Register | Sign In


Understanding through Discussion


EvC Forum active members: 58 (9173 total)
3 online now:
Newest Member: Neptune7
Post Volume: Total: 917,567 Year: 4,824/9,624 Month: 172/427 Week: 85/85 Day: 2/20 Hour: 0/1


Thread  Details

Email This Thread
Newer Topic | Older Topic
  
Author Topic:   Japan
dronestar
Member
Posts: 1425
From: usa
Joined: 11-19-2008
Member Rating: 5.5


Message 136 of 175 (609564)
03-21-2011 1:16 PM
Reply to: Message 132 by Percy
03-20-2011 8:15 AM


Re: Information
Thanks for weighing in Percy, although maybe your post (and mine) would have been better in the other "is nuclear safe" thread.
I've done a lot of reading about Fukushima, nuclear power, and other power sources lately. It seems one needs an advanced education about any/each/all of them to talk with a degree of accuracy so I hesitate to offer additional information:
As you have alluded in your post, according to the following article, the term "spent" fuel rods are not really spent:
Spent is an industry-euphemism. It implies something harmless, wasted or used up. Quite the opposite.
Spent fuel is irradiated fuel: fuel that has been irradiated inside a nuclear reactor’s core. After removal from the reactor, this fuel is massively contaminated with radioactive elements and must be stored in giant pools.
On March 15 the New York Times said these fuel pools could pose an even greater danger than the reactors melting down.
An even greater danger? Isn’t a core meltdown as bad as it gets?
Alas, a fuel pool meltdown could be worse than a reactor core meltdown. Much worse. This is because fuel pools contain far more radioactivity than that which is inside a reactor core. Unfortunately, at Fukushima we may get both types of meltdowns.
Robert Alvarez, formerly of the US Department of Energy and now at the Institute of Policy Studies, provided insight into this potential nuclear Armageddon. In a recent blog Alvarez states the fuel in each of the pools at the Fukushima complex has 5 to 10 times the radioactivity of the fuel inside one reactor core. And much of this radioactive material is the highly toxic and long-lived radionuclide, cesium-137. See.)
Another problem: Unlike the reactor cores, which have a hefty, six-inch thick steel containment vessel, the fuel pools at Fukushima are in unhardened and therefore highly vulnerable concrete structures. The roof of one of these structures has been completely demolished in at least one of the stricken reactors, Unit 4.
Why is irradiated fuel sitting in pools? (They’re sort of like swimming pools, though considerably deeper. About 40 feet long, 40 feet wide and 45 feet deep.)
After removal from the reactor core, the irradiated fuel is fiendishly hot. The fuel is so hot it will cause the water it is immersed in to boil — if the water is not cooled. What if fuel pool’s cooling systems fail? Disaster. If the water is not cooled for a certain number of days or weeks, the water will boil off. Next, the fuel can catch fire, releasing its toxic load to the environment.
Japan’s Nuclear Armageddon and the Experts « Aletho News
I am unsure if there are similarly designed and operated nuclear plants currently operating in the USA. I am simply raising the concern (though some may accuse me of fear-mongering. BTW, perhaps it is the constant fear-mongering and vigilance that causes the nuclear power to be AS safe as it is?).
Percy writes:
The difference in opinion on power options has a strong emotional core deriving from the fact that nuclear plants pollute through accident and catastrophe while other options pollute through normal operation.
Good words, but this may not be specifically true with all types of Hydro power.

