Japan's Nukes Following Earthquake

[matthew.b]

It isn't about the turbine, it was about the containment. Eventually, containment parameters degrade to the point where the emergency procedures direct you to stop all discharges to containment from things like steam driven pumps.

That's a heck of a bind to be in.

You'd think the better choice would be to vent containment and keep the pump running to prevent cladding damage.  Either way the drywell is going to be vented, the better choice would be to not vent with cladding damage.

[hamsamich]

"You'd think the better choice would be to vent containment and keep the pump running to prevent cladding damage.  Either way the drywell is going to be vented, the better choice would be to not vent with cladding damage."

This is getting to the meat of one of my questions, a discussion on this point.  Thanks everyone for further input.

[S_Phoenix]

Posted on facebook.

"7th Fleet repositions ships after contamination detected
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 radio...activity 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.  See More
By: U.S. 7th Fleet"


This does not sound good.  If they are finding it that far out to sea, seems to lead to the fuel cell damage is worse than reported.

[JustinHEMI05]

That's a heck of a bind to be in.

You'd think the better choice would be to vent containment and keep the pump running to prevent cladding damage.  Either way the drywell is going to be vented, the better choice would be to not vent with cladding damage.

Well my answer was based on "normal" EOP space. Once you get past a certain point, you are into the "severe accident mitigation procedures." I am sure they are well into those and my knowledge of them is limited. However, in EOP space, from what I remember, protecting your ability to perform a reactor blowdown is a high priority. However, keeping the core covered is also, a high priority, so they are sort of competing. One of those legs should have driven them to blowing down the reactor before losing the ability to supress it or before reactor level dropped below the top of active fuel. I don't know how strong their RCIC is, but I can tell you, that for the first 15 minutes or so after a trip from full power on RCIC alone at Peach Bottom, RCIC will NOT maintain level. So what I am saying is... I really have no idea how they got themselve in. What I know from Peach Bottom cannot be directly correlated to their plant because A) they are somewhate different and B) They had an 8.9 earth quake. This is why I have refrained from further speculation of what is going on because it is beyond anything calculated or planned for at this point. I just try to think about what I would be trying to do if I was in their situation.

Justin

[Dave Warren]

The latest from Yahoo News:

Water levels dropped precipitously Monday inside a stricken Japanese nuclear reactor, twice leaving the uranium fuel rods completely exposed and raising the threat of a meltdown, hours after a hydrogen explosion tore through the building housing a different reactor.

Water levels were restored after the first decrease but the rods remained exposed late Monday night after the second episode, increasing the risk of the spread of radiation and the potential for an eventual meltdown.

[JustinHEMI05]

Well my answer was based on "normal" EOP space. Once you get past a certain point, you are into the "severe accident mitigation procedures." I am sure they are well into those and my knowledge of them is limited. However, in EOP space, from what I remember, protecting your ability to perform a reactor blowdown is a high priority. However, keeping the core covered is also, a high priority, so they are sort of competing. One of those legs should have driven them to blowing down the reactor before losing the ability to supress it or before reactor level dropped below the top of active fuel. I don't know how strong their RCIC is, but I can tell you, that for the first 15 minutes or so after a trip from full power on RCIC alone at Peach Bottom, RCIC will NOT maintain level. So what I am saying is... I really have no idea how they got themselve in. What I know from Peach Bottom cannot be directly correlated to their plant because A) they are somewhate different and B) They had an 8.9 earth quake. This is why I have refrained from further speculation of what is going on because it is beyond anything calculated or planned for at this point. I just try to think about what I would be trying to do if I was in their situation.

Justin

Oh I forgot to add, that RCIC alone also would not have degraded the containment at PB as fast as happened there. So in my mind, they obviously had some other discharge going on, despite the updates saying they didn't suspect a leak. But like I said, I don't know, because I'm not there or have the experience of having the earth torn beneath my feat while operating.

At PB, after the first 15 minutes, RCIC was the one little reliable guy that could.

[BWB519]

"You'd think the better choice would be to vent containment and keep the pump running to prevent cladding damage.  Either way the drywell is going to be vented, the better choice would be to not vent with cladding damage."

This is getting to the meat of one of my questions, a discussion on this point.  Thanks everyone for further input.

What point are you questioning exactly?

[atomicarcheologist]

"7th Fleet repositions ships after contamination detected
  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. 

