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Oklo, the Earth's Two-billion-year-old only Known Natural Nuclear Reactor (2018)

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Re: Oklo, the Earth's Two-billion-year-old only Known Natural Nuclear Reactor (2018)

#71

Post by lukan »

Manuel_D wrote: post #68
lukan wrote: post #67

Earlier quoted context omitted.

The point was, you cannot ignore the risks of transportation, if you only have some safe spots to burry it. And what you linked is still under construction. We don't know yet, if it really works safe long term, or if there will be future costs.

Finland has two other disposal sites in operation since the 90s: https://en.m.wikipedia.org/wiki/Deep_geological_repository

Yes, but when we want to store something in the range of million years, it is a bit early to say that 30 years are sufficient as a ultimate proof that nothing leaks.

Now I believe it can be done safely, but only if monitored all the time with good care. But that is expensive and humans tend to skimp.

Re: Oklo, the Earth's Two-billion-year-old only Known Natural Nuclear Reactor (2018)

#72

Post by Manuel_D »

lukan wrote: post #71
Manuel_D wrote: post #68

Earlier quoted context omitted.

Finland has two other disposal sites in operation since the 90s: https://en.m.wikipedia.org/wiki/Deep_geological_repository

Yes, but when we want to store something in the range of million years, it is a bit early to say that 30 years are sufficient as a ultimate proof that nothing leaks. Now I believe it can be done safely, but only if monitored all the time with good care. But that is expensive and humans tend to skimp.

Again, when you bury uranium half a kilometer deep in an area with no aquifer, how will it ever result in contamination?

The only real scenarios are deliberate excavation, and a meteor impact directly on the waste repository. Neither of which are particularly likely scenarios.

Re: Oklo, the Earth's Two-billion-year-old only Known Natural Nuclear Reactor (2018)

#73

Post by AnthonyMouse »

AtlasBarfed wrote: post #55
Manuel_D wrote: post #53

Earlier quoted context omitted.

2) I asked about waste buried in the ground, not in transit. 3) if a waste barrel explodes, somehow, underground how does the waste make it's way through a mile of bedrock? 4) Again, how does a fire bring the wast up through a mile of bedrock? 5) This is just a vague statement. 6) So the concern is that future society will forget that this is a waste site, mine a mile deep and retrieve waste, and never figure out tha…

I look forward to your revolutionary nuclear waste teleportation device.

The primary transportation risk is that spent fuel contains cesium metal, which is reactive with air and water, so if you expose it to air you get a fire.

It seems like a pretty obvious solution to this would be to purposely do the reaction under controlled conditions before transporting it, so then you're transporting stable cesium compounds instead of elemental cesium metal.

Re: Oklo, the Earth's Two-billion-year-old only Known Natural Nuclear Reactor (2018)

#74

Post by lukan »

Manuel_D wrote: post #72
lukan wrote: post #71

Earlier quoted context omitted.

Yes, but when we want to store something in the range of million years, it is a bit early to say that 30 years are sufficient as a ultimate proof that nothing leaks. Now I believe it can be done safely, but only if monitored all the time with good care. But that is expensive and humans tend to skimp.

Again, when you bury uranium half a kilometer deep in an area with no aquifer, how will it ever result in contamination? The only real scenarios are deliberate excavation, and a meteor impact directly on the waste repository. Neither of which are particularly likely scenarios.

Because the ground is not static. And we are just starting to understand what is going on down there. So yes, there are sites that remained quite unchanged (like with the natural fission reactor), but personally I remain sceptical with such statements.

Re: Oklo, the Earth's Two-billion-year-old only Known Natural Nuclear Reactor (2018)

#75

Post by Manuel_D »

lukan wrote: post #74
Manuel_D wrote: post #72

Earlier quoted context omitted.

Again, when you bury uranium half a kilometer deep in an area with no aquifer, how will it ever result in contamination? The only real scenarios are deliberate excavation, and a meteor impact directly on the waste repository. Neither of which are particularly likely scenarios.

Because the ground is not static. And we are just starting to understand what is going on down there. So yes, there are sites that remained quite unchanged (like with the natural fission reactor), but personally I remain sceptical with such statements.

Half a kilometer isn't particularly deep. There are dozens of mines over 2 KM deep: https://en.wikipedia.org/wiki/List_of_deepest_mines

Are we supposed to hold off on developing the only geographically independent and non-intermittent form of clean energy because of some vague nebulous fear that waste buried half a kilometer deep in bedrock will come back up to the surface and harm people... somehow?

