Federal and state officials are working desperately to keep thousands - maybe millions - of gallons of polluted water from flowing from the Leviathan Mine into tributaries of the East Fork of the Carson River this spring.
Chances of a complete success are slim. However, for every day officials are able to keep working at the Alpine County mine, they are likely stopping tens of thousands of gallons of acidic, toxic water from hitting Leviathan Creek, which runs into nearby Bryant Creek and eventually the river.
"It's certainly worth a try," said Kevin Mayer, Superfund project manager for the U.S. Environmental Protection Agency. "It's the right thing to do. There's no question about that. It just might not be enough."
Officials from EPA, which is proposing to list the mine on its Superfund national priorities list, and the Lahontan Regional Water Quality Control Board, which owns the site, hiked up to the 7,800-foot elevation mine on March 17 and found a problem they had not expected.
Five ponds have long captured the spring runoff of polluted water. Together, they hold about 16 million gallons of acid mine drainage - acidic water containing dissolved toxic metals such as iron, copper, aluminum, nickel and arsenic. Historically, there have been problems because only a few million gallons evaporate in a year. When six or more million gallons are created each spring, there has been a major overflow.
Lahontan last year installed a $1 million system for treating the contaminated water, creating 4.5 million gallons of extra capacity.
Officials this winter knew the ponds were nearly full, and that overflow was likely. However, when they hiked to the mine earlier this month they found that sheets of ice were present in many of the ponds, separating nearly clean water from acid mine drainage, which means that the clean water was taking up needed space in the evaporation ponds.
Mayer said officials believe that, with the late snows this winter, relatively clean water froze in the ponds before contaminated runoff started draining into them.
Because the toxic water was separated from cleaner water, last week EPA and Lahontan officials started pumping the better-quality water out of three of the ponds to try to create more capacity. Officials over the weekend were able to pump out about 50,000 gallons and hoped to do that much on Monday.
However, 36,000 gallons of acid drainage is flowing into the ponds each day, and that number may increase as more snow melts. And, as temperatures remain warm, the ice in the ponds may soon melt, mixing the clean water and acid mine drainage. That has already happened at one pond, and pumping has stopped.
Runoff is mostly diverted into the five evaporation ponds. However, overflow of the ponds isn't the only way contaminants are entering the creek. At least two seeps exist that are discharging polluted water into Leviathan Creek.