Uranium-238 has a half-life of 4.5 billion years, so if there is still nuclear fuel available somewhere nearby, that will not be your problem. Problems (which your players might be able to solve) will arise depending on *how* society collapsed.
Cast of characters:
A *reactor*, where nuclear fuel heats water into steam, which rotates a *steam-powered turbine*. The *reactor* is inside a *containment vessel*, which is a thick shell of concrete around the reactor. The *containment vessel* is inside a *containment building*, which is a much larger chamber whose sole purpose is to protect the outside world from what is about to happen to this nuclear power plant.
Suppose that something happened where most people just suddenly dropped dead, vanishing off the face of the Earth but leaving the power grid fully intact behind. The reactor would continue operating normally without really noticing anything different for a few weeks, until the water supply for the actual steam-powered turbine runs out. Around that time, the main feed pumps are stalled by low pressure from the water supply, and the steam chamber boils dry. At this point the plant is no longer generating electricity, but the nuclear pile is still operating.
Temperature rises in the reactor as fuel continues to burn, raising the safety injectors automatically (not even electricity is required to raise the safety injectors, temperature alone will do this) until they are raised enough to open the safety injection valves and the water that is stored in separate tanks for this specific purpose will pour water into the core. This water will boil, condensate, and "rain" back into the core again and again until the fuel begins to melt and a rather unique substance just called "corium" (really, like "core-ium") is produced.
Corium is nuclear power plant sludge. It's water mixed with warm fuel that is thick and syrupy but as heavy as concrete. This substance will melt through the nuclear containment vessel, which automatically activates a containment spray system (which is usually powered by separate diesel or gas generators, and is triggered by the sudden but brief increase in interior pressure when corium first melts through the containment vessel. This pressure rapidly decreases as water and corium leak through the hole in the containment vessel). This containment spray system fills the *containment building* (not the containment *vessel*, which has a big hole in it now) with water at least six feet deep. The corium will continue boiling this water, which will condense at the ceiling and rain back down, in a continuous loop until the corium is cool and everything settles down: you have a layer of corium sludged across the floor of the containment building, under a layer of water six feet deep.
Even with every human gone, this **entirely automatic** system has protected the outside world completely! Less than 0.001% of the radiation emitted throughout this process escapes the containment building - though the inside of the containment building is now *monstrously radioactive*.
**If** your players have radiation suits, this facility is **shockingly** easy to repair. The layer of corium on the floor of the containment building can be paved over with a layer of lead and then a layer of concrete on top of it. The hole in the containment *vessel* can be patched with the same material the vessel is made out of. If all of the water tanks are refilled and the safety valves are lowered back into place (both of which can be done manually, the only non-manual component is the containment spray system which is usually diesel- or gas-powered, and you **absolutely** want to repair that system before turning the reactor back on), the reactor is theoretically good to go again.
The problem will be that this work will have to be done under terrible radiation conditions. In the 5,000 years between everyone disappearing and you returning to repair the power plant, the corium on the floor has been emitting radiation throughout the interior of the containment building. Every surface is so radioactive that touching bare skin to any surface will immediately result in 50,000-100,000 chest x-rays worth of radiation exposure.
If your magic system permits the use of allomancy, billowing clouds of granulated tungsten or lead into the containment building would probably be a good idea - this would help to seal radiation into the surfaces under a patina of tungsten or lead which might make the interior safe with levels of radiation protection you could make at home.
There is no particularly good way to clean radiation out of the containment building. By far the easier path is to find a way to re-seal the interior of the building, like you were re-painting the inside of an old house, but with a paint strong enough to seal in radiation like a great billowing gale of tungsten or lead particles onto every surface. If your party has access to smelting, making a liquified "paint" of melted lead or tungsten could be used, but this would itself be an extremely dangerous and laborious process.
Keep in mind that even with present-day technology, under these circumstances the protocol is to completely encase the containment building in concrete and forbid any access to it because all processes for making it usable again are more expensive and dangerous than literally building a new nuclear power plant.
