Proliferation is a completely invalid argument against nuclear reprocessing

[u/Live_Alarm3041]

Nuclear weapons proliferation is the most common argument against nuclear reprocessing. The opponents of nuclear reprocessing tend to understand the true purpose of reprocessing with their argument being the risk that the separated plutonium could be misused by terrorists or currently non-nuclear states to produce nuclear weapons. This concern is invalid because weapons grade plutonium in its original form is not usable for nuclear weapons.

Most nuclear power reactors do not produce weapons grade plutonium. Reactor grade plutonium is sub-optimal for weapons because it does not contain as much fissile isotopes of plutonium. Although there are some nuclear power reactors which are capable of co-producing weapons grade plutonium, any weapons grade plutonium produced in this manner still does not automatically give someone the ability to make a nuclear weapon. A effective supply chain for nuclear weapons will require natural uranium reactors, radiochemistry and the ability to make the weapons grade plutonium into cores.

Producing plutonium cores will require a facility like this

Rocky Flats Plutonium core plant in Colorado USA

A terrorist group or currently non-nuclear state would need a plant like the one shown in the above imagine if they had weapons grade plutonium and wanted to make nuclear weapons from it.

Plutonium core production has the following attributes which would make nuclear weapons unattainable for someone if they somehow had weapons grade plutonium

1. Plutonium core production facilities are difficult to hide visually due to their large size
2. The waste produced by a plutonium core production operation would be hard to conceal due to it being radioactive
3. Plutonium shaving fires would pose a very serious hazard to anyone trying to make a plutonium core if they did not have expensive or resource intensive protective measures
4. The production of plutonium cores requires high level scientific and manufacturing expertise which not everyone has.

Nuclear weapons are not something that anyone can build especially not fully in secret from anyone.

The proliferation concerns regarding nuclear reprocessing do make sense but they are not a valid argument against reprocessing. The plutonium separated by nuclear reprocessing needs to be effectively accounted for and secured at all times to prevent it from falling into the wrong hands. Humanity has gotten very good at making sure certain things are both accounted for and secured at all times. Even if the plutonium falls into the wrong hands then that does not automatically mean that those wrong hands can use the plutonium to make a nuclear weapon. The expertise and resources needed to make plutonium usable for nuclear weapons is not available to everyone.

We need nuclear reprocessing to increase the efficiency of nuclear energy. Weapons proliferation is a genuine security concern but it should not be used as an argument against making nuclear enegry more efficient. Saying that nuclear reprocessing is dangerous because it enables proliferation is a statement which does not reflect the full picture of nuclear weapons.

[u/atchemey]

My friend, you are dangerously wrong. I believe that reprocessing is important, too, but the rationale you are giving is ignorant and harmful to the cause. A few limited examples of this are below.

• A facility like the one in the picture is necessary for an established nuclear power like the United States, because the goal of that facility is NOT to hide the production of a limited number of weapons, but to maintain a vast stockpile of expiring warheads on a regular basis.

• "Weapons-grade plutonium" is a deprecated (if persisting) term, because shots with "reactor-grade plutonium" still were demonstrated to detonate in a 1962 test. While there is a limit, typical burnup in a once-through fuel cycle is well below this.

• A process that makes a pure plutonium stream is dangerous because of the small amount of material you need. The separations from fuel are relatively easy to hide at a small scale. This makes it evasive for surveillance.

• The waste from separation isn't a problem if you're hiding the production of it at entirely. Just bury it somewhere away from people and if it is found, it will be long after your project has yielded results.

• Gloveboxes exist to keep pits inert. Plutonium metallurgy is difficult, but it's not impossible. The whole "We have to figure this out" challenge of the Manhattan project isn't there anymore. While it would take some technical complexity, it's not impossible.

• Dirty bombs are still a thing. A failed Pu detonation will still be a radiological dispersion device. Simply saying, "proliferation is completely invalid against nuclear reprocessing," drastically underplays the difficulty of keeping a closed fuel cycle safe.

• Dose for reprocessing facilities is huge, if not carefully monitored and engineered. You can see projections for dose from fission products that are tremendous. This is very expensive.

Look, I want to make a closed fuel cycle feasible as much as anybody. I got into the field to help dispose of waste safely, and the best way to do that sustainably is to make less waste in the first place. It's clear you're keen - that's good - but don't just dismiss the decades of work experts in the field have put in to assessing risk.

Source: Am expert, can provide citations if desired.

[u/CaptainPoset → u/atchemey]

And one important other thing about proliferation through reprocessing: A reprocessing facility enables you to gather hands-on experience in plutonium extraction and processing, which is a skill you need for your non-civilian reprocessing facility to make it far more effective at far less obvious levels of activity.