A look at hidden dangers after at least 47,000 abandoned mines recorded in California

California officials have identified at least 47,000 abandoned mine sites statewide, but many more may remain undocumented, creating ongoing risks for residents, visitors and emergency responders. 7 On Your Side Investigates' Dan Noyes has the story. https://abc7news.com/19915082/ #mines #abandonedmines #california #7onyourside #investigation #abc7news