Slag dumping should pollute

I think that while it is fine dumping rock or even dirt into the ocean, slag is quite "dirty" and there should be some pollution that comes from dumping it into the ocean. Just to make it kinda like "waste-lite", whereas it doesn't pollute it you just drop it on a landfill, but if you try to use it for land reclamation it will pollute a fair amount (albeit way less than waste of course). Just a fun feature, an optional setting enabled on admiral difficulty or perhaps just as a strictly optional setting for custom difficulty games.