Educating the general public about pro nuclear energy?

In summary, some people fear nuclear power because of the Fukushima incident. However, the fear is not based on any factual information. The fear is based on media coverage that is biased and inaccurate.
  • #246
SredniVashtar said:
There you go:

""As for the wastes, that 3% that decays between 1000 and 10000 years [...] can you be sure they will be taken care of after all that time? Will you write instruction in English, Latin, Sumerian, Hieroglyphs or Linear A? Ten thousand years is a long time."

Awaiting a serious answer.
You're just reposting your [implied] claim, which has already been responded to, and ignoring the response you got. What I want a serious answer to is why you think it is necessary that we must assure *today* that it "be taken care of" for that amount of time.

As I said, due to your unserious previous response it isn't clear that you understood the objection you were given -- and now that you have ignored it completely.
 
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  • #247
"When we consider the longer-lived activities that might characterize spent fuel elements, we are interested in a time scale of the order of years. Figure 13.30 shows the activities of the long-lived fission products and actinides. After reprocessing, these activities must be isolated from biological systems for times of the order of 10^5-10^6 years. Several schemes have been suggested for achieving this isolation but no system has yet been adopted that can guarantee isolation over this time scale. Any leakage into groundwater or the food chain would be expected to result in an increase in deaths from cancer".

Kenneth Krane, "Introductory Nuclear Physics", 1988
A lot o time has passed, since then. Fast forward to february 2016, last update to the World Nuclear Association "Radioactive Wastes" page.

"The radioactivity of high-level wastes decays to the level of an equivalent amount of original mined uranium ore in between 1,000 and 10,000 years. Its hazard then depends on how concentrated it is.[...]
A small volume of nuclear waste (~3% volume of total waste produced) is long-lived and highly radioactive and requires isolation from the environment for many thousands of years.[...]
Waste is converted into a stable form that is suitable for disposal. In the case of high-level waste, a multi-barrier approach, combining containment and geological disposal, ensures isolation of the waste from people and the environment for thousands of years.[...]"

"Many people quite reasonably feel that the nuclear industry shouldn't continue operation without having a solution for the disposal of its radioactive waste. However, the industry has in fact developed the necessary technologies and implemented most of them[...]"
"Today, safe management practices are implemented or planned for all categories of radioactive waste. Low-level waste (LLW) and most intermediate-level waste (ILW), which make up most of the volume of waste produced (97%), are being disposed of securely in near-surface repositories [...]"
"High-level waste (HLW) is currently safely contained and managed in interim storage facilities.[...]
These facilities also allow for the heat and radioactivity of the waste to decay prior to long-term geological disposal.[...]
In the long-term however, appropriate disposal arrangements are required for HLW, due to its prolonged radioactivity. Disposal solutions are currently being developed for HLW that are safe, environmentally sound and publicly acceptable. The solution that is widely accepted as feasible is deep geological disposal,[...]"


So, my question still stands.
[edited by mod]
 
  • #248
SredniVashtar said:
...
So, my question still stands.
None of that was responsive to the answer/follow-up question you got. I think therefore that your answer is that you haven't put any thought into the question. What I'm not totally sure of is if you realize it and are dodging or really don't understand that there must be a "why". So I'll lay it out for you. It is two-pronged:

The US government does not have the responsibility to protect you completely from all dangers today(1), much less perpetually(2).

1. For all the protection we get from the US government, planes and cars still crash, buildings burn and collapse and people die from inhaling the pollutants of other sources of energy. The government is required to make a reasonable effort to make you pretty safe -- it is not required, nor is it even possible, to make you totally safe. If it were, we wouldn't be using lead or any other heavy metal at all; we'd be collecting and burying it all in the geological storage facilities.

2. If the US government ends and enough people and technology are destroyed throughout the world so that no one understands English anymore - civilization literally gets set back to the stone age - the responsibility of the US government will have ended. Indeed, at that point the US government will have already failed in its responsibility. Any additional harm potentially caused by someone digging up nuclear waste (or finding it in a warehouse) will pale in comparison to that larger failure. So it is illogical to try to plan for it. You could make the similar case that in 100 years my house will become so old that it is dangerous to live in. But if the US government has collapsed and people are back to the stone age and someone needs a roof, maybe they'll choose to live in it. And maybe it will collapse on them and kill them. That will be yet another failure of the US government to provide perpetual protection. Why aren't we planning for that?
 
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  • #249
SredniVashtar said:
So, my question still stands.

The quotes you partially reference from WNA are from a page on "myths and realities" about nuclear waste, a contrast not clear in the passage you quoted. In particular, you omitted parts of the reference which place radioactivity in context.

