THE Nuclear Power Thread pt 5 (merged)

[outcast]

Thanks Tanada, interesting stuff. One thing I wondered when reading your post was, why doesn't the US reprocess the waste in the way the French do? I spose it's expensive?

Not only is it expensive, but the Carter administration put a stop to it because of fears about nuclear proliferation, or so I've heard anyway.

[Dezakin]

Thanks Tanada, interesting stuff. One thing I wondered when reading your post was, why doesn't the US reprocess the waste in the way the French do? I spose it's expensive?

Not only is it expensive, but the Carter administration put a stop to it because of fears about nuclear proliferation, or so I've heard anyway.

It was just politics, and bad politics at that. While it is possible to make a nuclear weapon from reactor grade plutonium, its a poor weapon that can be better fielded with actual weapons production reactors. If a country wants clandestine weapons production, they dont divert reactor spent fuel, they build production reactors or enrichment capacity.

Reprocessing isn't a great idea because uranium is so cheap, but its not a terrible idea because even with the 600% premium, it has nearly no effect on the cost of electricity from nuclear power. I don't recommend it because spent fuel allready takes up nearly no space and you're complicating a fuel cycle for political concerns. The opponents of nuclear power aren't going to care if you reprocess or not, their opposed either way, and people that understand the fuel cycle realize that it doesn't contribute much. So for me its just a giant waste of time, but not really worth the effort to prevent.

[SeaGypsy]

From the Wikipedia page on Nuclear Decommissioning:

Experience
See also: List of nuclear reactors

A wide range of nuclear facilities has been decommissioned so far. This includes nuclear power plants (NPPs), research reactors, isotope production plants, particle accelerators, uranium mines etc. However, the number of decommissioned power plants is fairly small. There are companies specialized in nuclear decommissioning; the practice of decommissioning has turned into a profitable business. Decommissioning is very expensive; the current estimate by the United Kingdom's Nuclear Decommissioning Authority is that it will cost at least £70 billion to decommission the existing United Kingdom nuclear sites; this takes no account of what will happen in the future. Also, due to the latent radioactivity in the reactor core, the decommissioning of a reactor is a slow process which has to take place in stages; the plans of the Nuclear Decommissioning Authority for decommissioning reactors have an average 50 year time frame. The long time frame makes reliable cost estimates extremely difficult. Excessive cost overruns are not uncommon even for projects done in a much shorter time.

and...

Cost of decommissioning

In USA many utilities estimates now average $325 million per reactor all-up (1998 $).

In France, decommissioning of Brennilis Nuclear Power Plant, a fairly small 70 MW power plant, already cost 480 millions euros (20x the estimate costs) and is still pending after 20 years. Despite the huge investments in securing the dismantlement, radioactive elements such as Plutonium, Cesium-137 and Cobalt-60 leaked out into the surrounding lake.[63] [64]

In the UK, decommissioning of Windscale Advanced Cooled Reactor (WAGR), a 32 MW power plant, cost 117 millions euros.

In Germany, decommissioning of Niederaichbach nuclear power plant, a 100MW power plant, cost about 90 millions euros.

[edit] (Lack of) Decommissioning Funds

In Europe there is considerable concern on the funds necessary to finance final decommissioning. In many countries either the funds do not appear sufficient to pay the financial decommissioning, and in other countries the (substantial) funds are being used (too) freely for activities other than decommissioning, putting the funds at risk, and distorting competition with parties who do not have nuclear decommissioning funds available.[65]

Currently (2008) the European Commission is looking into this issue.


This goes to the main points of concern to me. Costs and timing of decommissioning at a time when economic calamity is growing with no end in sight.

I am nowhere near as well read as Tanada on the other issues involved in nuclear power& I do agree he has a lot of very good arguments for nuclear power as a transition fuel.

The problem as I see it is the dependency of decommissioning on a social, cultural& political continuum. I am not convinced this continuum will happen.

I am also not convinced the signage is adequate warning to future generations.

