mining is perfectly sustainable provided the thing they're digging up is valued/prioritized high enough. thing about closed mines is they're never actually "picked clean", they're picked to the extent that labor & technology made it profitable at the time. in the USSR mining continued, and the miners got better working conditions & more vacation time. they also didn't have to worry about the price of bauxite falling a cent & having to close the mine.

but mining towns actually should have a sustained presence afterward because mine-holes leak and require remediation for decades, which is more manageable with some leftover infrastructure