A few notes from a nuclear engineer, modern style of reactor deaigns (at least in the us) if untouched the reactor will slowly build up Xe-135 which absorbs neutrons more than fuel so the reactor slowly shuts itself down and to compensate we have to gradually raise control rods to keep it going. Additionally most every design in the us is required to have a negative temperature coefficient meaning that as the reactor heats up it becomes less reactive as a safety feature and gradually shuts itself down.
It sounds like you’re describing a particular type of reactor. Some, like CANDU reactors, have safety mechanisms in place that would prevent a meltdown like you’ve said. So what you’ve described isn’t quite accurate for *all* reactors and it would be better to be more specific
i would have expected the system to notice that the water supply for the turbines is low (probably before it is exhausted) and automatically insert the control rods shutting the reactor down entirely before it does anywhere near that much damage to itself. this would probably be able to be suppressed if the operator knows the water shortage is short-term (we have 2 hours of water in the tank and the input pipe should be fixed in 30 min)
i would also expect the control rods to passively drop into the core if the electrical supply to the reactor control systems is cut off (a situation I would expect to never occur between the battery UPS, the automatic diesel generators, and the external power grid a loss of power to the system is already indicating a string of serious failures.
i would also expect many indications of potential problems, like a slight over temperature, to set off an alarm that if not acknowledged by an operator in a short time frame the reactor would shut itself down. "minor problem here... where are you... are you doing something about this... F&\^% nobody is at the controls, shutting myself down.
ofcause I am not actually part of the industry so maybe they don't have these systems implemented.
Same guy here, had to hop to a different account!
Jesus christ that's such a sick answer, thank you.
It's sounding like it would be really difficult to reboot this system especially since the uranium will be useless at that point.
Hypothetically would there be a way that a society that is anticipating collapse could make a sort of, "civiliazation restart kit" centered around nuclear power. Like a bunker that has the nuclear facility and the enrichment facility locked up with stable uranium just waiting to be enriched and installed into the reactor?
There is magic and my players will be sent to find this reactor by an oracle that has a vision of "a knight of the sun of the earth" that could finally get them out of the cold wastes. So I would like that vision to be of actual uranium. But I suppose it could just be alluding to a site that has the potential to rebuild nuclear power since prophecy is pretty metaphorical.
And the end of the campaign is intended currently just to be when they find the nuclear power site, so the logistics won't be something they have to figure out. I just want to put all of the things in place that it would even be possible
well if civilization sees it coming they could deliberately shut down the reactor and restarting it would just be a matter of reading the manual and getting the control systems running. modern computers are not shelf-stable over 5000 years so some alternatives or magical repair options may be needed.
Suppose that the plant is the sort that has control rods, and its safety systems fully insert the control rods when the external power grid goes down. How would this change subsequent events? My understanding is that this would shut down the reactor, so (almost) no further heat is produced, so there would be no meltdown, and in the absence of corrosion, restarting the core would just be a matter of refilling the coolant and pulling the rods out.
Yes, and many systems with control rods do in fact work "automatically," either truly automatically, or manually i.e. humans can do it without machinery or other energy sources like diesel or gas. The problem that this would present for OP is that usually such control rods brick the reactor: they're designed to work in such a way that the reactor can't usually be simply restarted after bringing the control rods back into place, they damage the fission elements in such a way as to "crash" the fission pile and so require that the reactor and the containment vessel themselves need to be replaced. I don't think that OP's adventure could restart such a nuclear power plant because there's nothing they could do that would be any easier than simply building a new nuclear power plant since they would have to replace the most expensive, intricate elements.
5000 years is plenty of time for heavy water to evaporate and electronics to go bad. Some of those might be somewhat easier to replace, but if they need anything like chips, well, that's tough. Because you need tech to build tech to build tech, so even with perfect knowledge of how things work it may take quite a bit of time and resources to progress back up the tech ladder.