[Tanada]

[quote=From the Wikipedia page on Nuclear Decommissioning:]

Experience
See also: List of nuclear reactors

A wide range of nuclear facilities has been decommissioned so far. This includes nuclear power plants (NPPs), research reactors, isotope production plants, particle accelerators, uranium mines etc. However, the number of decommissioned power plants is fairly small. There are companies specialized in nuclear decommissioning; the practice of decommissioning has turned into a profitable business. Decommissioning is very expensive; the current estimate by the United Kingdom's Nuclear Decommissioning Authority is that it will cost at least £70 billion to decommission the existing United Kingdom nuclear sites; this takes no account of what will happen in the future. Also, due to the latent radioactivity in the reactor core, the decommissioning of a reactor is a slow process which has to take place in stages; the plans of the Nuclear Decommissioning Authority for decommissioning reactors have an average 50 year time frame. The long time frame makes reliable cost estimates extremely difficult. Excessive cost overruns are not uncommon even for projects done in a much shorter time.

and...

Cost of decommissioning

In USA many utilities estimates now average $325 million per reactor all-up (1998 $).

In France, decommissioning of Brennilis Nuclear Power Plant, a fairly small 70 MW power plant, already cost 480 millions euros (20x the estimate costs) and is still pending after 20 years. Despite the huge investments in securing the dismantlement, radioactive elements such as Plutonium, Cesium-137 and Cobalt-60 leaked out into the surrounding lake.[63] [64]

In the UK, decommissioning of Windscale Advanced Cooled Reactor (WAGR), a 32 MW power plant, cost 117 millions euros.

In Germany, decommissioning of Niederaichbach nuclear power plant, a 100MW power plant, cost about 90 millions euros.

[edit] (Lack of) Decommissioning Funds

In Europe there is considerable concern on the funds necessary to finance final decommissioning. In many countries either the funds do not appear sufficient to pay the financial decommissioning, and in other countries the (substantial) funds are being used (too) freely for activities other than decommissioning, putting the funds at risk, and distorting competition with parties who do not have nuclear decommissioning funds available.[65]

Currently (2008) the European Commission is looking into this issue.

This goes to the main points of concern to me. Costs and timing of decommissioning at a time when economic calamity is growing with no end in sight.

I am nowhere near as well read as Tanada on the other issues involved in nuclear power& I do agree he has a lot of very good arguments for nuclear power as a transition fuel.

The problem as I see it is the dependency of decommissioning on a social, cultural& political continuum. I am not convinced this continuum will happen.

I am also not convinced the signage is adequate warning to future generations.

Alright so it seems to me that 90% of your concern falls into the realm of pollitics, the powers that be are squandering decomissioning money on other projects, some sites were not properly regulated when they were being run and therefore are more expensive to remediate than they should have been and so on. The best I can offer you about this problem is, because of the compact size of an NPP even if nothing were done to decomission it the plant does not take up much space ibn a geographical sense. From the day the fuel is pulled out of the core and forever after the radiation level of the reactor vessel and the containment structure is decreasing and will continue doing so.

The dirty little secret of the Anti-nuclear movement is thus, the longer a material is radioactive the LESS dangerous it is. They constantly reverse this in their statements, but that does not make it true. The key to radiation damage is dose rate, IOW the faster you are exposed the harder it is for your body to repair itself. The really dangerous period for spent fuel is the first three years after removal from the reactor. By the end of a decade it is relatively safe to handle, but you should limit your exposure. By the end of a century the dose rate is moderate and by the end of 6 centuries the spent fuel is about as dangerous as living in Quito, Ecuador where the natural background radiation is 7 times that of living at sea level in the Phillippines. The variabillity of background radiation on Earth is far greater than 99.9% of the population appreciate. The vast majority of the Chernobyl exclusion zone is less radioactive that places like Ramsar, Iran where people have lived for thousands of years without ill effects, higher cancer rates, or any other abnormallity. At an nuclear facillity you are going to decomission Spent Nuclear Fuel is the most intensly radioactive, which is why I tent to focus on it. If your protection keeps you safe from the spent fuel then it keeps you safe from everything else in the plant as well.

No matter if they realize it or not people live in a radioactive world, the concrete goundation of your home, the wood used in its construction, the food you eat and the water you drink and bathe in are all emitting radiation all the time. A closed and defueled NPP is radioactive, but that radioactivity is 99% confined to the containment building and reactor vessel. Given that the containment structure is almost always made of concrete the fact that it is radioactive is no surprise at all. Saying it is three times as radioactive as 'normal' concrete sounds scary until you realize that it still doesn't add up to much of a dose rate.