From the WNA reference, myth #5:
5. Nuclear wastes are hazardous for tens of thousands of years. This clearly is unprecedented and poses a huge threat to our future generations in the long-term
My take is your thesis in the above posts are summarized as myth #5 by WNA.

And the entire body of response #5:

Many industries produce hazardous waste. The nuclear industry has developed technology that will ensure its hazardous waste can be managed appropriately so as to cause no risk to future generations.

In fact, the radioactivity of nuclear wastes naturally decays progressively and has a finite radiotoxic lifetime. The radioactivity of high-level wastes decays to the level of an equivalent amount of original mined uranium ore in between 1,000 and 10,000 years. Its hazard then depends on how concentrated it is. Compare this to other industrial wastes (e.g. heavy metals such as cadmium and mercury), which remain hazardous indefinitely.

Most nuclear wastes produced are hazardous, due to their radioactivity, for only a few tens of years and are routinely disposed in near-surface disposal facilities. A small volume of nuclear waste (~3% volume of total waste produced) is long-lived and highly radioactive and requires isolation from the environment for many thousands of years.

International conventions define what is hazardous in terms of radiation dose, and national regulations limit allowable doses accordingly. Well-developed industry technology ensures that these regulations are met so that any hazardous wastes are handled in a way that poses no risk to human health or the environment. Waste is converted into a stable form that is suitable for disposal. In the case of high-level waste, a multi-barrier approach, combining containment and geological disposal, ensures isolation of the waste from people and the environment for thousands of years
[emphasis mine]

One area of agreement in all the above posts in this thread seems to be that nobody wants significant concentrations of radioactivity, cadmium, or mercury dumped into the food chain or water supply. This is different from suggesting a ban on radioactivity (or elements of the periodic table.)

Further, in your quote above from WNA on '3% volume', a sentence was clipped which I include here:
...Most nuclear wastes produced are hazardous, due to their radioactivity, for only a few tens of years and are routinely disposed in near-surface disposal facilities. A small volume of nuclear waste (~3% volume of total waste produced) is long-lived and highly radioactive and requires isolation from the environment for many thousands of years.
 
  • #250
Still the same logical fallacy: since there are other poisons, this poison is not poisonous.
Also, my quotes are referring to facts, not the myth part.
I understand that you would prefer to talk about the 97% short-lived part of the waste, but - for the n-th time - this is not what I am talking about. I am talking about the 3% long-lived part that according to Krane and the Wolrd Nuclear Association requires long term storage (stated as a fact, not a myth).

And the bottom line of Russel's answer is "if the US government is no longer in charge, who cares?".
And now I also get censorship in my post and a threat to be banned from the thread (from one of the people I am arguing with)
Not exactly mature behavior.
 
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  • #251
russ_watters said:
...planes and cars still crash, buildings burn and collapse and people die from inhaling the pollutants of other sources of energy.
And enormous coal-ash slurry dumps collapse releasing 4.2 million m^3 of silica and heavy metals into the surrounding environment and rivers in Kingston, TN, the largest in US history. Yet no mass marches occurred; nobody but @Astronuc even mentioned the spill on PF, and Jane Fonda did not make a "you're lucky to be alive" movie about mountains of sludge.
 
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  • #252
SredniVashtar said:
Still the same logical fallacy: since there are other poisons, this poison is not poisonous.
No, the assertions made above are that there are many possible toxins, and that the toxicity comes from the dose. The fallacy here is yours, textbook special pleading, e.g. treat my complaint in isolation without justification.

..I am talking about the 3% long-lived part that according to Krane and the Wolrd Nuclear Association requires long term storage (stated as a fact, not a myth).
The WNA states " ... requires isolation from the environment for many thousands of years". Some radioactive isotopes in high concentration, and drums of cadmium for instance, should be not be dumped in the food or fresh water supply, not ever for the drum of cadmium, and not for thousands of years for some isotopes.
 
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  • #253
SredniVashtar said:
I am talking about the 3% long-lived part that according to Krane and the Wolrd Nuclear Association requires long term storage (stated as a fact, not a myth).

So,

just why does it matter that it's dangerous for a long time?
 
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  • #254
SredniVashtar said:
Still the same logical fallacy: since there are other poisons, this poison is not poisonous.
As far as I can see, you keep arguing "since it stops being poisonous after a while, it must be particularly dangerous before".

