Japan hit by 8.9 Magnitude Quake, Tsunami Warnings In Effect

[leswp1]

Re: Japan hit by 8.9 Magnitude Quake, Tsunami Warnings In Effect

NPR had a really good show on today about the reactors and saying the same thing you all are saying regarding the risk being less than the hype. Had great detail about all the different possible scenarios, explained the way things worked etc. Now I am listening to the local TV news. Everything will explode- YESTERDAY!1!11!11111!!!!

 

[huskyfan]

Re: Japan hit by 8.9 Magnitude Quake, Tsunami Warnings In Effect

nothing will "explode" as in nuclear bomb explode. but it could leak. a bunch. in a worst case scenario.

didn't Chernobyl drop radiation all over the Ukraine and Scandinavia? lots of cancers years later. aren't there still areas that are inhabitable? I would guess the population density is way more in Japan.

 

[Patman]

Re: Japan hit by 8.9 Magnitude Quake, Tsunami Warnings In Effect

I guess to put in prespective, I live a lot closer and I just thought "I should look into to getting some iodine tablets...."

honestly, I would have done the same... i think the largest issue is that its something we treat with mysticism... the human eye can see coal and oil burn... can see the power of water... the power of an atom... and it does magical things... and could kill you without knowing... good luck with that.

 

[dxmnkd316]

Re: Japan hit by 8.9 Magnitude Quake, Tsunami Warnings In Effect

Also, if they have been venting hydrogen gas, then they haven't reached the setpoints of the safety relief valves. And those are well below the Maximum Allowed Working Pressure the Rx vessel was designed for. So I doubt there was a steam explosion.

Not necessarily. Often the relief set point is equal to the MAWP for the vessel. The MAWP for most of the registered pressure vessels I work with is 150 psig. Depending on the type of reactor, the contents of the reactor, and the downstream destination of the relief line, the relief valve will have a set pressure of 50 psig to 150 psig (relieving at 50 to 165 psig depending on the allowable overpressure limits).

It also sounds like these aren't relief valves that are going off so much as they are vent lines with pressure control valves or some other automatic on/off valve. It sounded like the venting was triggered by the operators and not a PSV.

 

[leswp1]

Re: Japan hit by 8.9 Magnitude Quake, Tsunami Warnings In Effect

nothing will "explode" as in nuclear bomb explode. but it could leak. a bunch. in a worst case scenario.

didn't Chernobyl drop radiation all over the Ukraine and Scandinavia? lots of cancers years later. aren't there still areas that are inhabitable? I would guess the population density is way more in Japan.

I know it won't explode but that was the headline on the local station.

They actually did a spot on the Chernobyl area that was fascinating. There are farmers who are living there off the land. The level of cancer is not much higher than the general pop. They were saying this is probably due to the spotty nature of how the radiation settled. They were also waying some reasearch shows that a minimal level above normal radiation can actually make people healthier but the level is miniscule and obviously not controllable in this situation. Would love to see that study.

 

[dxmnkd316]

Re: Japan hit by 8.9 Magnitude Quake, Tsunami Warnings In Effect

nothing will "explode" as in nuclear bomb explode. but it could leak. a bunch. in a worst case scenario.

didn't Chernobyl drop radiation all over the Ukraine and Scandinavia? lots of cancers years later. aren't there still areas that are inhabitable? I would guess the population density is way more in Japan.

Again, Chernobyl was a completely different design. First, the control rods were graphite. When the core had a meltdown, the graphite caught fire. This exacerbated the problem. Eventually, this caused an explosion that was not contained because the reactor did not have the "last resort" containment vessel constructed of multiple feet of reinforced concrete.

 

[dxmnkd316]

Re: Japan hit by 8.9 Magnitude Quake, Tsunami Warnings In Effect

honestly, I would have done the same... i think the largest issue is that its something we treat with mysticism... the human eye can see coal and oil burn... can see the power of water... the power of an atom... and it does magical things... and could kill you without knowing... good luck with that.

quite frankly, it will just be squandered by the people who likely bought them. It would have been much, much better to have them sent to local hospitals instead where medical professionals would be able to give them to the individuals who would need them in an emergency.