You said somewhere or other that you live in the Phillippines and commute to Australia frequently on bussiness/work by air. Every 14 hours you spend flying gives you the same radiation dose you get from living in a concrete building for a full year. Does 'radioactive' concrete with 'three times the normal radioactivity' sound scary when you get the same effective dose by flying for 42 hours over the span of a year?

The same is more or less true for the steel reactor vessel at the heart of the containment building, yes it is radioactive and yes it is more radioactive than fresh steel from newly mined iron ore. But does that mean it gives of dangerous levels of radioactivity?
Look at

3.2 Demolition of the building to green meadow
• The project took a period of 4 years;
• Total costs were about 3 million (2003) Euros;
• About 1650 tons of material has been removed (0,5 %
radioactive waste; 0,5 % conventional waste; 99 % for reuse
purposes);
• For about 40 tons lightly activated scrap (60Co levels between
0,01 and 10 Bq/g) a cost effective solution still is looked for. In
fact, the scrap below 1 Bq/g is no radioactive waste. But, it is not
accepted by the recycling industry (it is detected by the entrance
monitors), and according to Netherlands regulations, a licence is
needed to store it on a conventional refuse dump;

which is from LINK

They have 40 tons of lightly activated steel scrap left over, all of it with a dose rate below 10 Becquerel's per gram. Steel with a dose rate of less than 1 Bq/g is considered non-radioactive. Because of the paranoia of the government's of Europe the allowed dose rate is so low that this very low dose rate material is rejected because the rate is detectible. The common sense solution would be to mix this 40 tons with 1000 tons of fresh iron, if you did that the total effective dose rate would fall to 4% of the current very low rate, IOW even if it were all 10 Bq/g the mixture would be .0038 Bq/g, which is so low it is hard to detect compared to all the other sources surrounding you. Because of pollitics this solution is not allowed, no matter how eminently sensible it is.

The biggest problem the NPP industry has is the public perceptions of Radiation and the consequent reactions of the polliticians to the word. Driving a car made of 10 Bq/g dose rate steel would give you a lower dose rate than spending the same amount of time sitting in front of an old fashioned picture tube TV set, and far less than a picture tube based Computer monitor gives you, but people never think about the dose they are getting from using a computer or watching TV.

[SeaGypsy]

Well Tanada, I compliment you once more on your research and thank you for this post. I am sure you have the best of intentions.

Let me ask again; what happens if there is a financial, political and social meltdown? Who will clean up the mess? Who will know how to clean it up safely if the knowledge is lost aka Library of Alexandria?

If there is enough of a break in continuum, how would people , know not to use the materials or live in them? (from the core parts of the reactor?)
Or do we think that is not important enough to think about?

At the very least I would like to see that this rates as highly important for emergency planning of the generating states, as well as an emergency relabeling of all poisons if the state is failing and unable to properly dispose of dangerous materials.

I agree with your points on background radiation and politics preventing infinitely better storage for toxic wastes; it is disgusting this kind of stuff is left in stacked barrels behind a fence when people have devoted their lives to figuring safe methods.

In Australia, politics just forced a dump to be built; to move from a solid rock spot in South Australia to a Limestone water table directly connected to the Great Artesian Basin which provides most of the water for outback Australia.

[Tanada]

Well Tanada, I compliment you once more on your research and thank you for this post. I am sure you have the best of intentions.

1Let me ask again; what happens if there is a financial, political and social meltdown?2 Who will clean up the mess?3 Who will know how to clean it up safely if the knowledge is lost aka Library of Alexandria?

4If there is enough of a break in continuum, how would people , know not to use the materials or live in them? (from the core parts of the reactor?)
5Or do we think that is not important enough to think about?

At the very least I would like to see that this rates as highly important for emergency planning of the generating states, as well as an emergency relabeling of all poisons if the state is failing and unable to properly dispose of dangerous materials.

I agree with your points on background radiation and politics preventing infinitely better storage for toxic wastes; it is disgusting this kind of stuff is left in stacked barrels behind a fence when people have devoted their lives to figuring safe methods.

In Australia, politics just forced a dump to be built; to move from a solid rock spot in South Australia to a Limestone water table directly connected to the Great Artesian Basin which provides most of the water for outback Australia.

