# Are the Japanese Nuclear plants melting down?



## Capt Worley PE (Mar 11, 2011)

Gosh, she sure is a dolt:



> WASHINGTON (Reuters) – The United States has transported coolant to a Japanese nuclear plant affected by a massive earthquake and will continue to assist Japan, Secretary of State Hillary Clinton said on Friday.
> "We just had our Air Force assets in Japan transport some really important coolant to one of the nuclear plants," Clinton said at a meeting of the President's Export Council.
> 
> "You know Japan is very reliant on nuclear power and they have very high engineering standards but one of their plants came under a lot of stress with the earthquake and didn't have enough coolant," Clinton said.


http://news.yahoo.com/s/nm/20110311/pl_nm/...nuclear_clinton


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## wilheldp_PE (Mar 11, 2011)

She better ship them some pneumatic fluid too.


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## Dexman PE (Mar 11, 2011)

Blinker fluid?


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## humner (Mar 11, 2011)

I heard that they are lowering it down with 50' of flight line


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## humner (Mar 11, 2011)

our adapters don't fit theirs so we are including thread streachers and to cut down on noise vibration muffler bearings are being installed.


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## Road Guy (Mar 11, 2011)

I thought it was all ball bearings these days?


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## Capt Worley PE (Mar 11, 2011)

She's still trying to find a gallon of prop wash.


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## humner (Mar 11, 2011)

Capt Worley PE said:


> She's still trying to find a gallon of prop wash.


I don't know how many would get this one, but I think the prop wash is next to the "red chit oil"


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## Flyer_PE (Mar 11, 2011)

On a serious note, Unless their plant design is totally odd (which I know it isn't), I can't imagine what they could possibly need to keep a reactor safely in hot/cold shutdown.


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## snickerd3 (Mar 11, 2011)

Flyer_PE said:


> On a serious note, Unless their plant design is totally odd (which I know it isn't), I can't imagine what they could possibly need to keep a reactor safely in hot/cold shutdown.


I was sort of wondering the same thing.


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## Capt Worley PE (Mar 11, 2011)

me too.


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## FusionWhite (Mar 11, 2011)

Im no expert in nuclear power plants, but a couple guys here at the office come from nuclear backgrounds and said there could be a couple of problems. One is the reactor core is no longer pressurized and no longer circulating the coolant which is causing the water in the core to boil. As the water boils off the core becomes exposed and melts. The other problem could be that the secondary (the steam generating) loop is not circulating water and thus not cooling the primary coolant.

As the primary coolant boils away in theory they could simply dump more water in, but if there coolant pumps are not functioning then its only a matter of time before they boil away all the water in the core. The guy here at the office said the "coolant" we may have shipped them may be some sort of neutron moderator (heavy water or boric acid are often used) which would both cool the core and slow down the generation of heat in the core by absorbing neutrons that keep the fission reaction going.

Again, thats second hand information from a couple of former nuclear guys in my office, Im by no means familiar enough with nuclear power plant operation to say if they're right or wrong so please feel free to call bullshit or chime in otherwise.


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## Flyer_PE (Mar 11, 2011)

What they are describing is a Loss of Coolant Accident (LOCA). All of those systems are both electrically and mechanically redundant. One of the things I'm not sure of is whether they have the boron injection systems that we have here. Basically, for boiling water reactors, there's a tank of boric acid isolated from the reactor by squib valves. If the rods don't go in, blow the valves and start the positive displacement pumps. Then call the concrete tucks because you just trashed the unit.

The thing is, they have an ocean right there and if you're desperate to cool a core, you stop caring about water chemistry pretty damn quick.


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## Road Guy (Mar 11, 2011)

part of the GA / FL / Alabama water wars is that the river (in question) serves to cool a nuclear reactor in Alabama somewhere?


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## engineergurl (Mar 11, 2011)

Road Guy said:


> part of the GA / FL / Alabama water wars is that the river (in question) serves to cool a nuclear reactor in Alabama somewhere?


