Wouldn't that depend on how far inland the mine is? Certainly, mining operations tend to pollute groundwater, but I wouldn't expect that a mine that's more than a few miles inland would significantly pollute the ocean via runoff.
True that it must be relatively close. It's about a 150 mile downstream impact. They also use fossil fuels in the extraction and processing, so it would still impact those islands anyways. It's still a step in the right direction but I can't wait to see economical super capacitors or alternative batteries (love those kinetic/gravity ones for grid storage).