I numbered your questions above so that I wouldn't get confused giving my answers.
1) Well it all depends on how bad the melt down gets, do we fall back to 1950, or 1850, or 1750? I don't think we would fall any further than 1750 in the worst case scenario, there is simply too much refined metal available for the survivors to use to keep the Iron age going. 1850 level with coal power is very likely as well because it is such a common resource in many countries. 1950 is my best case scenario, we keep electricity and hence the ability to use nuclear fission power as an active power supply.

2) if we have a complex society that wants to clean up the 'mess' as you call it from NPP then even with 1750 technology they can do it. All they have to do is seal the entrances to the containment building with bricks and mortar, then bury the whole thing with dirt to make an artificial hill. Doing it with 1850 tech would mostly mean sealing the entry ways with concrete instead of bricks, but the result is the same, nobody can get in. For 1950 using machinery to scrap it out is pretty much the same as it is today in terms of heavy demolition work.

3) Given the millions of books existing in millions of places the situation even if we went into a new dark age like Europe from 650-1450 there would still be a lot of copies of the relevant books here or there. Even barring that, the half lives of the radioactive materials in question in the Concrete and Steel is are in the 5-8 year range. That means in 40 years the radiation is 1/32nd of what it was the day the reactor shut off.

4) If you get your break in the continuum period the radiation will have dissipated by the time our distant descendents start recycling reactor cores, there are a lot of much easier supplies of iron and steel available from cars/trucks/heavy equipment. You need either a very large fire to melt the core containment steels into smaller pieces or some pretty significant machinery to lift it out in one or two very large, very heavy pieces. These things are built like Battleship armor, the metal is 15+ cm thick at its thinnest spots. No primitive is going to be sawing off a piece to make a spear point, and by the time primitives are running around in large enough numbers to get it apart the radiation will have dissipated.

5) I do think it is important enough so I spent a lot of time learning about it and thinking about it. I am now convinced that compared to other remnants of our civilization we are leaving behind it is a very very small concern. In 80 years there is effectively no radiation left (its called the 10 half life rule, each half life halves the dose rate and after 10 half lives you get 50%, 25%, 12.5%, 6.25%, 3.125%, 1.625%, 0.8125%
0.40625%, 0.203125%, 0.1015625%. Clearly from the series you can see after 5 half lives what is left is almost nothing, unless the material was a huge quantity it is harder and harder to even detect.

That 40 tons of scrap metal that was max 10 Bq dose rate I pointed you too earlier? In 25 years the dose rate will be 0.625 Bq. Radioactive materials radiate and become inert. The shorter the half life the more dangerous they are on day 1 and the faster they become inert.

[SeaGypsy]

Thanks Tanada,
while you are at it can you please post links to information supplied here on half lives?
You are certainly a very skilled defender of nuclear power; may I ask if you work in the industry without being offensive?
If not I am sure you would have no trouble at all finding a job!
It is a pleasure to meet such a thoroughly researched argument, I would like to see some links though.

[oiless]

Tanada, I don't know enough about it to argue, I'm just trying to make sense of it:

Here you say: "That 40 tons of scrap metal that was max 10 Bq dose rate I pointed you too earlier? In 25 years the dose rate will be 0.625 Bq. Radioactive materials radiate and become inert. The shorter the half life the more dangerous they are on day 1 and the faster they become inert"

So a fairly short half life, implying fairly high radiation?
I suspect processing the scrap could be expensive, flame cutting and so on create lots of air born particles, which will probably require precautions. (Unless it's done in some third world country.) Is 40 tons realistic? From what I understand a lot of these core components are thick material.

Here you say:"Driving a car made of 10 Bq/g dose rate steel would give you a lower dose rate than spending the same amount of time sitting in front of an old fashioned picture tube TV set, and far less than a picture tube based Computer monitor gives you, but people never think about the dose they are getting from using a computer or watching TV."

So, low radiation dose, implying a long half life?

[Tanada]

Thanks Tanada,
while you are at it can you please post links to information supplied here on half lives?
You are certainly a very skilled defender of nuclear power; may I ask if you work in the industry without being offensive?
If not I am sure you would have no trouble at all finding a job!
It is a pleasure to meet such a thoroughly researched argument, I would like to see some links though.