Really... I hadn't heard that one on the news... STOP TAKING OUR WATER UP THERE! lol


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## navyasw02 (Mar 11, 2011)

FusionWhite said:


> Im no expert in nuclear power plants, but a couple guys here at the office come from nuclear backgrounds and said there could be a couple of problems. One is the reactor core is no longer pressurized and no longer circulating the coolant which is causing the water in the core to boil. As the water boils off the core becomes exposed and melts. The other problem could be that the secondary (the steam generating) loop is not circulating water and thus not cooling the primary coolant.
> As the primary coolant boils away in theory they could simply dump more water in, but if there coolant pumps are not functioning then its only a matter of time before they boil away all the water in the core. The guy here at the office said the "coolant" we may have shipped them may be some sort of neutron moderator (heavy water or boric acid are often used) which would both cool the core and slow down the generation of heat in the core by absorbing neutrons that keep the fission reaction going.
> 
> Again, thats second hand information from a couple of former nuclear guys in my office, Im by no means familiar enough with nuclear power plant operation to say if they're right or wrong so please feel free to call bullshit or chime in otherwise.


I brain dumped a lot of my nuclear knowledge as I crossed the brow of my submarine for the last time, but that's pretty accurate. I spent a lot of time shutdown/cooldown and we operated the plant like this a lot when we were in the shipyards getting overhauled. I just dont see what kind of "coolant" they'd be using that needed the Air Force to bring in unless it's a non water based reactor (ie. liquid sodium).


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## MadDawg (Mar 11, 2011)

Road Guy said:


> part of the GA / FL / Alabama water wars is that the river (in question) serves to cool a nuclear reactor in Alabama somewhere?



http://en.wikipedia.org/wiki/Joseph_M._Far...erating_Station


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## engineergurl (Mar 11, 2011)

MadDawg said:


> Road Guy said:
> 
> 
> > part of the GA / FL / Alabama water wars is that the river (in question) serves to cool a nuclear reactor in Alabama somewhere?
> ...



Yeah, thats near my house... dont steal my water... HA HA HA


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## Flyer_PE (Mar 12, 2011)

I just did a little reading and it appears that two of the nuclear units over there are in a real-deal Station Blackout (All Diesels failed - all you got is batteries). The stations are designed to withstand that but they will likely be venting some contaminated steam. The risk of a melt-down is minimal but that won't stop the media from screaming it from the roof-tops. The article I read indicated they are trying to get portable diesels in place for temporary power.


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## wilheldp_PE (Mar 12, 2011)

Can somebody tell me how a damned nuclear power plant can be cut off from electricity? It MAKES electricity. Why didn't they use the diesels to run the water pumps and fire the reactors back up to produce more energy?


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## navyasw02 (Mar 12, 2011)

wilheldp_PE said:


> Can somebody tell me how a damned nuclear power plant can be cut off from electricity? It MAKES electricity. Why didn't they use the diesels to run the water pumps and fire the reactors back up to produce more energy?



When shutdown, it can't make electricity. The emergency cooling systems I know of require an external power source. Supposedly (based upon the varying rumors on TV), the backup power systems to run the pumps in case of emergency got taken out by the tsunami. Normally, this wouldn't be as big of a deal because you have a whole power grid to tap into, but in this case you're SOL since half the power grid is down. I suspect their next means of cooling the plant would be to draw off heat by bleeding as much steam as possible if there's a means of putting water back into the steam generators, which is doubtful considering there's no power. The next step would be to tap into the primary (reactor side) piping and pump in and circulate cooling water from an external source. That's pretty much a last resort. You can't fire the thing back up. Not only does it take a long time, but it probably also requires significant inspections to ensure everything is ok after a magnitude ridiculous earthquake.


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## wilheldp_PE (Mar 12, 2011)

navyasw02 said:


> it probably also requires significant inspections to ensure everything is ok after a magnitude ridiculous earthquake.


This is what I wasn't getting. I can understand shutting the reactors down if you have alarms going off all over the place, but nobody really ever said that. It sounded like they just shut the reactors down for shits and grins...going to emergency power for a short time. Wouldn't they have monitors/alarms on everything important (i.e., the stuff that would irradiate the population) if it had been damaged in the earthquake? It seems like they would have better generators/more fuel at something as important as a nuclear power plant.


