The public comment period ends Monday, June 4th for a proposal to expand the tailings facility at a Juneau area mine. The Hecla Greens Creek silver mine on Admiralty Island is one of Juneau’s biggest employers. Nearly six-hundred jobs are associated with the mine. But the facility also straddles a boundary for the Admiralty Island National Monument, one of the more-pristine areas in Southeast Alaska.
The Greens Creek mine is running out of space to stack tailings. The 65-acre tailings facility will be at capacity in two years. It’s earlier than expected because of increased- and prolonged-production, earlier dumping of waste rock, and various geo-technical factors that prevent the stacking of dry tailings too high.
“Once the capacity was exhausted, the mine would shut down,” said Greens Creek manager Scott Hartman.
He said his company needs to expand the facility to provide for another 30- to 50-years of mine life.
Tailings are what’s left after the valuable minerals are extracted. They’re hauled by truck from the mine and mill located within the Monument and stacked at a facility – actually right on the Monument boundary – near the old Hawk Inlet cannery and current ore terminal.
“Over half the existing facility is already in the monument. So while the Monument is a very special place, the entire island is for that matter.”
Hartman says it’s actually cheaper to reuse tailings, mix with cement to back-fill voids or previously mined areas. But it’s impossible to reuse all of it since that would block access to key areas underground.
“You have to leave areas open so you can access the next piece adjacent to it.”
The draft Environmental Impact Statement includes four alternatives. ‘B’ is a major expansion of the current facility south within the Monument. Two other alternatives — ‘C’ and ‘D’ — include expansion of the current tailings along with construction of a new facility north of the Monument on the road to the Young Bay commuter ferry dock. The ‘No Action Alternative’ would lead to the mine’s closure.
“We accept the fact that mine is going to continue and they’re going to need more capacity for disposal. That’s really not the question. The question is where should this occur.”
Bruce Baker of Friends of Admiralty Island says they prefer Alternative C that includes building an additional tailings facility outside the Monument and a fractional expansion to the current facility. The conservation and advocacy group recently chartered a catamaran trip to Hawk Inlet and to discuss the environmental and cultural significance of the area.
“It’s common to have acid drainage flowing off of upland storage piles no matter what precautions, mitigation is taken,” said Baker.
Guy Archibald of the Southeast Alaska Conservation Council says sulfate in the rock has the potential to generate that acid.
“The sulfuric acid dissolves out a lot of the other heavy metals and makes them mobile in the water,” said Archibald.
The Forest Service is working with the mine to minimize those heavy metal discharges. Chad VanOrmer is district ranger for the Admiralty Island National Monument.
“We’re really trying to design the tailings facility so all that water is contained and treated before being released back out,” said VanOrmer.
Juneau resident Joe Zuboff spent his childhood in Angoon, and – as a clan leader – often returns. He’s upset that few from his home village are working at the mine. He already considers the tailings facility as an eyesore when you fly over. He wonders about the potential impact to subsistence resources on land, and in the Inlet where fishing boats used to be tied up.
“There are halibut in here, said Zuboff. “But they’re not the large halibut that we normally used to get in here.”
Mine manager Scott Hartman says he would rather not build a new, additional tailings facility outside the Monument.
“It disturbs more ground. It disturbs more wetlands. It requires more construction of pipeline. It adds 6-miles to round-trip of heavy hauling.”
Hartman believes extending out the current tailings site would be more cost-effective, and easier to monitor and maintain. However, that proposal would also cover the headwaters of Tributary Creek which is habitat for Dolly Varden char and coho.
“We think it’s best to keep all the eggs in one basket and watch that very closely,” said Hartman. “That applies not only to the design and construction and the operational phase, but even more so for the long-term reclamation and closure phase.”
The last day to comment on the draft EIS is June 4th. VanOrmer says the Forest Service will likely issue the final EIS and record of decision on a selected tailings disposal alternative in November.