Redford posted a blog entry Thursday on the Huffington Post website that says he's not against mining but is against "putting mega-mines where they don't belong." He also is speaking out in a New York Times advertisement paid for by the Natural Resources Defense Council asking mining companies Rio Tinto and Anglo American to leave Bristol Bay alone.

Redford describes Pebble as a disaster-in-the making. But the mining companies maintain they can develop the mine responsibly and without harming fish.