An Alaskan mining company is fighting for the right to dump its tailings straight into a fish-rich lake that feeds a salmon-bearing river.
To do so, it must first overturn a 37-year-old rule in the Clean Waters Act that bans the practice.
Coeur Alaska Limited will appear before the US Supreme Court on Monday to make the pitch for it’s Kensington gold mine near Slate Lake, north of Juneau, Alaska.
Slate Lake would be the first American lake in nearly four decades to be used as a mine waste dumping site and could set a precedent for even larger mines, such as the copper-gold mine proposed in the Bristol Bay area in southwestern Alaska.
Canada has already permitted four lakes to be used as mine tailings dump sites after a regulatory change was made in 2002. Twelve other lakes are also being considered as dumping sites across the country, the CBC reported earlier this year.
American waters were protected from this practice until a regulatory change, which was also made in 2002.
In the US, a loophole in the Clean Waters Act was used by the assistant secretary of the Environmental Protection Agency to amend regulations without legislative oversight, as in Canada.
“The Kensington mine was the first mine of this sort to get a permit not from the Environmental Protection Agency, but from the Army Corps of Engineers,” said Rob Cadmus, mining and water quality organizer for the Southeast Alaska Conservation Council.
The act has always allowed the US Army Corps of Engineers to permit construction that would put “fill” in a body of water.
“When they designed the Clean Water Act they wanted to make sure that pollutants weren’t going to be dumped in water, but they recognized that you need to put rock in the water to be able to bridge or to build a marina,” said Cadmus, “That’s what fill is.”
“(The US government) gave the power to regulate that to the Army Corps of Engineers,” he said.
“What has happened here is that the definition of what fill is has been expanded to include actions that would involve disposal of waste, meaning tailings,” he said.
The Corps usually issues permits for building docks and bridges, said Cadmus, but this is the first time they’ve issued a permit for a mine.
The Southeast Alaska Conservation Council recently appealed the Corps’ decision to allow the mine to dump tailings. The council won the appeal in the US Court of Appeals for the Ninth Circuit, but Coeur soon took the case to the Supreme Court.
If approved, a practice banned in 1972 could be legal again.
The mine processes ore through froth rotation. Crushed rock is mixed with a liquid that will float chunks of gold to the surface, which are then skimmed off the top and smelted into gold bars.
“The remaining waste is the tailings,” said Cadmus.
It contains crushed rock, water, froth-rotation agents and the ore.
“In the ore itself, there are heavy metals, aluminium and mercury in particular,” said Cadmus.
“There’s also going to be a pH level of about 10, essentially the strength of ammonia,” he said.
The proposal is to dump the tailings in Lower Slate Lake. The lake covers about nine hectares and contains fish.
“The plan would call for a dam to enlarge the lake over time and a total of 4.5 million tonnes of tailings would be dumped. It would kill all the fish and most aquatic life in the lake.
There is no certainty about when the lake would be able to suppport life again since tests were inconclusive, said Cadmus.
The lake flows into Slate Creek, which has a salmon-spawning area, and flows into Berners Bay.
“Berners Bay is a pretty important ecological area in Southeast Alaska,” he said.
It has large populations of marine mammals and salmon.
If the tailings breached the dam, “those tailings would leak down into an area that is very important to commercial and subsistence fishing,” said Cadmus.
The mining industry and conservation and native groups are squaring off in the Supreme Court case.
Aboriginal people in the Bristol Bay area state their way of life could be destroyed if dumping in lakes was permitted.
“This case concerns one particular mine,” it says, “but the impacts of the precedent set by the court’s decision will be felt by communities throughout Alaska and the rest of the (US) whose lives may be affected by other mining projects much larger than the Kensington Mine.”
The proposal clearly argues a lake be used for dumping, said Cadmus.
“They’ve put out a design for tailings disposal that would include the filling of a lake called Frying Pan Lake,” he said.
“There’s no doubt that the industry is looking at this as a way of saving money.”
Phone calls to Coeur’s Boise, Idaho, and Juneau offices were not returned by press time.
The case will be heard in Washington on Monday. A response isn’t expected until spring, said Cadmus.
“What we see now is 30 years after they’ve been operating without having to dump tailings, the industry is pushing to weaken environmental protection so they can make money and it’s easier for them,” he said, “But it’s not necessary for their survival at all.”
The industry have had their way in Canada, he said, and now they’re going for even bigger fish.
“At least on the Canadian side, there’s been a couple of lakes that have been destroyed in this manner and on the American side Slate Lake might be the first one,” he said.
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