This begs the question of when where the crew members contaminated?  If it was during a recon flight, then why weren't they closed in the cabin with A/C (recirc sys) operational and if it was while they were on the ground, what must the conditions be like there?

[spentfuel]

A few comments from what I have heard and read.

The hydrogen is from a combination of Hydrolysis/Radiolysis and has nothing to do with water chemistry cause there flooding the core with sea water !!!  The reports of rad sickness are likely because of some of the reports of up to 1500 people have been scanned for "radiation"

The highest dose I have heard was 10.5 rem to a plant worker and highest dose rate was 128 mr/hr at the site boundary.

If they are getting the core flooded with sea water then they are venting the hydrogen pressure off to either the drywell and or the reactor building proper once it combines with O2 and reached and explosive concentration it just take a static spark to ignite.

not a BWR expert by any means but that what I have read

sf

[dad]

Posted on facebook.

"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.     "


This does not sound good.  If they are finding it that far out to sea, seems to lead to the fuel cell damage is worse than reported.

Aircraft fly from the fleet to Japan and back.  Nothing in this article tells you how far out to Sea an aircraft was when it detected radiation.  Nothing in this article tells where the aircraft picked up the low level radiation contamination found on the aircraft.

Repositioning the ships to avoid flying through air which is downwind of the reactors is prudent, regardless how close to shore the radiation was detected / picked up.

[spentfuel]

Meanwhile, 17 U.S. military personnel involved in helicopter relief missions were found to have been exposed to low levels of radiation after the flew back from the devastated coast to the USS Ronald Reagan, an aircraft carrier about 100 miles (160 kilometers) offshore.

U.S. officials said the exposure level was roughly equal to one month's normal exposure to natural background radiation, and the 17 were declared contamination-free after scrubbing with soap and water.

As a precaution, the U.S. said the carrier and other 7th Fleet ships involved in relief efforts had shifted to another area.

from a new article I read.

sf

[BWB519]

Well my answer was based on "normal" EOP space. Once you get past a certain point, you are into the "severe accident mitigation procedures." I am sure they are well into those and my knowledge of them is limited. However, in EOP space, from what I remember, protecting your ability to perform a reactor blowdown is a high priority. However, keeping the core covered is also, a high priority, so they are sort of competing. One of those legs should have driven them to blowing down the reactor before losing the ability to supress it or before reactor level dropped below the top of active fuel. I don't know how strong their RCIC is, but I can tell you, that for the first 15 minutes or so after a trip from full power on RCIC alone at Peach Bottom, RCIC will NOT maintain level. So what I am saying is... I really have no idea how they got themselve in. What I know from Peach Bottom cannot be directly correlated to their plant because A) they are somewhate different and B) They had an 8.9 earth quake. This is why I have refrained from further speculation of what is going on because it is beyond anything calculated or planned for at this point. I just try to think about what I would be trying to do if I was in their situation.

Justin

I agree with you here.  You would have the Heat Capacity Limit of your Torus that would drive you to lower RPV pressure or cool the Torus per an EOP.  But, lets not forget that they were also in a station blackout.  Other than minimizing DC loads to preserve much needed battery power, you would definately disable some interlocks.  I would think HPCI and RCIC area temps and Low Pressure lockout for RCIC.  After you lockout the low pressure isolation, running RCIC without throttling the pump discharge (which will minimize the time needed to run the pump and thereby keep the heating of the Torus to a minimum) will maintain RPV level and also lower RPV pressure (which will help with the EOP heat capacity curve).  HPCI is also a viable method of lowering pressure and injecting to the RPV.  The lower you can get RPV pressure the higher you can raise temperature in the Torus.

[hamsamich]

Thanks Justin.


BWB519  -   Wondering what happened to RCIC, which also MIGHT have something to do with the suppression pool, which might have something to do with why the RB blew up.  So I guess Directly the RCIC point, but also since everything ties into the RB blowing up that too, indirectly.

A BWR SRO friend of mine thinks the battery/electric power issue would have caused a problem before the suppression pool would have concerning RCIC.  At a PWR now, so he may be rusty.  Alot of speculation but I'd really like to know what happened.

[Cycoticpenguin]

Aircraft fly from the fleet to Japan and back.  Nothing in this article tells you how far out to Sea an aircraft was when it detected radiation.  Nothing in this article tells where the aircraft picked up the low level radiation contamination found on the aircraft.