Sure, if we had a magic wand to make nuclear waste disappear, we would do that. But we don't have the question "do we want nuclear waste or not". We have the question "do we want to operate nuclear power plants or not?". And we have to consider the benefits of nuclear power, and compare the harm of it to the harm of other electricity sources. Comparing nuclear waste to the waste of coal power plants or photovoltaics production, for example, is important. Considering nuclear waste without considering anything else is one-sided and cannot lead to educated decisions.
 
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  • #255
SredniVashtar said:
And the bottom line of Russel's answer is "if the US government is no longer in charge, who cares?".
A point to which you clearly have no response, since you have repeatedly declined to respond to it.
And now I also get censorship in my post...
I thought I was doing you a favor by editing-out a part of a reference to a personal communication. I did not remove any of the content as part of the discussion.
 
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  • #256
mfb said:
Nuclear waste mainly consists of nuclides with shorter half-life than uranium. It reaches the activity level (per mass) of uranium within 1000-10000 years, afterwards it has a lower activity (see the plot above).

The activity of uranium ore is not particularly benign. You wouldn't want to live in a house where floor is made from it, that's for sure.

Uranium radioactivity is mostly alpha and thus easily shielded. If you isolate it very well (including air-tight, for radon emissions), then it becomes almost as safe as granite. This shielding can be rather thin, ~1 mm.

But nuclear waste activity is qualitatively different from uranuim. It has a substantial gamma component, both direct from e.g. Cs-137 and also secondary gammas from beta electrons. Apart from well-known 30-year half life culprits, there are 200k year half life Tc-99 whose betas are 300 keV, and Sn-126 is both beta-active and has a strong gamma-active daughter, Sb-126. You can't wait those out in 1000 years, and shielding from gammas needs to be, as a minimum, some 5 centimeters if it's steel, tens of centimeters if it's concrete.
 
  • #257
mheslep said:
The radioisotopes with long half-lives are mostly alpha emitters that dose by ingestion, with no penetrating power. After 500-1000 years the radioactivity of a ton of spent fuel is on the order of that from a ton of Uranium ore dug from the ground.

Let's look at the concrete example of real-world nuclear waste. This is the state of the art in nuclear waste storage, the French vitrification technology and its final product, "Universal Canister-Vitrified", or UC-V (not mentioned in the table that it has 5 mm thick steel walls):

UC.png


(UC-C is a similar canister for compacted metal parts of spent fuel assemblies, not relevant for my purposes)

This is roughly what one ton of spent fuel looks like after reprocessing.
Check out the last item in the table. 14000 grays per hour of gamma. In "old units", it's some 1.4 *million* R/h. Please, never, ever even think about coming anywhere close enough to touching that thing.

Let's see... if it's mostly from Cs-137 and Sr-90, then every 30 years it is halved, every 300 years it is reduced by ~1000 times. So, in 600 years this canister would emit 14 mGy/h ~= 14 mSv/h. in 900 years, 14 uSv/h ~= 122 mSv/year. World average natural background is 3 mSv/year.

After about ~1000 years, other isotopes (e.g. Tc-99) start being important. So this canister won't become significantly more safe after that time.
 
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  • #258
nikkkom said:
The activity of uranium ore is not particularly benign. You wouldn't want to live in a house where floor is made from it, that's for sure.
I don't make my house floor out of uranium ore, and I don't make it out of nuclear waste either. Not the surface, and not the material 5 cm below the surface either.
nikkkom said:
Please, never, ever even think about coming anywhere close enough to touching that thing.
You cannot touch that thing. Because it is enclosed in more shielding.
Directly after reprocessing there are many shorter-living isotopes in it, so initially the activity will go down faster.
 
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  • #259
mfb said:
I don't make my house floor out of uranium ore, and I don't make it out of nuclear waste either. Not the surface, and not the material 5 cm below the surface either.

Exactly my point. Uranium ore is not a benchmark of safe material.

You cannot touch that thing. Because it is enclosed in more shielding.

It can not be enclosed during transport from vitrification facility to short term storage, and some years later, from short term storage to "E/EV/SE storage" which is designed for <500 Watt heat load.

Directly after reprocessing there are many shorter-living isotopes in it, so initially the activity will go down faster.

I'm not that sure about the "many" part. French do not reprocess the fuel right after they pulled it from the reactor. They let it cool for ~4 years. Thus, for example, 75% of Cs-134 is already gone by the time UC-V glass is poured. Which isotopes do you have in mind?
 
  • #260
nikkkom said:
Uranium ore is not a benchmark of safe material.
Safe in what context? Dumped into the food and water supply? No. In contact handling in mining operations, military munitions, enrichment facilities, or even that old uranium glass fixture sitting in your great aunts living room? No problem.
 
