo-electric-to-build-us-nukes-with-taxpayer-funds/

[divvy]

93. HCPI, RCIC, or ADS

Following a loss of AC power, the plant should have had HPCI and RCIC or ADS functional. Our plant has a Safe Shutdown system that would have been functional. Most plants don't have this system, though. All of these systems have their limitations and may have been damaged by events like in Japan. Immediate responses by operators would have been to insure their operation and assess the capability of getting emergency diesels on. Usually, wthin 30-60 minutes command and control would be transferred to an onsite or offside emergency response center. I heard that the onsite one was destroyed... if the offsite one or the corporate one had no communication, then their emergency response planning and facilities were inadequate. I believe we would do better than that in the US, but there is no doubt that a level 9 earthquake and tsunami is a worst case event. To say it wasn't a maximum challenge is not understanding the situation. Go back to my first couple posts... I said they were in the fight of their lives and needed our prayers. They were..

[divvy]

99. phoenix aircraft

If I lived in Japan, I wouldn't drink the milk. Fresh veggies and fruit should be peeled or thoroughly cleaned... canned or frozen prior to the accident would be better. Pregnant women and babies should be at 50 miles plus from the accident. Everyone that doesn't need to be in Japan and can leave should leave... There apparently are multiple, conflicting predictions about the ramifications of letting a fuel pool go dry. It is unknown whether or not the fuel cladding will burn. I suspect that there are US military satellites capable of monitoring the pool temperatures. It is my understanding that one of the two Phoenix aircraft has been sent to Japan to assess the risks ... http://en.wikipedia.org/wiki/Boeing_WC-135_Constant_Phoenix

[divvy]

101. phoenix yes

Yes, I think it is a safe bet that more than one space platform is capable of some helpful imaging. Supposedly, a Constant Phoenix was moved from Offutt (NE) to Eielson (AK) on Tuesday to prepare for its first sniffing mission. So that mission happened on Wednesday or Thursday(?). Presumably, it was sniffing on the way to Eielson and sniffing on its way out from there so we may have gotten some read on what was already headed our way. A Global Hawk supposedly first overflew the reactor on Wednesday. A U-2 was supposedly also being used by Wednesday. That is above and beyond the USS Ronald Reagan and its aircraft, other US forces in the region, and Japanese forces... all capable of flying sorties with platforms that have thermal, etc imaging.

[divvy]

100. daily telephone media briefings

"Japan Nuclear Power Crisis: Daily Telephone Media Briefings"

http://www.ucsusa.org/nuclear_power/nuclear_power_risk/safety/japan-nuclear-crisis-briefings.html

[divvy]

102. U5 and U6

It is certainly good news if U5,6 are in cold shutdown. I believe that they brought in an emergency generator to restore power to the shutdown cooling system. I wish we were hearing more details of the battle to save Japan, as their Prime Minister called it. These Units need to have 1) a hard AC power line connected, 2) refilled fuel pool, and fuel pool cooling re-established. Then we could say U5,6 has been stabilized. I don't mean to make light of the progress that has been made... any progress is a welcome change... but even the plants in the best condition are not stable yet, little alone safe. Even essential functions are still absent, little alone having any redundancy to prevent plunging the plant back into crisis. I follow the Union of Concerned Scientist positions, but I am not aligned with all their positions. I worry about an industry policy to take 40 year old plants, invest a few million dollars, "goosing" up the power, and relicensing the plants for additional decades of operation... instead of building new, safer plants. As the nuclear plants in the US age and they are run at high power outputs, I think an accident is likely. The good thing is that I think our operators and technical support are very well trained, as is apparent from the fact that these plants have become more efficient (running at full power with less downtime for maintenance) as they age... not less so. A good response can do much to mitigate an accident. We just aren't doing the right things in this country, because we don't have an intelligent energy policy. Our politic is bipolar.

[Yo_Mama]

106. The latest reports on 5 or 6

are really good.

Much lower fuel pond temps, controlled pressures in the reactor and containment vessels.

[divvy]

104. unscheduled scram

Once I was driving home about 11pm during a snowstorm, having informed my wife I was home-bound, after working with a team on a nuclear problem occurring at a nuclear prototype site in upstate NY (unscheduled scram). We had no cell phones then. A car came up behind me flashing its high beams frantically. I pulled over; it was my boss, asking that we go directly to the site and enter the reactor.

We went, suited up in protective gear, and went to inspect the top of the reactor. From there, I called my wife via the site communications and advised here where I was. She was surely baffled.

<snip>

Oh, those nuclear power days...miss them sometimes. But not the old codger named Admiral Rickover to whom I indirectly reported in QA.
BTW...xxxxx working out of the Washington DC area, was often part of those assessment teams! The Admiral would actually give him a swift kick, if needed

[divvy]

105. insurance

nikkei.com reports

• 02:12 - Payouts Seen Reaching Y1tln On Earthquake Policies

That is about $12.5 billion. May be not everyone had "earthquake policies".

I have seen preliminary estimates of damages at $200 billion, and if only $12.5 billion is covered by insurance, that is bad news.
It could be that the insurance companies will distinguish between earthquake damage, tsunami damage and nuclear radiation damage.

In the US, there were lot of controversies about Katrina damages too.

In the San Francisco earthquake of 1906, it was the opposite problem. No one had earthquake insurance, but many had fire insurance. Some buildings that were totalled by the quake were intentionally set on fire to hide the quake damage and let the owner collect the insurance.
But it will be hard to claim quake damage after the house is completely demolished by a tsunami. And every policy I've ever seen excludes nuclear radiation damage (to houses).

And we haven't begun to see damages to health from radiation. It's going to be a long, long slog for the insurance adjusters.

[divvy]

115. self-insurance

This nuclear accident is at least an order of magnitude more difficult to deal with than TMI. The spread of radiation has been far worse than TMI. The operational response has been far more difficult. The economic cost to decommission the plants will be far worse than TMI. The US nuclear plants set aside money as self-insurance in the case of an accident. This picks up some or all of the cost, because the operating company will almost certainly be bankrupt. I don't know if the Japanese nuclear industry has similar insurance.

[divvy]

116. $10 billion

US plants are only insured up to $10bil... for more on insurance, go to the following link and scroll down to insurance...

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

I suspect that the Japanese government/tax payers will have to pick up most of the cost.

[divvy]

117. catastrophic nuclear indemnity

There is catostrophic nuclear indemnity for the US nuclear reactors.

http://en.wikipedia.org/wiki/Price%E2%80%93Anderson_Nuclear_Industries_Indemnity_Act

[divvy]

119. global nuclear pool

Most Japanese property insurance policies do cover earthquake, but some do not. It's a mixture.

The nuclear plants are of course insured through a nuclear pool, which is shared by other nuclear pools around the world.

[divvy]

107. restart 1 & 2?

I read in this morning's WSJ that they are going to restart reactors 1 and 2 to start generating electricity. This frankly amazes me. After a loss of cooling accident I would have assumed these cores would be history...or at least subject to very extensive testing prior to restart.

[divvy]

108. I can't believe that

Restart U1 and U2? Aren't their Reactor Buildings badly damaged? No redundant sources of offsite power? No redundant diesels for emergency power? I can't believe that! This morning I woke up to news that they had drilled 2 holes in a reactor to vent hydrogen... my jaw dropped to the floor until I thought about it... that is impossible! The crane would be needed to even get close to the reactor head... and the dose rates would be off the charts if you pulled the shield plugs to access the reactor head. They must have meant they knocked some holes in the reactor building, not the reactor. I can't believe that Units 1-3 will ever run again... and maybe none of them. You are right, xxxx... you would have to sample the coolant and probably "sip" the core to check for fuel leaks. There is no way they can meet their technical specifications for a startup... they put saltwater in the reactors! No way... not even in an emergency.

They probably just meant that they hooked up AC and were going to startup some systems... somebody took that info and said they were going to restate the reactor. Big difference.

[Hannah Bell]

110. i think you should link the source. i haven't heard anything like that.

[Hannah Bell]

109. ...

[divvy]

111. 212 degree F

Actually, there is some good reporting on the situation. I think that the reports referenced above are just imprecise and incorrect language by news sources... I have only watched CNN, the evening NBC news, and Rachel Maddow's show for coverage of the events... so I can't comment on other sources. What I have been watching has been reasonably accurate about the events and the dangers. I do think that over the weekend, the news seemed to shutdown somewhat. That made getting updated info nearly impossible. It is also true that the news networks, especially CNN, tends to be "single minded." For awhile, the only news you got was from Japan... now the focus has moved to the middle east. I am glad that the infrared scans of the pools were good, if that is the case. Water can't be over 212degF, unless it is pressurized... so saying that temps are not above 212 really only says that there is some water in the pool and it is at least covering the fuel. In the case where there was concern about the pool integrity, that is very good news. Better news would be getting the pool water temperature well below 212, where the evaporation and volatile gassing would be reduced. There are 2 main release pathes taking place. Venting from the reactor and primary containment should be through the plant stack. This is the plume that the navy helicopters and ships experienced. This release is most dangerous when the prevailing winds are toward land, instead of to sea. There are also uncontrolled ground level releases... I think that he fuel pools are the worst sources of these releases. It is made worse by fires and hydrogen explosions, as this tends to "stir up" the contaminated material. These are the sources of the radiation spikes that have forced the heroes to periodically have to back off from the site.

[divvy]

112. bankruptcy

I am sure the utility will declare bankruptcy... I assume that Japan has bankruptcy laws. Governments are fragile in Japan... it is probably too early to know whether this Prime Minister will survive the crisis. I would think that Japanese lost production would benefit other Asian counties. Taiwan is an alternative source for electronics. Australia will provide raw materials for rebuilding. The strong Yen should help Japan import its rebuilding material and equipment. The Japanese are great savers, but they won't be doing much of that for awhile... they will be spending those savings to rebuild. They will need electrical generating equipment... seems like it might be a good time to build some offshore wind farms.

[divvy]

219. TEPCO investors may be wiped out

TEPCO investors may be wiped out

http://www.bloomberg.com/news/2011-03-30/tokyo-electric-investors-may-be-wiped-out-after-nuclear-radiation-crisis.html

[divvy]

113. controversial practice

"The Fukushima Daiichi power plant was already one of the most trouble-prone nuclear facilities in Japan, even before the devastating earthquake and tsunami that knocked out its cooling systems and precipitated the worst nuclear crisis in 25 years, a Wall Street Journal analysis of regulatory documents shows.

In addition, a standard practice at Japanese nuclear plants—to remove fresh fuel from a reactor and park it for weeks or months in a less-protected "spent fuel" pool during maintenance—appears to have been a significant contributor to the crisis, engineers say."

Interestingly, at the time of the quake, Reactor 4 was offline and all the fuel rods had been transferred to the spent-fuel pool. Apparently, this is not done in the US and is considered to be a controversial practice.

http://online.wsj.com/article/SB10001424052748704433904576212980463881792.html?mod=djemalertNEWS

[divvy]

114. water

We don't know for sure where all of the water is going. A lot of it is going into the air as vapor... either as steam or evaporation. The only cooling going on in the pool is to add cold water as water is blead off (either because of vapor or overflow). I see no evidence of any pools overflowing with water. Some of the sprayed water is missing the pool and either spilling out on the ground or ending up in the reactor building basement. The latter could be a challenge to recovering from the event. Sump pumps have no power. At our plant, the emergency core cooling pumps were all in water tight rooms in the Reactor Building basement outside the torus with submarine doors into the pump rooms. Those pumps would be needed to restore core and fuel pool cooling. As far as whether or not the pools are leaking. I believe this would be true -- Under the pool is a concrete structure. This space has many telltale drains installed with site glasses. The only way that I know to tell if the pool has a leak is to check those telltale drains either visually or the radiation level near these drains... if there is a leak, these drains would be screamingly radioactive. The fact that they are still spraying water is more of a function of the fact that there are 5 fuel pools and they waited a long time to start. Until fuel pool cooling is restored, and I am not optimistic of that happening soon, they will have to keep spraying. The goal in spraying is to both fill the pool and cool it. The cooler it is, the less will be the evaporation rate... the lower the dose rate... the less the spread of contamination. Eventually, a building will have be built around the fuel pools... like the one at Chernobyl.

[divvy]

118. Japanese politics may change

http://finance.yahoo.com/tech-ticker/article/536054/The-Politics-of-Japans-Crisis%3A-PM-Kans-Govt.-%22Very-Well-Could-Fall%2C%22-Chang-Says

"It's Tuesday morning in Japan as I write this and the situation remains ever-changing, but the news Monday is likely to reinforce the credibility gap facing Japan's government and Prime Minister Naoto Kan."

[divvy]

122. thermal imaging

Perhaps most are aware by now, but in case some aren't... thermal images are being released. A few can be found here:

http://www.zerohedge.com/article/thermal-images-fukushima-indicate-blistering-128-degrees-celsius-zone-reactor-3

[divvy]

123. pretty awful reporting

Pretty awful reporting. They look at a thermal image and make absurd accusations of who is lying about what, because one area shows 128C and another was alleged to be under 100C. Obviously the fuel (core), reactor (vessel, head, internals), reflectors, shielding, piping, and water would all be different temperatures. Indeed, without a temperature gradient there is no heat flow (tell those journalists to Google "Fourier's Law (of heat conduction)." Pathetic journalism.

[divvy]

124. reference/calibration gradient

FWIW, I too found that Tyler Durden (don't know how many of them there are) commentary lacking and for that matter even the original images. A reference/calibration gradient would be nice... an overlay of the underlying reactor components/areas would be nice. In any case, it is something and if those got released perhaps there is more to be found if someone digs.

[divvy]

125. the top image

the top image looks like a building full of super-heated air; pretty hard to tell without a calibration gradient

[divvy]

128. no proof of lies

If anyone has declared this accident over, then they are wrong... I haven't heard it lately, but I did hear one supposed expert say that this event wouldn 't be as bad as Chernobyl, because these reactors have containments. BUT the secondary containments around the spent fuel pools have been destroyed... and venting of primary containment and the reactor has taken place, because there is no containment cooling (venting is the only way to lower pressure). It may or may not be as bad as Chernobyl... the story on that is still out. If it isn't as bad, it will be for xxxxx’s reason (#52)... not that there is a containment. No containment around those spent fuel pools is a big problem for containing contamination.

I didn't see any proof of lies in the thermal images. The reactor vessel would be above 212, for sure. It would be interesting to see the images during a reported fire... to see what is actually burning. I am surprised that the contamination spread is so noticeable in the ocean. Really? Should be pretty diluted.

[divvy]

129. cause of high dose rates

What is causing the very high dose rates onsite of the reactors? I ask, because I don't know, but I think it is important to know. We know that there were reports of smoke and steam clouds at the time of the dose spikes. The human toll on the volunteer heroes of these spikes has been great. It also makes progress on repairing site equipment very difficult... and it is likely a major contributor to the contamination spread from the site. They need to get a handle on what this is... I am surprised that they haven't gotten cameras onto the refuel floors and other parts of the plants. If the workers can't stay onsite, they can't keep the situation stable and try to make it better.

[divvy]

137. dose rates

http://www.nytimes.com/2011/03/23/world/asia/23japan.html?_r=1&ref=asia xxxx So, apparently they know that the problem elevating the site dose rates is the spent fuel pools. As I said, spraying water into the pool will b

[divvy]

138. the 5 pools

http://www.nytimes.com/2011/03/23/world/asia/23japan.html?_r=1&ref=asia xxxxxxx Frequent spraying water into the 5 pools will be required to cool them, not just keep them full... though they won't stay full if you don't cool them. I doubt that very much of the contamination of the ocean near the site is coming from runoff. It is probably the release of radioactive gas and vapor that falls back to earth or the sea. To minimize releases, they need to keep those pools cool and nearly full... all 5 of them. I would think that a water hose could be fixed to a ladder truck and moved into position for spraying into each of the pools ... to reduce the exposure. More fire trucks shouldn't be an issue. Sudden increases in dose that can and have become lethal in the absence of worker evacuation are really bad on many levels. So what going on in the pool actually causes the spike? My guess it is either uncovering fuel or fuel rods getting so hot that they break open releasing the radioactove gases normally retained inside the rod. The fix to either one is more cooling... and it needs to be nearly continually maintained. Just yesterday, there was debate about what the pool thermal scans meant. The answer seems to be that more pool cooling is required. In working to get reactor core cooling running (after reconnecting AC), I hope they have checked to see if the reactor building basement is flooded (I suspect it is, but how badly?). Pumps or motors can't be replaced if the building is flooded. We haven't heard what the electrical system "looks" like... what systems can maybe be powered up. In some cases, it may be lower exposure to design and install new systems than repair the original, damaged ones. For example, it should be possible to inject clean water into the vessel, instead of salt water. Where functions are being performed by diesel or battery powered systems, more reliable AC systems could be added. I understand that perhaps their was a lot of problems with the initial emergency response, but command and control should be improving, including the release of info to the public. I have to ask why the info isn't getting out... is good info not being released or is press not asking the good questions?

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139. core coolant sample

The Japanese should be able to take samples of the core coolant at some point... may need to restore some power. At our plant, we had a High Rad Sample System that had been retrofitted to the plant many years ago. It is a system designed to pull highly radioactive samples post accident. A water sample could give a great deal of insight into the core condition... and I bet the pH of the coolant water is scary. The huge chloride excursion from injecting salt water... and these coolant temperatures... not good! ... that info should go to damage assessment. About those fires... at least one of the plants had a roof collapse into the pool. If these roofing materials get in close proximity to hot fuel, that could explain the fires and smoke... asphalt and similar materials could be burning.

[divvy]

140. sodium-24

I wonder (aloud) if they have to contend with sodium-24 radioactivity. When the Navy designed the original Seawolf submarine reactor, which was sodium cooled, it had to provide heavy shielding because of sodium-24 which has a short half-life (15 hours) but emits a strong gamma ray. Is it possible that enough seawater has passed through the core to result in a significant amount of Na-24 production? Not a long-term problem, though, because of the short half-life.

[divvy]

141. chlorides

Why are chlorides bad? For one, relatively fast crack growth.

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130. seawater

"Engineers have been spraying the coastal complex with thousands of tonnes of sea water so fuel rods will not overheat and emit more radiation.

Najmedin Meshkati, a nuclear and environmental expert at the University of Southern California Los Angeles, said the measures were necessary but raised a fresh, and serious, concern.

"Where does the sea water drain?" he asked. "This is now radioactive waste water. Has there been any measurement of its radiation effect?

"I am interested to know how this water is being disposed, if it is being disposed or just allowed to drain to sea. That is the hidden part of this catastrophe." Japanese authorities have acknowledged that some of the water may be spilling into the ocean, but said they doubted it would have any effect on human health. They agreed it needed to be monitored."

http://www.france24.com/en/20110321-hopes-rise-power-restored-fukushima-reactors-tsunami-earthquake-japan-nuclear

MEANWHILE, Tepco plans to study seawater radioactivity that it is causing:

http://english.kyodonews.jp/news/2011/03/80061.html

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131. pretty small dose

From the article quoted: "It would have to be drunk for a whole year in order to accumulate to one millisievert," a TEPCO official told reporters in Tokyo.

1 mSv = 100 mrem. That is 2% of the maximum annual occupational limit for nuclear industry worker.

Average background radiation is 300-350 mrem/year.

Smoking one pack of cigarettes a day gives an individual about 870 mrem per year.

You get about 40 mrem/year just from the potassium-40 in bananas and Pb-210 and Po-210 in other food, milk and water.

You get 2 mrem/year sleeping next to someone.

You get 7 mrem/year living in a stone or brick home.

You get 120 mrem/year if you work in Grand Central Station in New York City. (It's granite walls have a high uranium content.)

[divvy]

132. brazil nuts

Incidentally, Brazil nuts are over 1000 times more radioactive than other foods because of their high radium content.

Anybody spread fertilizer around their garden? One kg of fertilizer emits over 5,000 Bequerel (disintegrations/sec) of radiation due to Potassium-40. Compare to some other common, radioactive substances:

Human beings: 100 Bq/kg
Bananas: 130 Bq/kg
Brazil nuts: 207 Bq/kg
Granite kitchen countertop: 1000 Bq/k

[divvy]

133. potassium-40

According to Wikipedia, Potassium-40 is a natural occurring radioactive isotope in animals and people. Isn't that different than Cesium-137 or Iodine-131? Wikipedia didn't note any health affects from Potassium-40 exposure.

"Potassium-40 is the largest source of natural radioactivity in animals and people. An adult human body contains about 160 grams of potassium, of which a small fraction is potassium-40. From the isotope abundance and half-life it can be calculated that this produces, within our bodies, about 300,000 disintegrations per minute, 24 hours a day, all our lives."

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134. radon

The effects of radiation are the same whether the isotope is naturally occurring or man-made. You ever hear of radon?

The effects are also independent of the isotope; they depend only on the type and energy of the radiation (alpha, beta, X-Ray, gamma etc.) and the part of the body which receives the dose. Sv and Rem are modified units which apply to human exposures; they take pure energy dosages (e.g., 1 rad = the amount of radiation which deposits 100 ergs of energy in one gram of matter) and multiply by a weighting factor according to the kind of radiation and the degree of tissue damage it causes.

[divvy]

135. other isotopes

Yes but the parts of the body which receive a dose and how large that dose is can be affected by the type of isotope. Which can make the actual effects dependent on the isotope!

Potassium-40 is in all our bodies radiating our tissues. However, I think its concentration is automatically regulated along with ordinary Potassium (the amount basically remains constant even if we are exposed to more), it is fairly uniformly distributed, and it isn't chemically toxic. Other radioactive isotopes aren't so friendly... at least some of them can't be regulated by the body, they do concentrate in sensitive organs/tissues, and they are chemically toxic.

Put another way, I think it is fair to say we are constantly exposed to the risk from Potassium-40 but it is also fair to say that other isotopes can present a greater and/or additional* threat.

* Edit to reinforce that it isn't simply a question of what presents the most risk... it is a question of cumulative risk.

[divvy]

136. ionizing radiation

Ionizing radiation (the same particles with the same energy) does have the same effect regardless of the source. You are introducing a different subject -- the human body's storage of particular elements. Of course, strontium is stored in bones and iodine in the thyroid, which makes them more dangerous.

Just to give yet another example, naturally occurring radon gas is the second most frequent cause of lung cancer, after cigarette smoking, causing 21,000 lung cancer deaths per year in the U.S. But how many people care about it?



I am not defending radiation releases as unimportant, but I do believe most of what I have read about it in the press is fairly meaningless, and the reactions I've heard to press snippets have been generally exaggerated and unreasonable.

Certainly, nobody who smokes has any right to mention radiation exposure.