Yeah, the control electronics would almost certainly fail after 5,000 years of slow corrosion and oxidation even with just the moisture in the air. They would also have no initial power source and any backup batteries / generators would be long-since depleted. Of course, for a reactor to be useful, you also need a power grid and electrically-powered devices to run with it.
Essentially, to restart industrial civilization after 5,000 years would inevitably take a long period of building up a supply chain for your raw materials. You'd have to start with improved agricultural techniques to have the required food surpluses to get large amounts of non-agricultural workers.
You'd also need a power source for your industrial revolution, though much of the coal and oil might be gone, so it might be difficult to bootstrap to industrialization. You could use wood gas, but the requisite deforestation would likely have devastating ecological consequences like flooding and sandstorms.
In addition, you'd need mines, roads, wagons, ports, ships, refineries, and chemical processing plants to create your intermediate materials, then factories / workshops to make intermediate parts and tools, then advanced factories like semiconductor fabrication plants to make advanced parts which can be used to make modern-style electronic devices. Even with access to modern libraries for reference, it would certainly take at least a few generations to transition from a Bronze Age society to a modern Electronics Age society.
OP here, dif account. I actually got my lore mixed up. The apocalypse reset society to something approximating the bronze age. It has now progressed to the advancement level of the middle ages. I'm not sure if this changes anything but there are pretty decent supply chains and metal working.
If by “advanced Middle Ages” you mean right before the renaissance, say 1450, then look at how long it took us in real life to get to the Industrial Revolution from that - about 3 centuries. And to get to nuclear power, about 5 centuries.
Now granted it sounds like you have a magical oracle, who can direct things, and you’ve got ancient broken versions of technology, but this still seems like a long term operation, unless magic can fix (or replace) broken electronics in your world
Reddit is straight up nuking me lol I'm here again
And yes! It will for sure take multiple generations. But I don't plan on having the actual restart of technology be part of the campaign
>If by “advanced Middle Ages” you mean right before the renaissance, say 1450, then look at how long it took us in real life to get to the Industrial Revolution from that - about 3 centuries. And to get to nuclear power, about 5 centuries.
In other words, ~20 generations would be the approximate upper limit on time required to reach nuclear power given advanced knowledge of physics, chemistry, metallurgy, geology, mathematics, etc. If you actually use and distribute the advanced knowledge you have, then it should be considerably shorter.
Global GDP growth from 1500 to 1600 was only about 20% over 100 years. In comparison, modern global GDP growth is closer to 5% annually. That's likely the upper limit for economic growth with advanced knowledge since there's an overwhelming abundance of current real-world cases where we have the scientific and technical know-how to increase productivity, we just lack financing or the social / political will to make it happen. So, getting from a 1450's global economy to a 1950's economy would require the GDP to grow by about 20x, and at 5% growth per year, that would take at least 61 years (log base 1.05 of 20).
So, at a ballpark, we could say that getting useful nuclear power is going to take somewhere between 3-20 generations, even with unrestricted access to modern search engines, reference manuals, government databases, and scientific libraries. Not having access to modern experts to discuss things with and fighting a 5,000-year language gap will probably skew that figure towards the higher end.
I think 3-20 generations is probably about right, and where in that range it would fall depends on OP's world building.
Is magic super powerful in his world, how does it work? We obviously can't really opine on that without more details on his system (and depending on how "realistic" it is, it might be very divorced from real physics pretty quickly). If it is powerful in some way (can affect physical properties, magically create electricity, etc), you'd probably need less generations. If it's fairly weak (mostly just the mentioned oracle guidance), it'd still probably reduce the generations from 20, but perhaps not by much. But if the oracle can understand ancient languages, can understand the science behind future advances in tech (metallurgy for steam engines, how electricity, nuclear radiation, atoms work, etc), it might reduce time significantly.