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## Flyer_PE (Mar 12, 2011)

If I read correctly, the units in question first went in service around 1970. The design standards have changed a LOT since then. I don't know about the Japanese fleet, but there were a whole lot of retrofits here in the states following the TMI event and a lesser known fire at Browns Ferry. The newer plants usually have one more emergency diesel generator (EDG) per unit than the older ones and a lot of the older ones in the states added EDGs in the mid 1980s. Sounds like they had diesel power for about an hour and then it failed for reasons unknown.

Nuclear plants are designed to withstand what is known as a Design Basis Event which is theoretically, the most severe earthquake/weather event that can be postulated. I'm wondering what their design basis is vs. what actually hit them.

As far as getting water in the vessel. These units are Boiling Water Reactors (BWR) and don't have the same primary/secondary systems you find on navy vessels. It's a simple primary loop that actually produces steam in the reactor vessel which is then sent to the main turbine. Without the EDGs, there are two emergency steam driven systems for getting water back in the vessel. The first is RCIC (Reactor Core Isolation Cooling and the second is High Pressure Core Injection (HPCI). If all they had is DC power, their batteries should be sized to control those two systems for a maximum of 8 hours. The theory is that you should be designed such that there are no credible events that will leave you without either off-site power or EDG power for more than either 4 or 8 hours depending on the site. Again, I'm wondering if they messed up the design or just got hit with something beyond what was considered credible when the place was built.


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## navyasw02 (Mar 12, 2011)

Flyer_PE said:


> If I read correctly, the units in question first went in service around 1970. The design standards have changed a LOT since then. I don't know about the Japanese fleet, but there were a whole lot of retrofits here in the states following the TMI event and a lesser known fire at Browns Ferry. The newer plants usually have one more emergency diesel generator (EDG) per unit than the older ones and a lot of the older ones in the states added EDGs in the mid 1980s. Sounds like they had diesel power for about an hour and then it failed for reasons unknown.
> Nuclear plants are designed to withstand what is known as a Design Basis Event which is theoretically, the most severe earthquake/weather event that can be postulated. I'm wondering what their design basis is vs. what actually hit them.
> 
> As far as getting water in the vessel. These units are Boiling Water Reactors (BWR) and don't have the same primary/secondary systems you find on navy vessels. It's a simple primary loop that actually produces steam in the reactor vessel which is then sent to the main turbine. Without the EDGs, there are two emergency steam driven systems for getting water back in the vessel. The first is RCIC (Reactor Core Isolation Cooling and the second is High Pressure Core Injection (HPCI). If all they had is DC power, their batteries should be sized to control those two systems for a maximum of 8 hours. The theory is that you should be designed such that there are no credible events that will leave you without either off-site power or EDG power for more than either 4 or 8 hours depending on the site. Again, I'm wondering if they messed up the design or just got hit with something beyond what was considered credible when the place was built.


I'd guess that for safety's sake, the plant would SCRAM in an extreme earthquake like this. Maybe the aftershocks/tsunamis/natural disasters delayed starting up again beyond the life of the batteries if the emergency diesels went out.


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## wilheldp_PE (Mar 12, 2011)

I understand next to nothing about nuclear energy, but one thing I do know is that when the water stops flowing through the reaction chamber, the fuel rods heat up. When they heat up too much, they fuse together, the reaction runs out of control, and the core melts down (a la Chernobyl). I just don't understand why they shut down the reactors completely (stopping electricity production necessary to run the critical pumps, and allowing the heating process to begin) UNLESS there was some immediately detectable damage to the plant. In the case the there was damage, I completely understand the reason for shutting down...but I haven't found any reports that indicated that there was damage to the reactors.

Alright...I'm done talking out of my ass now. I'm just really tired of people that know even far less than me (i.e., the mainstream media) pitching a shit fit about all this when nothing worse than TMI has occurred yet. They are going to put a stop to all our domestic nuclear energy if they don't knock that shit off.


