There are lots of abandoned mines in Colorado. You’ve probably seen some of them maybe as you drive along I-70. Leftover rocks fan out from the openings and those rocks are laced with harmful stuff that can leach out and kill plants and fish, or worst case scenario, poison drinking water. Our guest thinks he has an inexpensive solution. Morgan Williams has researched this stuff called Biochar. Ryan Warner asks him to tell us about a mine near Aspen where he’s testing this new approach.