[satellites]

Why are you assuming that rare earth metals deep below the surface of the earth would benefit the life ON the surface that has evolved to live in the absence of those metals?

Even if for some bizarre reason the metals were beneficial, what about when the mining operation is done and humans leave the area? It just goes back to the previous status quo.

It’s a disruption either way.

[__Joker]

Also even if it is beneficial to some or all organism, generally eco system are based on equilibrium. Disturbing that would have consequence which we generally don't understand and can't predict.

[idontwantthis]

Because life does depend on these deposits at the surface. That’s why this is a huge danger to globally ecology. They feed a unique ecosystem.

[satellites]

Yes, but in specific quantities, no? Manually depositing them on the surface after extraction would still disrupt the system’s balance.

[jfoster]

But a good or bad disruption? Are you arguing that the ecosystem is currently optimal? It seems unlikely. So there's interesting questions; what's an optimal ecosystem look like? How can it be achieved?

[satellites]

Industrialized humans have a historically abysmal track record of ham-fistedly “optimizing” ecosystems.

Any manual intervention into an ecosystem generally requires establishing an indefinite commitment to more manual maintenance.

Who determines what “optimal” means? Who implements the optimization? Who pays for it? What happens in a few decades when people lose political interest in the project? Which creatures do we optimize for? Why are we doing this at all? How have similar projects fared in the past?

I can tell you haven’t seriously studied ecology from the way you are approaching this question, so I’m not too worried. But consider questions like those as you ponder this scenario.