Most of the radioactivity in the empty core comes from the steel, and most of the steel is made up of Iron with Nickle, Carbon and a few other things mixed in to make it strong and rust resistant. So here you go, these links are for the isotopes of Iron, Nickle and Cobalt, when a neutron from the reactror core hits iron or nickle you usually get one of these as a result.

Iron

Nickel

Cobalt

In particular Iron-55 has a half life of 2.73 years, and Cobalt-60 with a half life of 5.27 years. Almost every other isotope is either stable or so radioactive that it decays away in weeks.

Other than the metals in the rebar inside the concrete the material itself can also become 'activated' by the neutron flux, if you look at the table 5 on THIS DOCUMENT you can see that the radioactivity level is very low after a 10 year period, in this case the strongest emitter is the aggregate in the concrete. At discharge it emits 11,000 Bq/g and after 10 years it emits 660 Bq/g. That is a decrease in activation of 94% in ten years which unless I screwed up my math is five half lives or a half life of 2 years. Based on that in 20 years it will be down to 20 Bq/g and in 30 years after activation it is down to 0.64 Bq/g.

[Tanada]

Tanada, I don't know enough about it to argue, I'm just trying to make sense of it:

Here you say: "That 40 tons of scrap metal that was max 10 Bq dose rate I pointed you too earlier? In 25 years the dose rate will be 0.625 Bq. Radioactive materials radiate and become inert. The shorter the half life the more dangerous they are on day 1 and the faster they become inert"

So a fairly short half life, implying fairly high radiation?
I suspect processing the scrap could be expensive, flame cutting and so on create lots of air born particles, which will probably require precautions. (Unless it's done in some third world country.) Is 40 tons realistic? From what I understand a lot of these core components are thick material.

Here you say:"Driving a car made of 10 Bq/g dose rate steel would give you a lower dose rate than spending the same amount of time sitting in front of an old fashioned picture tube TV set, and far less than a picture tube based Computer monitor gives you, but people never think about the dose they are getting from using a computer or watching TV."

So, low radiation dose, implying a long half life?

If the half life is short the does rate is fast and vice versa. For example most activation isotopes around a core have a half life of 1 second or less, IOW in 10 seconds they have decay's away to insignificant levels, but if you are holding them when that happens you get a very high dose of radiation.

There are two ways to get a high dose rate, you have to be in contact with a small mass of very short half life or an X-ray camera, or you have to be completely surrounded by something that gives a moderate dose rate but which you are exposed too for a longer time.

In the example you refer to above the half life is about 2.73 years for Iron-55, however the iron in question has already been decaying for some years before it fell to 10 Bq/g. 2.73 years after you bought a car made out of it the dose rate would be 5 Bq/g, 5.46 years after purchase it would be 2.5 Bq/g and so on. It has already decayed for so long by that point that it is almost inert, In the USA regulations state that any material with less than 70 Bq/g is exempt from nuclear labelling because the dose rate is so low it is insignificant to anyone handling it. The metal in the above example was only at 10 Bq/g but the scrap dealers in the Netherlands refused to process it because of an insane fear of the word Radioactive.

[Dezakin]

I numbered your questions above so that I wouldn't get confused giving my answers.
1) Well it all depends on how bad the melt down gets, do we fall back to 1950, or 1850, or 1750? I don't think we would fall any further than 1750 in the worst case scenario, there is simply too much refined metal available for the survivors to use to keep the Iron age going. 1850 level with coal power is very likely as well because it is such a common resource in many countries. 1950 is my best case scenario, we keep electricity and hence the ability to use nuclear fission power as an active power supply.

I applaud your patience with these silly questions Tanada. I've honestly grown weary of the 'what do we do with used reactors in the ridiculous post apocalypse mad max world?' questions. In such a ludicrous scenario, toxic metal under tonnes of concrete aren't going to be the biggest survival concern.

We might as well ask what we're going to do with all the used fluorescent light bulbs.

[SeaGypsy]

I numbered your questions above so that I wouldn't get confused giving my answers.
1) Well it all depends on how bad the melt down gets, do we fall back to 1950, or 1850, or 1750? I don't think we would fall any further than 1750 in the worst case scenario, there is simply too much refined metal available for the survivors to use to keep the Iron age going. 1850 level with coal power is very likely as well because it is such a common resource in many countries. 1950 is my best case scenario, we keep electricity and hence the ability to use nuclear fission power as an active power supply.

