That $1000/kg figure is reprocessing something like 10kg of material to get 1kg of enriched material.

Current costs to launch a kg to orbit are something like $2,000-$6,000.

If we're comparing it to you enriched amount, you'd have to launch 10kg, which means you'd have to hit $100/kg launch costs to break even. I'm not convinced that will ever be possible; that's on the order of a first class arline ticket for a 50kg person.

This also doesn't consider what you're getting for launching it into orbit. If the 100 year risk of a casket leaking is (say) x mrads into the environment, you're going to have to consider what the equivalent of vaporizing all of it into the atmosphere in the event of a failed launch is. the fallout (hah) from a failed launch of nuclear waste seems magnitudes more catastrophic than having the same stuff slowly leaking in the middle of a desert cave.

> Current costs to launch a kg to orbit are something like $2,000-$6,000.

This is false. Launch on Falcon 9 is under $1K/kg.

Moreover, current launch costs are just a milestone toward future launch costs, which promise to me much lower. Ultimately launch will be a few times the cost of propellant (just like air travel), so $10/kg is a reasonable expectation.

> vaporizing in the atmosphere

How does this happen? Launch explosion? That doesn't vaporize an armored container. Entry from near-orbital speed? Also survivable passively.

The result of an accident will be tracking down the armored canister(s), cleaning up any local impact fragments, and prepared the stuff for another launch.

The armored canister doesn't have to be sent beyond LEO, so it could be reused, and doesn't impose a mass penalty on that beyond-LEO transport system.