The most logical place to put a smelter is immediately on top of the deposit. Unfortunately, because of the soil conditions in the Ring of Fire, that's not going to be possible. As Chief Moonias has pointed out, it's like trying to build on a sponge.
That's one of the reasons Noront is focused on doing all of its development underground. That includes our tailings storage and the transportation of our concentrates. Placing it underground significantly limits its impact on the environment.