Incidentally, radon is a pollutant emitted by geothermal power stations. Oops, there goes "green" energy!

[divvy]

145. radiation fixation

I think the comments here about the so-called fixation on radiation also ignore the fact that many of us are exposed to other hazardous substances in our environment on a repeated basis. The exposure to multiple chemical, radiological, et. al. subtances over time is cummulative. It seems prudent to err on the side of caution rather than to wait for cancer for autoimmune disease to develop before taking action.

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146. Bindleflot

That's all well and good, but logic remains logic, unless you are determined to throw it out the window. To take a made up example, suppose bindleflot is a known poison and there is an accidental release from the dog biscuit factory on the outskirts of town. You're right to be concerned, but if the amount of bindleflot concentration in the town water supply is 1/1000 of the naturally-occurring bindleflot concentration in the orange juice you drink every morningdoes it really make sense to panic and start buying bottled water, while you keep on drinking orange juice?

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147. alpha-emitters are ingestion hazard

In a closed thermodynamic cycle, heat must be rejected; that's a fact. You need a sea or a river. Air-cooling towers can augment heat rejection, but I don't think they can support a fully closed system.

(Some cooling must be done with water.)

It won't matter if the water is contaminated by beta- or gamma-emitting radionucleides. They penetrate the body easily. Only alpha-emitters are an ingestion hazard. (And a very nasty one, too. Try Googling "lead bismuth cooled reactors" and "polonium-210". The Russians messed around with these on their submarines and suffered fatalities.)

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148. I disagree

To (hopefully) add a bit more to the subject... such a scenario would involve not only "zero and close range external exposure to the source of emitted particles" and a potential ingestion risk, it would also involve the risk of the radionuclides being absorbed into the body through the skin and/or via orifices/membranes and open wounds. I think the risk from purely external exposure to alpha emitters is usually classified as "very low" to "neglible" based on there *usually* being adequate layers of dead skin to block the particles. When you add to that the "aborbed into the body risk" mentioned above... possibly also inhalation exposure to an alpha emitter like radon... it may (would need to be researched) be the case that even alpha emitters in said "bathing" water might be of significant concern.

It isn't correct to say that only alpha emitters are an ingestion hazard... they all are. Even if you were bathing in water containing alpha, beta, and gamma emitters I think ingesting any one of them would increase your risk in complicated ways depending on exactly which radionuclides are involved. However, I take it what was meant is that you'll have the external risk from beta and gamma emitters no matter what while the alpha emitters will become a (and possibly the) major threat when you ingest them.

[divvy]

149. correction

I meant to say "alpha emitters are only an ingestion hazard" instead of "only alpha emitters are an ingestion hazard". Alpha particles can be stopped by a sheet of paper. But ingested they can be deadly. That's how the Russian's got Alexander Litvinenko - they used polonium-210. Gram for gram, it's 250,000 times as poisonous as hydrogen cyanide.

It's also present in tobacco.

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150. the dangers must be prioritized

One must prioritize. Given ten dangers, all of them dangerous, if you order them from #1 to #10 according to the level of their danger, which end do you worry about first? If you can mitigate all ten, great. It is rational to worry about only those you can do something about. But it is not rational to worry about lesser ones that you cannot do anything about (or are very expensive to mitigate) while ignoring greater ones that you can mitigate more easily or at less expense. It is also irrational to worry about dangers which are below the level of other dangers that are considered statistically benign and whose existence in our lives we have accepted (such as eating bananas or sleeping in the same bed with another person).

I also reiterate that nobody has recognized the importance of half life of the isotopes being mentioned.

Without proper context (which involves prioritization) I find much of the discussion about radiation to be sophistry.

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142. First pictures emerge of the Fukushima Fifty

First pictures emerge of the Fukushima Fifty as they battle radiation poisoning to save Japan's stricken nuclear power plant

http://www.dailymail.co.uk/news/article-1369216/Fukushima-Fifty-First-pictures-emerge-inside-Japans-stricken-nuclear-power-plant.html

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143. Gate Seals

“When the gates are closed, they are made watertight by an inflatable seal, similar to a bicycle innertube, that runs around the sides and bottom of the gates. Electric air pumps are used to inflate these seals and keep them inflated as air leaks out of them over time.”

“These pumps are powered by electricity from the power grid, and not by backup diesel power or batteries. So once the power grid in Japan was knocked out, these seals could not be inflated if they lost air over time. If these seals lost air they could lead to significant water loss from the pool, even if there were no direct physical damage to the pool from the earthquake or tsunami. This may be what happened at pool 4, and could affect the other pools as well.”


http://allthingsnuclear.org/post/3964225685/possible-source-of-leaks-at-spent-fuel-pools-at

Note: I found the above link while reading this thread on DU.
http://www.democraticunderground.com/discuss/duboard.php?az=show_mesg&forum=439&topic_id=702812&mesg_id=715343

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144. Thanks, I hadn't thought about the gate seals

Thanks, I hadn't really thought about the gate seals. What concerns me is not so much leakage from the pool per se... I agree it is a problem and I understand that there are multiple leak pathes, including ones in your excellent reference. What I was saying is - there were reports that the power had been hooked up and parts ordered to restore the core cooling pumps... What parts? Switchgear breakers? I suspect that these pumps are inaccessible due to the radiation... some may be under water... some may be in enclosed rooms that are under water. Some of the water being sprayed onto the site may have dripped on switchgear in the plant or hydrogen explosions may have destroyed that switchgear. The report that bothered me was that we plugged in the power, there were some problems, and we ordered parts. Really??? That was fast! Can't believe it...

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151. New nuclear strategies

I'd be interested in a new discussion focused on strategies to make nuclear energy a trusted, safe source of electricity going forwards.

It would be interesting to better understand both the new thrid generation technology and the approaches used by various countries to safely manage their nuclear power plants.
It seems to me that the Japanese model - involving private utilities like Tepco - might not be the best approach. This reminds me of the Thatcher's privitation of the UK's railway system - which was a safety disaster.

I note that the Germans have temporarity mothballed eight of their oldest nuclear plants, including the one located on the Rhine in Biblis - near xxxx’s home in Heidelberg. I have not researched the Germans' approach to nuclear power management.

There's a useful presentation of the French approach http://www.world-nuclear.org/info/inf40.html

[divvy]

152. mothballed plants and policy

Germany Set to Abandon Nuclear Power for Good
by Juergen Baetz
March 23, 2011

BERLIN -- Germany is determined to show the world how abandoning nuclear energy can be done.

The world's fourth-largest economy stands alone among leading industrialized nations in its decision to stop using nuclear energy because of its inherent risks. It is betting billions on expanding the use of renewable energy to meet power demands instead.

The transition was supposed to happen slowly over the next 25 years, but is now being accelerated in the wake of Japan's Fukushima Dai-ichi nuclear plant disaster, which Chancellor Angela Merkel has called a "catastrophe of apocalyptic dimensions."

Berlin's decision to take seven of its 17 reactors offline for three months for new safety checks has provided a glimpse into how Germany might wean itself from getting nearly a quarter of its power from atomic energy to none.

Read the full article at:

http://www.commondreams.org/headline/2011/03/23-7

DU discussion thread here:
http://www.democraticunderground.com/discuss/duboard.php?az=show_mesg&forum=439&topic_id=729003&mesg_id=729003

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153. Not all Germans agree

There's a good pro-nuclear interview with Australia's Barry Brook HERE:

http://www.faz.net/s/Rub469C43057F8C437CACC2DE9ED41B7950/Doc~EE253BFEB3C6D4B96905E3516D0C29D78~ATpl~Ecommon~Scontent.html (in German)

He believes that when we compare nuclear energy to all other options, it's the safest and most environmentally sound strategy to follow. By contrast, he thinks that coal-fired power plants are a huge problem.

He points out that Japan just witnessed a refinery explosion with dozens of deaths ...

Mich wundert, dass immer nur über abstrakte Risiken und unbekannte Wirkungen gegrübelt wird. Dabei ist in Japan soeben ganz konkret eine große Öl-Raffinerie explodiert. Dabei sind Dutzende Menschen gestorben und über den umliegenden Gebiete hängt eine Wolke aus giftigen Gasen. Diese Wolke hat die Gesundheit der Bewohner unvergleichlich mehr geschädigt als alle Strahlenfolgen.

... and that the resulting health impact has been far greater than that of the reactor problems. But, no one talks about that.

[divvy]

155. probably not the best time

I don't think this is probably the best time to have a debate on the merits of nuclear power. Emotions are high... and I don't blame anyone who is anti-nuke at a time like this. I do think that if China keeps popping up new nuke plants and we just drill nat gas like crazy... they will have a much better power situation than we have in the long term. One big reason they are able to do it, though, is that it is a lot cheaper to build things in China than in the US. The main reason why plants haven't been built here is that they are so expensive... and that is too much risk in the absence of regulation guaranteeing a return on the investment. The Chinese government owns the land and the utility companies in China... and they turn out a lot of engineers from their schools. FYI - Palo Verde (in Arizona) is the only nuclear plant in the world not located near a body of water, so it can be done. Palo Alto uses the waste water from 3 cities as part of its cooling system. It takes some creative design, but it is possible to put a nuke plant in a desert. A lot of its power goes to California. Some plants are on small rivers and augment it with big lakes. Hard to make lakes in the desert, though

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162. trechant

I thought this comment was particularly trenchant:

Wie bewerten Sie die Medienberichte über Japan?

Sie sind sehr unausgewogen. Über Fukushima gibt es minütlich Meldungen. Dagegen fallen die Berichte über die Tragödie, die das Erdbeben angerichtet hat - bald 20.000 Tote, Millionen Menschen ohne Obdach, verzweifelte Familien, zerstörte Infrastruktur – völlig ab. Ich frage mich, ob das den Japanern nicht zynisch vorkommt.

English translation via Babelfish:

How do you evaluate the media reports over Japan? They are very unbalanced. Over Fukushima there are minütlich messages. On the other hand the reports fall over the tragedy, those the earthquake arranged - soon infrastructure destroyed 20,000 dead ones, millions humans without shelter, desperate families, - completely off. I ask myself whether that does not seem to the Japanese cynical.

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163. tsunami damage

You raise a good point, ... there is lots of concern about the nuke plants (because they are the unknown and poorly understood)... but the loss of life and so many homes and whole towns destroyed by the tsunami. There really wasn't a lot of earthquake damage considering how bad it was. The Japanese had tsunami warning systems and mitigation structures. Maybe they weren't enough, but they were more than any other country has and it saved some lives. I am happy to hear that many countries are trying to help. The US Navy and their families at the bases have helped where they could. This is America at its best... I know the Japanese culture is one of self-reliance, but there is no dishonor in asking for help in times like this. I wish their people many better days ahead... I can only imagine how Japanese Americans feel seeing the homeland of their ancestors experience such distruction.

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154. DU thread .... Common objections to Alternative energy

Common Objections to Alternative Energy Generation Systems discussion on DU here:

http://www.democraticunderground.com/discuss/duboard.php?az=view_all&address=439x731237

This could become a very gratifying thread. thx mineralman

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190. new strategy? we must all die first

WE MUST ALL DIE FIRST.

Yes, that would be my assessment of when the USA will get to Nuclear Power, big time.

For you see, both parties/camps are correct here. One group who has been associated/trained in nuclear power and safety; another that grew up with Three Mile Island and the fears attendant with that.

Those fears are real, regardless of the facts and statistics. It is like many Americans fear flying in airplanes, yet freely drive in automobiles, even as passengers. Facts clearly show cars are far more dangerous. But the moment that plane leaves the ground, white knuckles abound.

Thus, Three Mile Island happened to coincide with the scary movie--China Syndrome, the advent of more widespread Television coverage, and the shift in Americans to highly doubting both governments and industry. This "perfect storm" created a couple generations of truly frightened citizens. All commercial building nuclear activity in USA stopped.

But silently, other countries of the world have grasped the economic potential of nuclear power...to become economic leaders above the USA, and are fast building power plants. Even the Arabs, who sit on tons of oil, are building nuclear reactors.

Will this continue after Japan?

Some surveys taken in the USA the past few days surprised me...about half the USA people seem to state they would live within 50 miles of a Nuclear Reactor. Hmmm.

Even with optimistic price projections for oil/gas and other energy forms, prices will rise from here. Young people simply want their computers, lights, homes heated, etc. they will demand electricity. Period. And if an improving economy is part of the bargain with Nuclear Power, then it may slow the economic decline of the USA, and be a key factor.

Elders like me sit around the lunch table asking how long will Americans send their vast wealth abroad to foreigners, purchasing oil/gasoline. Huge sums lost...inheritances being wasted. Yes, the current generation can live for awhile on accumulated inheritances. But that will soon be gone.

One real plus for nuclear power is that all the jobs, from uranium digging, processing, building reactors, running them...disposal, can all be done at home. All money kept here. People having useful jobs.

So I suspect the time will come...when the current generations are not here, that the now very young folks will go towards nuclear power. (same for Marijuana--that I never tried).

Two things could speed up the process.

The first is the oversight structure for running nuclear reactors. In the Navy, this was done by a marriage of Navy personnel, private contractors such as GE, and a Super Governmental oversight group run first by an Admiral Hyman Rickover. As a Quality Assurance manager at GE, I wore two hats...one policing and reporting to GE. Another reporting straight to the Admiral. If I felt there was any wayward discretion, I could put either hat on...or both. We could stop a submarine dead in the water...and fix it. An oversight model that the public could trust would be a good step.

Second, an inherent problem with current nuclear reactors is they bring so much stored energy to risk all at once. They are large. So an accident can have huge potential consequences.

Visualize the old steam engines on railroads. The engineer shoveled in a few shovels full of coal at a time, into a steam boiler. The second car on the train was filled with coal (not burning). So at any one time, only a small amount of this coal/steam was at risk. If the stream engine blew up, it didn't destroy the town. This is called a CONTINUOUS FEED PROCESS. Here, you keep adding shovels of coal, burning it up fast, removing used coal, and adding more in. People used coal in their houses this way, also.

So why not continuous feed for nuclear power power? That is, designing the plants to be much smaller, continuously feeding in a core of much less quantity of uranium, burn it up quickly, then eject it out the backside, bringing in new fuel. Then, if an accident happens, much less total energy at risk. Like a small dam breaking, versus a large one.

Americans may get more comfortable with that type of arrangement.

Time will tell...some things to ponder.

Perhaps more, later, on this subject.

[divvy]

191. to build more now is insane

"all the jobs, from uranium digging, processing, building reactors, running them...disposal, can all be done at home. All money kept here."

Do you know anyone who has (or even wants) a job in nuclear fuel disposal? I don't.

That's the real problem. In addition to the titanic capital cost of building nuclear plants, the environmental damage of mining, and all the dangers involved with handling radioactive material, there's still no agreed-upon solution for where to put the spent fuel.

This is the reason there was so much spent fuel stored on site at Fukushima: they didn't have any better place to take it. That's a bit of a problem, now that the "temporary" storage pools, filled to well over their designed capacity, can't be cooled properly.

I understand that every commercial reactor in the US has the same storage arrangement, i.e. long-term over-reliance on a facility designed to be short-term.

It was not very smart to build all the reactors without an "exit strategy" for the fuel. To build more now that we've seen the consequences would be insane.

[divvy]

193. in the words of Albert Einstein ......

Words of one famous physicist - Albert Einstein

"Nuclear power is one hell of a way to boil water."

"I know not with what weapons World War III will be fought, but World War IV will be fought with sticks and stones".

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194. thousands do ...

Thousands do work in nuclear disposal today as I write. The more critical points are removal from the reactor into the pools on-site, where the radiation then decays and the fuel cools off. You don't hear of many people getting radiation poisoning, do you? Believe me, it would be in the press and on TV.

We recently had TV reporters stand over this pool of spent fuel. The readings for radioactivity were less that outside background levels. I, too, have stood over these pools.

Now, after some time there, these spent fuel rods/assemblies are put into containers, and large CASKS...for eventual burial. These steel containers are welded shut, and surrounded by thick cement/rebars. A few days ago at the Port Saint Lucie Nuclear Plant I viewed the testing film/videos of such a cask being on a truck running into walls at 60 mph...no damage; on trains running into a test cement wall at 60 mph...no damage; and so on.
But since there is no where to send them, these casks now sit in a separate vault, awaiting eventual shipment. You can walk around the vault with instrumentation and see no radioactivity.

But here's the deal...this is one of the most unknown/fearful things about this stuff. Even if the train wreck opens the casks, then opens the containers, as long as people stay back away from it, it is not very dangerous. In short, aged spent fuel is a low risk item from a catastrophe standpoint.

Similarly, hospital workers work daily around radiation, and irradiated low-level waste, that is shipped by tons around for disposal. They don't seem fearful...and they are not dying more than the population rates.

So for the younger generation,,very young, it is a combination of the educational aspect,,,that radiation exists in nature...a lot, and the handling aspects, that one can (and does) have his/her very own instrumentation to measure the radiation in the vicinity/area one is in; and proper rad-con measures require surveys by suited teams to first measure anything detectable before workers can even enter.

Yes, it is eerie to go from inside a reactor, out into the sunshine, and have your own personal dosimeter reading go up!!!

The young will figure this stuff out.

[divvy]

195. you make some good points

You make good points. Xxxxxxx I suspect that spent fuel waste disposal will become a big issue now. I wish it hadn't taken this disaster to get it recognized as an important issue to resolve. Nobody seems to want it in their state. The most important issue for nuclear power is not waste disposal, though. It is cost to build new capacity. It is just way too costly to field fabricate these plants. We need designs that are smaller, as you suggested... and modular where you can just add factory built capacity as you need it... and it needs to be safer designs, like xxxx has spoken of. Unfortunately, that hasn't been where the industry has been going. Power uprating 40 year plants so they can be run even harder is not the safe, conservative choice. I have kind of stayed away from the health hazard debate, because that is not something I know a lot about. I have been saying for a long time on this forum that imported oil is what we can't afford any more. I like T Boone Pickens proposal to replace diesel fuel in trucks with nat gas. I would love to have stations for nat gas at truck stops... I would burn it in my car. This alone would take a big bite out of the need to import oil. All new electrical capacity should be nuclear or renewable. These choices would make the country more self-reliant and be eco friendly will greatly less global warming emissions. It isn't cheaper, but it is better and self-sustainable. The cheapest solution is not always he best answer, because the cost of polluting the environment is not factored in. It may be hard to think about nuclear as being clean after this disaster, but coal has killed many people mining it, breathing the polluted air, etc That cost and the cost of global warming is not priced into the marketplace. Sure, nat gas is cheap (now), but if you generate another 20% of our electricity with nat gas, it won't be cheap then... then what will you do? Import it as liquid nat gas? That's no solution... just more of the same.

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203. nice piece on diminuitive reactors here

Bloomberg has a nice piece on diminutive reactors

http://www.bloomberg.com/news/2011-03-22/meltdown-or-not-future-for-nuclear-seen-in-diminutive-reactors.html

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156. attn DU nukes: NRC seeks design comments

NRC seeks comments on the new GE/Hitachi 1,600 MW BWR Design for US

http://www.reuters.com/article/2011/03/24/us-utilities-ge-newnuclearreactor-idUSTRE72N52320110324?feedType=RSS&feedName=GCA-GreenBusiness&rpc=43

[divvy]

157. 128 Fukushima 50 photo's

128bPhotos of Fukushima heroes at work http://news.yahoo.com/nphotos/Japan-Fukushima-Nuclear-Plant/ss/events/wl/031411fukushima

[divvy]

158. little protection for radiation exposure

There is little protection for radiation. Protective clothing is really only intended to prevent the spread of contamination, taking material from a high rad area to a low rad area. The only way to shield from most of this radiation is many inches of lead. I am sure that they are wearing full face air filter masks or Scott Air Packs to prevent breathing in particulate contamination. It is my understanding that all of the site heroes are volunteers from the plant and military. They have volunteered to try to save their country. It was in danger if nobody stepped forward. I think that they are doing everything they can to prevent dangerous over exposures... at least some of the workers have received dangerous overdoses due to sudden increases in radiation levels. The most recent stepped in some very radioactive liquid and was immediately sent to a hospital. They have also rotated in replacements... the original 50 has probably grown to 3x that, or more. Most of these workers have or will probably receive their lifetime radiation exposure... some may have radiation sickness... I doubt if any die directly from their exposure, though they will be at increased risk of getting cancer. I have no doubt -- if nobody responded to this accident, much of Japan would have had to be evacuated and the public would be exposed to a lot more radiation. I have been frustrated at not seeing more external support for the accident response, but maybe it is there and it just hasn't been reported. These guys and maybe some gals onsite are heroes and they are risking their lives... no question in my mind. They won't intentionally give anyone a lethal dose, but the situation is not stable and they know that a lethal exposure could happen at any time. We are fortunate that there are so many people willing to step forward and try to save their country. They are at war with a disaster that will show them no mercy. Walking away was never an option.

[jpak]

159. But I thought everything was under control?

Silly me

[divvy]

160. self delete

.

[divvy]

161. detection ability

Radioactive material from the plant will be detected all over the world. That is as much a tribute to our ability to detect very small amounts of radiation as anything. Detecting it is not the same as recording radiation levels that are hazardous. Bomb testing was detectable all over the world, even in the ice in antarctica. Chernobyl most surely was. The further away you are, the more diluted is the radioactive material. The reason they say that they can detect it is not meaning that radiation levels have increased significantly... it only means that they can detect the specific radioisotopes given off from the plant, which are different than background natural radiation. There is natural radiation around you right now... or taking an airplane flight... that will give you more exposure than this accident will... unless you are in Asia and near Japan

[divvy]

164. partial tour

I just returned from a partial tour of the xxxxx Nuclear Reactor.

I verified that the pools of the spent fuel from cores/fuel assemblies removed during refueling ARE UNDER THE CONTAINMENT BUILDING...unlike Japan. This containment is about 3 feet thick concrete with many steel rebars, about 1.5 inches in diameter bars. The bottom floor of the reactor containment was a minimum 10 foot concrete pour.

I didn't get irradiated...

[divvy]

165. Good information links

Found a good source of up to date information: http://bravenewclimate.com/

Also on radiation: http://www.phyast.pitt.edu/~blc/book/chapter5.html

Nice graphic here: Ten Days at the Fukushima Plant

[LAGC]

166. According to your chart...

It looks as if things are slowly coming under control.

So why are you kicking this old thread? It's outdated news.