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## Flyer_PE (Mar 12, 2011)

To get a nuke going, you need the grid. They aren't black-start capable. The reactor recirc pumps are several thousand horsepower alone and the turbines are so big they are damn near uncontrollable if the only load they see is the auxiliary power loads for the station. That, and any event like this, you want all rods in. The problem they have now is dealing with gobs of decay heat and they need power for the low pressure injection systems.

I've been at a station when we has a loss of offsite power and that was a giant PITA with the EDGs working as designed. I can only imagine what those operators are trying to deal with right now.


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## cableguy (Mar 13, 2011)

I'm thinking that building a nuclear plant ON THE OCEAN in an EARTHQUAKE ZONE probably wasn't the best idea.

Call me "Captain Hindsight".


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## benbo (Mar 13, 2011)

Where's Homer Simpson when you need him? Or as he's known in Japan - "Mr. Sparkle."


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## MadDawg (Mar 13, 2011)

cableguy said:


> I'm thinking that building a nuclear plant ON THE OCEAN in an EARTHQUAKE ZONE probably wasn't the best idea.



Tell that to these guys:

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

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

This is all media hype...


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## Flyer_PE (Mar 13, 2011)

Just got this from a friend of mine. Looks like I was wrong about the explosion. The source of the hydrogen was zirconium oxidation.


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## navyasw02 (Mar 13, 2011)

Flyer_PE said:


> Just got this from a friend of mine. Looks like I was wrong about the explosion. The source of the hydrogen was zirconium oxidation.


Thanks for posting this. It looks like we were pretty close in our guesses about what happened. My only question is what caused the loss of coolant? Primary relief valve sticking? System integrity compromised during the quake?


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## navyasw02 (Mar 13, 2011)

cableguy said:


> I'm thinking that building a nuclear plant ON THE OCEAN in an EARTHQUAKE ZONE probably wasn't the best idea.
> Call me "Captain Hindsight".
> 
> The whole country is an earthquake zone. Putting a nuke plant near a water supply is a great place to put it because you can pump seawater in easily in the event of an emergency. It's only a problem in a really complex event like an earthquake followed by a tsunami that shits your whole power grid.


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## navyasw02 (Mar 13, 2011)

Here's another report with some pretty pictures


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## Flyer_PE (Mar 13, 2011)

navyasw02 said:


> Flyer_PE said:
> 
> 
> > Just got this from a friend of mine. Looks like I was wrong about the explosion. The source of the hydrogen was zirconium oxidation.
> ...


Their losing water from it being converted to steam. They have to vent the steam occasionally to control the pressure in the RPV.


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## navyasw02 (Mar 13, 2011)

Flyer_PE said:


> navyasw02 said:
> 
> 
> > Flyer_PE said:
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Gotcha. I'm still thinking of PWRs.


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## Ble_PE (Mar 14, 2011)

wilheldp_PE said:


> Alright...I'm done talking out of my ass now. I'm just really tired of people that know even far less than me (i.e., the mainstream media) pitching a shit fit about all this when nothing worse than TMI has occurred yet. They are going to put a stop to all our domestic nuclear energy if they don't knock that shit off.


This is what I'm worried about. We're still taking baby steps with new-build nuclear and I'm afraid that this is going to set us back because of all the media coverage.

I just hope we've seen the worst of the nuclear problems over there and they get everything under control.


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## wilheldp_PE (Mar 14, 2011)

Ble_PE said:


> This is what I'm worried about. We're still taking baby steps with new-build nuclear and I'm afraid that this is going to set us back because of all the media coverage.
> I just hope we've seen the worst of the nuclear problems over there and they get everything under control.


There was a 2nd hydrogen explosion at the same plant where the first one happened, and they have reported that a third reactor is producing hydrogen at an accelerated rate. The US Navy moved an aircraft carrier that was 100 miles off the coast because of high radiation levels. That can't be a good sign.


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## Capt Worley PE (Mar 14, 2011)

What percentage of Japan's reactors are now offline? I would suspect a good many were scrammed during the earthquake.