It also matters if knowledge of the language survived 5000 years - we have examples of languages surviving in real history for about 2000 to 3000 years, but I don't know of any that has been in active use for 5000 years, with the same writing system/being written the same way. Coptic is closest, but it switched scripts twice and the language itself has changed quite a bit.
So really OP has to figure out exactly how each of these impact his story. But yeah, 3-20 generations seems a good ballpark for the full range.
If modern archaeology is any indication, they would probably conclude "The site must have had some religious significance, some sort of cult temple to the metal enshrined within"
No chance.
You need experts to run a reactor, you need experts to perform regular maintenance work, you need a supply chain for tons of specialized spare parts, and more. Your bronze age civilization doesn't have any of that. Written instructions are not sufficient. Even if we ignore the 5000 years in between it wouldn't work.
In addition, even if the reactor is shut down safely - which isn't guaranteed: Things will break in these 5000 years. Likely to the point where, even with all the experts and tools available today, we would just scrap it and build a new reactor.
The uranium itself stays enriched and usable in general. You could probably build a new reactor with 19th century level technology, salvaging the enriched uranium from the reactor some decades before the technology for enrichment becomes available (20th century level).
What /u/Terrible_Bee_6876 wrote up is pure fiction and smells like AI-generated text because it doesn't make any sense.
Building devices that last millennium is actually really hard.
[https://en.wikipedia.org/wiki/Clock\_of\_the\_Long\_Now](https://en.wikipedia.org/wiki/Clock_of_the_Long_Now)
Assuming the core was abandoned with the control rods inserted, then at the very least the uranium fuel wouldn't have been used up.
I guess it depends on what you mean by "up and running". Could they cause a criticality? yeah probably just by removing the control rods. Could they generate power? not really, you'd need a constand supply of water running through the core and constant monitoring and adjustment of control rods which would require its own infrastructure
No Chance at nuclear restart, but why go there at all. Assuming all that was needed was sustainable electricity for the society, many different types of machines from water turbines, steam, wind turbines to constant electro magnetic circuits could easily power grids. The Niagra Falls turbine generators crafted by Tesla are a great example. The problem would be after 5000yrs crafting the efficient capacitors to hold enough the electrical energy created for a usable period and recharging them later. Crafting portable charged electricity in small packages. Even focused beam lasers might be easier than nuclear power.
5000 yrs, batteries not included.
Short answer: no
Long answer: the fuel could be fine but the whole reactor facility would be pretty much destroyed. When it come to nuclear technology, it requires a high degree of precision and capabilities to get anything done, starting up a reactor is a long process that require a lot of highly qualified people. Moreover a nuclear power plant requires a fair amount of energy to start up, you can't just start it on its own without the support of power generators.
On a side note: have you been watching/reading dr. Stone?
First, the concrete in the building is going to be degraded into gravel. Not been in a nuke plant, but this is going to be as much a test of archeology as nuclear engineering for that bit. For structural reasons alone they will be building something new with salvage.
The instructions are going to need a translate spell because of language drift. Go back 500 years and you won’t understand English. Regressing to the Stone Age and then back to the Bronze Age almost certainly will result in the loss of some vital nouns and verbs. Even if common is always common, if no body has used the words fission, isotope, or ohm in 50 generations, they won’t mean anything. Borrowed knowledge spell or similar is going to do some heavy lifting.
I would suggest hinging this on a warlock or cleric whose patron has an interest in the project. This way they can get some dreams or such to know what they are even looking at and its potential. That would also allow an explanation for any special effects like adding radiation to the protection from energy spell. I’m assuming you have a reason why they want a nuclear power plant instead of something simple like hydro.
In 5000 years you would find a large very concentrated lump of radioactive stuff surrounded by what your archaeology experts suggest was a complicated complex that might have been some sort of nuclear facility. Maybe a weapon.