This message is a reply to:
 Message 132 by Percy, posted 03-20-2011 8:15 AM Percy has seen this message but not replied

Replies to this message:
 Message 138 by Rahvin, posted 03-21-2011 2:01 PM dronestar has not replied

  
DBlevins
Member (Idle past 3852 days)
Posts: 652
From: Puyallup, WA.
Joined: 02-04-2003


Message 137 of 175 (609571)
03-21-2011 1:50 PM
Reply to: Message 133 by Percy
03-20-2011 9:50 AM


Re: Question about Nuclear Plant Design
Are nuclear power plant containment facilities designed to maintain integrity if something like this were to happen directly beneath them?
IIRC the NP industry (at least in the U.S.) is under regulations that do not allow building too close to active faults. I am not sure what is considered a safe distance, and I am not sure what the tsunami regulations might be. (San Clemente comes to mind)

This message is a reply to:
 Message 133 by Percy, posted 03-20-2011 9:50 AM Percy has seen this message but not replied

  
Rahvin
Member
Posts: 4046
Joined: 07-01-2005
Member Rating: 5.3


Message 138 of 175 (609575)
03-21-2011 2:01 PM
Reply to: Message 136 by dronestar
03-21-2011 1:16 PM


Re: Information
I've done a lot of reading about Fukushima, nuclear power, and other power sources lately. It seems one needs an advanced education about any/each/all of them to talk with a degree of accuracy so I hesitate to offer additional information:
As you have alluded in your post, according to the following article, the term "spent" fuel rods are not really spent:
Your article is rather dumbed-down, and it makes a very pointed implication that the nuclear industry is being dishonest to the public regarding spent fuel, when such dishonesty has never existed.
The "hot" nature of spent fuel is why there's such a large amount of effort put into things like long-term storage in the first place (if the stuff wasn't still radioactive, we wouldn't need cooling pools or projects like Yucca Mountain, now would we). "Spent" in the context of nuclear fuel simply means "no longer suitable for a controlled fission reaction."
Generally, that means that the fuel rods are too contaminated with the products of nuclear fission to maintain a stable level of output.
But the spent fuel still contains a very large amount of radioactive material - in fact, that's exactly why reprocessing is so valuable. 95% of the potential energy output of a given fuel rod is still there when it is "spent," and reprocessing allows us to recover that still very usable fuel.
But even in reprocessed fuel, the waste still contains radioactive isotopes - and radiological decay generates waste heat. Spent fuel is hot - literally. In the case of the freshly-used fuel in the cooling pools at Fukushima, it's very hot, generating an estimated several megawatts (1-5 are the estimates I've heard) of waste heat, which is why it needed to be cooled in the first place.
I am unsure if there are similarly designed and operated nuclear plants currently operating in the USA. I am simply raising the concern (though some may accuse me of fear-mongering. BTW, perhaps it is the constant fear-mongering and vigilance that causes the nuclear power to be AS safe as it is?).
Percy writes:
The difference in opinion on power options has a strong emotional core deriving from the fact that nuclear plants pollute through accident and catastrophe while other options pollute through normal operation.
Good words, but this may not be specifically true with all types of Hydro power.
Thanks for weighing in Percy, although maybe your post (and mine) would have been better in the other "is nuclear safe" thread.
I've done a lot of reading about Fukushima, nuclear power, and other power sources lately. It seems one needs an advanced education about any/each/all of them to talk with a degree of accuracy so I hesitate to offer additional information:
As you have alluded in your post, according to the following article, the term "spent" fuel rods are not really spent:
Spent is an industry-euphemism. It implies something harmless, wasted or used up. Quite the opposite.
Spent fuel is irradiated fuel: fuel that has been irradiated inside a nuclear reactor’s core. After removal from the reactor, this fuel is massively contaminated with radioactive elements and must be stored in giant pools.
On March 15 the New York Times said these fuel pools could pose an even greater danger than the reactors melting down.
An even greater danger? Isn’t a core meltdown as bad as it gets?
Alas, a fuel pool meltdown could be worse than a reactor core meltdown. Much worse. This is because fuel pools contain far more radioactivity than that which is inside a reactor core. Unfortunately, at Fukushima we may get both types of meltdowns.
Robert Alvarez, formerly of the US Department of Energy and now at the Institute of Policy Studies, provided insight into this potential nuclear Armageddon. In a recent blog Alvarez states the fuel in each of the pools at the Fukushima complex has 5 to 10 times the radioactivity of the fuel inside one reactor core. And much of this radioactive material is the highly toxic and long-lived radionuclide, cesium-137. See.)