[divvy]

167. potential severe nuclear breach/meltdown

Radiation leak may be from #3 core http://english.kyodonews.jp/news/2011/03/81048.html

Natural disaster exemption may not apply to Tepco http://english.kyodonews.jp/news/2011/03/81077.html

Japan PM doesn't know when the Fukushima nuclear crisis may end http://english.kyodonews.jp/news/2011/03/81073.html

[divvy]

168. understanding highly radiated water

It would help a lot in understanding the implications of this high rad water, if we knew where they were when thet encountered it. It is hard for me to comment. The fear is that means a breach from the reactor vessel or fuel pool. I think that it could, but it might not. There are other ways that you could get reactor coolant into the reactor building. For example, a coolant sample line could have broken... There are lots of things that could cause it. The primary containment isolation valves don't have power... technically, primary containment doesn't exist. Secondary containment has deen destroyed (that is those buildings that have collapsed or have holes in them. I am shocked that a worker would ignore a high rad alarm and stand in a puddle of water. That is pretty incredible under the circumstances. These workers are in grave danger... it is no time to forget their training. Maybe they are tired and totally stressed out, but that isn't good... Now, they are widening the evacuation area and telling people that they can voluntarily evacuate fourth to find better conditions. Good idea! The situation isn't under control. I am surprised that the fire trucks are still pumping salt water... why not tap water? I wish we got more info on the status of systems and the damage they see. There are robots on the way from the US. This should allow more exploration of the plant. The radiation levels are too dangerous to send people out with cameras. I seriously doubt that core cooling will be restored by just getting AC power... at least not for all 6 units. Engineers should be designing new equipment that could be "hooked up" to perform those functions of core and fuel pool cooling. If they are not needed, fine... but get started now. The real danger in my mind is that the rate we are seeing progress is in a race with the situation deteriorating. If just one of those plants goes "south", then dose rates could prevent work on all six plants. Then they all go "sourh."

Somebody pressed me early in this thread for what is the worst case scenario. After some thought, I said that all of Japan could become uninhabitable... no more Japan. (see post #51) Now that is, I hope, worst case... and I would say the odds of that are low, but not very small. This is gravely serious and it is nowhere near under control. Yes, there has been some progress, but the situation has not been stabilized. It is only the heroes with "fingers in the dike" that are preventing a disaster... hopefully, somebody is trying to build some replacement systems for those plants. I know it is a big job, but waiting to find out the bad news doesn't change the outcome.

[divvy]

169. sounds like reactor 3

It *sounds* as though two workers were sent under Reactor 3... a previous survey of the area had not revealed a radioactive water threat and these workers were sent in with less than adequate leg/foot protection for what they encountered... they encountered a radioactive puddle... their dosimeter alarms went off but they ignored it and forged ahead... they stepped or stood in the puddle and received radiation burns... subsequent analysis of the puddle water revealed contamination which Japan's Nuclear and Industrial Safety Agency thinks is consistent with a leak from the core.

A report on the water.

http://www.tepco.co.jp/en/press/corp-com/release/11032503-e.html

[divvy]

175. DU thread here:

http://www.democraticunderground.com/discuss/duboard.php?az=show_mesg&forum=439&topic_id=737727&mesg_id=737727

a second related DU thread here:

http://www.democraticunderground.com/discuss/duboard.php?az=show_mesg&forum=439&topic_id=735316&mesg_id=735316

[divvy]

170. Is TEPCO the walking dead?

the "exemption" link was news to me. Seems like the exemption was intended for circumstances like this, so I don't understand the government's claim. I would be shocked if Tepco survives as a company. Their safety record was very spotty anyway. I was shocked to read a couple days ago that banks were loaning Tepco a bunch of money. You gotta be kidding? Maybe I just don't understand Japanese law? Maybe? I don't know anything about Japanese law, but Tepco would be the walking dead in the US.

[divvy]

171. natural disaster exemption link (and others)

Radiation leak may be from #3 core http://english.kyodonews.jp/news/2011/03/81048.html

Natural disaster exemption may not apply to Tepco http://english.kyodonews.jp/news/2011/03/81077.html

Japan PM doesn't know when the Fukushima nuclear crisis may end http://english.kyodonews.jp/news/2011/03/81073.html

[divvy]

172. more links

Injured workers were knee deep in contaminated water

http://english.kyodonews.jp/news/2011/03/81122.html

Fresh water injections into #1, 2, 3 http://english.kyodonews.jp/news/2011/03/81116.html

[divvy]

174. no free political pass

this is contrary to what I have been reading so far too. May be, as more evidence of TEPCO's carelessness/negligence comes to light, it would be hard to give it a free pass politically.

[divvy]

173. what are the options

Perhaps Tepco is toast but what are they going to do... pull them off the job right now? Would anyone want to assume responsibility for that call (imagine if things then got worse) and would any company want to take over for Tepco right now? Perhaps creating as much money as Tepco needs to keep plugging away at the problem is the only real option?

[divvy]

176. media account of the explosions

Some views on the explosions:

http://www.nytimes.com/cwire/2011/03/25/25climatewire-us-experts-blame-fukushima-1-explosions-and-19903.html?pagewanted=print

Interesting bit about removal of unit 2 wall panel

[divvy]

177. Mark I is metal containment

The article almost lost me when it talked of concrete primary containment - False... Mark I is metal containment... but the main thrust of article is correct. SBGTS (ventilation for venting) would have been inoperable due to loss of power. Venting hydrogen through the system could ave caused explosion in the Reactor Buildng. Somebody asked about a Hardened Vent System... we retrofitted such a system where I worked that would have allowed venting directly to the stack w/o AC power and the ventilation system. I don't know if it was installed on Japan. Glad they have stopped dumping salt into the reactor on 3 units. Nobody knows what all that salt will do to the reactors and fuel pools.

[divvy]

181. U.S. Navy brings fresh water

By ERIC TALMADGE and MARI YAMAGUCHI, Associated Press Eric Talmadge And Mari Yamaguchi, Associated Press – 26 mins ago

SENDAI, Japan – Japan's government revealed a series of missteps by the operator of a radiation-leaking nuclear plant on Saturday, including sending workers in without protective footwear in its faltering efforts to control a monumental crisis. The U.S. Navy, meanwhile, rushed to deliver fresh water to replace corrosive salt water now being used in a desperate bid to cool the plant's overheated reactors.

<snip>

Officials have been using seawater to try to cool the plant, but fears are growing that the corrosive salt in the water could further damage the machinery inside the reactor units.

TEPCO is now rushing to inject the reactors with fresh water instead, and to begin extracting the radioactive water, Nishiyama said.

Defense Minister Yoshimi Kitazawa said late Friday that the U.S. government had made "an extremely urgent" request to switch to fresh water. He said the U.S. military was sending water to nearby Onahama Bay and that water injections could begin in the next few days.

The U.S. 7th Fleet confirmed that barges loaded with 500,000 gallons of fresh water supplies were on their way.

full story here: http://news.yahoo.com/s/ap/as_japan_earthquake

[divvy]

178. More DU threads

There is an on the ground report here

http://www.democraticunderground.com/discuss/duboard.php?az=show_mesg&forum=439&topic_id=740054&mesg_id=740054

another popular thread is here

http://www.democraticunderground.com/discuss/duboard.php?az=show_mesg&forum=439&topic_id=740054&mesg_id=740054

[divvy]

179. outcomes

Earlier, someone brought up the subject of outcomes. (also see posts #51 and #52) That of course depends on how things go with the reactors and how much additional contamination is released into the environment. However, there is already one thing that will be obvious to some but not necessarily all...

Contamination in excess of Japanese limits has been detected in the air, on land, in water sources, near the shoreline, and even further out to sea. Japan is going to have to engage in a rather massive contamination reconstruction effort. It will have to go back over all of the data that has already been collected and it will have to collect a huge amount of additional samples/measurements in order to zero in on exactly how much was released and where plus how much remains and where. Although progress and decisions will be made along the way, this effort may take years to complete and there will continue to be studies done on the subject for decades to come.

Due to short-lived radionuclide decay, contamination being rained/washed away and deeper into the soil, etc some radioactivity levels and threats will decrease in a significantly rapid way. However, other threats for example from longer-lived radionuclides will remain... somewhere... for a long time. So once further contamination is stopped there should be two stories developing in parallel... 1) the significantly rapid decline of some levels/threats and 2) the more thorough assessment of contamination and particularly the lasting threats that will have to be dealt with in some way.

As for keeping an eye on #2, I've started to filter the news looking for "Japan AND Cesium". One recent hit is this:

http://news.sciencemag.org/scienceinsider/2011/03/japan-soil-measurements-surprisingly.html

which includes a pointer to one site that has begun to publish some sampling reports :

http://www.mext.go.jp/english/radioactivity_level/detail/1304099.htm

Edit: Here is a better MEXT starting link from which you can dig down...

http://www.mext.go.jp/english/radioactivity_level/index.htm

I think this is the type of information one needs to keep an eye on. Hopefully it will be adequately covered and summarized so that those interested can follow developments and get a sense for what may be declared uninhabitable and/or unfit for agriculture/grazing... what may be disregarded or remediated... etc.

[divvy]

180. reports of a big crack in the reactor vessel

There are pretty scary reports of a big crack in the side of the reactor vessel. I am having trouble believing that, because there is no way that anyone has been inside one of the drywell containments to see the vessel. The radiation level is too high. Besides, even if you are inside the drywell with a robot or camera, there is a foot of stainless steel mirror insulation, or the equivalent, on the outside of the vessel that would have to be removed to see the vessel wall. If someone has seen a big crack in a steel structure (they thought was the RX vessel), it was probably the drywell containment. The implications of a cracked containment are far less onerous than a cracked vessel. These reports have to be wrong... I am 99% sure... if the reason they give is a visual sighting. Any large crack would tend to equalize the RX and drywell pressure... if they know what they are.

[divvy]

182. Rachael Maddow / Times report

Maddow reported this last night, saying it was reported by the Times based on a not-for-attribution eyewitness. I couldn't find any other reference to it this morning.

[divvy]

183. It wasn't the side of the RX vessel ....

I believe somebody said it, and I heard her report to... what I am saying is that whatever they saw, it wasn't the side of the RX vessel. It wouldn't surprise me at all if there isn't a drywell split open from a hydrogen explosion. Those drywalls are about 5/8" of carbon steel rated for about 65psig. A RX vessel is about 6" thick stainless steel rated for about 1350 psig (or so). Big difference! ... and a big difference in what it means for containing a melted core. I don't know where that very radioactive water came from. I think it could have spilled from the pool overhead. Concern about a breeched vessel was all the news Friday. Maybe it has breeched, but I haven't heard a good reason why they think that, at least not yet.

[divvy]

184. more about a breeched vessel

About a breeched vessel -- the inside of the reactor has a structure called the RX shroud. It surrounds the core. It is intended to allow 2/3 core coverage in the case of a design basis break of the recirculation pipe. Even if a vessel was breeched in the side wall, the core shroud would allow keeping water in the vessel and covering enough of he core to cool it. An breech of the vessel would be very bad news, but it would not necessarily mean that a complete meltdown is inevitable.

[divvy]

185. 10-million times normal

Source: NHK

Tokyo Electric Power Company says it has detected radioactive materials 10-million-times normal levels in water at the No.2 reactor complex of the Fukushima Daiichi nuclear plant.

<snip>

University of Tokyo graduate school professor Naoto Sekimura says the leak may come from the suppression chamber of the Number 2 reactor, which is known to be damaged

Read more: http://www3.nhk.or.jp/daily/english/27_12.html

This is worrysome.

[divvy]

186. highly radioactive water is not suprising

The fact that there is highly radioactive water at the site is not really very surprising. There are fuel failures in all the cores... some, if not all, have major melting and loss of geometry. There has probaby been major clad damage to the spent fuel in the pool, possibly causing some fuel clad to burst releasing radioactive gasses and perhaps some solid fuel pellets. There has been direct reactor venting to the reactor building. The containment (which includes the suppression pool) overheated from relief and safety valve operation (and possibly HPCI turbine operation).... experienced hydrogen explosions in the containment and what used to be the reactor building. Water hoses have been splashing water in (and probably over the sides) of the pool spilling very radioactive water from the pool. There has to be water accumulating in the reactor building basement. A major breech of the suppression pool or drywell is likely at some plants, but without any AC power, primary containment was lost at all plants. I am not sure how so much radioactove material is leaking into the ocean nearby. Some is condensation of air releases... some is just runoff... it sounds like there might be an ongoing liquid release through their radwaste system, though. I would hope that somebody is looking at their radwaste discharge path to see if it is prudent to close a manual isolation valve somewhere. Most of the radwaste treatment system is non-seismically qualified... and has no power... and no battery backup. An ongoing liquid release of radioactive radwaste is very possible. Also, in general, the longer this goes on in an uncontrolled fashion, the larger the uncontrolled release... and the more survey teams will find. I wouldn't read a lot into the discovery of high rad levels in the area of the plant... it just confirms the harm in what we already know. This is a disaster that we don't yet have under control and will take many years to clean up... the job is way beyond anything else in the nuclear area that has ever been attempted, except maybe the 2 A-bombs in WWII...

[divvy]

187. earlier reports of high radiation at #2 are wrong

This morning reports are saying that the earlier reports of very high radiation at #2 are wrong (Yahoo) or partially wrong (Kyodo News). Tepco seems to say that the first readings were not credible and workers will repeat them.

This is no way to run a railroad (or a nuclear facility).

http://news.yahoo.com/s/ap/ap_on_bi_ge/as_japan_earthquake

From KYODO NEWS (it still carries all of the old scary headlines/advisories):

22:25 27 March Woes deepen over radioactive water at nuke plant, sea contamination http://english.kyodonews.jp/news/2011/03/81345.html

20:45 27 March
NEWS ADVISORY: TEPCO says radioactivity data of No. 2 reactor puddle partly erroneous
16:43 27 March NEWS ADVISORY: Gov't orders TEPCO to find cause of radioactive water in No. 2 reactor

[divvy]

189. most recent update on radiation levels

The most recent update on radiation levels:

"...Plant operator Tokyo Electric Power Co. said early Monday the level of radioactive contamination for leaked water from the No. 2 reactor was 100,000 times higher than normal in the reactor's cooling system.

The utility had initially detected the level of contamination at 10 million times higher but later retested the data, citing some errors...."



http://english.kyodonews.jp/news/2011/03/81374.html

[divvy]

188. nuclear tourist ...... thorough info for nuke-novices and experts

this site has been around for many years, and I think it's got a lot of good material on it:

http://www.nucleartourist.com/

[divvy]

192. nuclear fallout in German politics

Why is this man smiling?



His name is Winfried Kretschmann and he's the Baden-Würtemburg Green party candidate. He also probably the next Ministerpresident of the region.
Frau Merkel and her coalition party leader are not amused:



The political change in Germany is a direct result of the Japanese nuclear mess.

[divvy]

196. Kyodo: radioactive water at 2 due to partial meltdown

The government believes highly radioactive water detected at the No. 2 reactor of the Fukushima Daiichi nuclear power plant is due to a partial meltdown of fuel rods there, its top spokesman said Monday.

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

==Kyodo

[jtuck004]

198. "Temporary meltdown". Either there is a translation issue or he

has been reading too much Dale Carnagie.

[divvy]

197. Fukushima aerial video and US radioactive rainwater update

Not that most of us will appreciate what we are looking at, but to look nonetheless...

03/27/2011 Aerial Video of Daiichi

http://www.youtube.com/watch?v=ZKFGavZ_rf4

On a related note, I assume most of you are aware that fallout continues across the US and some rain water (I've seen Washington, California, Maine, and Pennsylvania mentioned but I think we can assume other states too) has been reported to be contaminated above limits set for drinking water. A common reply to this has been a) the limits for drinking water are set based on long term consumption and the rain water levels seen so far are still below the levels that would be "of concern" for short term consumption, b) generally speaking people don't drink rain water, c) although rainwater makes its way into reservoirs etc it gets diluted.

If anyone here *does* drink rainwater and/or provides it in undiluted form to food plants, cows, other food product producing animals... they should be keeping an eye on this. OK... well... I guess everyone should be keeping an eye on the subject.

Edit: I suspect you all know how to perform targeted searchs, but just to provide one starting point:

https://encrypted.google.com/search?num=30&hl=en&lr=&tbs=nws%3A1&q=rainwater+OR+%22rain+water%22+found+OR+detected+Iodine+OR+Cesium+states&aq=f&aqi=m1&aql=&oq=

[divvy]

199. thermal image

I watched the video at your link, and I noticed what looked like steam coming from the side of what I believe is reactor 2. I think it might be reactor two because it still has the roof over it. Also, I was thinking about this thermal image.



The heat dissapation under the roof of reactor 2 looks pretty consistant like it is superheated air. It is not concentrated in one area.

[divvy]

200. every recent picture and video shows that

I think every recent picture and video I've seen has shown "steam" coming out of Reactor 2 building. I can only assume that it is a hot and hot space.

FWIW, I added a link to my previous post... the new vid contains english commentary for the same video. I came across it while looking for an explanation of why the lid was over in the corner. I kept thinking that doesn't look right... the reactor vessel isn't over there is it? Two additional images seemed to confirm that it could be stowed over there during the inspection:

Edit: Another video with English commentary: http://www.youtube.com/watch?v=_6zCkBmt8AY

[divvy]

201. access to Exelon company statements on the crisis indicates ...

I have access to Exelon company statements on the crisis... they have been in contact with Tepco providing accident mitigation advice for awhile... hopefully, early on. The multiple requests for robots is an indication that there is a heightened concern that high radiation levels will make it impossible for humans to stay onsite to fight the battle to save the country from a worse nightmare. Most of the longer term discussion has been about restoring plant shutdown cooling pumps. That may be easier in some of the lesser damaged plants, but may be impossible due to radiation levels in some of the more severely damaged plants. Different, "out-of-the-box" solutions need to be considered. For that, it needs to be an industry-wide effort of the "greatest minds." It won't be easy... and it needs to be done fairly quickly. The status quo is not sustainable over the long term. I think that the reports of high rad puddles are a little misleading as some reports are of 6" or more water on lower levels. I have deen concerned that there is probably flooding of the RX Building lower levels. Apparently, this flooded water is too radioactive to walk in... and now they are trying to figure out a way to pump it out into storage tanks. The contamination of the nearby ocean is surprising to me... the size of it, not that it is happening. Hopefully, somebody s thinking about where an uncontrolled release may be coming from. Tepco, if it has to focus almost entirely on the most pressing of issues, like keeping water in the RX and fuel pools, needs to farm out issues that are very very important but beyond their ability to cope with. We all need Tepco to succeed and I am sure that everyone in the nuclear industry would like to help, if they could.

[divvy]

202. The radioactive core in #2 appears to have melted through its containment vessel

Richard Lahey, who was head of safety research for boiling-water reactors at General Electric when the company installed the units at Fukushima, told the Guardian workers at the site appeared to have "lost the race" to save the reactor, but said there was no danger of a Chernobyl-style catastrophe.

<snip>

At least part of the molten core, which includes melted fuel rods and zirconium alloy cladding, seemed to have sunk through the steel "lower head" of the pressure vessel around reactor two, Lahey said.

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

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

[divvy]

207. The drywell on these units is Carbon Steel

The drywell on these Units is carbon steel with some concrete poured in the bottom of it. If the core melted through the 6+" stainless steel RX vessel, it would make quick work of the drywell. I am told that these Units did not have a "core catcher" installed below the reactor. This is a large casting added in later Mark I plants (my plant had it). If you Google "core catcher nuclear," you will find more about this at Wikipedia. If the core was still in the containment, you wouldn't necessarily have a large uncontrolled release. Since they believe they do from U2, it would seem like the conclusion that the core is through the RX and inside the drywell is wrong. It is probably already through the steel drywell and into the RX building foundation. Under these circumstances, putting water into the vessel is not particularly helpful. It is probably spilling out of the breached drywall and causing the nasty water in the building. To say that this is bad news is kind of a gross understatement. The real danger in my mind is that the total meltdown of even one Unit may make it very difficult to save the other Units, because of crazy high dose and contamination levels onsite. Japan is kind of a long, skinny island. They should consider evacuating the northern part of the country in case it should become impossible to do so later. If there is a plan to get this under control, I don't see it. Today, there was a lot of concern about detecting plutonium at the site. These were small amounts and has more of a psychological impact than a real threat. There is plenty of danger in Japan, but detecting small amounts of plutonium is not high on the list of dangers.

[divvy]

208. WOW

To say that this is bad news is kind of a gross understatement. The real danger in my mind is that the total meltdown of even one Unit may make it very difficult to save the other Units, because of crazy high dose and contamination levels onsite. Japan is kind of a long, skinny island. They should consider evacuating the northern part of the country in case it should become impossible to do so later. If there is a plan to get this under control, I don't see it. --

Wow!

[divvy]

212. they are in the fight of their lives to save their country

Thanks, xxxx. The company I worked for for 25 years before retiring is involved. If something serious happened in the "sweet spot" of what you did for that many years, you would have good insights, too. There are a lot of very professional people working in the industry, and I would hope that they are stepping forward with ideas about how to cope with this problem. For most of those 25 years, I was trained to be an emergency response member for a plant nearly the same as the Japanese plants... so I have an idea what the concerns are in such an accident. In other words, I "speak" the language. There are a lot of people out there that know what I know (and a lot more). It is way too late for this catastrophe to have a "story book" ending, but let's hope the best and brightest are working on mitigating it, because it is far from being over. We don't know how bad it will be. I only wish that this crisis was just one quiz question that needed a great answer. The people responding to this crisis have a 24/7 "test" that will go on for many months and maybe years. Like I said, they are in the fight of their lives to save their country (no quotes around the word - save). We need them to be successful.

[in_cog_ni_to]

204. K & R! I cannot believe this has been completely IGNORED today by

everyone! The most catastrophic even of our lifetime and people are ignoring it???? Doesn't that tell you something? It's much, much, much worse than they want us to know it is.

[kiranon]

205. It's a disaster in slow motion that doesn't make for good TV - nothing

to see - no live action for the camera just invisible radiation rising into the Japanese sky.

[StarsInHerHair]

206. so I have a world map of cesium-137 moving from Japan

http://www.woweather.com/weather/news/fukushima?LANG=us&VAR=niluhemis137&HH=0&LOOP=1

must ennable Javascript for it

[divvy]

214. thanks for the link

Thanks for that link. I am trying to keeping an eye on the various dispersion maps. Since the radionuclides are deposited on the ground and accumulate and remain harmful for varying lenths of time, I would think that someone somewhere is maintaining cumulative deposition type maps... ground concentration type maps. I can't seem to locate anything like that. Have you seen anything like that?

I'm glad you posted that resin link xxxx. I hadn't seen it yet and I've been wondering if they'd do that. I find it interesting that they will be using a UAV. The Soviets sprayed some kind of binding agent around Chernobyl. They also seeded the clouds to encourage contaminants to precipate out. I wonder if Japan could seed the clouds and reduce the threat to other countries.