I applaud your patience with these silly questions Tanada. I've honestly grown weary of the 'what do we do with used reactors in the ridiculous post apocalypse mad max world?' questions. In such a ludicrous scenario, toxic metal under tonnes of concrete aren't going to be the biggest survival concern.


Lets just put it under your place because someone dug up some very friendly numbers; I'm still waiting for the other side of this.

We might as well ask what we're going to do with all the used fluorescent light bulbs.

[Tanada]

Lets just put it under your place because someone dug up some very friendly numbers; I'm still waiting for the other side of this.

Gee Seagypsy, I thought you wanted numbers based on real physics, not something just made up by someone advocating a position? Guess I misunderstood your desire to know how the real physical world of radiation works.

[SeaGypsy]

Lets just put it under your place because someone dug up some very friendly numbers; I'm still waiting for the other side of this.

Gee Seagypsy, I thought you wanted numbers based on real physics, not something just made up by someone advocating a position? Guess I misunderstood your desire to know how the real physical world of radiation works.

You certainly know your stuff Tanada; I am not trying to insult your research; but to be effectively called a moron for asking the question?
(by Dezakin). Screw him/ her, riding on your tailcoat.
I am just saying that if there is someone who has thoroughly researched and came up with different answers to yourself; I would like to see them.

[bencole]

Lets just put it under your place because someone dug up some very friendly numbers; I'm still waiting for the other side of this.

Gee Seagypsy, I thought you wanted numbers based on real physics, not something just made up by someone advocating a position? Guess I misunderstood your desire to know how the real physical world of radiation works.

You certainly know your stuff Tanada; I am not trying to insult your research; but to be effectively called a moron for asking the question?
(by Dezakin). Screw him/ her, riding on your tailcoat.
I am just saying that if there is someone who has thoroughly researched and came up with different answers to yourself; I would like to see them.

Sea Gypsy, you are correct in voicing concern regarding nuclear industry activities and there potential environmental and health hazards. Despite the ideal picture the nuclear industry portrays regarding nuclear waste, radiation exposure, fuel reprocessing activites, reactor safety and other topics, if you dig deeper you'll find significant justification for concern. In spent nuclear fuel the elements neptunium 237 and plutonium 239 have half-lives of 2 million years and 24,000 years respectively, this is such a long period that it is almost impossible to construct a proper hydrogeology model that can determine whether or not this waste will eventually leak back into the biosphere in a long term storage arrangement like yucca mountain. There is continuing scientific debate over what constitutes a "safe" exposure threshold for radiation, its by no means certain, in theory even very low levels of radiation have the potential for unforseen genetic damage that can lead to increased instances of cancer and other diseases. Nuclear reprocessing activities are not entirely safe either, and there is a history of severe criticality accidents and other mishaps like fires and explosions where workers have been injured and killed due to massive radiation exposure. There are still serious questions regarding reactor safety as well, obvious examples are chernobyl of which there are several units of identical design still in operation, and three mile island type pressurized water reactors which could potentially be vunerable to loss of coolant type accidents is cases of severe negligence or sabotage. A potential failure mode can pretty much exist in any concievable design, failed coolant circulation pumps, jammed control rods, moderator fires and leaks, leaks in high pressure piping etc.

I just finished reading a pretty interesting scientific paper on nuclear accidents published by the DOE's Los Alamos lab, its a prettly long pdf and wordy but quite interesting:
http://www.orau.org/ptp/Library/accidents/la-13638.pdf

[Dezakin]

Lets just put it under your place because someone dug up some very friendly numbers; I'm still waiting for the other side of this.

Okay. It'd help keep my house warm in the winter.

[Dezakin]

Sea Gypsy, you are correct in voicing concern regarding nuclear industry activities and there potential environmental and health hazards. Despite the ideal picture the nuclear industry portrays regarding nuclear waste, radiation exposure, fuel reprocessing activites, reactor safety and other topics, if you dig deeper you'll find significant justification for concern. In spent nuclear fuel the elements neptunium 237 and plutonium 239 have half-lives of 2 million years and 24,000 years respectively, this is such a long period that it is almost impossible to construct a proper hydrogeology model that can determine whether or not this waste will eventually leak back into the biosphere in a long term storage arrangement like yucca mountain.