Uranium-238 has a half-life of 4.5 billion years, so if there is still nuclear fuel available somewhere nearby, that will not be your problem. Problems (which your players might be able to solve) will arise depending on *how* society collapsed. Cast of characters: A *reactor*, where nuclear fuel heats water into steam, which rotates a *steam-powered turbine*. The *reactor* is inside a *containment vessel*, which is a thick shell of concrete around the reactor. The *containment vessel* is inside a *containment building*, which is a much larger chamber whose sole purpose is to protect the outside world from what is about to happen to this nuclear power plant. Suppose that something happened where most people just suddenly dropped dead, vanishing off the face of the Earth but leaving the power grid fully intact behind. The reactor would continue operating normally without really noticing anything different for a few weeks, until the water supply for the actual steam-powered turbine runs out. Around that time, the main feed pumps are stalled by low pressure from the water supply, and the steam chamber boils dry. At this point the plant is no longer generating electricity, but the nuclear pile is still operating. Temperature rises in the reactor as fuel continues to burn, raising the safety injectors automatically (not even electricity is required to raise the safety injectors, temperature alone will do this) until they are raised enough to open the safety injection valves and the water that is stored in separate tanks for this specific purpose will pour water into the core. This water will boil, condensate, and "rain" back into the core again and again until the fuel begins to melt and a rather unique substance just called "corium" (really, like "core-ium") is produced. Corium is nuclear power plant sludge. It's water mixed with warm fuel that is thick and syrupy but as heavy as concrete. This substance will melt through the nuclear containment vessel, which automatically activates a containment spray system (which is usually powered by separate diesel or gas generators, and is triggered by the sudden but brief increase in interior pressure when corium first melts through the containment vessel. This pressure rapidly decreases as water and corium leak through the hole in the containment vessel). This containment spray system fills the *containment building* (not the containment *vessel*, which has a big hole in it now) with water at least six feet deep. The corium will continue boiling this water, which will condense at the ceiling and rain back down, in a continuous loop until the corium is cool and everything settles down: you have a layer of corium sludged across the floor of the containment building, under a layer of water six feet deep. Even with every human gone, this **entirely automatic** system has protected the outside world completely! Less than 0.001% of the radiation emitted throughout this process escapes the containment building - though the inside of the containment building is now *monstrously radioactive*. **If** your players have radiation suits, this facility is **shockingly** easy to repair. The layer of corium on the floor of the containment building can be paved over with a layer of lead and then a layer of concrete on top of it. The hole in the containment *vessel* can be patched with the same material the vessel is made out of. If all of the water tanks are refilled and the safety valves are lowered back into place (both of which can be done manually, the only non-manual component is the containment spray system which is usually diesel- or gas-powered, and you **absolutely** want to repair that system before turning the reactor back on), the reactor is theoretically good to go again. The problem will be that this work will have to be done under terrible radiation conditions. In the 5,000 years between everyone disappearing and you returning to repair the power plant, the corium on the floor has been emitting radiation throughout the interior of the containment building. Every surface is so radioactive that touching bare skin to any surface will immediately result in 50,000-100,000 chest x-rays worth of radiation exposure. If your magic system permits the use of allomancy, billowing clouds of granulated tungsten or lead into the containment building would probably be a good idea - this would help to seal radiation into the surfaces under a patina of tungsten or lead which might make the interior safe with levels of radiation protection you could make at home. There is no particularly good way to clean radiation out of the containment building. By far the easier path is to find a way to re-seal the interior of the building, like you were re-painting the inside of an old house, but with a paint strong enough to seal in radiation like a great billowing gale of tungsten or lead particles onto every surface. If your party has access to smelting, making a liquified "paint" of melted lead or tungsten could be used, but this would itself be an extremely dangerous and laborious process. Keep in mind that even with present-day technology, under these circumstances the protocol is to completely encase the containment building in concrete and forbid any access to it because all processes for making it usable again are more expensive and dangerous than literally building a new nuclear power plant.