  • #261
mheslep said:
Safe in what context?

In the context you used it: "look, in only 900 years nuclear waste is as safe as uranium ore". Which is not a safety benchmark I am agreeing to.

Military munitions. First, they don't contain ore, they contain uranium metal. Which is ~8 times less radioactive, since all daughters are removed. Second, uranium metal in tank and GAU-8 30mm projectiles is not exposed, it's jacketed by other metals. (Not that complaints about "uranium in bullets is bad for your health" strike me as making much sense. If you are being fired upon by GAU-8, radiation from uranium is the least of your concerns...)

Enrichment facilities. They don't contain ore either, and they don't let people to come in touch with UF6 (it is unstable to water and forms corrosive products).

Uranium glass, again, does not contain ore, and U content is about 2%. Even after 900 years, vitrified waste is many orders of magnitude more radioactive (mainly due to gammas not shielded).
 
  • #262
nikkkom said:
In the context you used it: "look, in only 900 years nuclear waste is as safe as uranium ore". Which is not a safety benchmark I am agreeing to.
What @mheslep was asking (and now I am), is what is the benchmark you would agree to?

Surely you are not suggesting, as you seemed to before, that it should be safe enough to build household flooring out of it?

And surely you must see the logic in the "safer than when we dug it out of the ground" benchmark don't you? At that point we could literally put it back where we found it and the location we found it would be no worse off for having it back.
 
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  • #263
nikkkom said:
They let it cool for ~4 years. Thus, for example, 75% of Cs-134 is already gone by the time UC-V glass is poure
At creation, CS 134 (1300 Ci/gm) is more than 100x hotter than Cs 137 per gram. After 2 half lives, the original mass of Cs-134 and decay products is still ~3X hotter than Cs 137, and 134 is also a strong gamma emitter. Twenty years, and the 134 is essentially gone.
 
  • #264
nikkkom said:
Exactly my point. Uranium ore is not a benchmark of safe material.
It is. Uranium ore has been underground for billions of years. No one seems to be scared by that. Why should people be scared of nuclear material with the same activity, stored at locations that are better protected than the uranium mines?
nikkkom said:
It can not be enclosed during transport from vitrification facility to short term storage, and some years later, from short term storage to "E/EV/SE storage" which is designed for <500 Watt heat load.
Castor containers can handle tens of kW of heat. It can be contained, transported and stored easily.
nikkkom said:
Thus, for example, 75% of Cs-134 is already gone by the time UC-V glass is poured.
That is still 25% left that will decay within a few more years, and dominate the activity for a while. Typically the overall activity at a given time is dominated by just 1-2 isotopes, starting from short-living ones and transiting to longer-living ones once the short-living isotopes are gone. That leads to the characteristic wobbly shape of the overall activity in double-logarithmic plots.
 
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  • #265
russ_watters said:
> Thus, for example, 75% of Cs-134 is already gone by the time UC-V glass is poured.

That is still 25% left that will decay within a few more years, and dominate the activity for a while. Typically the overall activity at a given time is dominated by just 1-2 isotopes, starting from short-living ones and transiting to longer-living ones once the short-living isotopes are gone. That leads to the characteristic wobbly shape of the overall activity in double-logarithmic plots.

What isotopes, in your opinion, dominate initial radioactivity from UC-V canister?
 
  • #266
russ_watters said:
And surely you must see the logic in the "safer than when we dug it out of the ground" benchmark don't you?

Is it indeed safer? Compare uranium ore's gammas with French vitrified waste.

And secondly, why does US not do even what French are doing, which is at least converting spent fuel to this insoluble, chemically stable glass form? Hanford Vit Plant is what, costs $16B to date, not finished yet, and also even when completed, it can't reprocess fuel, it can only vitrify existing Hanford waste. I'm not feeling optimistic when I see this approach to nuclear waste treatment. "Safe vitrified glass 900 years later" is not what's happening in US, it's handwavium.
 
  • #267
nikkkom said:
why does US not do even what French are doing,
Politics driven by Plutonium separation in reprocessing.
 
  • #268
nikkkom said:
Is it indeed safer? Compare uranium ore's gammas with French vitrified waste.
You need to answer the question you were asked. This response makes it look like you don't have an answer/no level of safety would satisfy you. Is that the case?
 
  • #269
nikkkom said:
Is it indeed safer? Compare uranium ore's gammas with French vitrified waste.
Gamma radation doesn't penetrate hundreds of meters of rock. And vitrified nuclear waste is less likely to leak than uranium ore that has not been vitrified.
 