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## Flyer_PE (Mar 14, 2011)

I haven't heard anything about the rest of their fleet. If the earthquake where any individual unit is wasn't large enough to trip it off-line, they're probably still running.


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## wilheldp_PE (Mar 14, 2011)

I saw a map of their nuclear power plants (can't remember where). Only two of the plants are experiencing problems. I think the rest of them are still online, including the two nearest the epicenter (the two that are down are farther south of the epicenter).


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## Guest (Mar 15, 2011)

Flyer_PE said:


> Just got this from a friend of mine. Looks like I was wrong about the explosion. The source of the hydrogen was zirconium oxidation.


I just read an IAEA report saying the same that the problem was with the zirconium oxidation.

Also, the largest unit on site (Unit 6) was in a forced outage - good thing or else there would likely be more issues.

Finally, I also read that the grid there is 500 kv and that they were completely knocked offline AND fuel supplies were cutoff from the diesel generators. The only release so far has been tritium (hydrogen gas) and that has been pretty low level. Indications are that reactor core and primary containment are both intact, so primary concern is reducing heat and overpressure. Estimates place it at two weeks for things to cool off.

JR


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## willsee (Mar 15, 2011)

I need updates from educated people on the matter...not media hype.


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## ALBin517 (Mar 16, 2011)

willsee said:


> I need updates from educated people on the matter...not media hype.



Or in the absence of educated people, the men and women of EngineerBoards.com


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## willsee (Mar 16, 2011)

ALBin517 said:


> willsee said:
> 
> 
> > I need updates from educated people on the matter...not media hype.
> ...


Beggars can't be choosers


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## Dleg (Mar 17, 2011)

Absolutely. This is an excellent thread, but why hasn't it been updated? We need updates from all you nukes. I know just enough to be dangerous when it comes to exposure measurement and calcualtions, but nothing at all when it comes to figuring out what the hell is actually happening, and what the risks are.

Can you change the title of the thread so it makes more sense and attracts more attention? (and so I don't forget where it is?)


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## Dleg (Mar 17, 2011)

Jesus.

From CNN:



> The water in the fuel pool served to both cool the uranium fuel and shield it. But once the uranium fuel was no longer covered by water, the zirconium cladding that encases the fuel rods heated, generating hydrogen, said Robert Alvarez, senior scholar at the Institute for Policy Studies and a former official with the Department of Energy.
> That caught fire, resulting in a situation that is "very, very serious," he told CNN.
> 
> He said the next step may involve the remaining 180 nuclear plant workers taking heroic acts.
> ...


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## Capt Worley PE (Mar 17, 2011)

Dleg said:


> Can you change the title of the thread so it makes more sense and attracts more attention? (and so I don't forget where it is?)


Done.

Also, keep in mind that this isn't nearly as bad as Chernobyl, and only 86 people died there. Cancer rates were only 2% higher than normal as well.

Compare that to the number of people killed or injured in traffic accidents each year.


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## willsee (Mar 17, 2011)

Capt Worley PE said:


> Dleg said:
> 
> 
> > Can you change the title of the thread so it makes more sense and attracts more attention? (and so I don't forget where it is?)
> ...


Or how many die in coal mining


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## Capt Worley PE (Mar 17, 2011)

willsee said:


> Capt Worley PE said:
> 
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> > Dleg said:
> ...


That's an even better point.


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## roadwreck (Mar 17, 2011)

Capt Worley PE said:


> willsee said:
> 
> 
> > Capt Worley PE said:
> ...


or how about the earthquake and tsunami which last I heard had claimed over 4000 lives?


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## Flyer_PE (Mar 17, 2011)

If we're comparing relative risk here, I read a news story recently stating that the quake took out a dam/hydro plant. When the dam let loose, 1800 homes were swept downstream. Not much in the news about the dangers of hydro-electric power.


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## willsee (Mar 17, 2011)

Flyer_PE said:


> If we're comparing relative risk here, I read a news story recently stating that the quake took out a dam/hydro plant. When the dam let loose, 1800 homes were swept downstream. Not much in the news about the dangers of hydro-electric power.


