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While we’re at it, lets clear the obstacles to refining the spent fuel, so it takes up less space. You know, like other nations do?

How does that work? In layman's terms, please. LOL

How does that work? In layman's terms, please. LOL

In the US, recycling of spent fuel rods is not allowed (unlike Europe or japan) due to perceived danger of nuclear proliferation. This is absurd. It results in much more nuke waste than we would have if we just recycled

When most U.S. nuclear plants were built, the industry—with federal government encouragement—planned to recycle used nuclear fuel. In 1979, President Carter, completing a process begun by President Ford, banned commercial used nuclear fuel reprocessing in order to address concerns raised about the possible proliferation of nuclear weapons. This decision mandated a once-through, single use fuel cycle. Although President Reagan lifted the reprocessing ban in 1981, non-proliferation concerns continue to guide U.S. policy. Reprocessing and recycling are also not currently cost-effective in the United States, although recycling is being done in other countries.

How does that work? In layman's terms, please. LOL

Uranium is mostly U-238, but a small fraction is U-235. When U-235 his hit by a neutron, it breaks apart (fissions) and releases heat and two more neutrons which can go on to cause more fissions in other U-235 atoms.

U-238, on the other hand, usually absorbs the neutron to become U-239, which then takes a few days to decay into plutonium-239.

When there's too much U-238 and not enough U-235, the neutrons are nearly all absorbed by the U-238, and the chain reaction can't be sustained.

"Enriched" uranium means that the ratio of U-235 has been increased. With this increase it's possible to sustain a steady chain reaction, where enough new neutrons are released to keep the fissions going without being absorbed too soon.

The conversion of U-238 into Pu-239 essentially creates more fuel for the reactor, because Pu-239 can be fissioned when hit by a neutron. In a commercial reactor, up to a third of the heat comes from fission of the Pu-239 created when U-238 absorbs a neutron, and about half of what's created is used up in this way.

When enough of the U-235 and Pu-239 is used up, the rate of fission drops significantly. The fuel assembly is then removed from the reactor core and stored in a cooling pool. It is still highly radioactive because the "fission products," the leftover fragments of the fissioned Pu-239 and U-235, are very unstable and emit large amounts of radiation as they decay into stable forms.

Once the assembly cools down and the fission products have mostly decayed, the fuel can be taken out and chemically separated. The fission products are removed, and the uranium and plutonium which still make up the vast majority (about 97%) of the mass of the fuel can be pulled out.

This separated U can be re-enriched, and the fissile Pu can be mixed in with U-238, to create new fuel that can be used again in a reactor.

What's leftover after the U and Pu are pulled out makes up a fraction of the original fuel (~3%), and is only dangerously radioactive for hundreds of years, rather than millions of years. "A year's waste from a 1000 MWe reactor is contained in ... about 12 canisters 1.3 metres high and 0.4 metres in diameter."

If you think of a nuclear reactor as a campfire, America's once-through fuel cycle is like throwing a big log on the fire, and then pulling it out and throwing it away when the bark gets charred.

I think Carter's notion was that the risks and costs of reprocessing outweighed the costs of spent fuel storage and buying fresh uranium, but I expect that the calculus of spent fuel storage has changed over the years - Yucca Mountain was supposed to be online years and years ago.