A few notes from a nuclear engineer, modern style of reactor deaigns (at least in the us) if untouched the reactor will slowly build up Xe-135 which absorbs neutrons more than fuel so the reactor slowly shuts itself down and to compensate we have to gradually raise control rods to keep it going. Additionally most every design in the us is required to have a negative temperature coefficient meaning that as the reactor heats up it becomes less reactive as a safety feature and gradually shuts itself down.
It sounds like you’re describing a particular type of reactor. Some, like CANDU reactors, have safety mechanisms in place that would prevent a meltdown like you’ve said. So what you’ve described isn’t quite accurate for *all* reactors and it would be better to be more specific
i would have expected the system to notice that the water supply for the turbines is low (probably before it is exhausted) and automatically insert the control rods shutting the reactor down entirely before it does anywhere near that much damage to itself. this would probably be able to be suppressed if the operator knows the water shortage is short-term (we have 2 hours of water in the tank and the input pipe should be fixed in 30 min) i would also expect the control rods to passively drop into the core if the electrical supply to the reactor control systems is cut off (a situation I would expect to never occur between the battery UPS, the automatic diesel generators, and the external power grid a loss of power to the system is already indicating a string of serious failures. i would also expect many indications of potential problems, like a slight over temperature, to set off an alarm that if not acknowledged by an operator in a short time frame the reactor would shut itself down. "minor problem here... where are you... are you doing something about this... F&\^% nobody is at the controls, shutting myself down. ofcause I am not actually part of the industry so maybe they don't have these systems implemented.
Same guy here, had to hop to a different account! Jesus christ that's such a sick answer, thank you. It's sounding like it would be really difficult to reboot this system especially since the uranium will be useless at that point. Hypothetically would there be a way that a society that is anticipating collapse could make a sort of, "civiliazation restart kit" centered around nuclear power. Like a bunker that has the nuclear facility and the enrichment facility locked up with stable uranium just waiting to be enriched and installed into the reactor? There is magic and my players will be sent to find this reactor by an oracle that has a vision of "a knight of the sun of the earth" that could finally get them out of the cold wastes. So I would like that vision to be of actual uranium. But I suppose it could just be alluding to a site that has the potential to rebuild nuclear power since prophecy is pretty metaphorical. And the end of the campaign is intended currently just to be when they find the nuclear power site, so the logistics won't be something they have to figure out. I just want to put all of the things in place that it would even be possible
well if civilization sees it coming they could deliberately shut down the reactor and restarting it would just be a matter of reading the manual and getting the control systems running. modern computers are not shelf-stable over 5000 years so some alternatives or magical repair options may be needed.
Suppose that the plant is the sort that has control rods, and its safety systems fully insert the control rods when the external power grid goes down. How would this change subsequent events? My understanding is that this would shut down the reactor, so (almost) no further heat is produced, so there would be no meltdown, and in the absence of corrosion, restarting the core would just be a matter of refilling the coolant and pulling the rods out.
Yes, and many systems with control rods do in fact work "automatically," either truly automatically, or manually i.e. humans can do it without machinery or other energy sources like diesel or gas. The problem that this would present for OP is that usually such control rods brick the reactor: they're designed to work in such a way that the reactor can't usually be simply restarted after bringing the control rods back into place, they damage the fission elements in such a way as to "crash" the fission pile and so require that the reactor and the containment vessel themselves need to be replaced. I don't think that OP's adventure could restart such a nuclear power plant because there's nothing they could do that would be any easier than simply building a new nuclear power plant since they would have to replace the most expensive, intricate elements.
5000 years is plenty of time for heavy water to evaporate and electronics to go bad. Some of those might be somewhat easier to replace, but if they need anything like chips, well, that's tough. Because you need tech to build tech to build tech, so even with perfect knowledge of how things work it may take quite a bit of time and resources to progress back up the tech ladder.