Re: Oklo, the Earth's Two-billion-year-old only Known Natural Nuclear Reactor (2018)

#76

Post by lukan »

Manuel_D wrote: post #75
lukan wrote: post #74

Earlier quoted context omitted.

Because the ground is not static. And we are just starting to understand what is going on down there. So yes, there are sites that remained quite unchanged (like with the natural fission reactor), but personally I remain sceptical with such statements.

Half a kilometer isn't particularly deep. There are dozens of mines over 2 KM deep: https://en.wikipedia.org/wiki/List_of_deepest_mines Are we supposed to hold off on developing the only geographically independent and non-intermittent form of clean energy because of some vague nebulous fear that waste buried half a kilometer deep in bedrock will come back up to the surface and harm people... somehow?

No, but maybe we should not pretend all is super safe and always will be, when we cannot know currently.

Or rather we do know that the initial promises of reactor safety were also quite overconfident. So people assume the same of permanent storage of the waste.

Re: Oklo, the Earth's Two-billion-year-old only Known Natural Nuclear Reactor (2018)

#77

Post by pfdietz »

AtlasBarfed wrote: post #55
Manuel_D wrote: post #53

Earlier quoted context omitted.

2) I asked about waste buried in the ground, not in transit. 3) if a waste barrel explodes, somehow, underground how does the waste make it's way through a mile of bedrock? 4) Again, how does a fire bring the wast up through a mile of bedrock? 5) This is just a vague statement. 6) So the concern is that future society will forget that this is a waste site, mine a mile deep and retrieve waste, and never figure out tha…

I look forward to your revolutionary nuclear waste teleportation device.

If nuclear waste disposal were what is holding back nuclear energy, it would be in great shape. It's not a primary blocking problem.

Re: Oklo, the Earth's Two-billion-year-old only Known Natural Nuclear Reactor (2018)

#78

Post by pfdietz »

AnthonyMouse wrote: post #73
AtlasBarfed wrote: post #55

Earlier quoted context omitted.

I look forward to your revolutionary nuclear waste teleportation device.

The primary transportation risk is that spent fuel contains cesium metal, which is reactive with air and water, so if you expose it to air you get a fire. It seems like a pretty obvious solution to this would be to purposely do the reaction under controlled conditions before transporting it, so then you're transporting stable cesium compounds instead of elemental cesium metal.

The cesium in spent fuel is not in the form of cesium metal. The cesium there is already oxidized to the +1 oxidation state, as it is in cesium salts.

Re: Oklo, the Earth's Two-billion-year-old only Known Natural Nuclear Reactor (2018)

#79

Post by bobmcnamara »

Manuel_D wrote: post #53
bobmcnamara wrote: post #45

Earlier quoted context omitted.

1) the assumption that because something can be done safely it will be done safely 2) transportation to the site: https://static.ewg.org/files/nuclearwaste/plumes/national.pd... 3) exploding waste barrels due to corner cutting in kitty litter selection exposing surface workers and contaminating the work area - only 1/2 mile down but this type of accident is depth independent https://www.latimes.com/nation/la-na-new-m…

2) I asked about waste buried in the ground, not in transit. 3) if a waste barrel explodes, somehow, underground how does the waste make it's way through a mile of bedrock? 4) Again, how does a fire bring the wast up through a mile of bedrock? 5) This is just a vague statement. 6) So the concern is that future society will forget that this is a waste site, mine a mile deep and retrieve waste, and never figure out tha…

2/3/4) Please see historical data above regarding three burial sites. Practically today, these sites are built by mining.

5) Industry term. Operationalizing any significant system will involve human beings, and with it their workplace culture. You can read about it here: https://mshasafetyservices.com/fostering-a-culture-of-safety.... Many mining hese were written in blood.

6) No, the concern is that people may be harmed. You see we've lost track of radioactive waste in the past. And humans are remarkably curious. Often we've figured it out before anyone was harmed. Sometimes sadly not. But the harm is the concern, not the lack of knowledge of harm.

Re: Oklo, the Earth's Two-billion-year-old only Known Natural Nuclear Reactor (2018)

#80

Post by bobmcnamara »

Manuel_D wrote: post #62
lostlogin wrote: post #61

Earlier quoted context omitted.

Regarding 3) and 4): Ground water contamination.

You can dig in bedrock that has no groundwater. Furthermore, naturally occurring uranium exists in groundwater and needs to be filtered out in places where levels exceed safe limits. So it's not like burying waste is creating a new problem: https://www.kqed.org/stateofhealth/120396/uranium-contaminat...

Heavy metal and radiological exposure is not a boolean safe/unsafe.
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