This isn't just being opposed by the natives. I live in North Dakota. Lots of people don't want this to happen because the pipeline runs across a river that connects to the Mississippi. Not to mention a few lakes and ponds. If it were to leak or become damaged in any way, it would destroy large parts of the environment. In case anyone's forgotten too, there is lots of farmland in the midwest, so if there was any leaks, what is fertile farmland would also be destroyed. The fishing industry along the rivers as well would be completely destroyed.