Simply put, we're not going to see a Chernobyl-style blast. This has come from numerous sources much, much smarter than anyone on this board. I wouldn't completely rule it out, but the odds are slim to none. The radioactive isotopes vented from the reactor so far have had half lives measured in seconds.

The levels of radioactivity measured so far have barely exceeded the levels you get from a CT scan. Additionally, the measured levels of radioactivity do not necessarily mean the amount of radioactivity the body absorbs.

 

[5mn_Major]

Re: Japan hit by 8.9 Magnitude Quake, Tsunami Warnings In Effect

I know it won't explode but that was the headline on the local station.

They actually did a spot on the Chernobyl area that was fascinating. There are farmers who are living there off the land. The level of cancer is not much higher than the general pop. They were saying this is probably due to the spotty nature of how the radiation settled.

Did a lot of research on Chernobyl a decade ago...and that is my assessment as well. The eastern european alarm seemed to result in no recognizable increase from what I recall.

 

[Wol4ine]

Re: Japan hit by 8.9 Magnitude Quake, Tsunami Warnings In Effect

Again, Chernobyl was a completely different design. First, the control rods were graphite. When the core had a meltdown, the graphite caught fire. This exacerbated the problem. Eventually, this caused an explosion that was not contained because the reactor did not have the "last resort" containment vessel constructed of multiple feet of reinforced concrete.

I don't think they used graphite for the control rods, it was used as the moderator.

edit:

But the control rods had a design flaw that now proved deadly: their tips were made of graphite. The graphite tips attached to a hollow segment one meter (3.28 feet long), which attached in turn to a five-meter absorbent segment. When the 205 control rods began driving into the surging Number 4 reactor, the graphite tip went in first. Rather than reduce the reaction, the graphite tips increased it. The control rods displaced water from the rod channels as well, increasing reactivity further. All hell broke loose--The reactor exploded.

I stand corrected. I trained at MARF up in Balston Spa, NY. We had water filled control tubes instead of normal control rods. I 'used' to think that was screwy.

 

[dxmnkd316]

Re: Japan hit by 8.9 Magnitude Quake, Tsunami Warnings In Effect

I don't think they used graphite for the control rods, it was used as the moderator.

You're right. My mistake. Graphite moderator in Chernobyl. Water moderator in Japan.

 

[huskyfan]

Re: Japan hit by 8.9 Magnitude Quake, Tsunami Warnings In Effect

ok. I'm a total newbie to this stuff (in fact I think I learned more today about nuclear power than I had in my whole life) - but the bloggers seem more worried about the spent fuel catching fire - they are put into water? and that water is dropping? has dropped? is gone? and they spent fuel can catch fire? spontaneously? is that right? I'm also reading about panic starting among the people in the near area. and some are talking about the Fukushima 50 - those who stayed behind to continue running the plant. poor poor Japan. the triple disaster and now who knows? famine, disease, economic crisis?

 

[huskyfan]

Re: Japan hit by 8.9 Magnitude Quake, Tsunami Warnings In Effect

a question. they also talk about radiation levels being 4x higher, 30x higher, etc. I understand that flying, hanging around the trinity site, radon in the home, xrays,
etc etc raise ones exposure level. but how high is too high? when does it go from normal non threatening exposure to radiation poisoning?

 

[huskyfan]

Re: Japan hit by 8.9 Magnitude Quake, Tsunami Warnings In Effect

and what is cold shutdown status?

my non scientific brain is about to explode. I pray I awake in the morning to find all is well.

 

[Wol4ine]

Re: Japan hit by 8.9 Magnitude Quake, Tsunami Warnings In Effect

and what is cold shutdown status?

my non scientific brain is about to explode. I pray I awake in the morning to find all is well.