Repositioning the ships to avoid flying through air which is downwind of the reactors is prudent, regardless how close to shore the radiation was detected / picked up.

Re read the article... Clearly states 100 miles off the coast, clearly states the radiation came from a plume from the plant, states where they picked up radiation, etc.

I do agree that moving is prudent.

[HydroDave63]

This begs the question of when where the crew members contaminated?  If it was during a recon flight, then why weren't they closed in the cabin with A/C (recirc sys) operational and if it was while they were on the ground, what must the conditions be like there?

The proof in the pudding will be if/when Columbia Gen and Hanford get hot air samples....  

[BWB519]

Thanks Justin.


BWB519  -   Wondering what happened to RCIC, which also MIGHT have something to do with the suppression pool, which might have something to do with why the RB blew up.  So I guess Directly the RCIC point, but also since everything ties into the RB blowing up that too, indirectly.

A BWR SRO friend of mine thinks the battery/electric power issue would have caused a problem before the suppression pool would have concerning RCIC.  At a PWR now, so he may be rusty.  Alot of speculation but I'd really like to know what happened.

I can only speculate what happened.  In a station blackout situation, depressurizing via SRVs, HPCI, and RCIC to achieve whatever cooldown rate they are allowed and fill the RPV would be a prudent choice.  This could have been challenged by any number of things.  Maybe they can't bypass their low pressure isolation logic that would stop them from running RCIC down to around 150# or so.  Or, maybe there was a LOCA that challenged containment before RCIC ever would have.  I think being in the DC power box would challenge the operators as well, but there are ways around/out of that box.

[dad]

Re read the article... Clearly states 100 miles off the coast, clearly states the radiation came from a plume from the plant, states where they picked up radiation, etc.

I do agree that moving is prudent.

The article never states the aircraft picked up the radiation 100 miles off the coast.

Get your facts straight.

[Cycoticpenguin]

The article never states the aircraft picked up the radiation 100 miles off the coast.

Get your facts straight.

we're not about to argue on this thread. If you cant read, sorry.

[S_Phoenix]

The article never states the aircraft picked up the radiation 100 miles off the coast.

Get your facts straight.

From USS Ronald Reagan Commanding Officer:
Friends and Family of USS Ronald Reagan:   I want to take this opportunity to personally assure you that first and foremost all personnel aboard the USS Ronald Reagan are safe and healthy.   During our mission to assist our close allies of Japan, we were ...operating near the radioactive plume from Fukushima Dai-Ichi Nuclear Power Plant.  As you may have already heard, radioactivity was detected on 17 personnel from our ship, however, we promptly took the proper precautions and the radioactivity was easily removed by using soap and water.  The levels that were detected were very low levels. To put this into perspective, the maximum radiation dose received was equalt to the amount of natural background radiation one would receive in one month from sources such as rocks, soil and the sun.   Ronald Reagan has since repositioned away from the Fukushima Dai-Ichi Nuclear Power Plant.   As a nuclear-powered aircraft carrrier, we have extensive technical expertise onboard to properly monitor such types of risks, and if necessary, rapidly resolve the situation.   We have taken all the necessary precautions to ensure that everyone is safe. We have closely monitored spaces, evaluated everyone who has flown or worked on the flight deck and cleaned the aircraft.   I have not seen any levels of radiation or contamination that would cause me to have any significant concerns at all.   As we continue to assist Japan in this terrible catastrophe, our Sailor's--and your loves ones'-- safety will remain at the top of my priority list.   Capt. Thom BurkeSee More
By: USS Ronald Reagan

Lets say I know more info and you can't read.

[JustinHEMI05]

I can only speculate what happened.  In a station blackout situation, depressurizing via SRVs, HPCI, and RCIC to achieve whatever cooldown rate they are allowed and fill the RPV would be a prudent choice.  This could have been challenged by any number of things.  Maybe they can't bypass their low pressure isolation logic that would stop them from running RCIC down to around 150# or so.  Or, maybe there was a LOCA that challenged containment before RCIC ever would have.  I think being in the DC power box would challenge the operators as well, but there are ways around/out of that box.

Yup the sort of stuff I been thinking about. From the earliest status reports I saw, HPCI was never available. I have been assuming that either a) it was broke) or b) they didn't use it because with no way to cool the torus, they would have challenged containment quickly by using HPCI.

But it is all speculation. I can only imagine going down my legs going "nope that is broke, next." "nope that is broke, next."

