From The Durango Herald (Dale Rodebaugh):
“We wanted to bring people up to date on the quality of water in the Animas and why it’s getting worse,” Peter Butler said Friday. “But any decisions are quite a ways off.” Butler is a member of the Animas River Stakeholders Group and chairman of the Colorado Water Quality Control Commission. He lives in La Plata County.
When Sunnyside Mining Co. ended operations in Silverton in 1991, it negotiated a court decree to plug mine outlet tunnels, including the main access, the American Tunnel, with bulkheads. But the bulkheads raised the subterranean water level tremendously, increasing pressure that created drainage in nearby mines that had been mostly dry. Since 2004, when treatment of mine drainage ceased at the American Tunnel, discharge has increased to a total of 700 gallons a minute from other mines in the Gladstone area. The American Tunnel still discharges 100 gallons a minute.
More Animas River watershed coverage here.