Resin to be sprayed over Fukushima debries to control radiation http://english.kyodonews.jp/news/2011/03/82074.html

[divvy]

221. some political help may be necessary

(quote from above post)

"Since the radionuclides are deposited on the ground and accumulate and remain harmful for varying lenths of time, I would think that someone somewhere is maintaining cumulative deposition type maps... ground concentration type maps. I can't seem to locate anything like that. Have you seen anything like that?"

Some political help may be necessary to make sure this is being addressed.

edit to fix formatting

[divvy]

209. proposed high-level IAEA conference

FYI...

Amano has proposed that a high-level IAEA conference to discuss the accident should take place at the agency's headquarters in Vienna before the summer. He said that "many countries joined my call for robust follow-up action," since a meeting of the IAEA board of governors on 21 March.

http://www.world-nuclear-news.org/RS-IAEA_chief_proposes_nuclear_safety_meeting-2903114.html

I suspect some here have read quite a bit about Chernobyl and thus will appreciate this.

[divvy]

210. plese repost 212 in GD if it has not been done

thank you

[enum]

211. Japanese Government needs help from other nations

I believe they cannot solve problems by themselves. Japanese
mentality seems not to allow demanding help from outside, but
that is a unique catastrophe. Unlike Tchernobyl we face four
damaged nuclear reactors, four reasons more to accept
international help and rescue activities.

[divvy]

213. more lessons learned

Lessons Learned - The Japanese government is ordering other nuclear plants to make certain upgrades immediately... they,, after all, really can't shutdown all their nuclear plants without huge losses to their economy. The actions ordered are - 1) tsunami protection upgrades to cope with big ones like what they experienced, 2) standby fire truck systems to makeup water to reactor and fuel pools (no kidding, you really missed that one last time), 3) standby power systems to use if all diesels are knocked out. These are all good and well. I would suggest a few others. Erryl's add-ons: 4) Review your emergency response procedures and facilities - a) on-site facilities need to be earthquake and severe weather proof; b) off-site facilities need to be hardened with multiple alternatives, c) multiple evacuation routes should be available and multiple assembly sites; d) communication with all stake holders should be hardened and not vulnerable to loss of power and phone; e) procedures for coping with hydrogen buildup need to be reviewed -- hardened vent system bypassing SBGTS and with highly reliable valving (independent DC and manual operation); f) establishment of off-site emergency response teams for government and utility (industry experts) that are on call for emergencies; g) review all safety systems for common occurrence failures (events that could take out all emergency systems -- and develop coping prcedures and equipment; h) require and provide for permanent off-site storage of spent fuel ; i) require that new nuclear plants fail in a safe mode on total loss of power and w/o human intervention - the technology exists and should be mandated for new plants; j) the safety of life extension of old nuclear plants should be reviewed and replacement with safer designs should be encouraged though a lot more expensive. I am sure there are others

[divvy]

218. US to learn from Japanese Nuclear disaster

US to learn from Japanese nuclear disaster http://english.kyodonews.jp/news/2011/03/82130.html

[divvy]

215. confidental statements from japan implying complete core melt of U2

There are statements coming out of Japan implying that a complete core melt of U2 has probably occurred and it may have breeched the reactor. It is my understanding that these Japanese plants were not built with a core catcher below the reactor. My plant had this large casting below the vessel. You can find out more by Googling "nuclear core catcher" and reading the Wikipedia writeup. Since the drywell on these plants is steel, not concrete... a breech of the reactor vessel will make short work of the drywell. The core is now setting on the Reactor building basement and foundation, if it really breeched the vessel. Pouring water onto it or into the vessel would leech and spill on the site. I am not sure how effective the water is now in cooling the core once it has left the vessel and perhaps they should consider not adding water to U2. It may be doing more harm (in spreading radioactive water) than good (in cooling the core material). The danger now is that dose rates and contamination levels will get so bad that it becomes impossible to maintain the fight to save the other plants. They need to quickly figure out how to do more onsite with less human involvement. It isn't looking good that this disaster is going to be brought under control. The government should be looking at contingency plans for increasing the evacuation zone. I wonder about the remaining population that is north of the nuclear plant site. Can they be cutoff from a good evacuation route? Should vulnerable old people and the sick be moved now?

[divvy]

216. are we closer to this scenario?

On 3/16, xxxx (see post 51) made this interesting comment:

The worst case I see is the fuel overheating and melting its way into the earth. It would contaminate groundwater and air. Once they decide this is inevitable, they should be using drilling equipment equipped with liquid nitrogen to freeze the ground around the meltdown sites (the way they do to construct tunnels in soft soil), combined with lots of concrete, to entomb the site as Chernobyl was. Atmospheric contamination is bad, but will disperse quickly.

What you don't have here is a nuclear explosion like Chernobyl, which spread fission products over thousands of square miles, contaminating crops and livestock. If the cores burn their way down to the center of the earth, so be it. I think our focus then is on ring fencing the underground contamination, using drilling and concrete.

I am far from an expert - that's an opinion for what its worth. I continue to think there are just too many gaps in the information to draw conclusions... even to speculate.

Are recent events bringing us nearer to this type of planned response?

[divvy]

217. can't just abandon a nuclear plant

I wonder how many nuclear plants are offline (all of the I imagine) and running on emergency diesel generators, only. It was never contemplated, I don't think, to run off of these diesels for weeks at a time. I would hope that they are being reconnected to the grid (or the grid repaired) so they can give those diesels a "rest." The last thing Japan needs is another nuclear crisis. There is also a consideration for other nuclear plants that may be in an evacuation zone. If they learned anything, it should be that you can't just walk away from a nuclear plant, even if it is in cold shutdown. It won't stay that way indefinitely. If you were going to "abandon" a plant, there would need to be new systems added to keep essential functions like core cooling and fuel pool cooling/cleanup running... and monitoring cameras. With some modifications, it might be possible to just helicopter operators in periodically to backwash demins or whatever... My point is that you can't really abandon a nuclear plant. If you want to withdraw most or all of the operating crew, you will need to plan for that... and make appropriate modification to do it safely.

[divvy]

220. quick population estimates

Some quick googles and figuring, just for a feel...

1) All of Honshu = over 100 million people

2) Northern part of Honshu, Ibaraki up = over 16.5 million people

3) Fukushima and adjacent prefectures = over 12.5 million people

4) Fukushima alone = over 2 million people

Only a fraction of those numbers would be pregnant women, infants, and children.

[divvy]

227. self delete

self delete <dupe>

[divvy]

228. maybe too early to act, but not too early to plan

Thanks for the population update. How wide is Japan where the plants are? With those kinds of population numbers, it would seem like an evacuation plan would be tough... I imagine there are a lot of people that rely on mass transportation. Politicians, if not trained in nuclear emergency procedures, will, I am afraid, place too much weight on not wanting to create a panic... If action is required, wishing it weren't so won't help. It is unfortunate that a couple of decades of recession has left the Japanese government weak. This Prime Minister has very low popularity with the people and this disaster has surely not helped. He needs to step up and lead his nation... for Japan, it is their 9/11. Mothers with babies and small children, the sick, and old people... they need to be moved to safety first. If I was Japanese, I would move my family to the southern part of the country. The contamination is less there. US citizens not involved in disaster rescue should leave Japan (2 military bases in Japan) or there should be plans to do so.

again, it may be too early to act, but it is almost never too early to plan

[divvy]

241. worlds largest concrete pump heads for Fukushima

http://chronicle.augusta.com/latest-news/2011-03-31/srs...

'The world’s largest concrete pump, deployed at the construction site of the U.S. government’s $4.86 billion mixed oxide fuel plant at Savannah River Site, is being moved to Japan in a series of emergency measures to help stabilize the Fukushima reactors.

from this du thread here: http://www.democraticunderground.com/discuss/duboard.php?az=view_all&address=439x783979

[divvy]

244. can't fill a fuel storage pool with cement .....

Entombing the plant -- there may be some that think the nuclear plants in Japan can somehow be buried in concrete like Chernobyl. These are light water moderated nuclear plants and spent fuel storage pools... it isn't a graphite reactor. You could put a concrete structure around the facility and it would help with shielding and the spread of contamination. It isn't a viable way to store spent fuel, though. The only way I know of to store fuel is under cleaned and cooled water... or dry in specially designed cement casks. You can't just pump cement into the pool or reactors... or at least, I don't think so. Cement could be pumped under the plants to slow core decent into the ground. I see that these cement pumps can also be used to pump water. I don't know what kind of spent fuel storage racks these plants have, but the ones used at our plant required that silica be kept very low. These pools are "off the chart" for silica. With all the salt pumped into the reactor and fuel pool, there is lot's of HCl (hydrochloric acid) in the reactor and pool... acidic water conditions. Cracks propagate faster w/ a lot of chlorides. Even if you build a cement structure around the facility, you need fuel pool cooling and a new water cleanup system for each pool... and perhaps new cranes and support systems to remove the spent fuel for permanent disposal. The fuel in the reactor needs a core cooling system... after a decade or more, it might be possible to remove the fuel from the RX. For the cores that have melted through the RX and containment, that is above my paygrade... I don't know. Ground water contamination is probably an early risk. I don't know what the worst case is. I don't know if an explosion is impossible. Hope so...

[divvy]

251. concrete and liquid nitrogen ..... interesting

Liquid nitrogen into the hot reactors?

21:28 1 April BREAKING NEWS: Gov't eyes injecting nitrogen into reactor vessels to prevent blasts

maybe not ...... see post 52 and 216

[divvy]

353. The Putzmeister on the job

photo of the putzmeister cement pump on the job



edit: from this DU thread http://www.democraticunderground.com/discuss/duboard.php?az=view_all&address=439x909635

[divvy]

222. du discussion link

du discussion link http://www.democraticunderground.com/discuss/duboard.php?az=show_mesg&forum=439&topic_id=773838&mesg_id=773838

Another discussion here: http://www.democraticunderground.com/discuss/duboard.php?az=view_all&address=439x778940

[divvy]

223. Smoke apeared and disappeared at another nuclear facility

Smoke apeared and disappeared at another nuclear facility http://english.kyodonews.jp/news/2011/03/82065.html

One problem with using multiple diesel generator sets is that the sine waves must be synchronized before and while they are connected to a common buss. "Single phasing" a control panel (if that is what happened) could be a very bad thing depending on which panel it was. I read on the all things nuclear site that the pneumatic compressors which inflate the spent fuel cooling pool gate seals are on a separate circuit.

"Calling the local fire department for help" was the part that caught my eye. Hopefully, it was not serious and calling the fire department was sop.

This particular facility is about 10km from the Fukushima plant that has attracted the worlds attention.

[divvy]

226. calling the fire department in the states is sop

xxxx, calling the fire department is standard operating procedure in the states. It did sound like the fire was in their turbine building... so if it was electrical, it could have had to do with the restoration of off site power to the plant. The design and operation of the plant is to normally synchronize the small generator (in this case, the emergency generator) to the big generator (the grid). If they had the emergency generators running and tried to close in off-site power to the same busses, bad! Even being slightly out of phase can shake the entire turbine building, when you synchrnize the main generator to the grid. You would have to shutdown the emergency diesels (causing a total plant blackout)... close the main busses into the grid to retore site power... and then restart the emergency diesels including synchronizing the EDG to the grid. Doing this from a blackout condition is not something any of those plants have ever done before (I imagine). Their experience with this phenomena is to synchronize their main generator to he electrical grid, not trying to restore normal power while running on emergency power. Nuclear plants are designed with 2 redundant sources of offsite power. If one is down, they have a certain amount of time to either restore it or shutdown. These offsite power sources are monitored and if the grid voltages drop, the Units are automatically SCRAM'd (all reactor rods inserted). No plants that I know of automatically SCRAM on an earthquake. Probably all of these nuclear units SCRAM'd because they "saw" low or no voltage on their offsite power sources (coming from the electrical grid). In this case, the national grid or transmission lines to many plants is/are down... or was down for awhile. Running on only emergency generators is way outside their comfort zone... every plant in such a condition is in a site emergency.

[divvy]

230. wikipedia knows everything

Wikipedia knows "everything"... http://en.wikipedia.org/wiki/Alternator_synchronization

[SidDithers]

224. This thread must set the record for most unanswered posts by a single poster...nt

Sid

[Yo_Mama]

225. I love this thread

Thanks to Divvy again.

[divvy]

229. correlations of aging technology and technicians

xxxx, don’t underestimate your contributions. I say this for several reasons. First the public is illiterate and reasonable discussion serves perspective and education. Also, when it comes to all things technical, I find that servicing aging equipment becomes more of a problem as the technicians familiar with those systems retire. I am one of the few in our plant who is familiar with wire-wrapped controls that used dental floss for ty-wrapping. I could also hook up a Winchester drive and perform the necessary “dos wizardry”. The new stuff, well not so much. This is to say there is a useful correlation between the vintage of the equipment and the vintage of the technicians. Please don’t loose sight of that.

This may lead to the next unaddressed point in discussion:

The correlation between aging technology, aging technicians, and obsolete parts. Maybe planned plant obsolencence by law?

[dixiegrrrrl]

231. Divvy, if you could, please continue to add to THIS thread.

You have so much day to day information already on this thread, it makes it easier for us to follow along.
I would rather bookmark ONE thread than the dozens that appear every day which only cover each new headline as events continue.
Pretty please....:hi:

[divvy]

240. Yes, old technology is a problem

These older nuclear plants have lot's of old technology in them. There are many reasons - 1) it is almost as expensive to modify the plant as it is to build one, 2) reluctance to be the first to upgrade (risk of being first), 3) plants built in early 70's were built with 10 year old design (and parts). The reports of high radiation in ground water seem to indicate a full core meltdown breaching the reactor and containment. Rehulator, it is sad, but those people left in the evacuation area... I don't know what to say. There just doesn't seem to be much good news from the scene.

[divvy]

233. legacy products

I have designed and built CNC equipment, and some of the “older” stuff is what Siemens or GE would call their “legacy” products. In some cases there is only a single person available to answer technical questions. I have even modified several circuit boards because the chipsets are no longer available. $100 per hour charges for phone support are not uncommon.

[divvy]

234. radiation is affecting electronic devices

I'm also told that electronic controls are no longer relaible at the affected plants because the radiation interferes with the electronic signals. For the same reason, robots won't work. Even if suicide-mission volunteers are found, is there any way to control a reactor using only hands-on controls?

Not that I'm any kind of expert, but it sounds like it's too late to stop one or more complete meltdowns.

xxxxx, in response to your question about the width of the island: MAP. Looks like about 200km, but with prevailing west winds and 1000m-high mountains in between, I imagine the (more sparsely populated) west coast won't get much impact. Even so, 20-30 million people could be affected--almost a quarter of the country!

[divvy]

235. more on planned obsolescence

YES. I retired early about 18 years ago!

Sure, this is a concern. In fact, the graveyard of designing nuclear power reactors since three mile island means fewer technical-types are left. The Naval Nuclear Program has been sustained at places such as Knolls Atomic Power Laboratory in Niskayuna, NY...with designers, etc. But the challenge in commercial nuclear is loss of technical design/experience and know-how.

Does this type of generic obsolescence affect nuclear plants also? Is there a planned obsolescence in the nuclear industry where after “x” number of years a retrofit or shutdown is required?

IMHO There is not the classical "planned obsolescence." But surely the development of things such as Computers and greatly enhanced chip designing has relegated some nuclear reactor sites as being "old."

Furthermore, two key technical items are limiting to the age of plants. The steam generators have thousands of thin tubes, which can develop "holes/leaks". One can plug some at each end. But there comes a time the tubes are unusable. Fortunately these can be replaced, but at a high cost.

The second is the integrity of the pressure vessels due to neutron/radiation bombardment...it makes them become brittle, subject to fracturing. This is assessed analytically, as well as perhaps some selected testing of the materials involved. But always a judgment call to a degree. Replacement is a huge effort...almost like getting a new reactor.

It will be interesting to see if the Vessels and Piping did or did not fracture with the very large earthquake, as these are old reactors.

[divvy]

236. Robots have a role to play

Robots have a role to play. Japan has focused on industrial and consumer applications robots. US has focused on research robots for space, military, nuclear and underwater applications. Ironically, Japan has thousands more robots than US.

http://www.scientificamerican.com/article.cfm?id=robots-arrive-fukushima-nuclear&WT.mc_id=SA_WR_20110330

http://www.asme.org/kb/news---articles/articles/global-impact/rescue-robots-aid-japanese-recovery

http://www.guardian.co.uk/world/2011/mar/29/japan-nuclear-plant-us-robots

[divvy]

248. likely not quite as dire as one could envision ....

It is likely not as dire as one could envision.

Sure, they are older..and newer control systems such as panels, etc likely in place. The challenge is more in getting a backup piece of gear. But most reactors have spares. And when they don't, "Engineering" is tasked to develop or find a suitable alternative, often ahead of time.

But these older systems "fit like a glove" to the workers involved. Like an aging house. You get a good feel for the equipment. And retiring workers are tasked to train backup people, who learn that specific system.

A story.

In the Navy Nuclear Submarine Program, the designers designed a sub, planning to build X number in production. The first reactor became a land-based "prototype" at a specific site on ground, used to train sailors and exercise the reactor. Then a first submarine was built.

But occasionally, that sub line was not ever continued...no build out. But the "unique" sub was kept in service. Problem is, few sailors wanted to be assigned to a one-of-a-kind sub. Except for the (I'll be generous here) UNIQUE, UNUSUAL TYPES...MAYBE MISFITS. However, these guys really knew their equipment. Nuclear-geeks so to speak.

I visited a few times, troubleshooting.

These guys were the best operators around...almost making careers on that boat. Like, the inmates ran the asylum! CEOs changed, but not these guys.

Of course, anybody who stays underwater for months has a screw lose, somewhere. Wait awhile, and you will find it. At least, that's the saying.

Similar things were said about troubleshooters :-)

[divvy]

249. The vintage of some of this equipment

The vintage of some of this equipment is potentially a concern. To create a variable speed drive system without high current scr's of today, they probably coupled an ac motor to a DC generator (or alternator). All generators / alternators create AC current the difference being that the "generator" rectifies the AC sine wave mechanically. It does this at the commutator bar which is connected to the armature of the alternator. Brushes ride on a segmented ring which spins with the armature and the DC current (with ac ripple) is produced at the + and - leads. The DC voltage can then be varied on a DC motor (the prime mover) to create a variable speed drive system. The point is that if such systems are still in use, then repair parts are going to be a major issue.

This is just one hypothetical example of how aging technology can become a concern if there is no active plan to retrofit it with modern "off the shelf" parts. This problem is ongoing. Ask anyone who ever bought last years best phone, PC, or gaming system.

[Yo_Mama]

246. That's what I think is necessary

You're making an important point.

First, there really were advances in design for nuclear reactors. Just take even the bottom-rod design of the those old reactors. There are so many penetrations into the lower reactor vessel that it's hard to imagine all of the seals are intact under conditions such as seen at Daiichi.

Reactor 1 at Daiichi is 40 years old and really older in terms of design vintage. So there is going to be a knowledge problem.

And then there is some degradation of materials with age. Under normal operating circs perhaps not much, because normally radiation levels in those reactors are pretty low. But the age of the basic materials isn't an asset.

I never thought the US should recommission some of our reactors, but yet we keep doing it. I think it's because it's just easier to recommission, but there is a BIG potential price to pay.

[divvy]

232. 1000 bodies left untouched due to radiation

I hadn't seen this before. Not sure if you guys have seen it...

http://english.kyodonews.jp/news/2011/03/82200.html

[dixiegrrrrl]

237. How much more awful can it get?

Not even the dead are spared this unfolding tragedy.

[divvy]

238. There is a second report here

there is a second report here: http://www.scpr.org/news/2011/03/31/radiation-slows-recovery-dead-near-japan-plant/

[Hubert Flottz]

239. Ann Colter swears that radiation "won't hurt anyone"...

I suppose that Mad Ann Colter hasn't watched anyone suffer and die from cancer. Cancer will hurt you. Cancer will hurt your family and your friends and even the unborn. There will be hurt for generations from this calamity. Worse than Chernobyl? Maybe already.

[divvy]

242. more du discussion link

interesting du discussion link here: http://www.democraticunderground.com/discuss/duboard.php?az=show_mesg&forum=439&topic_id=776508&mesg_id=776508

[divvy]

243. Entombing the plant with cement?

Entombing the plant -- there may be some that think the nuclear plants in Japan can somehow be buried in concrete like Chernobyl. These are light water moderated nuclear plants and spent fuel storage pools... it isn't a graphite reactor. You could put a concrete structure around the facility and it would help with shielding and the spread of contamination. It isn't a viable way to store spent fuel, though. The only way I know of to store fuel is under cleaned and cooled water... or dry in specially designed cement casks. You can't just pump cement into the pool or reactors... or at least, I don't think so. Cement could be pumped under the plants to slow core decent into the ground. I see that these cement pumps can also be used to pump water. I don't know what kind of spent fuel storage racks these plants have, but the ones used at our plant required that silica be kept very low. These pools are "off the chart" for silica. With all the salt pumped into the reactor and fuel pool, there is lot's of HCl (hydrochloric acid) in the reactor and pool... acidic water conditions. Cracks propagate faster w/ a lot of chlorides. Even if you build a cement structure around the facility, you need fuel pool cooling and a new water cleanup system for each pool... and perhaps new cranes and support systems to remove the spent fuel for permanent disposal. The fuel in the reactor needs a core cooling system... after a decade or more, it might be possible to remove the fuel from the RX. For the cores that have melted through the RX and containment, that is above my paygrade... I don't know. Ground water contamination is probably an early risk. I don't know what the worst case is. I don't know if an explosion is impossible. Hope so...

[dixiegrrrrl]

245. Excellent close up high resolution clear pictures of damage at reactors.

http://www.democraticunderground.com/discuss/duboard.php?az=view_all&address=439x785659

anyone care to comment on what they are seeing?
I am not seeing any place for the spent fuel pool to be intact.

[divvy]

260. Every design is a little different

the square buildings with a lot of damage on the top is the reactor building. The long rectangular buildings adjacent to the reactor buildings is the turbine building, I think. The Main Control Room (MCR) would be in the Turbine building, I think. The MCR is pretty heavily shielded and has its own ventilation system, if power can be restored to it. I would like to be more definite, but I can't. Every site is a little different... there are even plants that have turbine and condensers outside to the elements, so I can't be sure. Hope they have really found the source of the leak to the sea water... there really had to be one to get those levels of radioactive material in the ocean. They are having progress in getting new power to the RHR pumps. They will have walk down the piping to make sure it hasn't been damaged. Normally remote powered valving will probably have to be manipulated manually (sending people to the valve to operate the manual override). Getting shutdown cooling on will be a big step. Hopefully, one loop can be in core cooling mode and the other loop used to cool the torus suppression pool. They also need RHRSW (service water for heat sink) for suppression pool and core cooling. RHR also has a low pressure injection mode LPCI to put torus water into the vessel. I see the big concrete pumps are being converted to pump water before being shipped to Japan. I still am fuzzy on the use of nitrogen. BWR's typically have their drywell inerted with N2 while running... to mitigate H2 formation and avoid explosions in the drywell. Maybe that is what they want to do, re-inert the drywell.

