The Leviathan Mine Superfund site in 2019.
Lisa Gavon
A 22-year process to come up with a plan to clean up the Leviathan Mine Superfund site may see completion of a milestone in the next few months.
Officials involved in the effort updated people in a virtual meeting on Monday night.
Decades before the Environmental Protection Agency declared the mine a major clean-up, acidic drainage from the former open pit sulphur mine turned the waters of Leviathan and Bryant creeks orange as water filtered through the tailings on the site.
One of the key issues to treating water coming off the site is that agencies only have access to it for half the year.
That challenge will be part of the final remediation plan which could be released for public review later this fall.
Since 2000, around 400 million gallons of water have been treated from the site to remove heavy metals leached from the tailings, said Environmental Protection Agency Remedial Project Manager Freyja Knapp.
Geologist Mark Lombardi, who is consulting with Atlantic Richfield on the clean-up, said getting the clean-up going year around will help speed its completion.
One of the issues is that the site, located southwest of Douglas County is at 7,000 feet and typically receives nearly 2 feet of winter precipitation, which causes increases in drainage that overwhelm the treatment ponds.
Those ponds will remain at the site, Lombardi said to handle the large spikes in flow from the site.
Lahontan Water Board Water Resource Control Engineer Hanna Bartholomew said the open pit mine in the 1950s and 1960s left piles of tailings.
“They took the whole top of the mountain off, removing 22 million tons of material,” she said.
The 200-foot tailings pile was left in the Leviathan Creek drainage that first came to light when Bryant Creek into the Carson River turned orange during major runoff events.
The water board conducted some work on the site around 1984, including a dam that created ponds to hold the drainage in place.
Bartholomew said the drainage from the mine includes sulphuric acid which is toxic to fish and damages habitat downstream.
One of the efforts over the next few years will be for work to make its way downstream to areas along Bryant and Leviathan creeks.
In 2013, the Park family filed a $128 million federal lawsuit over contamination of their 1,700-acre River Ranch located downstream from the mine.
In their lawsuit the Parks said the property was no longer fit for cattle to graze because heavy metals that ended up in the soil were taken up by grass.
For more information on the Leviathan Mine site, visit https://cumulis.epa.gov/supercpad/cursites/csitinfo.cfm?id=0901943
