For what it's worth, I spent a summer pulling off manhole covers for a living. There's no machine required, just a bent rod with a handle, and they're easy eno

For what it's worth, I spent a summer pulling off manhole covers for a living. There's no machine required, just a bent rod with a handle, and they're easy enough to open. And for the record, yes, it is quite easy to drop the rectangular covers into the hole.