Mining has left a toxic legacy across the West as abandoned mines continuously spill heavy metals and acidic mine drainage into our rivers. This is damaging to wildlife and the communities that rely on those rivers for clean drinking water, recreation, and river-based economic sustainability.The Animas River spill in Colorado is just the latest example of this problem. A wall blew out, dumping more than 3 million gallons of toxic waste into the river. This immediately affected residents in Colorado and New Mexico, but it will also affect communities downstream on the Navajo Nation in Arizona, as well as Lake Powell and the Grand Canyon.Experts estimate there are more than 55,000 mines like this throughout the West. They are ticking time bombs; it is not a matter of if they will spill but when. We need to stop them before they do more damage.