  • #270
russ_watters said:
What @mheslep was asking (and now I am), is what is the benchmark you would agree to?

Vitrified waste stored for ~100 years for cooldown, then dropped down 8 km into boreholes in a subduction zone would be enough for me. No one has full working plans to do something like this. French are the closest.
 
  • #271
nikkkom said:
No one has full working plans to do something like this.
That is just a political problem. Mainly driven by large parts of the general population disliking everything that remotely sounds like radioactivity. And we are back at the topic: A better education would help.
 
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  • #272
mfb said:
That is just a political problem. Mainly driven by large parts of the general population disliking everything that remotely sounds like radioactivity. And we are back at the topic: A better education would help.

Vit Plant cost overruns and 21 years construction schedule are also general population's fault?
 
  • #273
nikkkom said:
Vitrified waste stored for ~100 years for cooldown, then dropped down 8 km into boreholes in a subduction zone would be enough for me. No one has full working plans to do something like this. French are the closest.
I don't understand; if it can be safely stored for 100 years above ground, why does it need to be buried after becoming less dangerous?
 
  • #274
nikkkom said:
Vit Plant cost overruns and 21 years construction schedule are also general population's fault?
Not the entire population; just the portion working hard to cause those delays and overruns.
 
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  • #275
russ_watters said:
I don't understand; if it can be safely stored for 100 years above ground, why does it need to be buried after becoming less dangerous?

It is not safe above ground. Initially, it's too hot (thermally) to be lowered in the boreholes: when insulated by rocks, it may overheat and somewhat lose integrity. Also, transporting 1 million R/h gamma activity canisters to the burial site is more difficult than 100k R/h canisters.
 
  • #276
nikkkom said:
It is not safe above ground.
What negative things do you expect to happen during those 100 years?
 
  • #277
russ_watters said:
What negative things do you expect to happen during those 100 years?

I expect that French authorities will guard and protect the storage site and nothing bad will happen. However, absolutely guaranteeing that they will not fail is not possible.
 
  • #278
nikkkom said:
I expect that French authorities will guard and protect the storage site and nothing bad will happen.
Isn't that the definition of "safe"?
However, absolutely guaranteeing that they will not fail is not possible.
Of course not. Does that matter?
 
  • #279
russ_watters said:
Isn't that the definition of "safe"?

No, it is not. Seriously radioactive objects are supposed to be safeguarded everywhere. But in practice, this does not always happen. A selection of events since 2010:

***
April 2010 - INES level 4 - A 35-year-old man was hospitalized in New Delhi after handling radioactive scrap metal. Investigation led to the discovery of an amount of scrap metal containing 60Co in the New Delhi industrial district of Mayapuri. The 35-year-old man later died from his injuries, while six others remained hospitalized.

July 2010 - During a routine inspection at the Port of Genoa, on Italy's northwest coast, a cargo container from Saudi Arabia containing nearly 23 000 kg of scrap copper was detected to be emitting gamma radiation at a rate of around 500 mSv/h. After spending over a year in quarantine on Port grounds, Italian officials dissected the container using robots and discovered a rod of 60Co 23 cm long and 0.8 cm in diameter intermingled with the scrap.

December 2013 - A truck transporting a 111 TBq 60Co teletherapy source from a Tijuana hospital to a waste storage facility was hijacked near Mexico City.
***

Now, every of these sources pales in comparison to even a single UC-V, and French have many thousands of them! The chances of an upheaval in France akin to Syrian Civil War don't look likely at the moment, but in 100 years, who knows. I prefer UC-Vs to go deep under ground, so that any possible ransacking mobs couldn't possibly reach them.
 
  • #280
nikkkom said:
No, it is not. Seriously radioactive objects are supposed to be safeguarded everywhere.
What does that mean? You're just re-using the word you just said doesn't apply but described almost word-for-word the definition!
But in practice, this does not always happen. A selection of events since 2010:

***
April 2010 - INES level 4 - A 35-year-old man was hospitalized in New Delhi after handling radioactive scrap metal...
But we're not talking about radioactive scrap metal improperly left in a dump somewhere, we're talking about a French storage facility that even you have acknowledge you expect will not be compromised. No one is suggesting the stuff be discarded in a landfill! So this example is irrelevant, isn't it?

Earlier you suggested it would be unsafe to be used as flooring: but you don't *actually* think someone is going to break into that French storage facility, steal the radioactive material and sell in on the black market as a high density flooring product, do you?

So I'll ask again: If the French facility poses no significant risk over 100 years, then it is "safe", right? And if your answer is still no, then tell me what the expected harm is.
 
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