My yard got dug up to run a sewer line. They filled it in after and planted seed. I couldn't possibly tell you where it happened now.
If they'd left a big pile of rocks in the spot, I'd bet I could find that.
If they'd left a big pile of rocks in the spot, I'd bet I could find that.
Not doing anything might indeed be better for the environment alone in isolation, but has to be balanced with other considerations, like the benefits of a power cable carrying clean power from wind farms to replace coal.
It is also entirely possible to plant native, locally appropriate seeds in a reasonably natural fashion. I am obviously not proposing a layer of lawn sod.
I think that's a question for the ecologists.
My guess, though, would be that part of the concern is people visiting the site on an ongoing basis as a tourist location, which won't happen with a buried power line.