Doesn't have the same ring to it/movies behind it as "nuclear"


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## Master slacker (Mar 17, 2011)

I have a Powerpoint presentation of the systems and whatnot, but can't upload it because it's a powerpoint file, I guess. I also have some feedback on the file from a VERY big wig in the international atomic community (brother of a co-worker). Nothing too big, but interesting nonetheless. Any help here?


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## willsee (Mar 17, 2011)

Master slacker said:


> I have a Powerpoint presentation of the systems and whatnot, but can't upload it because it's a powerpoint file, I guess. I also have some feedback on the file from a VERY big wig in the international atomic community (brother of a co-worker). Nothing too big, but interesting nonetheless. Any help here?


Can you convert the slides to PDF and post?


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## Dleg (Mar 17, 2011)

I'd like to see that.

As for the relative death tolls etc. - I agree, but you can't deny the particular horror of a big nuke accident and the possibility of poisoning hundreds or thousands of square miles of land (not to mention the current recommendation to evacuate within 50 miles). That's just simply a different kind of accident than any of the others mentioned.


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## wilheldp_PE (Mar 17, 2011)

The great irony of the total nuclear meltdown that the media would love is that it isn't as big of a disaster as they want it to be. Three Mile Island is inevitably brought up as evidence of the dangers of nuclear power, but if my sources are correct, NOBODY died as a result of that partial meltdown. Chernobyl is undoubtedly the worst nuclear meltdown ever, and it claimed 86 lives. Fer God's sake, they were still running the other reactors at Chernobyl until 2000 (14 years after the meltdown). Not to mention the fact that TMI, Chernobyl, and the Fukushima plant that is currently damaged were all built in the 1970's. Safety systems and procedures are now much better than they were back then due to TMI and Chernobyl.


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## snickerd3 (Mar 17, 2011)

they have begun opening parts of chernobyl back up...albeit limited to guided tours, but they are letting people in again.


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## Master slacker (Mar 17, 2011)

willsee said:


> Can you convert the slides to PDF and post?


Good suggestion. It's attached.

Here is the feedback. FYI, River Bend is a nuke plant about 20'ish miles north of me.



> Mostly accurate. The German plant is a newer design/model (BWR 5 or 6) than the Japanese model (BWR3 with a Mark 1 containment). HPCI/HPCS is not a backup to RCIC. RCIC is about 1/10 the size of HPCS/HPCI, and is for a different purpose (Isolation cooling instead of emergency injection). HPCS is motor driven; HPCI is turbine driven. River Bend is a BWR 6 with a Mark 3 containment. At least one of the Japan units has an isolation condenser system instead of a RCIC. Can't vouch for the accuracy.


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## Guest (Mar 17, 2011)

Good stuff Master Slacker.

Reuters offered up a chronology/risk assessment pdf also ...

Japan's Race Against Time

JR


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## Capt Worley PE (Mar 17, 2011)

Thanks, MS. pretty good coverage.


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## Flyer_PE (Mar 17, 2011)

Found the following here.



> UPDATE AS OF 9:15 P.M. EDT, THURSDAY, MARCH 17:
> Tokyo Electric Power Co. said it hopes to activate the cooling system for Fukushima Daiichi reactor 2 "as early as Friday night" (Japan time). The company said it could restore power from the electric grid to reactor 2 by Thursday night (U.S. time).
> 
> The International Atomic Energy Agency reported that TEPCO completed connecting electrical cable from a makeshift transformer to reactor 2 at 4:30 A.M. EDT. Engineers were waiting to complete spraying sea water into the reactor 3 fuel pool before they restore power through the cable to the reactor 2 cooling system.
> ...


To give a frame of reference, we were always told in the annual training that a chest x-ray was about a 50mr dose. The x-rays the dentist used to take of your teeth was about 10mr of exposure. A 30mr field all the way out at the gate is sobering but it's not a level that warrants mass hysteria.

Disclosure: 600mr lifetime accumulated dose from 8 years working at a BWR.