And uranium 238 has a half life of 4 billion years and is everywhere, not to mention heavy metal toxicity. Oh noes.

We don't need to plan for 10000 years in the future. Thats for future civilizations to worry about.

[bencole]

And uranium 238 has a half life of 4 billion years and is everywhere, not to mention heavy metal toxicity. Oh noes.

Some radioisotopes are more dangerous than others due to there potential mobility in the environment. Of particular concern is how mobile isotopes could potentially interact with ground water in deep geological repositories. Would you feel safe drinking a glass of water laced with Pu-239 and Np-237?

We don't need to plan for 10000 years in the future. Thats for future civilizations to worry about.

I'm sure that future generations would appreciate it if we left them a planet worth living on.

[SeaGypsy]

Sea Gypsy, you are correct in voicing concern regarding nuclear industry activities and there potential environmental and health hazards. Despite the ideal picture the nuclear industry portrays regarding nuclear waste, radiation exposure, fuel reprocessing activites, reactor safety and other topics, if you dig deeper you'll find significant justification for concern. In spent nuclear fuel the elements neptunium 237 and plutonium 239 have half-lives of 2 million years and 24,000 years respectively, this is such a long period that it is almost impossible to construct a proper hydrogeology model that can determine whether or not this waste will eventually leak back into the biosphere in a long term storage arrangement like yucca mountain.

And uranium 238 has a half life of 4 billion years and is everywhere, not to mention heavy metal toxicity. Oh noes.

We don't need to plan for 10000 years in the future. Thats for future civilizations to worry about.

This is more about phasing out and burying in the safest way possible something that scientists find exciting, biologists find frightening and philosophers impossible to justify.

It's not about just planning for the future it's about recognizing the damage we are doing by continuing with plans made in the past or present.

Can someone prove wrong an assertion going around in anti nuke circles that IF we pulled out all known uranium reserves applied EROEI to them the net gain is equivalent in energy to 4 months of current world use of oil? (Pre-Crash figure). If this one is true then it's a hell of a lot of unknowns projected into untold years ahead; for a measly gain. I would need to see far better returns by a factor of 10-100 to justify doing any of this Doctor Jekyll business. This besides the fact that continuing the industry perpetuates nuclear proliferation. (bombs, real big ones)

[Dezakin]

Sea Gypsy, you are correct in voicing concern regarding nuclear industry activities and there potential environmental and health hazards. Despite the ideal picture the nuclear industry portrays regarding nuclear waste, radiation exposure, fuel reprocessing activites, reactor safety and other topics, if you dig deeper you'll find significant justification for concern. In spent nuclear fuel the elements neptunium 237 and plutonium 239 have half-lives of 2 million years and 24,000 years respectively, this is such a long period that it is almost impossible to construct a proper hydrogeology model that can determine whether or not this waste will eventually leak back into the biosphere in a long term storage arrangement like yucca mountain.

And uranium 238 has a half life of 4 billion years and is everywhere, not to mention heavy metal toxicity. Oh noes.

We don't need to plan for 10000 years in the future. Thats for future civilizations to worry about.

This is more about phasing out and burying in the safest way possible something that scientists find exciting, biologists find frightening and philosophers impossible to justify.

It's not about just planning for the future it's about recognizing the damage we are doing by continuing with plans made in the past or present.

Can someone prove wrong an assertion going around in anti nuke circles that IF we pulled out all known uranium reserves applied EROEI to them the net gain is equivalent in energy to 4 months of current world use of oil? (Pre-Crash figure). If this one is true then it's a hell of a lot of unknowns projected into untold years ahead; for a measly gain. I would need to see far better returns by a factor of 10-100 to justify doing any of this Doctor Jekyll business. This besides the fact that continuing the industry perpetuates nuclear proliferation. (bombs, real big ones)

Is 500 good enough?

The Rossing mine produced 3037 tonnes of Uranium in 2004, which is sufficient for 15 GigaWatt-years of electricity with current reactors. The energy used to mine and mill this Uranium was about 3% of a GigaWatt-year. Thus the energy produced is about 500 times more than the energy required to operate the mine.