300 miles of bad road

No, literally 300 miles of bad road that can give you cancer. [Link]

In Dunn County, North Dakota, the roads can kill you. In fact, anything you do to disturb rocks in the area, like driving or even sweeping, can kick up naturally-occurring particles that lodge in your body and give you a rare kind of lung cancer up to 30 years later. Dunn County, you see, is home to a lot of rocks containing erionite, an asbestos-like substance that's highly toxic. Unfortunately, nobody knew that until very recently. And so at least 300 miles of roads in North Dakota are paved with the stuff.

What do you do when you discover that you've built your county's infrastructure out of poison rocks?