[divvy]

261. what caused turbine roof damage

what could have caused the holes in the roofs of the long regtangular buildings water-side of 3 and 4?

[divvy]

262. turbine building roofs

What caused the holes in the turbine building roofs? There are a lot of things that could have caused it, because most of the equipment is not seismically qualified in the turbine building and there was a very bad earthquake. If I had to guess - the main generator has water running through it for cooling... it could have been (another) hydrogen explosion ---- the turbine could have had a severe rotor rub and ejected a blade though the turbine housing and roof --- the condenser off gas system can have explosive mixtures of hydrogen in it... without power or any dilution steam, hydrogen could have exploded in the hot recombiner. I don't know, but I agree that it looks like something happened there. It would be very difficult to restart a BWR reactor that had boron injected into it... I don't think it has ever been done. The injection of seawater caused unimaginable damage. Oh yes, all 6 reactors are totaled... big time... no doubt in my mind. I doubt that 5,6 escaped very severe damage to the RX and fuel. I hear reports that Tepco employees think they are on a suicide mission... recruits think they face certain death... Tepco should have more control of site activities than that... there are radiation protocols for the worst of conditions. They shouldn't be giving people lethal doses of radiation.

[divvy]

263. There is water leaking from an electrical conduit

The leaking water from an electrical cable trough... If they can stop the leakage flow path to the sea, that is great. We don't know the source of the water, though. If it was feared to be from a breeched containment, nothing about plugging this leak path from the site changes anything... except that the nasty stuff is bottled up onsite. This s a good thing for mitigating the spread of radioactive material... it really does nothing or says anything about the condition of plant equipment.

[divvy]

264. They will try some polymer on the power cable pit

Attempts to plug power cable pit with cement haven't stopped the leak so far. Next, some polymer will be tried. http://english.kyodonews.jp/news/2011/04/82805.html

[divvy]

266. I don't expect much luck with concrete

I don't think they will have much luck just pouring concrete into a crack especially if there is flow through it and it is under water. I am sure there are products that can do it, though. Wouldn't it be good if therevwas some way that the people having to deal with this issue had the capability to tap the Internet. I am sure somebody out there in the ether knows how to plug that crack.

[divvy]

268. Wrapping in sheets?

Wrapping the hot site in sheets/shields? http://english.kyodonews.jp/news/2011/04/82921.html

[divvy]

247. no cement pump news in japan yet

US nuclear recruits to Japan http://ca.news.yahoo.com/exclusive-wanted-u-workers-crippled-japan-nuke-plant-20110331-165506-832.html

One would think that the rush to fly in the biggest concrete pump in the biggest Russian cargo plane would be big news in Japan. But I don't see them in the headlines at Kyodo News & Nikkei, or in the open stories at Kyodo News. May be all this will just spook the Japanese public.

http://english.kyodonews.jp/news/

http://e.nikkei.com/e/app/fr/tnks/newssubject.aspx

It seems that stories in Japan are more on the form of govt aid and control for Tepco, and whether BOJ should buy reconstruction bonds (ie more Japanese QE).

I think that initially, they might use big pumps with huge booms to remotely throw water or other liquids in the hot spots.

[divvy]

250. more errors in the news .....

Can you believe these breaking news advisories (headlines only)? Error again?

12:08 1 April NEWS ADVISORY: Nuke agency expresses 'strong regret' over erroneous nuclide analysis
11:58 1 April NEWS ADVISORY: Groundwater highly likely polluted with radiation despite TEPCO error
11:58 1 April NEWS ADVISORY: Part of TEPCO data on groundwater, trench contamination had error: agency
Previous story on high radiation in ground water http://english.kyodonews.jp/news/2011/04/82390.html

[divvy]

252. cement and liquid nitrogen ... interesting

Liquid nitrogen into the hot reactors?

21:28 1 April BREAKING NEWS: Gov't eyes injecting nitrogen into reactor vessels to prevent blasts

maybe not ...... see post 52 and 216 above. Whatever their plan, I hope they are successful.....

edit to add this now-available link http://english.kyodonews.jp/news/2011/04/82625.html

[divvy]

256. in response to the link above

in response to the link above ..... I am not sure of the rationale for liquid N2 instead of water... H2 explosions were mentioned. That isn't intuitively obvious to me unless they think they can keep the concentration of H2 below the explosive concentration. H2 generation means that cladding is melting. This means that he core is not being adequately cooled with water... perhaps due to a vessel breech. I am clueless how they plan to deliver liquid nitrogen to the core inside the RX. Anybody have an idea how you would do that? One advantage of liquid N2 is that it may not be a good moderator making an uncontrolled chain reaction less likely. I don't think that liquid N2 and water mix well, though. Anybody know what this resin does? I assume that it puts a "crust" on things. I don't understand why Tepco can't get its numbers right.

[divvy]

257. Thanks xxxxx

Thanks xxxx... I remember xxxxx talking about freezing the ground under the site. I think that makes sense. I don't understand the " entombing" like Chernobyl. A graphite reactor is built a lot different than a light water reactor... I don't see how you can just dump concrete on a BWRs fuel. Maybe I am wrong... maybe you can. I think there has been H2 developed both places, but I think the RX buildings blew after venting the RX that put H2 into the building instead of up the stack (because SBGTS ventilation system was off due to know power). I can't see using liquid N2 on fuel pool

[divvy]

253. DU thread ..... Nova covers Japanese disaster

The scope of the disaster and human tragedy, and the science behind it.

http://www.pbs.org/wgbh/nova/earth/japan-killer-quake.h...

[divvy]

254. Chernobyl sarcophagus

Construction of the Chernobyl sarcophagus.

The first task before construction started was to build a cooling slab under the reactor to prevent the hot nuclear fuel from burning a hole in the base. Coal miners were called up to dig the necessary tunnel below the reactor and by June 24, 1986 four hundred coal miners had built the 168 metre (551 ft) long tunnel. When the building became overly radioactive it became impossible to directly screw down the nuts and bolts or apply any direct welding to the sarcophagus, so this work was done by robots.

The seams of the sarcophagus, however, were not properly sealed. The entire construction process consisted of eight stages: clearing and concreting of territory around reactor unit 4, erection of initial ferro-concrete protective walls around the perimeter, construction of separation walls between units 3 and 4, cascade wall construction, covering of the turbine hall, mounting of a high-rise buttress wall, erection of supports and installation of a reactor compartment covering and finally the installation of a ventilation system.
More than 400,000 m3 of concrete and 7,300 tonnes of metal framework were used during the erection of the sarcophagus.

From Wikipedia here http://en.wikipedia.org/wiki/Chernobyl_Nuclear_Power_Plant_sarcophagus

The old sarcophagus will be replaced.

On September 17, 2007, it was announced that a new steel containment structure named the New Safe Confinement (NSC) would be built to replace the aging and hastily-built sarcophagus that currently protects reactor unit 4. The project, financed by an international fund managed by the European Bank for Reconstruction and Development (EBRD), will be designed and built by the French-led consortium Novarka, which includes the companies Bouygues and Vinci. Novarka will build a giant arch-shaped structure out of steel, 190 m (623 ft) wide and 200 m (656 ft) long to cover the old crumbling concrete dome that is currently in use.

This steel casing project is expected to cost $1.4 billion (£700 million, €1 billion), and expected to be completed in 2013.<9> A separate deal has also been made with the American firm Holtec to build a storage facility within the exclusion zone for nuclear waste produced by Chernobyl.

From Wikipedia here: http://en.wikipedia.org/wiki/Chernobyl_Nuclear_Power_Plant

[divvy]

255. Putzmeister 70 meter concrete pump

Short video of the Putzmeister 70-meter concrete pump.

http://www.youtube.com/watch?v=VqOk7lR0970

[divvy]

258. radiation leak source to sea confirmend

Water with high levels of radiation has been confirmed to have seeped into the sea from the No. 2 reactor at the troubled Fukushima Daiichi nuclear power plant, government officials said Saturday

<snip>

The government ''wants (the utility) to start the operation of covering the crack in concrete as soon as possible,'' said Hidehiko Nishiyama, a spokesman for the Nuclear and Industrial Safety Agency.

<snip>

The radiation level in the pit at the No. 2 reactor was more than 1,000 millisieverts per hour, according to the agency.

<snip>

TEPCO is considering using a large artificial floating island, a so-called ''megafloat,'' to store the tainted water, the agency said, while it will also inject nitrogen into the containment vessels of the plant's reactors to help prevent the risk of more hydrogen explosions.

<snip>

A 15-member advance party of a U.S. military radiation control team arrived at Yokota Air Base in western Tokyo.

Full story here: http://english.kyodonews.jp/news/2011/04/82753.html

[divvy]

259. self delete

self delete

[divvy]

265. Good DU discussion link on radiation.

Good DU discussion link about the April 6th radiation forecast. http://www.democraticunderground.com/discuss/duboard.php?az=view_all&address=385x569377

See also post 212 above. We still may need political help locating an agency which tracks Caesium-137 cumulative totals. This information should be made available to the public.

[divvy]

267. NYT article

I want to call your attention to the NYT article today "from afar, a vivid picture of Japan crisis" in which the art of atomic forensics is used to document what has been happening there, perhaps better than what the official public statements have done. see http://www.nytimes.com/2011/04/03/science/03meltdown.html

I especially want to call your attention to the Stanford meeting on this noted late in the article. I found the meeting documented at http://cisac.stanford.edu/events/the_nuclear_crisis_in_japan/

and very informative slides at http://iis-db.stanford.edu/evnts/6615/March21_JapanSeminar.pdf

[divvy]

269. Here is an obscure nuclear disaster ....

Here's a nuclear disaster readers may have never heard of:

http://en.wikipedia.org/wiki/Soviet_submarine_K-431

Snippets:

Originally the Soviet submarine K-31, the K-431 was a Soviet nuclear-powered submarine that had a reactor accident on August 10, 1985.<1> An explosion occurred during refueling of the submarine at Chazhma Bay, Vladivostok.<2> TIME magazine has identified the accident as one of the world's "worst nuclear disasters".<1>

Nuclear reactor plant disaster

The K-431, completed around 1965 as unit K-31, was a Project 675 (Echo II) class submarine with two pressurized water reactors, each 70 MWt capacity and using 20% enriched uranium as fuel.<3> On 10 August 1985, the submarine was being refueled at the Chazhma Bay naval facility near Vladivostok. The submarine had been refueled and the reactor tank lid was being replaced. The lid was laid incorrectly and had to be lifted again with the control rods attached. A beam was supposed to prevent the lid from being lifted too far, but this beam was positioned incorrectly, and the lid with control rods were lifted up too far. At 10:55 AM the starboard reactor became prompt critical, resulting in a criticality excursion of about 5x1018 fissions and a thermal/steam explosion. The explosion expelled the new load of fuel, destroyed the machine enclosures, rupturing the submarine's pressure hull and aft bulkhead, and partially destroyed the fueling shack, with the shack's roof falling 70 meters away in the water. A fire followed which was extinguished after 4 hours, after which assessment of the radioactive contamination began. Most of the radioactive debris fell within 50-100 meters of the submarine, but a cloud of radioactive gas and particulates blew to the the northwest across a 6 km stretch of the Dunay Peninsula, missing the town of Shkotovo-22, 1.5 km from the dock. The contaminated forest area was later surveyed as 2 square km in a swath 3.5 km long and 200 to 650 meters wide. Initial estimates of the radioactive release were about 2 MCi of noble gases and 5 MCi of other fission products, but most of this was short-lived isotopes; the estimated release inventory one hour after the accident was about 1000 Ci of non-noble fission products. In part because the reactor did not contain spent fuel, the fraction of biologically active isotopes was far smaller than in the case of the Chernobyl reactor accident.



Enjoy...

BTW...The worst from an operational standpoint is a reactor going "prompt critical" ...out of control...like this Russian submarine The Chernobyl accident was a "relative high disaster" to the local people because of an absurd lack of containment by Russia for the entire reactor.

The Japan accident is more far reaching...reactors melting, going into the earth...could be the ultimate test. Hence the USA term "China Syndrome"...melting all the way from USA to China...(of course, a technical impossibility.)

[divvy]

270. new to the group ......

I am new to the group, but so happy to find you all. I, too, am retired; I was a mechanical engineer at a National Laboratory managing a team of "independent reviewers" for the NRC reviewing license applications for the Westinghouse AP1000, Areva's ERP, and others (I have to refresh my memory of the list). In particular, we did reviewed all these new nuclear power plant designs for seismic loading. We never found the new designs to be safe under an earthquake load. And the NRC department reviewing seismic loading on mechnical equipment was totally "in bed" with the nuclear industry. As we tried to point out to the NRC the shortcomings in these designs, we were met with unbelievable to pressure to approve them anyway! So much for the NRC being a credible regulator. Very disconcerting.

For one thing, the industry and NRC did not have the correct seismic vibration loading signature representing the seismic load. They refused to acknowledge the damaging high-frequency components in the loading. So they will never get a correct response from the structures. And the NRC is compartmentalized such that one department is responsible to review only "mechanical systems" for seismic response, while another NRC department reviews instrumentation and processors without testing and reviewing the electronic (software and hardware) to seismic loading. The US instrumentation industry is well aware of electronic malfunction when components are subjected to vibration, but this aspect is not captured anywhere in the NRC review. The NRC's instrumentation department says, "We are not responsible for earthquakes" and the NRC's seismic reviewers say "We only review mechanical systems, so we are not responsible for instrumentation." There is a big gap in the NRC review of reactors up for licensing.

Lastly, there are major deficits in the NRC review process, which changed around the year of 2009. Before 2009, the NRC was authorized to shut down a new reactor at any point in the design and construction phases--even after a nuclear power plant was newly built, if there were any problems with the "as-built" facility as it deviated from design or design problems became known from the as-bulit plant, the NRC could halt the process at any time. NOW, after 2009, the rules were changed under the Bush administration. After 2009, the NRC only has authority to intervene during the design phase. Under the new rules, after the design has been approved, the NRC no longer has authority to intervene, even if design flaws or construction deficits are found to exist. This is another very disturbing observation. The nuclear industry lobbied for these changes in the licensing process because of the fear of spending billions to design and construct a new nuclear power plant and then be scrutinized with the possible outcome of the NRC shutting down the operation. So the NRC was stripped of true authoity and power in the NPP review process, I'm afraid. The NRC should be worried under the new scrutiny.

Lastly, I know for a fact that the aged reactors in Japan were also not properly designed for the correct seismic loadings. What a sad (and dangerous) set of affairs.

[divvy]

271. seemed to survive the earthquake pretty well

The plants in Japan seem to have survived the earthquake pretty well... it was the plants that had inadequate tsunami protection that caused the big problem. Is there something I haven't heard

[divvy]

272. Fukushima earthquake measurements

Specific data on earthquake measurements (gals) around some Fukushima reactors are in this link. It seems that the design limits were exceeded but there was no direct earthquake damage to the reactors. http://english.kyodonews.jp/news/2011/04/82655.html

[divvy]

273. fuel rods self-ignite

The experiences I describe are mostly as "food for thought," and less about explicit diagnosis of the specific event. I do wonder though, do we know exactly when power failed, and did the reactors all shut down in proper sequence, and did the systems that did have power (backup or otherwise) continue to function and cool properly after the earthquake, and did the integrity of the spent fuel pools continue to hold water and not be structurally damaged -- was it the earthquake or the tsunami that did the damage at these various times to these structures and components? I'll bet the earthquake mortally wounded the plant -- not necessarily the reactor per se, but some of the pumping systems and control systems and the structural integrity of the pools -- even before the tsunami hit.

And by the way, we performed experiments at my Lab demonstrating for the NRC that zirconium encased spent fuel rods self ignite when exposed to air. The NRC is well aware of the vulnerability of the spent fuel pools--vulnerable to natural disasters and terrorist attacks. I find it remarkable that anyone would rely on an open and vulnerable concrete pool to hold spent fuel rod reactor cores when loss of water has such high consequences. And there were likely 6 to 8 spent cores housed in one of the facilities.

I believe this Japanese disaster will be shown to be by far the worst nuclear accident -- way way beyond Chernobyl. And I am certain the Japanese rad workers heroically trying to control the radiation WILL die of radiation exposure, although I imagine they already know their destiny as they do the work. Still we can pray for them, although I think more appropriately we should honor them and thank them for knowingly giving their lives in the line of duty.

[divvy]

274. a piece of cake

I was in the Naval Nuclear Submarine Program, so did not have much interaction with NRC and its organizational structures...so can't comment on some of your observations.

I had a piece of cake...Admiral Rickover.

I agree, it will be interesting to see if the initial earthquake caused initial serious harm. I have witnessed testing of Submarine reactor component shock tests (had to withstand large bomb explosions), It would amaze people to see large nuts spinning off of bolts, like bullets going across a room, for marginal or unsuccessful designs. In fact, most bolts are now lock-wired on to hold them in place.

From photos it appears some of the auxiliary piping held up in Japan. We will learn of the reactors eventually. One thing is I would assume commercial plants have cameras on-going full time observing the reactor spaces/pumps etc. Where are the films? Destroyed? Or did these older arrangements have no camera ability? We will see.

I, too, participated early in xxxxxx my surprise that the spent fuel in the swimming pools was not "under containment." Last week I was at the Florida xxxxx Power Plant, and in speaking with the head of security, learned the pools there are under the main containment...as far as I could tell/verify.

I will be posting more on whether this will actually be the ultimate test for reactors...a worse case incident. You couldn't do this in a test. If in the end radiation spread is moderate...contained locally, then we might see people have more acceptance, not less, of commercial nuclear power.

Still interested in the degree of "meltdown" and whether it has gone through any vessel bottoms, into final containment. And what will eventually happen.

[divvy]

275. The truth tends to not be told

Thank you to all who have extended welcome. My first admission is that I am not a nuclear engineer by training, but rather a mechanical engineer who worked at a National Laboratory in various nuclear energy departments for about 19 years. I performed many structural analyses, designed and managed construction of a nuclear waste charaterization facility, reviewed containment of high level waste proposed for Yucca Mountain, and lastly managed reviews of new NPP licence applications for the NRC. That is my the disclaimer under which I provide my honest opinions and assessments.

After more evaluation uncovers the true events at Fukushima, and if these true stories are ever made available to the public, I believe we will find that the stored and subsequently released radiological inventories will be many times greater than that released in Chernobyl. Although the reactor vessels may have successfully remained intact at Fukushima (still to be verified), the inventory in the spent fuel pools could be anywhere from 6 to 40 reactor cores. At Chernobyl, one operating core was released, although I do not know if spent fuel was co-located in Chernobyl, but the inventory was that at one reactor--not 6-40 cores available at the 5 reactors and their co-located spent fuel cores.

When the spent fuel pools lose water, the zironium encased fuel rods -- uncooled and exposed to air -- self-ignite explosively. I believe we will find that some of the fires, smoke, and explosions were due to the uncovered spent fuel rods self-igniting, and the radiation released will be from the many spent reactor cores on the Japanese site. I will try my best to follow the post-mortem of the event to see if these details are released.

The truth tends not to be ever be disclosed. I learned of the gory details of the events at Three Mile Island (TMI) because I held a security clearance and had access to classified briefings. For example, did you know that a TMI plant operator was impaled and lifted to the top of the containment vessel by a nuclear reactor rod when the reactor vessel exploded? The public does not tend to get such information.

Also, the radiation levels experienced at the Fukushima plant and at various distances away, and the great distance of the exvacuation zone are also indicative of the incomprehensible quantities of radioactive material released. The other nuclear engineers and operators in this discussion will likely also have a "feel" for the meaning of these "clues." For these reason, I believe that Fukushima will be found to be much much worse an accident than Chernobyl--not even close in comparison.

Lastly, an explosive loadings on equipment and instrumentation is not the same as seismic loadings on these systems and components. To design equipment, systems, and instrumentation for explosive loadings will not make them safe for seismic loadings. They are different and require different design requirements. These systems and components could survive and explosion and not survive a seismic event. As far I knew (by 2010), no seismic testing has ever been done on NPP systems, equipment, controls, instrumentation, processors, etc... The control software also has to be programmed to handle a seismic event and properly shut down, continue cooling, etc.... The software in NPPs has also never been tested under a seismic loading, as of my last experience in the field in 2010. My team reviewing the seismic aspects of new NPP licensure informed the NRC of these deficiencies and we were met with distain for our "uncooperative" stance. I was personally pressured to "knuckle under" by the NRC seismic point of contact, insisting that my team's purview was to evaluate single pieces of mechanical equipment and not evaluate whole operational systems including instrumentation and controls. In my opinion, the NRC seismic review process was/is greatly deficient.

Also, the Japanese have had previous damage at other reactors due to seismic events. But none made news because the effects were locally contained. We all knew this fact of the potential for seismic damage and we pointed to the Japanese history to try to explain to the NRC the very real possibility of seismic disasters. Also, past used seismic vibration loads were found to not be correct; they were missing the high vibration content in the loading signature. This error in proper seismic loading was/is true for all NPPs around the globe. Maybe now the NRC will wake up. Although the NRC has such reduced authority over the nuclear industry, it is quite scary. Perhaps the investment community (GE, Westinghouse, and other consortiums of investors) will deem the enterprise too risky. But maybe risk does not matter because by law the US taxpayer will pay for any US disasters.

Thank you for listening to my perspective. I'm quite upset with these preventable disasters: unjust lost resources, damage to people and the environment, collusion between regulatory agencies and the government, and other ineptitudes that are tolerated in the face of unimaginable consequences. The radiation released will be with us for millions of years and it will move through the food chain as a ever-present poison. Information is intentionally withheld so the public does not truly know what has happened and its true impact.

[divvy]

280. your perspective is important

thank you and welcome

[divvy]

282. thank you for spent fuel core info at Fukushima

I appreciate finding and sharing information about the configuration of the spent fuel cores in storage at Fukushima; I admit my surprise at the disclosure. I will review these materials as soon as I can. The inventory of these spent fuel cores is available to flow into the ocean through the ~18 centimeter cracks found in some of the spent fuel pools. Perhaps the US is sending the largest concrete pumps in existance to try to plug the cracks in the pool? Or possibly to entomb the spent fuel cores with a boriated concrete mixture? Should be interesting to follow the next attempts at mitigating the on-going release of massive amounts of radiological materials.

