To my knowledge, all french highways and major railways are also already populated with fiber so you can just rent some point-to-point transit there from established operators without having to lay your own.
Good luck with this project keep us updated
I assume the former because the conversation was about USA in the first place. It is my understanding that US industry and law enforcement has exactly 0 respect for peace treaties with indigenous nations and their territorial sovereignty, especially when it comes to extracting natural resources.
However, it's good if local communities care for respecting other people's lands. If your fiber needs to cross private property or indigenous reservations, i'd recommend having an honest discussion with their residents. Maybe some would actually like to have good connection as a public service (as the Rhizomatica project has been building mobile phone and internet infrastructure for some communities in another part of the world) but would be hostile to private for-profits ignoring their needs.
I looked at some major carriers maps, and it looks like you are going to need to trench at least 25-30 miles of fiber along 502 and 84 to reach the Zayo fiber running along 25 south of Santa Fe.
THe Nuclear Security Administration is in the process of laying a second fiber path to the lab up there, and while you have zero chance of piggy backing on a DoE fiber line the planning documents might be helpful in figuring out what is viable and what isn't. https://www.energy.gov/sites/default/files/2020/04/f74/final...
(Feel free to email me if you need further help, it is in my profile)