What are the obstacles in building a railway line on someones...

What are the obstacles in building a railway line on someones tenement? I would be pretty certain that RIO and BHP would resist any move by FMG to build rail to their big deposit, so perhaps the tenements around Iron valley are in play (ie the one Phil's creek in on). I will need to revisit the tenement holdings of IOH but I am sure they have some more slices of land around the place.
Having said that RIO may be right in the mix buying up more satellites, or the Indians, or Chinese....?

Central satellites can mean a lot of things, and be important for a number of reasons - so perhaps this will be a big deal after all.

I guess we will all find out soon enough.