On the sub our goal was to pull into port, then "shut down, cool down, depressurize". Once you insert the control rods to stop the fission, there is decay of uranium byproducts in the fuel rods. These still generate heat for a while. IIRC a cold shut down means these have sufficiently decayed and the temperature in the core is going down. A hot shutdown is driving control rods in only so far so as to maintain a temperature so that you can start up again quickly.

 

[dxmnkd316]

Re: Japan hit by 8.9 Magnitude Quake, Tsunami Warnings In Effect

Let me put this bluntly. There isn't a goddam person on this earth who understands what's going on. Now we don't know if measurements were in micro- or millisieverts. Brilliant. Just f*king brilliant.

 

[dxmnkd316]

Re: Japan hit by 8.9 Magnitude Quake, Tsunami Warnings In Effect

a question. they also talk about radiation levels being 4x higher, 30x higher, etc. I understand that flying, hanging around the trinity site, radon in the home, xrays,
etc etc raise ones exposure level. but how high is too high? when does it go from normal non threatening exposure to radiation poisoning?

http://en.wikipedia.org/wiki/Radiation_poisoning#Exposure_levels

A microsievert is 1/1,000,000 of a sievert.

 

[leswp1]

Re: Japan hit by 8.9 Magnitude Quake, Tsunami Warnings In Effect

a question. they also talk about radiation levels being 4x higher, 30x higher, etc. I understand that flying, hanging around the trinity site, radon in the home, xrays,
etc etc raise ones exposure level. but how high is too high? when does it go from normal non threatening exposure to radiation poisoning?

The level when you go from a healthy exposure to one that is harmful is variable dependent upon the person from what I can understand. Obviously when they get into the very high range that is a no brainer.

 

[Kepler]

Re: Japan hit by 8.9 Magnitude Quake, Tsunami Warnings In Effect

NPR had a really good show on today about the reactors and saying the same thing you all are saying regarding the risk being less than the hype. Had great detail about all the different possible scenarios, explained the way things worked etc. Now I am listening to the local TV news. Everything will explode- YESTERDAY!1!11!11111!!!!

There's always going to be the problem of the media pushing doom and the industry saying "nothing to see here, move along." Each has zero real informational content.

One very brief primer as an attempt to get a baseline of trustable info.

 

[alfablue]

Re: Japan hit by 8.9 Magnitude Quake, Tsunami Warnings In Effect

More importantly, in between the reactor coverage, on Morning Edition, NPR interviewed an older guy who was preapring to start a wood fire, so that he can boil what water he had, and cook what food he had, for over 100 people who were in the same place as he was.

We seem to miss the point that this tragedy is so big that even a government has a tough time dealing with it. No army or resources are large enough to fix problems. Even the people who CAN move to the south- it will be tough for society to absorb that many people. We can't forget that 7% of the entire country's power is out. Entire country.

I personally have no idea how many people lost their homes. It's got to be a very, very high number. And even if your home survived close to the quake- there's not much around that's capable of sustaining you, thanks to the damage.

Haiti was bad in the damage and loss of lives. This quake was alomst 100x stronger, and was accompanied by a tsunami. This is bad, too.

again, with all due respect to the reactor, and it's issues, in the scheme of things, it's quite minor.

(and on a very dark, dark, dark note, Japan has dealt with some rather harsh nuclear fallout.... worse than Chernobyl. By a wide margin. Twice.)

 

[Kepler]

Re: Japan hit by 8.9 Magnitude Quake, Tsunami Warnings In Effect

I personally have no idea how many people lost their homes. It's got to be a very, very high number. And even if your home survived close to the quake- there's not much around that's capable of sustaining you, thanks to the damage.

Australia's world band station was reporting 500,000 people have been "displaced." I don't know whether that means permanent loss of home or those people plus all those temporarily homeless because of evacuation, damage, and now the nuclear situation.

To put it in perspective, that's almost the entire population of Vermont. About 250,000 people were temporarily homeless after Katrina.

OTOH, in Haiti there were 1.5 million homeless and 300,000 dead out of a total population of 9.7 million.