I don't foresee miniaturizing the nuclear thermal electric generators in the future. And, thus it will likely be easier to track the waste than tracking waste AA batteries.
However, I could see a distinct advantage for a small thermal electric generator plant in Antarctic, rather than relying on Diesel generators for those months when the sun doesn't shine. And, as we were discussing in another chain, perhaps low level thermal energy production will become part of the nuclear fuel waste stream.
It certainly doesn't hurt to look at technology for recovering rare earth elements from sea water, but it likely isn't anywhere near being economically viable at this time.
Mining sediments from the deep sea? I have thought that may be a method to recover material for the low lying islands that are struggling with land mass issues. I suppose eventually we will look for mineral deposits locked in deep sea ridges, and go after them with robotic technology. If pollution could be kept to a minimum would building underwater caves benefit sea life?
There is all this talk about the warming of the deep... but how much is the deep sea actually warming? Is there a threshold for methane release? The greatest risk to the deep sea would be overwhelming the ocean mixing by adding substantial amounts of low density water to the Arctic. Which means not allowing glacial lakes to get too big.