[divvy]

289. Are you thinking of SL-1?

xxxxx wrote:

The truth tends not to be ever be disclosed. I learned of the gory details of the events at Three Mile Island (TMI) because I held a security clearance and had access to classified briefings. For example, did you know that a TMI plant operator was impaled and lifted to the top of the containment vessel by a nuclear reactor rod when the reactor vessel exploded? The public does not tend to get such information.



Are you sure that information was about Three Mile Island? That is what happend with the SL-1 accident.

[divvy]

331. Design basis earthquake survival does not mean no damage

Nuclear power plants are designed to safely survive a design basis earthquake. That is not the same thing as saying it won't be damaged by it. There is a lot of non-Safety Related equipment in the plant required for normal operation of the plant that is not seismically qualified. Normal feedwater, much of the BWR's steam lines, etc etc are considered NSR and is not seismically qualified. None of the Radwaste System is Safety Related. A lot of this piping contains radioactive water. Safety Related is reserved for those systems necessary to shutdown the reactor and keep it in cold shutdown. The fuel pool cooling and cleanup system is not considered Safety Related. I would expect that any nuclear plant would require extensive inspection and major repairs after a severe earthquake.

[divvy]

276. the stanford slides were interesting

The Stanford slides were interesting. (see post 267 for the link) I agree entombing the plant doesn't make any sense to me unless you can fill the structure with water that can be cooled and cleaned. The only way to safely take fuel out of water is to put it in a cask designed to hold it, while under water. If you just covered the mess with a building, the contents would heat up and the building would pressurize until all the water evaporated... then the fuel would melt through the bottom of the building. If a 6" thick stainless steel RX vessel might not hold it, why would a new containment building? I got a kick out of the Stanford slide that dismissed the collapse of the reactor building (secondary containment) as having minimal safety significance. For the reactor core, maybe... for the spent fuel pool, give me a break! That was a disaster for the sent fuel pool. It is amazing to me how ignorant so many are/were about the danger present in the spent fuel pool. I recognized the danger almost immediately, because one of my many jobs was the Fuel Pool System Engineer. Before this is over, the fuel pools (with no containment over many of them) will be as big a problem as the reactors, if not more of one. Dr Chu sited concern about one of the fuel pools for the 50 mile evacuation of Americans. I think he gets it! They will have to build a cover over the damaged reactor buildings to cover the spent fuel pools... but that is only part of the problem... they still have to be able to makeup water, cool, and clean the water in the RX and pool. At Chernobyl, they just dropped a lot of cement amd graphite on the core and built a building around it and walked away. These are boiling water reactors, not graphite reactors... they are different. That won't work in Japan.

[divvy]

277. prompt critical

Supporters of nuclear power (like me) lIke to say (not me) that a nuclear power plant can't explode like a nuclear bomb. That is technically true, but a prompt critical can take the reactor to extreme over power in milliseconds. That is what blew Chernobyl apart. That is what blew the SL-1 reactor apart in the US... remember xxxx asking if I had seen a film on it. xxxxxxx

http://www.google.com/images?q=SL-1+reactor&oe=UTF-8&hl=en&client=safari&um=1&ie=UTF-8&source=univ&sa=X&ei=cDOZTavPHsGM0QG0uITxCw&ved=0CDgQsAQ&biw=980&bih=1208 xxxxxxx

As you can see from the SL-1 (really tiny experimental reactor) pictures, it can be explosive. There is a picture of it exploding. That is virtually the same thing that the Russians did with their sub reactor. There is a possibility, though as far as I know it has never happened, that fuel that partially or completely melts, either in the RX or fuel pool, could loose its geometry in such a way that fuel could develop a localized critical and even a prompt critical... resulting in an explosion that would spread really nasty radioactive material over a wide area. That is the worst case if the Japanese have to abandon the site and let the RX's and fuel pools go to he//. Melting down and contaminating the groundwater is another bad outcome. I am not sure it is worse, though. A large explosion at the site would be very very bad. I don't see a recovery path from that tragedy. Today, they discovered 2 missing TEPCO employees dead in the basement of one of the plant's turbine buildings. I did not hear the cause of death... fallen heroes.

[divvy]

278. SL-1 photo

more at http://www.google.com/images?q=SL-1+reactor&oe=UTF-8&hl=en&client=safari&um=1&ie=UTF-8&source=univ&sa=X&ei=cDOZTavPHsGM0QG0uITxCw&ved=0CDgQsAQ&biw=980&bih=1208

[divvy]

281. death by reactor rod

Wow, how interesting. Nuclear rods turning into projectiles from an overpressurized failed reactor vessel that loses coolant -- is a repeat and expected mode of failure! At TMI, a nuclear reactor operator was impaled and pinned to the top of the inner containment vessel. The only good news is that the inner containment at TMI did not fail. At least death-by-reactor-rod is immediate, unlike the slow painful death of radiation exposure above 200 RAD. If you track the exposure of the Fukushima workers as reported in the news, I expect death-by-radiation exposure will be the fate of these radiation workers at Fukushima.

[divvy]

279. suppression pool

There are large storage tanks (CST and CCST) that contain water that is (mostly) used as makeup water to the main condenser hotwell (water that is pumped back into the reactor to make steam). Discharging this water would not normally be allowed, but compared to what they are now trying to store... it is tame stuff. This water, via the condensate system, is also the source of water to fill the torus suppression pool. I am not sure what their plans are for the suppression pool, but I would think they would still need it (apparently one ruptured... that could be one source of nasty water after core damage). Getting the core cooling back will require RHRSW... getting LPCI will require torus water. Our RHRSW pumps were in water tight vaults... but it was a retrofit. We managed to flood the turbine building basement when some condenser boots broke. That is where the RHRSW pumps were. Hope theirs is protected from flooding, too. RHRSW is needed to provide the heat exchangers a heat sink (in shutdown cooling). You need to be able to add water to the suppression pool to keep it available as a heat sink... and to maintain the correct level in the pool. Normal emergency procedures depend heavily on the suppression pool, so they need to consider how to keep cool water in it... I would think.

[Rex]

283. So in other words, get caught in that kind of nuclear shitstorm

and die a horrible death! I feel a huge amount of sorrow for the Japanese. This will be the worst man made catastrophe in history imo.

[divvy]

284. Hitachi, GE Turn To Nuke Plant Specialists For Help

GE is Hitachi's tie-up partner in the nuclear power business. They are looking to form medium- to long-term technological partnerships with Exelon Corp. and Bechtel Corp. to restore cooling functions and eventually scrap the reactors altogether.

Top U.S. electric utility Exelon, which operates a number of nuclear plants, drew up recovery plans and handled the scrapping of the No. 2 reactor in the Three Mile Island nuclear accident.

Bechtel, meanwhile, played a leading role in the efforts to contain the Chernobyl nuclear disaster. It also handled cleaning and other tasks at the Three Mile Island site

Story here: http://e.nikkei.com/e/fr/tnks/Nni20110404D04JFN03.htm

[divvy]

287. this has been happening behind the scenes

I think they have all been helping before this announcement. This announcement maybe represents a formal arrangement that will allow each company to talk to the other. Normally, some of these players are competitors. This might also allow them to get paid for their time.

[divvy]

286. Radiation .... which government agency?

There are things that I learned over the years, such as:

Fallout... radionuclide releases... is a very complicated subject. Wind, rain, runoff, ocean current, etc patterns will cause uneven distributions and accumulations of these substances. Distance helps but doesn't guarantee you won't encounter contaminants due in part to the globalized food chain.

Each radionuclide has its own characteristics... some gas, some particulate, different emitters, some water soluble, some not water soluble, different decay half lifes, different biological half lifes, different soil penetration rates, each is metabolized somewhat differently and thus represents its own unique threat to plants and animals. Internal exposures are the greatest threat to the greatest number of people. Age at time of exposure is very important.

To really understand what is going on, very many tests (air, rain water, drinking water, soil, sediments in bodies of water, plants, animals, milk, etc...) must be performed. The tests must look for all of the relevant radionuclides (not all tests detect all of them). There must be targeted testing of things/places where concentrations would show up as well as broader testing of sufficient density and frequency to eliminate large gaps in coverage. Projections of said must be reported as soon as possible. Actual results must be reported as soon as possible.

Individuals and entities must make their own decisions regarding what they consider actionable. Although numerous bodies including the IAEA, ICRP, NRC, EPA, etc have worked to establish limits, said limits are at best a "balance" of conflicting objectives. Setting the limits too low creates anxiety, interferes with commerce, drives up costs for various industries and government, etc. Many believe established limits are set too high... that the assumptions/methodologies/limits don't jive with various real world experiences (Chernobyl, other accident sites and industrial releases)... that current limits can't and shouldn't be relied upon

That's alot of stuff to try to make sense of. I was trying to keep abreast of the news and stitch information together to improve my own understanding. However, that is very time consuming and it distracts from more practical steps.

once again, it would be nice to know which agency was tracking cumulative totals, and to have access to up-to-date information for fact-checking. I am not convinced this will happen without domestic political input.

[divvy]

288. I just read a report stating that TEPCO made mistakes ...

I read a report stating that TEPCO made mistakes in its initial accident response that caused this accident. Here is my perspective in a nutshell. Fuel damage and probably severe damage is almost inevitable in a running nuclear plant that loses all offsite power and all of it's emergency diesels. HPCI and/or RCIC can keep the plant fairly stable for 4-8 hours until battery power is gone. In an earthquake and tsunami ravaged country, getting more batteries or jerryrigging a fire pump for alternative (saltwater) feedwater in 4 hours for 6 Units... very difficult. I think that it would ave been nearly impossible to save the 3 running Units' cores. There was little reason IMHO to lose the 3 Units that were in shutdown prior to the event and there was no good reason to lose any of the 5 fuel pool (5,6 share a pool). The reason this disaster is as big as it is is that certain actions in the first day or two weren't taken. There should have been a fire hose running into each fuel pool keeping it full. If this had been done, fuel wouldn't have melted in the storage pool and that spilled water in the RX building basement wouldn't be nearly as radioactive. The shutdown Units had much more time where action to add water to the RX's would have been successful in preventing major core damage. The root cause of these failures to take prompt corrective action are probably multiple... and you probably had to be there to understand. My guess - 1) chaotic emergency response due to damage to emergency response facilities, 2) inadequate communication due to phones being down, 3) inadequate personnel to deal with so many problems at once, 4) delay in getting offsite help due to ongoing national disaster. Could anyone have done better under these circumstances? I don't know. You would have had to be there... I prefer to think of the emergency response teams as heroes. I think they probably did all they could.

[divvy]

290. Reactor buildings 1 through 3 may become uninhabitable

The monitor told NHK that no one can enter the plant's No. 1 through 3 reactor buildings because radiation levels are so high that monitoring devices have been rendered useless. He said even levels outside the buildings exceed 100 millisieverts in some places.

NHK World News http://www3.nhk.or.jp/daily/english/05_38.html

These reactors need human hands on sight to avoid really big problems.

[divvy]

291. NRC (see also thread starting at post #270)

Interesting blurb in that NY Times article discussing the 03/16/2011 NRC document they gained access to...

'The document also suggests that fragments or particles of nuclear fuel from spent fuel pools above the reactors were blown “up to one mile from the units,” and that pieces of highly radioactive material fell between two units and had to be “bulldozed over,” presumably to protect workers at the site. The ejection of nuclear material, which may have occurred during one of the earlier hydrogen explosions, may indicate more extensive damage to the extremely radioactive pools than previously disclosed.'

Many have been conjecturing that some fuel rods were expelled/vaporized by one or more of the explosions. However, this is the closest thing to a confirmation of that I can recall seeing.

[divvy]

292. The NY Times article

The Times article is quite a read, and very graphic. In addition to saying flat out that things are potentially much worse than than the Japanese have admitted so far, this salient point:

If I were in the Japanese’s shoes, I’d be very reluctant to have tons and tons of water sitting in a containment whose structural integrity hasn’t been checked since the earthquake.

http://www.nytimes.com/2011/04/06/world/asia/06nuclear.html?_r=3&ref=global-home

[divvy]

293. This may sound critical but not meant that way ....

(This may sound critical of your comment... not meant that way. Just sayin'...) There really wasn't any choice but to fill some of the containments with water. Their procedures called for it if they feared losing the structural integrity of the RX vessels. Now that they are partially filled, where they are, there is no place to go with the water, that is now probably highly radioactive. There are no pumps to pump it out... and if there were, they would be without power and probably damaged. GE has the capability to seismically evaluate the consequences of earthquakes on the currently partially filled containments, but I doubt Tepco knows one way or the other. "I'd be very reluctant..." implies a choice... I don't think they have many options at this point. A containment with water is a better barrier to fuel melting through it than a containment without water. If I was a god and could decide whether or not there should be water in the containment or not, I would leave it in there. Would I be thrilled about the danger of another big earthquake? No... For some reason, your comment reminded me of Browns Ferry, where plant management refused to let a fire chief put out a fire in an electrical cable room, because of fear of water damage. "Nero" let the cable room burn, because he was afraid of water damage. It didn't turn out well. You can't let the fuel melt through containment, because you're afraid of another earthquake. Big picture, you are concerned that we haven't seen the worst of this disaster. I share your concern. We are way beyond the point where we have good models for what will happen. It is kind of like the hedge fund with math models that work pretty good until the unthinkable happens. The unthinkable has happened in Japan.

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294. Just to reduce the confusion

Just to reduce confusion, it wasn't my comment; it was a quote from the Times article--specifically, from an engineer who designed reactors for GE. If you haven't read the article, let me recommend it again, as it spins things rather differently from what we've seen elsewhere.

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296. I agree with the assessment that it came from the fuel pools

Sorry, xxxx... I tend to agree that things are bleak... I don't think draining the containment is a plan. Lamenting the fact that they may be vulnerable to damage if they get another big earthquake isn't where I would be most concerned, but maybe he is right... I doubt it, buy maybe... Heck, look around at the site... do you see anything that looks ready for another 9.0? It is pretty good if containment survived the first one. You shake anything hard enough and long enough and it will fail. Until the reactors are in cold shutdown with a reliable (e.g., not dependent on human intervention) makeup water supply, this is an emergency. We are a long way from that. Reports above that nasty particulates were thrown a mile from the site is pretty disturbing... I agree with the assessment that it came from the fuel pools. It means that fuel got at least uncovered... and US claims that one pool went dry is probably true. I don't think the hydrogen explosions, unless they were in the pool, would do that. I had presumed that the hydrogen was generated in the RX and vented to the RX Building. This spread of "pieces of fuel" would say otherwise. The US concern many days ago that a fuel pool was empty was probably correct. If fuel has melted in a pool, then it is credible that a pool would be leaking and the source of the nasty water that has been filling the building basements and was leaking into the sea. These pools are not concrete (people that think so are PWR oriented)... they are made of stainless steel sheet metal. They would not hold up long to contact with melting fuel cladding. Eventually, for both the RX's and the pools, they need to get cooling systems going so that they don't have to keep "feeding and bleeding" to get cooling. For example, if they gently dropped a cooling coil (not resting on top of the fuel) into the pool water and started cooling the water, the evaporation would reduce and they could slow the water input. The RX is a tougher nut to crack. If you can get RHR shutdown cooling mode back, great! I am not optimistic about that on all 6 Units... some, maybe. One alternative cooling method would be to cool the torus water and use it to makeup flow to the vessel with either LPCI or a pump like what is being used to inject seawater/external tank water. Recycling the water would stop increasing the site inventory of nasty water.

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295. Injecting N2 into a RX?

Injecting N2 into the drywell containment is standard operating procedure. Injecting it into a reactor? That is a new one on me. A normal BWR has steam in the top of the vessel. These severely damaged reactors have steam and hydrogen in the top of the RX vessel. The plan is to inject Nitrogen to get the concentration of hydrogen down to where it can't explode. This all sounds very rational. As an old Offgas System Engineer, I know that "we" dilute hydrogen in that system to keep it from exploding, too. It has exploded in the past at a few plants. What do we dilute it with? Steam and a little air (mostly nitrogen). It should work, unless the cladding burns so fast that hydrogen is generated in large quantities and there isn't much steam Amy more. It is probably good that they are thinking of ways to reduce the probability of explosions, though. That would only make the situation worse... and yes, it can get worse.

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297. the press may get better but the crisis won't

Something that surprises me about the crisis in Japan is its long timeline. It has gone on longer without what would seem like a final resolution than I ever dreamed possible. It doesn't get better and it won't go away! The press may, but this crsis won't. They have to beat this thing or it will just keep getting worse. There is plenty of raw material there to contaminate Asia... little alone Japan. This should be a global, all out effort. I don't know if I sense that level of concern. I know many nuclear professionals that are very concerned... I know I am.

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298. building 3 external water cooling systems onsite

It sounds like they are going to start building 3 external water cooling systems onsite. That seems like an imperative to me, because of 1) high radiation in U1-3 facility will make restoration of core cooling difficult, 2) they have to stop dumping so much water into the site for cooling, because the more that goes in, the more nasty water that will have to be released or stored. I read in some stories that they are going to inject nitrogen into some containments... and some say they are going to inject it into reactors... so I am confused... they aren't the same. Exelon has sent a technical team to Japan... an engineer from the plant I worked at has left for Japan. Contamination is spreading pretty badly in Japan... a city outside the evacuation zone as been instructed to evacuate. China, South Korea, and other nearby countries are starting to get more concerned as the crisis seems to continue without a lot of apparent progress to get it under control. You know that radioactive water leak that was flowing out of the crack? That was coming from the turbine building... they need to figure out how that is happening. This is really nasty stuff from the reactor or spent fuel pools... neither are in the turbine building (TB). How did it get there? They need to get their arms around how so much water is flowing to the turbine building. Flooding the TB could make it impossible to get RHRSW (service water for core cooling) running. This leak is large enough that it needs to be stopped... in a week you could have the large rooms filled with this very nasty water. The more water that leaks... the more you have to inject. This is important... that was a lot of very, very contaminated water. It is still accumulating in the TB

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299. It is starting to get difficult to get current Japanese news

Nitrogen injection into reactor #1 continues http://english.kyodonews.jp/news/2011/04/83743.html

Japan complains about sensational reporting by foreign media http://english.kyodonews.jp/news/2011/04/83786.html

Recyclable-Fuel Storage Co. (80% owned by Tepco) resumes peripheral construction work Monday for a facility for intermediate storage of spent nuclear fuel in Mutsu, Aomori Prefecture. http://english.kyodonews.jp/news/2011/04/83813.html

It is getting difficult to get current Japan news. Koydo News has been a good source headlines and links but it has discontinued its free page for earthquake and tsunami related coverage; its free page on nuclear crisis continues still. For couple of days, there are times when Drudge has no Japan related stories. When things are happening there, some of the good links have come from Drudge. Nekkei has been a source of some good headlines, but most details are behind the subscription screen. It is ironical that Japan is complaining about unfair coverage when so little new is available and the foreign residents in Japan complain about lack of news in non-Japanese languages

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300. Inject N2 into RX? Clear as mud

Your article says that they injected N2 into the reactor and the containment pressure went up as expected. That is as clear as mud. Maybe the press just considers the reactor as anything at the site. I think they have injected N2 into the drywell containment. The fact that it is holding pressure is a good sign that containment (drywell plus torus plus isolation pipe/valves) has integrity and no major breech. If they were injecting into the reactor vessel, they would have to do it on an ongoing basis and drywell pressure wouldn't go up right away unless there was a breech in the reactor vessel... something they wouldn't be happy about. I don't know about the press sensationalizing the event. I don't like the emphasis on reporting trace findings all over the world... there is still plenty of evidence of atom bomb testing all over the world. These small traces were very predictable and aren't really headline newsworthy. Japan seems most concerned about government restrictions on agriculture and seafood from Japan. Newspapers and press don't make trade restrictions... governments do. If TEPCO wants to get its side of the situation out, they could be a lot more forthcoming with statements about what they are doing and why. Rumors flourish in the absence of real news. If things aren't so bad, tell us why! Governments and disaster causing companies (remember how BP minimized leak estimates) never want to panic the public, but straightforward honesty is the best approach, I think. After this is over, Tepco is toast and probably this Prime Minister's government is, too. I agree with you... Thanks for the links... Spent fuel storage in Japan - That is a good thing for making all the other nuclear sites safer. Japan cannot afford to shutdown all of its nuclear plants immediately... and shutting them down would do little for making the spent fuel pools safer. An assessment of vulnerability to tsunamis should be done before restarting plants IMHO. They should have to either show that they are protected from any possible tsunami or have emergency power that is immune to one. JMHO

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301. 10 year decommission seems like a pipe dream

I know they can do construction in Asia a lot faster than in US, but 10 years to decommission the plants, including their spent fuel pools, seems like a pipe dream. Admittedly, there was no rush to do TMI plant, but the challenges in Japan are a lot greater. They have a long ways to go to get the rad levels down above those spent fuel pools to allow installing new cranes and working over the pools. I don't think there are any mobile cranes that could lift a spent fuel cask. Maybe Xxxxx has some insights on that. It doesn't seem possible, but neither does the Chinese nuclear plant building plan. I have trouble relating to getting that much done that fast. Regardless, thinking about decommissioning is a little premature... they haven't stabilized the situation yet. It was encouraging that they evacuated the site during the recent aftershock, but they didn't have to stop the injections of water. That implies that they have been upgrading their temporary makeshift injection systems... that is very good news. I think they are doing a lot of things that they aren't giving us a lot of details on. I saw just one story about them constructing new external cooling systems. I think the public, in Japan especially, would feel better if they knew what the emergency response team is working on. Just a thought... the public there has to be shell shocked with fear... between aftershocks, fear of tsunamis, and radiation concerns. The story may seem old and stale over here, but those people in Japan are still living the disaster. How will they cleanup those devastated homes in the evacuation zone that are contaminated? Did they ever get the highly contaminated bodies out? I don't think you can get how bad it is unless you are there. This is Katrina times (I don't know how much, at least 10).

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302. solar flares and power grids

Xxxxx, Xxxxx, Xxxxx, Xxxxx Thanks for keeping us updated.

Now I saw an article that suggests that many US nuclear plants (of similar older designs) with similarities to Fukushima Daiichi plant, may be vulnerable. Here is the article and a key snippet:

Most current reactors are of a similarly outdated design as the Fukushima reactors, where the cooling systems require electricity to operate, and huge amounts of spent radioactive fuel are housed on-site, requiring continuous cooling to prevent radioactive release.

edit to add this link: http://www.ritholtz.com/blog/2011/04/are-most-nuclear-power-plants-vulnerable/

The article goes on to state some circumstances of how there could be a major disruption to the electrical grids (around the globe) : For example, thru a major solar flare! Apparently, the earth's prtective magnetic field has been weakening and has a hole in it, which will make solar activity more damaging to electrical grids across the globe. I am not suggesting this is likely, but the very fact that a major grid disruption could put many nuclear plants in danger, is worrisome.