Another problem: Unlike the reactor cores, which have a hefty, six-inch thick steel containment vessel, the fuel pools at Fukushima are in unhardened and therefore highly vulnerable concrete structures. The roof of one of these structures has been completely demolished in at least one of the stricken reactors, Unit 4.
Why is irradiated fuel sitting in pools? (They’re sort of like swimming pools, though considerably deeper. About 40 feet long, 40 feet wide and 45 feet deep.)
After removal from the reactor core, the irradiated fuel is fiendishly hot. The fuel is so hot it will cause the water it is immersed in to boil — if the water is not cooled. What if fuel pool’s cooling systems fail? Disaster. If the water is not cooled for a certain number of days or weeks, the water will boil off. Next, the fuel can catch fire, releasing its toxic load to the environment.
Japan’s Nuclear Armageddon and the Experts « Aletho News
I am unsure if there are similarly designed and operated nuclear plants currently operating in the USA. I am simply raising the concern (though some may accuse me of fear-mongering. BTW, perhaps it is the constant fear-mongering and vigilance that causes the nuclear power to be AS safe as it is?).
A certain amount of fear is appropriate - when dealing with commercial power generation, every method needs to be treated with a certain degree of fear and respect.
The only nuclear regulations in the US that I particularly have a problem with are the executive orders against using nucelar fuel reprocessing, because it needlessly causes us to put out more waste than we need to, go through fuel far faster than we need to by wasting 95% of it, and to generate a larger proportion of high-grade waste as opposed to less-dangerous low-grade waste.
The fearmongering takes over when we have NIMBYs who decry projects like Yucca Mountain or lobby against new plant construction entirely. Fearmongering takes over when people take a nuclear crisis drastically out of proportion and oppose nuclear power on general principle, despite direct and objective evidence showing that it is orders of magnitude safer than any other method of generation per unit of power generated. Fearmongering takes over when people forget that you get a higher dose of radiation exposure from eating a banana than living a few miles from a nuclear plant for a year. Fearmongering takes over when people look at the dangers of nuclear power without even considering the relative dangers of all the other methods of power generation.
You know what I hate? Assumptions. I hate it when people assume that "clean renewables" like solar and wind power are somehow "safe" just because they can't explode. I hate when people don;t even bother to look up the facts (the numbers I've been posting I found in less than ten minutes with Google, anyone with a brain can find the same information if they bother) and just claim that "x is safer" without actually knowing any such thing.
There are people who honestly believe that nuclear power is the most dangerous form of power generation there is. Jon, on this very forum, said that nuclear was "stupid" and that no civilized society should ever use it - which means he didn't know a goddamned thing about nuclear (or any other) power other than it scares him more than other forms.
That's fearmongering - when you don;t base your fear on the actual facts and real relative risks involved, but rather make assumptions based on ignorance and create a completely irrational risk assessment that's 100% divorced from reality.
Percy writes:
The difference in opinion on power options has a strong emotional core deriving from the fact that nuclear plants pollute through accident and catastrophe while other options pollute through normal operation.
Good words, but this may not be specifically true with all types of Hydro power.
Not just hydro. Solar and wind don't pollute so much per se, but their dangers come from accidents as well.
To paraphrase the Joker from the Dark Knight - if 50 people die in a hydroelectric plant, nobody gets scared, because it's all part of the plan. If a natural gas line explodes, people say "wow, that's awful," but don;t protest natural gas heating or electricity because it's all part of the plan. Acid rain from coal plants, global warming, radioactive fly ash released directly into the air, nobody panics - because it's all part of the plan. It's not surprising, it's not shocking, it's just not scaryyou.
But if just a little teency bit of harmless levels of radiation leaks from a nuclear plant, even if nobody dies, everybody just loses their minds! No more nuclear! RADIATION IS BAD! OMG, radiation was found on spinach a few kilometers from Fukushima! Even though you'd need to ingest that level of radiation for a decade to see any harm, PANIC! PROTEST! LOUD NOISES!