[dad]

Again, no where does the article say the the aircraft picked up the radiation 100 miles off the coast.

You keep posting an article that proves my points - what exactly is the point you are trying to make.

Again, the aircraft being tested just flew round trip from the ships, to Japan, and back to the ships...

[Marlin]

Please post sources that would help information flow.

http://edition.cnn.com/2011/WORLD/asiapcf/03/14/japan.us.navy.radiation/index.html?eref=edition_asia&cid=dlvr.it

Tests detected low levels of radioactivity on 17 U.S. Navy helicopter crew members when they returned to the USS Ronald Reagan after conducting disaster relief missions in Japan, the military said Monday.
No further contamination was detected after the crew members washed with soap and water, the Navy said.
In addition, the Navy said the U.S. 7th Fleet has temporarily repositioned its ships and planes away from the Fukushima Daiichi nuclear power plant after detecting low-level contamination in the air and on its planes in the area, the Navy said.
One ship was operating about 100 miles northeast of the power plant when "airborne radioactivity" was detected, the Navy said.
The Navy's statement, however, provided some perspective, noting that the maximum potential radiation dose received by personnel when the ship 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."

http://www.cbsnews.com/stories/2011/03/14/501364/main20042763.shtml

CBS News national security correspondent David Martin reports that there were two separate radiation exposures on the aircraft carrier USS Ronald Reagan. The first was to air crews who were swabbed upon returning from search and rescue (SAR) missions, 17 of whom were found to have received the equivalent of a month's radiation and had to be decontaminated.
The second exposure occurred when the carrier's shipboard alarms went off. Since the Reagan is nuclear-powered, it has sensors to detect radioactivity, said Martin, and those went off as soon as the radiation levels went above the naturally-occurring background.
The Reagan was about 100 miles offshore when its instruments detected the radiation.
The fleet said that the radiation was from a plume of smoke and steam released from the crippled Fukushima Dai-Ichi Nuclear Power Plant, where there have been two hydrogen explosions since Friday's devastating earthquake and tsunami.
But there were "really, really low levels," and not considered a hazard to health, reports Martin.

[dad]

Please post sources that would help information flow.

http://edition.cnn.com/2011/WORLD/asiapcf/03/14/japan.us.navy.radiation/index.html?eref=edition_asia&cid=dlvr.it

Tests detected low levels of radioactivity on 17 U.S. Navy helicopter crew members when they returned to the USS Ronald Reagan after conducting disaster relief missions in Japan, the military said Monday.
No further contamination was detected after the crew members washed with soap and water, the Navy said.
In addition, the Navy said the U.S. 7th Fleet has temporarily repositioned its ships and planes away from the Fukushima Daiichi nuclear power plant after detecting low-level contamination in the air and on its planes in the area, the Navy said.
One ship was operating about 100 miles northeast of the power plant when "airborne radioactivity" was detected, the Navy said.
The Navy's statement, however, provided some perspective, noting that the maximum potential radiation dose received by personnel when the ship 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."

http://www.cbsnews.com/stories/2011/03/14/501364/main20042763.shtml

CBS News national security correspondent David Martin reports that there were two separate radiation exposures on the aircraft carrier USS Ronald Reagan. The first was to air crews who were swabbed upon returning from search and rescue (SAR) missions, 17 of whom were found to have received the equivalent of a month's radiation and had to be decontaminated.
The second exposure occurred when the carrier's shipboard alarms went off. Since the Reagan is nuclear-powered, it has sensors to detect radioactivity, said Martin, and those went off as soon as the radiation levels went above the naturally-occurring background.
The Reagan was about 100 miles offshore when its instruments detected the radiation.
The fleet said that the radiation was from a plume of smoke and steam released from the crippled Fukushima Dai-Ichi Nuclear Power Plant, where there have been two hydrogen explosions since Friday's devastating earthquake and tsunami.
But there were "really, really low levels," and not considered a hazard to health, reports Martin.

I stand corrected.

[MacGyver]

Again, no where does the article say the the aircraft picked up the radiation 100 miles off the coast.

You keep posting an article that proves my points - what exactly is the point you are trying to make.

Sir, you are wrong.  Please stop posting on this topic (re: 100 miles).  Thank you.

[matthew.b]

The proof in the pudding will be if/when Columbia Gen and Hanford get hot air samples....  

Or Reed College or Oregon State University