Peter Butler's late October tour of abandoned hardrock mines began high on Red Mountain Pass near Silverton, Colo., off a highway so narrow that, in places, its shoulder crumbles off cliffs. Butler, a water wonk with springy silver curls, is the co-coordinator of the Animas River Stakeholders Group, a local watershed group, which has been cleaning up abandoned mines for 18 years. Standing on a buried mine waste pile, he pointed at a success story: Twelve years ago, an unlined ditch leaked water into the San Antonio Mine and reacted with pyrite -- fool's gold -- creating sulfuric acid. The acid dissolved naturally occurring metals, such as aluminum and zinc, dyeing the water that leaked out fantastic colors. "People looked at it and went, 'Wow, that's really pretty,' " Butler said. But it helped make the river below nearly lifeless for miles. So ARSG bought the water rights, filled in the ditch and diverted the water, keeping it from becoming contaminated.
Acid mine drainage is a major problem in the West. In Colorado, over half of impaired streams are contaminated by metals, many from draining mines. Groups like Butler's want to help with simple solutions like this one, which has significantly reduced downstream levels of zinc, copper and cadmium. But overall, their impact is limited because many draining mines need actual water treatment -- something that small environmental groups won't do because: (a) it can be really expensive; and (b) they could be sued if the water still doesn't meet federal standards.
Under the Clean Water Act, "Good Samaritans" who try to clean up a mine's drainage may become liable for any pollution that continues to flow from it. In the Animas River Basin, Butler's group has only worked on five of the most-polluted draining mines; they're afraid to touch the 28 others. Attempts to change the law have failed repeatedly. Last month, the Environmental Protection Agency issued a memo that attempts to clarify Good Samaritans' liability. But environmental groups are still unsure, or downright skeptical, that it will help.
"We've done the best we can with what's available to us," says Bruce Stover, who directs the inactive mine reclamation program for the Colorado Division of Reclamation Mining and Safety. "(But) the lion's share is still left to do."
One group that doesn't have to worry as much about getting sued, and has therefore made progress, is the Bureau of Land Management. The agency is already liable for what happens on its land, allowing it to be more experimental than Good Samaritans. Near Silverton Mountain ski area, Butler pointed out a white box on a forested hillside filled with charcoal-like materials that precipitate metals out of mine drainage. Another BLM experiment involves a limestone-coated channel that raises the pH of water draining from a mine.
Solutions like these, which improve water quality but remain imperfect, are too risky for small groups like Butler's. Instead, they perform legal workarounds -- trying to keep water from getting contaminated in the first place. They move mine waste out of the path of runoff, or keep water out of mines like the San Antonio. Still, the line between removing pollution from water, which is risky, and pre-empting pollution, which is not, is often blurry. Over apple pie, Butler and Steve Fearn, his group's co-coordinator, confessed that, at a different mine, they had added lime to acidic water to neutralize it.
"That could be considered treatment," Butler conceded.
"Oh," Fearn responded, "I could be sued," and they both laughed.