This message is a reply to:
 Message 136 by dronestar, posted 03-21-2011 1:16 PM dronestar has not replied

  
jar
Member
Posts: 34046
From: Texas!!
Joined: 04-20-2004
Member Rating: 6.2


(1)
Message 139 of 175 (609576)
03-21-2011 2:01 PM


some areas of concern.
Speaking now about US power plants specifically.
We have several units that are cooled using piped water from a lower aquifer. I do not believe any of them (specifically the ones in coastal Maryland and Virginia) have secondary water supply facilities. Should something disrupt the pumping from the aquifers not only would there be direct and immediate effects, but we also now have opened pathways to pollute the aquifers themselves.

Anyone so limited that they can only spell a word one way is severely handicapped!

  
Rahvin
Member
Posts: 4046
Joined: 07-01-2005
Member Rating: 5.3


Message 140 of 175 (609580)
03-21-2011 2:18 PM
Reply to: Message 133 by Percy
03-20-2011 9:50 AM


Re: Question about Nuclear Plant Design
Are nuclear power plant containment facilities designed to maintain integrity if something like this were to happen directly beneath them?
Nuclear power plants, like other structures, are designed to withstand earthquakes of a given severity. The Fukushima plant was designed with up to a 7.8 quake in mind, because up to 7.3 quakes had been recorded historically in the area. Remember, the Richter scale is exponential, not linear, so they were designing with an extremely large margin of safety beyond what they anticipated was likely to occur in the area.
What actually happened was a 9.0. And again, the reactors did hold up to the quake, well outside of their design specification, very well. If the quake alone had happened, the nuclear power plant would in all likelihood be a non-issue. The containment breaches that eventually happened were not caused during the quake, but rather by pressure buildups and hydrogen explosions after the tsunami took the active coolant systems offline.
So while I'm not a structural engineer and I don't fully understand all the measures taken for earthquake safety, I'd say with decent confidence that, if a plant can take a 9.0 earthquake, one of the strongest on record ever, and keep ticking, you probably don't need to worry so much about earthquake damage.
Tsunamis, on the other hand...

This message is a reply to:
 Message 133 by Percy, posted 03-20-2011 9:50 AM Percy has replied

Replies to this message:
 Message 146 by Percy, posted 03-21-2011 4:38 PM Rahvin has not replied

  
Taq
Member
Posts: 10155
Joined: 03-06-2009
Member Rating: 4.8


Message 141 of 175 (609585)
03-21-2011 2:40 PM
Reply to: Message 133 by Percy
03-20-2011 9:50 AM


Re: Question about Nuclear Plant Design
Here's a question based upon this picture of a post-earthquake road in Japan:
From all appearances, that picture seems to depict a slump in the hillside. I would think that a large nuclear facility would need firm foundations and not be precariously perched on a hill side. Of course, I would also think that back up generators for a seaside nuclear facility would not be placed in the basement in a country where tsunamis are known to occur.

This message is a reply to:
 Message 133 by Percy, posted 03-20-2011 9:50 AM Percy has seen this message but not replied

  
Taq
Member
Posts: 10155
Joined: 03-06-2009
Member Rating: 4.8


Message 142 of 175 (609586)
03-21-2011 2:47 PM
Reply to: Message 135 by Rahvin
03-21-2011 12:55 PM


Re: Unexpected Tsunami??
Earthquakes in the range of 7-7.3 were expected, and the plant complex was designed with that in mind.
That isn't true. Japan has experienced several earthquakes in the 8.0 range in the last century. At wiki they list an 8.5 in 1896 and an 8.3 in 1923, both on the Richter scale. There are others of the same or greater magnitude in other scales. If they designed for 7-7.3 then they set the bar much lower than very recent earthquakes. There was also a magintude 8.2 quake in 1968 that was also accompanied by a large tsunami.
Edited by Taq, : No reason given.