So, the question is, are there many (or most) existing US nuclear plants of similar design where they need external power to keep the reactors & spent fuel pools cooled?

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303. 3G plants are "passively safe"

So, the question is, are there many (or most) US nuclear plants of similar design where they need external power to keep the reactors & spent fuel pools cooled? ....

I suspect the answer is "yes", but I think Xxxxx will know better. I have been involved in the new construction of a number of plants in the last 10 years in China, Korea, Japan, Finland and France, which are mainly Westinghouse APR-1000/1400 or Areva EPRs, or the Korean/Chinese versions of these. These "3G" designs are "passively safe", meaning that they can sustain the worst possible accident (typically a major shearing of the largest reactor coolant pipe in the primary circuit, resulting in an immediate loss of forced cooling and instantaneous depressurization of the primary plant), without fuel damage and release of fission products to the environment, WITHOUT:

Direct operator action
The need for any AC power
Use of mechnaically- or electrically-operated equipment

These 3G plants use a combination of inherent design features, naturalo circulation, and in some cases flywheel-operated systems to survive the DBA (design basis accident).

I don't believe all, or even many, existing U.S. plants designed 30-40 years ago are designed to this standard.

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304. Thanks

That certainly is worrisome. I will wait for other experts to weigh in. At the same time, it may be time to start some serious "what if" scenario planning for the regulatory agencies. The what if scenarios should consider what happens to these plants with older designs and how to mitigate against the very major issues if something unthinkable were to happen (like losing all external power because of some natural calamity). JMHO

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305. Offsite power and onsite (emergency) power

I think that all commercial nuclear plants can survive a loss of offsite power. It is a very serious condition to lose offsite power, but emergency generators can operate emergency core and suppression pool cooling systems. These diesels could be reasonably expected to function reliably for weeks, if not months... provided diesel fuel was trucked in. There was no good reason for the spent fuel pools in Japan to end up in this condition. All nuclear plants I know of have diesel fire pumps. All they had to do was sometime in the first day or two dump a fire hose in the pool and turn it on... it would have kept the pools full. At the same time, I have always felt that onsite storage of large quantities if spent fuel is risky... perhaps more so at BWR's. As far as surviving a total loss of offsite power and all site emergency generators, I think almost all commercial plants would have core damage, including PWRs. There are battery and steam powered systems that would keep the reactor safe for a few hours, but after that batteries die and suppression pools overheat. In my opinion, there is nothing about the failures in Japan that are unique to Mark I, BWR 3/4 units. If they are obsolete because they couldn't handle a long term loss of all AC power, then so is every nuclear power station in the world... though I admit I don't know much about he Canadian or Russian designs. I doubt they would be better off, though. As far as evacuating a nuclear power plant, there is no currently operating nuclear plant that would not eventually suffer a core meltdown if the operating crew walked away from it (or otherwise couldn't do its job)

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306. news of upgrades are encouraging

It is encouraging to hear the upgrade to newer designed nuclear plants. There aren't any like what you describe in the US... how many exist in the world? I will stand by my statement that few commercial nuclear plants would survive a total, long term loss of AC power... maybe a few in Asia or France could. Perhaps, to say none could is incorrect. It isn't just 40 year old GE BWR's, though.

The reason we are talking about Japan is that tsunami destroyed the grid and all 14 onsite emergency generators... almost all of the plants systems went down at once. Shortly thereafter, almost everyone at the site left. No US plant could survive that.

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307. re-racking

My concern about Japan is the amount of spent fuel that appears to be stored on site. In a 2010 TEPCO report they outlined their plans to "re-rack" spent fuel in order to store more on site. The options are limited when there is no place for long term storage.

The problem I see with the re-racking plan centers on the amount of water there is in a spent fuel pool. Increasing the heat load in the pool will require increasing the heat removal capacity of the sytstem. A kidney-loop that circulated a thousand gallons per minute to cool a certain amount of fuel could fail sooner during a loss of power event.

There would be increased evaporation and decreased time.

The second area of concern for me centers on Xxxx's observation "what if the site becomes uninhabitable"

The risk in this case would span the entire fuel inventory.

Is there a regulation which govens the ratio of heat to gallons in a spent fuel pool? Without AC power, this ratio would be critical.

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308. Link to a public record of TEPCO spent fuel program

There is a public record of TEPCO's spent fuel program here:

http://criepi.denken.or.jp/result/event/seminar/2010/issf/pdf/6-1_powerpoint.pdf

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310. Install high density racks or shut down

Many plants in the US, including the plant I worked at, have installed high density storage racks in their spent fuel pools. It was that or shutdown... now fuel casks offer another option. These replacement racks increased the boron concentrations in the racks to allow packing more spent fuel into the pools in a tighter configuration. They did not require upgrading the cooling system. Most of the heat load on the pool comes from recently deposited fuel and the hot fuel removed from the core during refueling. I saw one report that one of the Units in Japan was refueling and the core had been offloaded into the fuel pool. This is sometimes done to expedite shuffling the fuel locations in the core or if repairs were being made to reactor internals. This configuration puts maximum cooling demand on the fuel pool cooling system. Maybe that is the one the US thought was dry. During refueling, we usually ran both loops of fuel pool cooling... only one was normally required during operation. The backup was RHR, which could be configured to cool the pool. About those high density racks... they required good water quality... turns out that they degraded faster when silica was high... can you imagine if the roof of the building is laying in the pool or they are open to the dusty outside environment... and the fuel pool demineralizers/cleanup system has been off since the crisis started with no hope of getting it back soon. There is not a lot of analysis for spent fuel pools in these conditions... they are beyond their design basis. These pools may have done better than some US fuel pools... I don't think that high density storage racks would have helped, but that is just a guess... it is more of a nuclear engineer's call, not my degree. I'm familiar with the equipment, not all of their design basis.

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311. More on spent fuel storage options

More on fuel storage options... http://allthingsnuclear.org/post/3991373119/dry-cask-storage-vs-spent-fuel-pools

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312. a single fire hose

As the pools in Japan heated up due to the loss of fuel pool cooling, evaporation from the pool increased... water level dropped without any makeup water... when the spent fuel was uncovered, temperatures of the cladding rises rapidly boiling off remaining water... fuel and racks fail. It is my belief that a single fire hose adds sufficient water to keep the fuel pool full avoiding any pool boiling and fuel failure. That is what our emergency procedures said anyway... The worst case accident at a storage pool is that the fuel would melt to an extent that the boron in the storage racks would be insufficient to prevent a localized critical chain reaction. This could generate sufficient heat to melt through the pool liner or explode (hydrogen or just rapidly expanding steam bubble). In BWR spent fuel pools, there is no boron in the pool water... only in the racks. It is the excess moderation

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313. edit due to I-pad

Sorry, using the "less than" sign causes problems with my post. My iPad can't edit posts, o I am stuck with depleting again) ... It is the excess moderation (keff less than 1.0 in the rack design and the fuel bundle placement that prevents the spent fuel pool from going critical... or even a localized critical. (I doubt that these racks were designed to carry the weight of the building roof.) That is why I have been so concerned about the fuel pools. If a pool liner is damaged so that you can't keep water in it... if enough of the fuel melts... things could get a whole lt worse than they are now. To get the radiation levels down above the pools, they will have to install a cooling system. That will also greatly reduce the need for makeup water. The pools are normally about 90-100 degF. They will have to get a cover over the pool. They will have to remove non-metallic debre from the pool. They will have to install filters and demineralizers in the pool. If the fuel has been badly compromised, these will have to be very well designed systems, because they will themselves become highly radioactive very quickly. Even then, rad levels could be high due to failed fuel... They should analyze their current racks to see how they will holdup to current conditions. I'm sure some pictures of the pool and it's contents would be very helpful.

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314. gate seals

It is my understanding (which could easily be wrong) that the gate seals which allow access to the fuel pool, are inflated with air to create a watertight barrier when the gate is not open. I read somewhere that the pneumatic circuit was powered on a different circuit than the emergency back up. Could it be possible that some pool water leaked from the un-inflated gate seals? If so, maybe the situation has been improved.

There is an enormous amount of water in the fuel pool, but each additional rack will displace more of the water while increasing the heat load.

The only cooling system I could imagine would either need Freon compressors or huge ambient-dependant heat exchangers driven by large fans. Either way, it would seem that the emergency cooling requirements would be difficult to achieve without some AC power right away.

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315. yes it would increase the heat load

Xxxx, yes, adding more fuel to the pool would increase the heat load, but our system was evaluated to have sufficient capacity for the high density racks. You are right that the margin was reduced, though. Gate seals are designed so that there is not a lot of leakage when they are uninflated. I agree that they are not water tight. There is some good stuff at his site below on the damage to fuel pools. One plant has the refueling bridge laying down on the pool. One of our analyzed accidents was a rod drop accident... a pretty severe event, one that would certainly have drawn a NRC inspection team... this is like infinitely worse. It is my understanding that at least one external AC power transmission line has been run to he plant. I agree that they need it to install new cooling systems. I agree that atmospheric or "Freon-like" systems would make the most sense. At least at some of the units, existing C/U and FP cooling has been destroyed. The fuel pool is described as concrete in several places. They could not maintain adequate water chemistry in the fuel pool if it were concrete. There is a stainless steel liner... a sand space with drains for leak detection... then concrete, a lot of it. The concrete is load bearing... the liner is the water retaining boundary. It would be difficult to keep water in the pool if the liner had a large breech. The fact that a fire truck hose is keeping the fuel covered, and I don't think they re continuously spraying, is a good sign. If fuel was uncovered, you would see a big steam cloud if you sprayed water on molten fuel cladding.

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316. Fukushima Daiichi reactor 3 and 4 damage analyses

In-depth technical analyses here: http://bigdustup.blogspot.com/2011/03/fukushima-daiichi-reactor-number-3-and.html

edit: some of this material will seem familiar to anyone who has read this thread.

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317. devastation on top of those fuel pools

The devastation on top of those fuel pools is mind blowing, looking at the link I posted above. They are going to need a huge piece of equipment with "claws" to pick a lot of that stuff off the refuel floor. There is no way people will be able to get close enough to do it. I am sure that rad levels on the refuel deck have to be at least 1 rem/hr. I wonder if there is a way to build a lake around and over it? I am not smart enough to know if that is practical or not... or what the problems are in doing so. I don't see a success path for bringing the situation under control for a very long time unless somebody has a brilliant idea or many such ideas. Fixing the original systems or even rebuilding the existing systems does not seem possible under the current conditions.

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318. In one of the earlier reports

Xxxxx, in one of the earlier reports, pieces from fuel pools flew off after hydrogen explosion and were just burried in the ground.

"The document also suggests that fragments or particles of nuclear fuel from spent fuel pools above the reactors were blown “up to one mile from the units,” and that pieces of highly radioactive material fell between two units and had to be “bulldozed over,” presumably to protect workers at the site. The ejection of nuclear material, which may have occurred during one of the earlier hydrogen explosions, may indicate more extensive damage to the extremely radioactive pools than previously disclosed. "

http://www.nytimes.com/2011/04/06/world/asia/06nuclear.html?_r=3&hp

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319. are steam explosions possible?

What would happen if the melting fuel actually escaped the containment and reached the water table? It must be within 20 feet or so of ground level. I suspect that you would get lots of steam coming up somewhere. Would a steam explosion be possible?

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320. I hope we don't find out

If the fuel pool(s) were empty, the melting clad would generate a lot of hydrogen... and there would be a lot of damage. Some of the rods in bundles could have exploded (due to high temps expanding trapped gasses in the rods). Oh yes, this material would be very very radioactive. What will happen if a core melts into the ground and reaches ground water? I don't know. Could steam cause an explosion? Maybe... maybe the water would just cool the fuel. I don't know... I hope we don't find out. By the way, the Japanese evacuation zone is proving to be inadequate. They need to move non-essential people further away from the site.

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321. April 11th photo's

Some new photo's shot by a drone

http://www.dailymail.co.uk/news/article-1372589/First-clear-pictures-true-devastation-Fukushima-nuclear-plant-Japan-flies-unmanned-drone-stricken-reactor.html

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322. Yahoo has some new photo's too

edit: I cannot fix the links. These are small grainy pictures. They are here:

http://news.search.yahoo.com/search;_ylt=A2KJ3CRkSaNNxjoAN7bQtDMD;_ylu=X3oDMTEwaHFka2hqBHNlYwNpbWFnZQRjb2xvA2FjNAR2dGlkA1VTTjAxN18z

There are a few direct links below

This is the control station for the remote controlled excavating equipment
?x=400&y=299&q=85&sig=VsASWz8zJS7WihzNTJvANg--

This is a picture of an unmanned remote controlled excavator
?x=400&y=299&q=85&sig=oBk83f5g23PxfXuvcrs_8g--

More unmanned equipment
?x=400&y=299&q=85&sig=Oxx7SlaYz9SNX8alZyu2Bg--

A police officer in a protective suit

?x=400&y=293&q=85&sig=sxkXX9ZlLpjAgSvcJhftcg--

Tsunami waves hit the seawall

?x=279&y=345&q=85&sig=r9jQKxU7R.bhQE3f3toZUw--

Tsunami whirlpools
?x=400&y=260&q=85&sig=6MTgLlejSvklcj_sQolxqQ--

Various pictures of the grounds

?x=400&y=271&q=85&sig=YMIhRVGYG3bu87czDivpug--

?x=400&y=266&q=85&sig=geCWicVi6jgGnUNdMrU06A--

?x=400&y=299&q=85&sig=1aBmBJj4fWGhO78a3AjiQA--

?x=400&y=299&q=85&sig=iiO1PZFuPRE4IkgZ2TXgHA--

?x=400&y=271&q=85&sig=unE4bfm6buk9xiWzvwqbpw--

TEPCO officials meet the press

?x=400&y=269&q=85&sig=UPuDqNa97Z5mQAZ1xQ3j4A--

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323. How is contaminated water getting into the turbine building basement?

I am still wondering how large quantities of very contaminated water ended up in the turbine building basements. There are not supposed to be many leak pathes from the reactor building to the turbine building... not allowing that kind of flow rate. Is that water from a fuel pool? Is there a pool that won't hold water?xxxxxx They shouldn't be allowing people to go into the evacuation zone and track contamination when they come out. Normally, when a Unit shuts down for an outage (and that doesn't include uncovering the core), the core will cool off after a couple weeks and not require as much core cooling capacity. That is something to look forward to. I saw one report that they were going to use a camera equipped helicopter drone to explore the site... about time! Looking forward to seeing those pictures. I can't imagine any nuclear Units in Japan restarting until the earthquake risk drops. Even then, it will be tough political decision. Any plants found vulnerable to tsunami waves should have their protection upgraded first. This might mean higher tsunami walls... it might mean additional emergency diesels in hardened locations... both or more.

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324. 10,000 terabecquerels per hour

Now they tell us, "...the crippled Fukushima Daiichi nuclear plant had been releasing up to 10,000 terabecquerels of radioactive materials per hour at some point...," but now "...the release has since come down to under 1 terabecquerel per hour..."

http://english.kyodonews.jp/news/2011/04/84721.html

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325. A few links

Below are a few resource links if you have an ongoing interest.

California Specific Radiation monitoring - UC Berkley
http://www.nuc.berkeley.edu/UCBAirSampling

American Nuclear Society
http://www.ansatunlv.com/index.html
http://www.ansatunlv.com/links.html#japan (news links)

Community environmental monitoring program
http://cemp.dri.edu/cemp/
http://cemp.dri.edu/japan_response.html (Fukushima Radiation)

Health Physics Society (news)
http://www.facebook.com/board.php?uid=157387224301493

National US Radiation monitoring - EPA RadNet Laboratory Data
http://www.epa.gov/radiation/rert/radnet-sampling-data.html#milk

Magnitude order of radiation exposure
Edit: The chart was no longer at that address. I am not sure where it is. Here is a less useful one http://en.wikipedia.org/wiki/Radiation_poisoning

Also, see the homemade radiation chart at post #71 above

[divvy]

326. A few thoughts .... proximity perspective.

When they start trying to pump out that badly contaminated water from the turbine buildings, maybe they will learn more about where it is coming from... seems kind of important. Some reports say they think it is U2 reactor water... if it is, how is it getting out of the reactor and containment? how is it leaking to the turbine building from the reactor building? The reactor building used to be secondary containment... there shouldn't be a lot of leakage between the buildings. If there is a reactor breeched, how would one deal with that? I would fill the drywell (and suppression pool). If the drywell or suppression pool is breeched, too? I don't know... It would be pretty difficult to get humans close to make repairs due to the radiation. They have a really big problem if more highly radioactive water is being generated than they can cope with. Perhaps they should consider recycling it if they can't get it "shut off" at the source... pump it back into the Units that already have core damage. Sounds like the Chinese are frustrated about the lack of detailed news out of Japan, too. Normally, I would say that the upgrade to a level 7 is not particularly meaningful, but Tepco has not exactly been giving downbeat pronouncement... complained about journalists being too pessimistic or using scare tactics... the fact that there current assessment is that it is "as bad as it gets" is a little sobering... but true! There are several factors that make this situation very very bad - 1) the dense population of Japan with Tokyo only 75 miles away (not the boonies of Ukraine... 50,000 city was evacuated in Ukraine), 2) impact on 6 nuclear Units... most, but not all, US plants are 1 or 2 unit plants, and 3) the spent fuel storage pools and how to safely secure their contents. While hopefully the loss of life is far less than Chernobyl, I suspect that the financial cost of this accident will far exceed Chernobyl. I also suspect that it will also have a far more costly impact on the nuclear power industry all over the world. Here is a scary thought for you... would if this accident had happened in a small third world country that didn't have Japan's resources or their nuclear expertise?

[divvy]

327. Conservation of mass

Conservation of mass -- they should be able to tell how much water is evaporating from the fuel pools based on it's surface area and water temperature. They know about how much water they are putting into the pool. Is there a big mismatch indicating a big leak? They should know how much water they are pumping into each reactor vessel. They should be able to estimate how many pounds of steam they are venting off of the vessel to maintain constant pressure. Is there a big mismatch indicating a reactor vessel leak? If they are monitoring reactor and containment pressure, both staying close to the same pressure would also imply a big leak from the reactor vessel. In short, they should be able to assess the integrity of the vessels and containment. I think that they have already acknowledged that one Unit had a ruptured suppression pool. If so, they should try to lower the water level in the torus, so it stops leaking... if they can. This is important to understanding why the turbine buildings are filling with nasty water with high rads. Where is that water coming from and why? The external tanks they put this stuff into were not designed for high rad material... they aren't shielded. How will it affect ambient dose rates to workers? -- ps They should have emergency, standby generators brought onsite... or fire trucks standing by... they shouldn't be losing the capability to inject water following aftershocks. Come on!!!! The world is watching...

[divvy]

328. Radiation Chart

I reformatted the radiation chart in post 71 above

[divvy]

330. Ionizing radiation unit conversions

Ionizing radiation unit conversion here: http://en.wikipedia.org/wiki/Ionizing_radiation_units

To be used with the radiation chart above (information was culled from various sources). More later.

[Imagevision]

329. "Please do not go outside. Please stay indoors" those living within 100 miles your history

[divvy]

332. Damabe to #4 spent fuel pool and the Design Basis

Damage to #4 spent fuel pool confirmed http://english.kyodonews.jp/news/2011/04/85259.html

Nuclear power plants are designed to safely survive a design basis earthquake. That is not the same thing as saying it won't be damaged by it. There is a lot of non-Safety Related equipment in the plant required for normal operation of the plant that is not seismically qualified. Normal feedwater, much of the BWR's steam lines, etc etc are considered NSR and is not seismically qualified. None of the Radwaste System is Safety Related. A lot of this piping contains radioactive water. Safety Related is reserved for those systems necessary to shutdown the reactor and keep it in cold shutdown. The fuel pool cooling and cleanup system is not considered Safety Related. I would expect that any nuclear plant would require extensive inspection and major repairs after a severe earthquake.

See the thread starting at #270 above for some related information

[divvy]

333. Verifiable probe of the Fukushima Nuclear crisis

Commissioner calls for verifiable probe of Fukushima nuke crisis
By Masakatsu Ota
TOKYO, April 14, Kyodo

The vice chairman of the government's Japan Atomic Energy Commission emphasized this week that Japan should thoroughly investigate the nuclear crisis at the Fukushima Daiichi power plant in an internationally verifiable manner, possibly by involving experts from other countries to help guarantee the openness and transparency of the probe.

http://english.kyodonews.jp/news/2011/04/85324.html

[divvy]

334. anti-nuclear energy sentiment in Germany

Visiting Germany for 10 days, it's clear that the anti-nuclear energy sentiment is widespread. I'm seeing proposals in mainstream business papers about not just permanently shutting down the seven oldest reactors (which have already been turned off), but proceeding to phase out the other nine in a few years.

Unfortunately, the Green Party screamed bloody murder when Merkel decided to extend the lives of the old reactors. A few months later we get Fukushima, making Merkel look like a fool. What can she say at this point? "Don't worry, no earthquakes in Germany?" Forget that.

One issue is the Japanese model of leaving nuclear plant mangement to private utilities ... which have a nasty habit of lying.

Bottom line: Germany is serious about replacing nuclear with anything and everything else. "Desertec" is getting new attention.

[divvy]

335. Thats a pity

That's a pity, because with German engineering and labor quality, they could be in the vanguard in nuclear power technology development and sales worldwide.

[divvy]

336. serious loss of confidence

True. It probably won't happen as long as Fukushima is out of control and Japanese politicians pretend that things are not that serious; but afterwards we could see a renewed effort for safe use of nuclear energy with 3rd generation technology and better safety management.

The problem is that Fukushima is not in the Ukraine. This wasn't supposed to happen in an advanced industrial nation like Japan. So, new and expensive "fail safe" systems will be required with better ideas for plant management. This event has caused a serious loss of confidence ... with good reason IMHO.

[divvy]

337. Groundwater radiation level at nuke plant rises: TEPCO

Groundwater radiation level at nuke plant rises: TEPCO
TOKYO, April 15, Kyodo

The concentration levels of radioactive iodine and cesium in groundwater near the troubled Nos. 1 and 2 reactors at the Fukushima Daiichi nuclear power plant have increased up to several dozen times in one week, suggesting that toxic water has seeped from nearby reactor turbine buildings or elsewhere, Tokyo Electric Power Co. said Thursday.