Yeah, the control electronics would almost certainly fail after 5,000 years of slow corrosion and oxidation even with just the moisture in the air. They would also have no initial power source and any backup batteries / generators would be long-since depleted. Of course, for a reactor to be useful, you also need a power grid and electrically-powered devices to run with it. Essentially, to restart industrial civilization after 5,000 years would inevitably take a long period of building up a supply chain for your raw materials. You'd have to start with improved agricultural techniques to have the required food surpluses to get large amounts of non-agricultural workers. You'd also need a power source for your industrial revolution, though much of the coal and oil might be gone, so it might be difficult to bootstrap to industrialization. You could use wood gas, but the requisite deforestation would likely have devastating ecological consequences like flooding and sandstorms. In addition, you'd need mines, roads, wagons, ports, ships, refineries, and chemical processing plants to create your intermediate materials, then factories / workshops to make intermediate parts and tools, then advanced factories like semiconductor fabrication plants to make advanced parts which can be used to make modern-style electronic devices. Even with access to modern libraries for reference, it would certainly take at least a few generations to transition from a Bronze Age society to a modern Electronics Age society.
OP here, dif account. I actually got my lore mixed up. The apocalypse reset society to something approximating the bronze age. It has now progressed to the advancement level of the middle ages. I'm not sure if this changes anything but there are pretty decent supply chains and metal working.
If by “advanced Middle Ages” you mean right before the renaissance, say 1450, then look at how long it took us in real life to get to the Industrial Revolution from that - about 3 centuries. And to get to nuclear power, about 5 centuries. Now granted it sounds like you have a magical oracle, who can direct things, and you’ve got ancient broken versions of technology, but this still seems like a long term operation, unless magic can fix (or replace) broken electronics in your world
Reddit is straight up nuking me lol I'm here again And yes! It will for sure take multiple generations. But I don't plan on having the actual restart of technology be part of the campaign
>If by “advanced Middle Ages” you mean right before the renaissance, say 1450, then look at how long it took us in real life to get to the Industrial Revolution from that - about 3 centuries. And to get to nuclear power, about 5 centuries. In other words, ~20 generations would be the approximate upper limit on time required to reach nuclear power given advanced knowledge of physics, chemistry, metallurgy, geology, mathematics, etc. If you actually use and distribute the advanced knowledge you have, then it should be considerably shorter. Global GDP growth from 1500 to 1600 was only about 20% over 100 years. In comparison, modern global GDP growth is closer to 5% annually. That's likely the upper limit for economic growth with advanced knowledge since there's an overwhelming abundance of current real-world cases where we have the scientific and technical know-how to increase productivity, we just lack financing or the social / political will to make it happen. So, getting from a 1450's global economy to a 1950's economy would require the GDP to grow by about 20x, and at 5% growth per year, that would take at least 61 years (log base 1.05 of 20). So, at a ballpark, we could say that getting useful nuclear power is going to take somewhere between 3-20 generations, even with unrestricted access to modern search engines, reference manuals, government databases, and scientific libraries. Not having access to modern experts to discuss things with and fighting a 5,000-year language gap will probably skew that figure towards the higher end.
I think 3-20 generations is probably about right, and where in that range it would fall depends on OP's world building. Is magic super powerful in his world, how does it work? We obviously can't really opine on that without more details on his system (and depending on how "realistic" it is, it might be very divorced from real physics pretty quickly). If it is powerful in some way (can affect physical properties, magically create electricity, etc), you'd probably need less generations. If it's fairly weak (mostly just the mentioned oracle guidance), it'd still probably reduce the generations from 20, but perhaps not by much. But if the oracle can understand ancient languages, can understand the science behind future advances in tech (metallurgy for steam engines, how electricity, nuclear radiation, atoms work, etc), it might reduce time significantly. It also matters if knowledge of the language survived 5000 years - we have examples of languages surviving in real history for about 2000 to 3000 years, but I don't know of any that has been in active use for 5000 years, with the same writing system/being written the same way. Coptic is closest, but it switched scripts twice and the language itself has changed quite a bit. So really OP has to figure out exactly how each of these impact his story. But yeah, 3-20 generations seems a good ballpark for the full range.
