Would the company runs its own trains in an open-acces regime, it would have to pay itself.
Would the company pay a railfreight operator to run the trains, track access would be paid by that operator, which of course would make part of the money the company asks for from the mine.
Would the freight branch of a state company broken into separate organiations do it, it would be the same story but with internally paid track access charges.
In a fully integrated state (or private) railway, track access would feature in internal price calculations.

At any rate, I note the gain for railways would be the transport of the ore on the entire route, not just the new track; would be nice if cost/benefit analyses for new line construction would reflect that.

_{*Lunatic*, n.
One whose delusions are out of fashion.}