They probably couldn't feasibly pre-clear this amount of land even if they wanted to. There are almost certainly resources (e.g. human remains and cultural site

They probably couldn't feasibly pre-clear this amount of land even if they wanted to. There are almost certainly resources (e.g. human remains and cultural sites) somewhere in that area that not only does the BLM not have authority over, but for which the existing legislation is basically Congress saying "Not within in our authority".