Broadly agree that we should be shipping waste to robust ecosystems, but I differ on where that is. Generally speaking deserts are more fragile than high moisture ecosystems, though. Cryptobiotic crusts can take hundreds of years to form, and even a small disruption can destroy them until they reform.

More robust ecosystems reform readily, like hardwood and softwood secondary growth forests in the US, for example. They can quite happily grow back in a few decades on top of a clay capped landfill.

Tundra might be a good place. Far enough north almost nothing grows.

Or perhaps abandoned quarries or mines? Or already damaged sites.

On the other hand even giant landfills aren’t that big in the scheme of things. They’re pretty low on my list of environmental problems.