This message is a reply to:
 Message 135 by Rahvin, posted 03-21-2011 12:55 PM Rahvin has replied

Replies to this message:
 Message 143 by Rahvin, posted 03-21-2011 3:08 PM Taq has replied

  
Rahvin
Member
Posts: 4046
Joined: 07-01-2005
Member Rating: 5.3


(1)
Message 143 of 175 (609592)
03-21-2011 3:08 PM
Reply to: Message 142 by Taq
03-21-2011 2:47 PM


Re: Unexpected Tsunami??
That isn't true. Japan has experienced several earthquakes in the 8.0 range in the last century. At wiki they list an 8.5 in 1896 and an 8.3 in 1923, both on the Richter scale. There are others of the same or greater magnitude in other scales. If they designed for 7-7.3 then they set the bar much lower than very recent earthquakes.
Where in Japan did those other quakes strike? Was it the same fault? If so you have a point, if not then you don't.
There was also a magintude 8.2 quake in 1968 that was also accompanied by a large tsunami.
The placement of the diesel generators was stupid. Other than the flooding of the backup generators, the facility held up to the tsunami as well. Solution: maybe don't locate all of your backup diesel generators below sea level.

This message is a reply to:
 Message 142 by Taq, posted 03-21-2011 2:47 PM Taq has replied

Replies to this message:
 Message 144 by jar, posted 03-21-2011 3:35 PM Rahvin has not replied
 Message 145 by Taq, posted 03-21-2011 3:44 PM Rahvin has not replied

  
jar
Member
Posts: 34046
From: Texas!!
Joined: 04-20-2004
Member Rating: 6.2


Message 144 of 175 (609597)
03-21-2011 3:35 PM
Reply to: Message 143 by Rahvin
03-21-2011 3:08 PM


Re: Unexpected Tsunami??
Lesson, don't locate mission critical equipment in any single location.

Anyone so limited that they can only spell a word one way is severely handicapped!

This message is a reply to:
 Message 143 by Rahvin, posted 03-21-2011 3:08 PM Rahvin has not replied

  
Taq
Member
Posts: 10155
Joined: 03-06-2009
Member Rating: 4.8


(1)
Message 145 of 175 (609599)
03-21-2011 3:44 PM
Reply to: Message 143 by Rahvin
03-21-2011 3:08 PM


Re: Unexpected Tsunami??
Where in Japan did those other quakes strike? Was it the same fault? If so you have a point, if not then you don't.
That is the same question that hit me after I posted it. Did some additional research. Turns out, I do have a point.
The 1933 Sanriku earthquake occurred 100 miles further out but pretty much in the same area. It produced a tsunami that struck the NE coast where Fukushima is currently.
1933 Sanriku earthquake - Wikipedia
The location of Fukushima can be seen here:
Fukushima (city) - Wikipedia
The 1896 earthquake seems to have been from the same subduction zone as the most recent one and it measured around a 7.2 followed by a massive tsunami.
Given the numerous 8.0+ quakes around the entire region I think it is a bit short sighted to design for 7.3. Of course, we both agree on the poor placement of the generators. In the end, the reactors handled the quake just fine, so this is more of an aside. However, if anything they should have planned way better for the tsunami given the two massive tsunamis that hit in 1896 and 1933 along the NE coast of Japan.