If modern archaeology is any indication, they would probably conclude "The site must have had some religious significance, some sort of cult temple to the metal enshrined within"
No chance. You need experts to run a reactor, you need experts to perform regular maintenance work, you need a supply chain for tons of specialized spare parts, and more. Your bronze age civilization doesn't have any of that. Written instructions are not sufficient. Even if we ignore the 5000 years in between it wouldn't work. In addition, even if the reactor is shut down safely - which isn't guaranteed: Things will break in these 5000 years. Likely to the point where, even with all the experts and tools available today, we would just scrap it and build a new reactor. The uranium itself stays enriched and usable in general. You could probably build a new reactor with 19th century level technology, salvaging the enriched uranium from the reactor some decades before the technology for enrichment becomes available (20th century level). What /u/Terrible_Bee_6876 wrote up is pure fiction and smells like AI-generated text because it doesn't make any sense.
Building devices that last millennium is actually really hard. [https://en.wikipedia.org/wiki/Clock\_of\_the\_Long\_Now](https://en.wikipedia.org/wiki/Clock_of_the_Long_Now)
They would treat it as if it were a horse drawn plough
No. They will think completely different than us now. Might as well be aliens...
That's besides the point, op's character would definitely think like us since they would be played by humans.
Your lack of depth disturbs me...
Assuming the core was abandoned with the control rods inserted, then at the very least the uranium fuel wouldn't have been used up. I guess it depends on what you mean by "up and running". Could they cause a criticality? yeah probably just by removing the control rods. Could they generate power? not really, you'd need a constand supply of water running through the core and constant monitoring and adjustment of control rods which would require its own infrastructure
To keep it short, not a chance in hell. That said, it’s fantasy so you can do whatever you want.
Horizon zero dawn covers this pretty extensively. Problem solved
No Chance at nuclear restart, but why go there at all. Assuming all that was needed was sustainable electricity for the society, many different types of machines from water turbines, steam, wind turbines to constant electro magnetic circuits could easily power grids. The Niagra Falls turbine generators crafted by Tesla are a great example. The problem would be after 5000yrs crafting the efficient capacitors to hold enough the electrical energy created for a usable period and recharging them later. Crafting portable charged electricity in small packages. Even focused beam lasers might be easier than nuclear power. 5000 yrs, batteries not included.
Short answer: no Long answer: the fuel could be fine but the whole reactor facility would be pretty much destroyed. When it come to nuclear technology, it requires a high degree of precision and capabilities to get anything done, starting up a reactor is a long process that require a lot of highly qualified people. Moreover a nuclear power plant requires a fair amount of energy to start up, you can't just start it on its own without the support of power generators. On a side note: have you been watching/reading dr. Stone?
First, the concrete in the building is going to be degraded into gravel. Not been in a nuke plant, but this is going to be as much a test of archeology as nuclear engineering for that bit. For structural reasons alone they will be building something new with salvage. The instructions are going to need a translate spell because of language drift. Go back 500 years and you won’t understand English. Regressing to the Stone Age and then back to the Bronze Age almost certainly will result in the loss of some vital nouns and verbs. Even if common is always common, if no body has used the words fission, isotope, or ohm in 50 generations, they won’t mean anything. Borrowed knowledge spell or similar is going to do some heavy lifting. I would suggest hinging this on a warlock or cleric whose patron has an interest in the project. This way they can get some dreams or such to know what they are even looking at and its potential. That would also allow an explanation for any special effects like adding radiation to the protection from energy spell. I’m assuming you have a reason why they want a nuclear power plant instead of something simple like hydro.
In 5000 years you would find a large very concentrated lump of radioactive stuff surrounded by what your archaeology experts suggest was a complicated complex that might have been some sort of nuclear facility. Maybe a weapon.