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## navyasw02 (Mar 17, 2011)

Flyer_PE said:


> Found the following here.
> 
> 
> 
> ...


Still, I wouldn't want to hang out there. I think that's more in an hour than I got in a month on my dosimetry reports. What are the legal exposure limits? I cant remember those numbers off the top of my head anymore.


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## Dleg (Mar 17, 2011)

Great info, guys. Keep it coming!


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## Guest (Mar 17, 2011)

Flyer_PE said:


> Found the following here.
> 
> 
> 
> ...


Good info.



navyasw02 said:


> Still, I wouldn't want to hang out there. I think that's more in an hour than I got in a month on my dosimetry reports. What are the legal exposure limits? I cant remember those numbers off the top of my head anymore.


When I was doing inspections, my limit was 5 mrem/hr total body count.

JR


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## chaosiscash (Mar 18, 2011)

We're limited at the ACL to 1 rem (not mrem) a year. The DOE ACL is 2 rem and the DOE limit is 5 rem. Those are all whole body. The extremity limit is something like 50 rem and the pregnant female limit is much lower, although most pregnant women around here self-declare and are moved to a no dose area. Of course, those numbers are for Radworker II's. The limits for the general public are much, much lower. For a little perspective, the average annual dose for the general population from natural background and manmade sources is around 350 mrem. This includes medical x-rays, radon, etc.

Source: Just took my biannual Radworker II training a few days ago.


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## Flyer_PE (Mar 18, 2011)

Typical limits for the nuclear utilities here are half the DOE/NRC limits. The max I've passed through was a 1R/hr field. I sure as hell wasn't loitering.


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## Dleg (Mar 18, 2011)

I used to use Cesium 137 gamma ray sources and Americium 241-Beryllium neutron sources in the oil field, and as district radiation engineer, I got the honor (ahem) of being in charge of the wipe testing of all the sources we used. These were big well logging sources - way bigger than the typical civil engineering compaction tester sources. If I remember correctly, the cesium source was 1.7 curies, and the Am241Be was a whopping 16 Curies.

I did that for 4.5 years and walked away with a "lifetime" exposure of over 2,000 mrem. 1250 of that was "administrative" and not measured - some jackass left a cesium source out of its shield for three days in the shop, attached to the end of the handling tool in the back of his truck while we all worked. The CA NRC (or whatever CA called it) took all our badges and just assigned us a calculated, worst-case dose from the incident.

I've talked to nuclear submarine offices who are shocked at my exposure levels, even though they're way under the very conservative occupational limits. I guess a properly run nuclear power plant doesn't put out much radiation.


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## Flyer_PE (Mar 18, 2011)

^It depends on what you're working on. Some of the instrument techs were up in the 5R range. Some of the vessel instrumentation was pretty hot. The stuff I mostly worked with was either in a 0-rad area (Batteries, switchgear, etc) or was only a radiation area when we were on-line (Main Turbine, Feedwater Heat/Reheat, etc). We didn't do much adjusting on the turbine and accessories when we were running.


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## navyasw02 (Mar 18, 2011)

Dleg said:


> I've talked to nuclear submarine offices who are shocked at my exposure levels, even though they're way under the very conservative occupational limits. I guess a properly run nuclear power plant doesn't put out much radiation.


When I was on a sub, I think my monthly doses were in the single digit mr range. I think I got less being underway than I did just by walking around and getting sunshine.


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## cableguy (Mar 21, 2011)

So do you think the Japanese should make a deal something like this...

Take a prisoner, who's incarcerated for life with no chance for parole. Offer to pay them $100,000 if they'll work at the plant under 'dire' conditions (as in, they'll probably die from exposure), and offer to expunge their record (post-mortem) and give them a hero's funeral.

Think anyone would go for that? I think it'd be worth it to try. They essentially need some Kamikaze plant workers at this point... willing to "die for the greater good". Some of them may be at that point anyway.


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## Guest (Mar 21, 2011)

A pretty good basis of information for the current status ...

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

JR


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## willsee (Jun 20, 2011)

Update

http://bigthink.com/ideas/38924


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