This message is a reply to:
 Message 143 by Rahvin, posted 03-21-2011 3:08 PM Rahvin has not replied

  
Percy
Member
Posts: 22605
From: New Hampshire
Joined: 12-23-2000
Member Rating: 4.9


Message 146 of 175 (609608)
03-21-2011 4:38 PM
Reply to: Message 140 by Rahvin
03-21-2011 2:18 PM


Re: Question about Nuclear Plant Design
Hi Rahvin,
I think you're answering a different question than the one I was asking. I wasn't asking if nuclear containment facilities are built to withstand a quake severe enough to cause ground faults like the ones in that photograph. I was asking if nuclear containment facilities are built to withstand ground faults like that occurring directly beneath them. Seems like a nearly impossible design problem, so I thought I'd ask.
--Percy

This message is a reply to:
 Message 140 by Rahvin, posted 03-21-2011 2:18 PM Rahvin has not replied

  
Percy
Member
Posts: 22605
From: New Hampshire
Joined: 12-23-2000
Member Rating: 4.9


Message 147 of 175 (609702)
03-22-2011 12:54 PM


Elite Parking Space
--Percy

Replies to this message:
 Message 148 by jar, posted 03-22-2011 1:00 PM Percy has seen this message but not replied

  
jar
Member
Posts: 34046
From: Texas!!
Joined: 04-20-2004
Member Rating: 6.2


Message 148 of 175 (609703)
03-22-2011 1:00 PM
Reply to: Message 147 by Percy
03-22-2011 12:54 PM


Re: Elite Parking Space
quote:
brinksmanship
--Percy??

Anyone so limited that they can only spell a word one way is severely handicapped!

This message is a reply to:
 Message 147 by Percy, posted 03-22-2011 12:54 PM Percy has seen this message but not replied

  
Percy
Member
Posts: 22605
From: New Hampshire
Joined: 12-23-2000
Member Rating: 4.9


(1)
Message 149 of 175 (609704)
03-22-2011 1:04 PM


Robot Question
I see many comments in the news about the lack of close-up information about containment facilities and cooling ponds. This seems an ideal application for robots. Images, videos, temperature readings, radioactivity measurements, it seems like robots should be able to provide all of these types of things, yet I see no mention of robots.
I just now decided I should Google the topic before sending this out and discovered I'm not the first to ask this question: Where are the robots in Japan's nuclear crisis?
It came out a couple days ago, talks about some of the possible robot alternatives.
--Percy

Replies to this message:
 Message 150 by fearandloathing, posted 03-22-2011 1:54 PM Percy has replied
 Message 151 by jar, posted 03-22-2011 2:06 PM Percy has seen this message but not replied

  
fearandloathing
Member (Idle past 4221 days)
Posts: 990
From: Burlington, NC, USA
Joined: 02-24-2011


Message 150 of 175 (609708)
03-22-2011 1:54 PM
Reply to: Message 149 by Percy
03-22-2011 1:04 PM


Re: Robot Question
Percy writes:
I see many comments in the news about the lack of close-up information about containment facilities and cooling ponds. This seems an ideal application for robots. Images, videos, temperature readings, radioactivity measurements, it seems like robots should be able to provide all of these types of things, yet I see no mention of robots.
I just now decided I should Google the topic before sending this out and discovered I'm not the first to ask this question: Where are the robots in Japan's nuclear crisis?
It came out a couple days ago, talks about some of the possible robot alternatives.
--Percy
I thought the same thing in an earlier post 4 days ago, msg 128 in this discussion. It seems like there should be more ROV's available to do dangerous stuff in many industries.
Here in the USA at least, we should look at having a highly trained group that can respond to emergencies like Japan is having. Hopefully it never will but if you roll dice long enough....
Maybe it could be paid for a tax put on nuclear or even a broader group of dangerous industries? Just a thought.
Edited by fearandloathing, : No reason given.
Edited by fearandloathing, : No reason given.

This message is a reply to:
 Message 149 by Percy, posted 03-22-2011 1:04 PM Percy has replied

Replies to this message:
 Message 160 by Percy, posted 03-29-2011 3:54 PM fearandloathing has not replied

  
Newer Topic | Older Topic
Jump to:


Copyright 2001-2023 by EvC Forum, All Rights Reserved

™ Version 4.2
Innovative software from Qwixotic © 2024