Cleanup of Leviathan Mine is going to be one huge project.
Environmental Protection Agency scientists have already begun studying ways to clean up the sulfur mine site, but the project manager says he may not have a strategy, let alone a completion date, for years.
"This is going to be a long-term project," said Kevin Mayer, the project manager. "It's not going to be fixed this summer. It's not going to be fixed next summer. We don't know how polluted the water is coming out of that mine. We don't even know how much contamination is coming out of that mine."
Mayer said in December that the mine site, located southwest of Gardnerville in Alpine County, Calif., will probably be added to the national Superfund list later this year. Superfund status would provide money and resources for cleanup, but also mark the 250-acre site as one of the most polluted in the country. The mine operated intermittently from 1863 to 1962, producing copper sulfate and sulfur.
Mayer said the Leviathan project is unique because the mine is leaching pollutants into watersheds that run into Nevada and cross federal, state and Washoe Tribal lands. Two creeks affected by contamination from Leviathan drain into the east fork of the Carson River, an important Carson Valley water source.
While scientists don't think the tainted water directly threatens the river or Carson Valley, Mayer said they plan to study upstream sediment so they can gauge the full impact.
Mayer said local concerns will be considered as cleanup methods are studied. While the Leviathan Mine pollution warrants federal attention, he noted the project lacks the magnitude of Superfund sites in heavily populated areas, where contamination might threaten the water supplies of hundreds of thousands of people.
"We don't have that here," said Mayer. "We've got a long-term, complex problem with multiple jurisdictions, a real serious ecological impact. Hopefully, we don't have quite the same direct human health impact. But the Washoe Tribe would say 'you haven't studied it enough,' and they would be right. We don't know there's no human health impact."
Already, insects and animals have been studied to determine how much chromium, arsenic, nickel and other toxins they have absorbed from the mine runoff. That information will be a foundation in assessing damage and judging the effectiveness of cleanup methods.
Mayer said the EPA welcomes comments from river users because the agency needs to know how close people get to the river. Washoe Tribe members have explained that traditional basket weaving involves plants that grow along the waterway, and the basketmakers use their mouths, not just hands, a potential exposure factor EPA hadn't realized.
"Until we know how much pollution there is and how clean we need to get it, we're not willing to say that we've got the answer," said Mayer. "We want to know if somebody really uses the resource in a way that we haven't factored in."
Even the road leading to the mine may need to be cleaned. It was built on waste rock from the mine, and the trucks that now bring materials to the site stir up dust.
Mayer said the EPA will probably hold forums in the coming months to explain the data already collected and what it means to Valley residents.
"We want to be able to make a decision as soon as we can, because with every year that goes by, there's more millions of gallons of stuff coming down the creek," he said. "The sooner it's cleaner, the better."
Leviathan Mine background
Leviathan Mine originally produced copper sulfate for processing silver ore at Virginia City when it was developed in 1863. From 1872 to 1935, the mine was inactive. It was reopened for development of the sulfur body until 1941, when it was closed again. When the Anaconda Co. purchased the property in 1951, sulfur extraction by open-pit methods started, resulting in millions of cubic yards of mine waste.
The first indication of pollution problems occurred in 1952 with a fish kill in the Carson River and a tributary, Bryant Creek, that resulted when a holding pond was breached and discharged toxic water into Leviathan Creek, which drains into Bryant.
California water quality officials got involved in cleanup efforts in the 1970s. The state, which now owns the mine site, negotiated a settlement with Anaconda, now a subsidiary of ARCO, and efforts at cleanup have been under way since the early 1980s.
Source: Environmental Protection Agency