The announcement came as the plant operator continued to grapple with pools of highly radioactive water found on the plant's premises, with the level of polluted water filling an underground trench edging up again after the company finished pumping out around 660 tons of water.

<snip>

A total of around 60,000 tons of contaminated water is believed to be flooding the basements of the Nos. 1 to 3 reactor turbine buildings as well as trenches connected to them, and the water is hampering work to restore the cooling functions of the reactors

story: http://english.kyodonews.jp/news/2011/04/85532.html

[nadinbrzezinski]

338. If it gets into the artesian system

that is worst than the worst nightmares

[divvy]

341. self delete

self delete

[divvy]

339. Where exactly is it coming from?

Where is the water coming from? You would think it has to be coming from somewhere that you are having to pump in a lot of water. Is one of the fuel pools requiring a lot more water to keep it cool? Is one of the reactors requiring a lot more water to keep it cool? Has one of the suppression pools drained? They can't store an infinite supply of this nasty water and it apparently is too radioactive to discharge to the ocean without some treatment. The best solution requires that you understand why the water is being created. A less good temporary solution would be to run the water through a demineralizer or reverse osmosis (or similar) filters and discharge the water... or better yet use that water to pump into fuel pools and-or reactors. I think that there are maybe some things they could do about a leaking reactor and containment... I am at a loss about what to do about a fuel pool with a large leak. xxxxxxx The long term impact of this event on the industry depends on how it is ultimately resolved. I think that one outcome should be to reconsider how safe it is to put these plants in countries without the nuclear oversight and expertise to handle emergencies. This event would have taxed any country, but do you want nuclear plants in countries like Iran, South Africa, Mexico, Iraq, Pakistan, etc etc? Even China... are they ready to operate a huge fleet of plants? Running these plants is hard... maybe not so hard at newer plants like he ones Chang works with... but still, they require a lot of engineering, training, regulations to insure safety, etc etc.

[divvy]

340. That is over 4 1/2 million gallons under reactor 2 alone

Below are quotes from one of the article posted above. It was just updated.

The pools of contaminated water are believed to be a side effect of TEPCO's emergency efforts to continue injecting water into the reactors and their spent nuclear fuel pools from outside to cool them down.

<snip>

Hidehiko Nishiyama, the agency's spokesman, told a press conference Thursday morning that the rise in the water level is likely linked to the continued injection of water into the No. 2 reactor core, which is necessary to prevent the nuclear fuel inside from overheating.

<snip>

The water in and around the No. 2 reactor turbine building is believed to contain higher concentrations of radioactive substances than other contaminated water found at the site, and is believed to originate from the No. 2 reactor's core, where fuel rods have partially melted.

The story is here:

http://english.kyodonews.jp/news/2011/04/85532.html

The article talks about water in different locations. The first reference is 660 tons. At 8.6 pounds per gallon, that would be about 153,500 gallons.

It also says there are about 20,000 tons of highly radiated water under reactor #2 which is about 4,651,162 gallons of water. (more than 4 1/2 million !)

Maybe part of the fuel has melted through the containment?

[divvy]

342. Melted nuclear fule likely settled at the bottom of the crippled reactors

Melted nuclear fuel likely settled at bottom of crippled reactors
TOKYO, April 15, Kyodo

Nuclear fuel inside the crippled reactors at the Fukushima Daiichi power plant has partially melted and settled in granular form at the bottom of pressure vessels, according to an analysis by the Atomic Energy Society of Japan made public by Friday.

<snip>

The academic body's panel on nuclear energy safety has said the melted fuel at the Nos. 1 to 3 reactors has been kept at a relatively low temperature, discounting the possibility that a large amount of melted fuel has already built up at the bottom of the reactor vessels given the temperature readings there.

A large buildup of melted nuclear fuel could transform into a molten mass so hot that it could damage the critical containers and eventually leak huge amounts of radioactive materials.

The panel has also said that the fuel grains with a diameter of between several millimeters and 1 centimeter are believed to have settled evenly at the bottom of the vessels, leaving almost no possibility of a nuclear chain reaction called ''recriticality.''

<snip>

More here http://english.kyodonews.jp/news/2011/04/85725.html

[divvy]

343. "settled fuel"? what a joke ! "recriticality" not likely

The description of fuel pellets spread uniformly over the bottom of the reactor vessel? What a joke! That isn't even possible. The bottom of the vessel is made up of standpipes that have the control rod drives extending up into the core... or at least they used to. If the fuel melted, these control rod drives and control rods and control rod channels make the bottom of the vessel look like a molten junk yard setting on top of a bunch of pipe stubs. This Japanese description of a melted core bears no relationship to what was seen inside the TMI reactor. Good lord... they know not what they say. We won't know for decades what those cores look like, but I am absolutely certain they won't look anything like that description. I wouldn't say recriticality is very likely either, but not for the reasons described in this article. I would hope that lots of boron has been injected into the vessels... the fuel pools, too, for that matter. I think that where recriticality can be the most dangerous is where you remove moderation and cooling and then reintroduce it... say you let the core drain of water... the core configuration changes from melting (e.g., control rods melt away)... then you introduce water moderator that can increase power. This, I think, is when recriticality risk was the highest. The same could have happened in the fuel pool. It didn't... that is good thing... If that happened, you would recognize it by the explosion.

edit: add bolding

[divvy]

345. Not a mushroom cloud, more like Chernobyl

But it wouldn't be mushroom cloud... it would look like Chernobyl, I think. Even more than it already does... I am almost as impressed with the government statement that they will have the plant stabilized by June or July... how meaningful is that if they are clueless how they are going to accomplish it? I can see why the Japanese population isn't happy with what they are hearing from TEPCO and government. Hopefully, I'm being too harsh... I am surprised how little coverage the disaster is getting in the Sates... apparently, the US media grows weary of reporting the same bad news every night. Then again, the Japanese stock market hasn't taken it very seriously either IMHO. It is well above 2010 low... is this really going to be a better year for Japanese companies than last year? Sure not for the Japanese people...

[Yo_Mama]

344. They're still not sure

Originally there was a lot of water from the tsunami.

They have started pumping out the basement and trench water from reactor 2, but they aren't gaining on it very much. So one theory is that the water is seeping out of the reactor (and given contamination levels, some must be), but they also blocked the outflow to the sea; water in the saturated ground may be leaking into these lower places through cracks in the concrete.

What they seem to be doing now is to keep pumping and keep testing, because that's going to tell them whether this is old contamination (from explosions, etc) or current very hot contamination eventually.

They did test the groundwater in places after they blocked the outflow to the sea, and they found some relatively hot water.

They also tested the water in the spent fuel pool on 4, and the reported contamination levels aren't that bad.

So if they keep pumping and it keeps coming, eventually they will have to figure out another plan.

Also they had sampled some water lower down in one of the trenches and it wasn't that hot, so they knew that some of the water was left over from the tsunami which flooded the entire site.

They are having about 1 aftershock every other day. In the last ten days they've had two at around mag 7 and multiple 6s. I would imagine that the concrete infrastructure of the plant site is still degenerating.

[divvy]

346. Fukushima Daiichi workers face radiation limit

KITAKAMI, Japan — The thinning ranks of men struggling to tame Japan's nuclear emergency are invoking the spirit of the samurai as they ignore personal radiation limits in their battle to avert disaster.

Some are so determined to push on with a task they see as vital to saving Japan they are leaving their dosimetres at home so bosses do not know the true level of their exposure to radiation at the crippled plant.

More here:

http://news.asiaone.com/News/Latest%2BNews/Asia/Story/A1Story20110414-273574.html

[divvy]

347. Japan Atomic Forum -- Status of Fukushima Nuclear Power Plants

Xxxx, did you have time to read this? I thought you might be interested in it.

http://www.jaif.or.jp/english/news_images/pdf/ENGNEWS01_1302693266P.pdf

EDIT: There are 6 pages in the above report. It is easy to miss the last 4 due to a large vacant space at the bottom of page 2

[divvy]

348. Thanks I do like the chart

Thanks, Xxxxx, I do like that chart. It is interesting that the Unit they suspect of a leaking RX vessel and containment (where all the water may be coming from), U2, is not the Unit with most core damage or most extensive damage to building from H2 explosions. It makes one wonder what happened to U2. It is good to see that Units 5,6 seem to not have suffered much damage. I am glad to hear that AC power was restored and fuel pool cooling is on. Great! Back to U1, though... it is not good that the temperature is not declining much. The chart is pretty vague about what they are doing to control pressure in the RX vessels. There is a reference to a low pressure being created in vessels (condensing steam can do that). The discussion about the RX vessels 2 and 3 losing their leak tightness because of low pressure? Low pressure? Vacuum? I am not sure what they are talking about and how it could cause a lack of leak tightness. Since they think there are no cracks or holes in them, I guess they think some seals or valve packings may have failed if exposed to vacuum. There is a big leak, so maybe in the control rod drives and-or nuclear radiation monitors penetrating the bottom of the vessel. U4 fuel pool is a problem. The hot core from the vessel is in the pool. That is why its RX was badly destroyed from hydrogen. There is a lot of damaged fuel in that pool. I would fear that the leaking water might be coming from it. A water sample from this pool would be a good source of info.

[divvy]

349. U.S. offers unmanned chopper to help remove Fukushima spent fuel

U.S. offers unmanned chopper to help remove Fukushima spent fuel
TOKYO, April 17, Kyodo

The U.S. government has told Japan that it can use a U.S. unmanned cargo transport helicopter to set up cranes to remove spent fuel rods from storage pools at the crippled Fukushima nuclear power plant, Japanese and U.S. sources close to the matter said Saturday.

The K-MAX helicopter, developed jointly by Lockheed Martin Corp. and KAMAN Aerospace Group of the United States, is being considered to set up the huge cranes.

<snip>

TEPCO has been cooling down the spent fuel storage pools on the fifth floor of the reactor buildings by pumping water using a truck-mounted concrete pump.

Spent nuclear fuel is usually transported away from nuclear plants inside steel casks after being cooled in storage pools for a few years.

Since the original fuel transportation equipment at the Fukushima plant's reactor buildings was damaged by hydrogen explosions following the March 11 quake and tsunami, TEPCO is considering employing a huge crane to lift casks into the storage pools so that spent fuel rods can be placed in them.

More here: http://english.kyodonews.jp/news/2011/04/85954.html

[divvy]

350. TEPCO plan to end the Fukushima Nuclear crisis

TOKYO, April 17

Gist of TEPCO plan to end Fukushima nuke crisis http://english.kyodonews.jp/news/2011/04/86072.html

[divvy]

351. TEPCO plan to achieve cold shutdown

TEPCO aims to achieve 'cold shutdown' for reactors in 6-9 months http://english.kyodonews.jp/news/2011/04/86054.html

Edit: Confirming Nikkei story http://e.nikkei.com/e/fr/tnks/Nni20110417D17JF297.htm

[divvy]

352. TEPCO to use robots to examine the reactor buildings today

TOKYO, April 17 TEPCO to use robots to examine reactor building conditions http://english.kyodonews.jp/news/2011/04/85981.html

[divvy]

354. I am glad to see the plan includes what we have talked about

I am glad that we can finally see a plan for ending the crisis. It includes many of the things we have talked about. I was skeptical from the very beginning that they could restore RHR shutdown cooling at the heavily damaged plants. The external cooling systems seem like the best path to cold shutdown. I am a little stunned that it will take 6-9 months. They will have to design a lot of radiation shielding for the systems. I would have thought that under the circumstances, they could do it faster than 6-9 mos. I see where they plan to flood the drywell containments. Back when the accident first happened, I said that our procedures said that if you couldn't maintain core coverage, then flood the containments. Various accounts suggest that they may have tried that with one Unit... but now (finally) I guess they will flood all 3 containments. It should make it easier to keep the core covered and provide insurance that the containment integrity is maintained. They are talking a lot about fuel pool cooling, but they should at least be thinking about how to cleanup the water in the spent fuel pools. Clean water in the pools improves visibility in the pool (important for all fuel pool work)... may be important to rack integrity... and will reduce dose rates over the pools. The first step to cleaning the water up in the pools would be to pluck all the debris out of the pool (e.g., roof of one RX building). In at least one unit, the refueling bridge seems to be precariously positIoned over the pool. It will be hard to do work over or in the pools with the high dose rates. You certainly will not be able remove the spent fuel to permanent storage without first cleaning up the pools. This most recent batch of news releases seem to be doing a better job of transparency. We at least know more about what they are working on.

EDIT: referring to the four news posts directly above this one. See also post #347

[defendandprotect]

355. Keep this thread kicked -- !!

[defendandprotect]

356. Too late to Rec -- where's this thread been?

[divvy]

357. Spent fuel pool photo shot from the top of the Putzmeister

Photo taken from a truck-mounted (Putzmeister) concrete pump on April 14, 2011, shows the spent nuclear fuel pool of the No. 3 reactor at the Fukushima Daiichi nuclear plant.

[divvy]

358. That looks bad and the water is steaming

That looks bad, and the water is steaming.

And isn't it #4 that's got the worst spent-fuel problem?

[divvy]

359. It does look bad

Xxxx, there will be considerable vapor given off all the fuel pools until cooling systems are added. The water added to the pool is keeping the pool from emptying... and it keeps the water from boiling... but I suspect the temperature is closer to 200 degF than the normal 100degF. There is a lot of vapor given off by hot water. Yes, the debris is awful. Yes, U4 fuel pool has the hot core from the reactor vessel in it... and requires the most cooling to prevent boiling. This vapor given off at these elevated temps probably has a lot of Iodine gas in it. To get the dose rate down above the pool, the water needs to be cooled and cleaned up. All this loose metal etc over the top of the pool is dangerous. Dropping things onto spent fuel is not a good thing... it does look bad!

[divvy]

360. #4 fuel pool is probably getting the most water

The water in the bottom of the #4 RX Building is probably spillage from spraying water at the spent fuel pool. Water missing the pool would spill through equipment hatches, stairwells, etc etc. The various floors of the RX building are not water tight. Water sprayed onto the top floor would eventually work it's way to the basement... much like you letting a bath tub overflow in an upstairs bathroom. I would think that #4 RX Building is getting sprayed the most, because of the hot fuel in it

[proud patriot]

361. I viewed all the pictures of Biker Girl's trips close to Chernobyl

one of the things mentioned was the high concentrations of rads indoors in pockets.
I wonder just how useful the suggestions of staying indoors is :-(

[divvy]

362. Radiation inside 1 and 3 is up to 57 millisieverts

Radiation inside Nos. 1, 3 reactor buildings up to 57 millisieverts
TOKYO, April 18, Kyodo

The radiation level inside the Nos. 1 and 3 reactor buildings at the crippled Fukushima Daiichi nuclear power plant was up to about 57 millisieverts per hour as of Sunday, the government's nuclear safety agency said Monday, acknowledging that it is a level that puts time constraints on any restoration work that must be done there.

Story: http://english.kyodonews.jp/news/2011/04/86266.html

Note: for context, find the home-made radiation chart above at post 328. I believe the limit for plant workers is 50 millisieverts per year

[divvy]

363. Some work will need to be done by robots

As time goes by, more work will need to be done with robots.







Story here: http://www.bbc.co.uk/news/technology-13114310

[divvy]

364. TEPCO starts moving highly radioactive water to storage facility

TEPCO starts moving highly radioactive water to storage facility

Tuesday 19th April, 03:27 PM JST
FUKUSHIMA —

The operator of the crippled Fukushima Daiichi nuclear power plant on Tuesday started moving highly radioactive water from the No. 2 reactor turbine building to another facility at the site as part of efforts to enable engineers to engage in work to restore key cooling functions of the troubled reactors.
Workers are struggling to remove some 25,000 tons of deadly water in and around the No. 2 turbine building, which has an extremely high level of radiation exceeding 1,000 millisieverts per hour. The total amount of contaminated water accumulating in the plant’s premises is estimated to be a little less than 70,000 tons.

<snip>

Story here: http://japantoday.com/category/national/view/tepco-starts-moving-highly-radioactive-water-to-storage-facility

Note: for context, find the home-made radiation chart above at post 328 if it does not post below.

EDIT: Remember that radiation exposure is cumulative (additive).

[divvy]

365. air pressure supported structure?

I would think that the easiest and quickest way to cover those reactor buildings would be to install an air pressure supported structure, like what you see installed on some sports stadiums. Snow recently collapsed such a structure in Minneapolis (Viking's stadium). People aren't going to be able to work above the pool for a long time. I would think that stopping the containment leak from U2 would be high priority. It really doesn't do a lot of good to pump out those turbine building basements if the water is leaking into the volume at a high rate... repairing the leak will probably be difficult, but the first step is identifying it. They need the turbine building basement emptied to restore RHR Service Water Pumps, I think. I remain skeptical that they will get RHR back on U-1,2,3. The robots being thwarted with high humidity fogging implies that there is very hot water leaking into the areas. That could be from the fuel pools or reactors or from the U2 suppression pool. My guess, since it is present in all 3 buildings, is the fuel pools.

[divvy]

366. Nuclear plant workers at risk of depression, death from overwork: doctor

Nuclear plant workers at risk of depression, death from overwork: doctor
Wednesday 20th April, 11:40 AM JST

FUKUSHIMA —

Tokyo Electric Power Co workers engaged in efforts to stabilize the crisis-hit Fukushima Daiichi nuclear plant are at risk of depression or death from overwork, a doctor who recently saw them said Wednesday.

Story: http://japantoday.com/category/national/view/nuclear-plant-workers-at-risk-of-depression-death-from-overwork-doctor


I had read that the heroes were sleeping at work... on the floor in hallways. I am surprised that most aren't dosed out and replaced with new workers on a fairly frequent basis. How can it be that these heroes are being treated this way? Good grief, these workers are risking their lives to save their country... and TEPCO can't find even an air mattress for them to sleep on? ... can't get them some catered food? Medical assistance?

[divvy]

367. Tsunami proofing a nuclear plant

Tsunami proofing a nuclear plant - The reason that the tsunami in Japan was so devastating was quite simply that it knocked out all offsite power and all of the onsite emergency diesel generators. To tsunami-proof a plant, you don't need to stop the wave in its tracks... you only need to provide a tsunami-proof power supply to existing emergency cooling systems and battery chargers... That could be emergency diesel generators located high above the zone of vulnerability and underground cables feeding the plant... and reviewing whether any safety system components need to be positioned above flooding concern or in water proof vaults. RHR Service Water and regular Service Water might need to be hardened. The point is that tsunami-proofing a plant isn't totally impractical. Nuclear power plants need to look at all events that might disable all their emergency generators... that needs to be added to their design basis, because it hasn't in the past been considered a credible event... now we know better. Nuclear plants should also consider upgrading HPCI and RCIC to be self-sufficient to the extent that steam could not only provide the pumping turbine, but also the DC power to run the system. HPCI or RCIC could have potentially saved the cores in Japan, but without any AC power to charge batteries, the systems died in 4-8 hours. These 4-8 hours worth of batteries are huge (fill multiple rooms)... instead of just adding more and more batteries, secure the battery chargers by eliminating their total dependency on emergency diesels to keep the batteries charged. The HPCI and RCIC turbines could be designed to turn a pump and a generator to feed battery chargers. There are a lot of lessons learned from the Japanese events. There is obviously a lot of sole searching needed for spent fuel pools. Safer, long term storage needs to be found. An automatic makeup water supply should be considered. More than anything, a greater understanding of the risks are needed. The Japanese plant personnel found themselves in a condition that was beyond what they had procedures for. They should have put a running fire hose into each pool and I think they could have avoided a lot of problems (e.g., some or all of the H2 explosions). Most plants have redundant diesel driven fire pumps. I don't think they were flooded. Nuclear plants need to review their emergency facilities for how hardened they are... and alternative sites... and communication systems. You need to have confidence that your emergency action plans will be implemented... even in a disaster.

[divvy]

368. TEPCO admits fuel could be melting at nuke plant

TEPCO admits fuel could be melting at nuke plant
Thursday 21st April, 07:10 AM JST

TOKYO —

An official at Tokyo Electric Power Co, the operator of the crippled Fukushima Daiichi nuclear power plant, admitted Wednesday that fuel of the plant’s No. 1 reactor could be melting.

At a press conference, TEPCO official Junichi Matsumoto said, ‘‘I’m not saying with certainty that (the fuel) has never melted,’’ while noting that the utility has not been able to confirm the condition of the reactor’s core.

Describing the possible meltdown, Matsumoto said it can be compared to a state in which molten fuel accumulates like lava, or a state in which fuel rods get exposed after their tubes were broken. TEPCO considers such states as a meltdown, he said.

Story http://japantoday.com/category/national/view/tepco-admits-fuel-could-be-melting-at-nuke-plant

[divvy]

369. The melted fuel discussion is an academic one.

The discussion of whether fuel has melted or not is really an academic one and it is not clear what is meant. The fuel is definitely badly damaged at U1-3. There is badly damaged and perhaps melted cladding. The evidence is H2 gas generation from the burning of the clad, the high dose rates near containment and coolant water, the Iodine and other radioactive nuclides in the gases vented from the site and recorded all over the world. It will probably not be known for a decade or more just how bad the fuel pellets are melted. At TMI, it was a decade before pictures of the fuel assemblies were available. My guess is that there is a lot of damage to all 5 cores in the vessels and U4's in its fuel pool. Whether or not the fuel pellets have melted or not? Is it that important to know? The main thing is that the fuel is still in the reactor vessels or pool and those structures have their structural integrity. If I was a reporter, I would be asking TEPCO what they are doing to make their workers' lives more bearable at the site... what are they doing to assess the leak from U2's containment and stop it... are they going to be able to use the robots to explore the plants... what are they planning to reduce to radiation leakage from the site... what is Japan doing to replace lost generation from the nuclear plants... when will some of them restart - and what evaluations have they done to allow restarting... when will the supply interruptions for Japanese car parts and electronic components ease? There are lots of questions more important than whether or not the fuel pellets have melted.

[divvy]

370. Tepco is hoping to recycle water into the reactor core

Kan to make 20-km no-entry zone binding

<snip>

Meanwhile, work to pump out dangerous radioactive water from the plant's reactor 2 turbine building continued Wednesday, and Tokyo Electric Power Co. said the level of contaminated water filling up an underground tunnel connected to the building finally started dropping.

But the water level of another trench connected to the reactor 3 turbine building is edging up, the Nuclear and Industrial Safety Agency said.

<snip>

Tepco plans to create by June a system that would clean up the stored water to some extent. It is also hoping to eventually recycle some of the water so it can be injected into the reactor core.

Story: http://search.japantimes.co.jp/member/member.html?mode=getarticle&file=nn20110421a2.html

Thanks to AsahinaKimi