By volume it was one of the biggest mining waste spills ever recorded, and it happened just over a year ago in central British Columbia.
The earthen walls of a massive tailings pond collapsed at Imperial Metals's Mount Polley copper and gold mine, dumping 25 million cubic meters of sludge and wastewater containing arsenic, mercury, and selenium into salmon-bearing waterways. An 12.8 million cubic meter deposit of mining waste remains at the bottom of Quesnel Lake, where about one million sockeye salmon spawn each year. The long-term biological impacts on those salmon are still unknown.
On the one year anniversary of that environmental disaster — more than 1,000 kilometers northwest of the spill site — Alaskans marched in the streets of a small fishing town to protest a recently-opened copper and gold mine from the same BC company. Fishing, wilderness, and indigenous rights advocates on both sides of the border say Imperial Metals's Red Chris mine is too similar to Mount Polley and far too close to valuable Stikine River salmon stocks.
"It was really alarming," Paula Dobbyn, communications director of Trout Unlimited in Alaska, said of the Mount Polley spill. "It didn't flow into a transboundary river, but for us it showed how lax BC mining law and regulation is."
The BC government has defended its mining inspection and permitting practices, citing a Mount Polley engineering review that concluded the disaster would not have been prevented by government inspections. That report blamed the spill on unstable glacial soil underneath the tailings pond and its steeply constructed dam walls.
Critics say Red Chris has a similarly designed tailings pond: According to a 2014 independent engineering review, it is also built on top of 90 meters of sandy glacial deposits in the headwaters of the Stikine, a cross-border salmon-fishing river. What makes it different, says Rivers Without Borders campaigner Chris Zimmer, is the Red Chris mineral deposit contains copper sulfides, which can generate "vastly more toxic" acids when mined.
Steve Robertson, the vice president for corporate affairs at Imperial Metals, did not return requests for comment.
The government of British Columbia gave the Imperial Metals-owned mine a green light to begin full-scale operations on June 19. It is one of about a half dozen mining projects in various states of development in the area, and approval for it came just after Pretium's nearby Brucejack gold mine was given the thumbs up in April 2015.
"At least six, and up to 10, of these new BC mine projects are right along our border, threatening three watersheds — the Taku, Stikine, and Unuk rivers," Dobbyn said, adding about a billion tourism dollars are also at stake. "If anything goes wrong, the mines could leech pollutants into our water and destroy the economy of southeast Alaska."
A coalition of wilderness groups including Trout Unlimited are seeking an international review of the BC mining boom. When US Secretary of State John Kerry visits Alaska later this month, they'll pressure the feds to invoke the Boundary Waters Treaty, a law used by the International Joint Commission to settle cross-border water issues between Canada and the United States.
British Columbia's energy and mines minister Bill Bennett has called demands for the joint commission to get involved "premature," noting in an editorial in the Juneau Empire earlier this year that Alaskans can already participate in the province's mine review process.
Jake Jacobs, a spokesman for the ministry, told VICE News: "[T]he best way to deal with transboundary issues relating to mining is through the involvement of neighboring jurisdictions in our authorizations process."
"Even if it was the best permitting process on the planet, it's not designed to look at long-term, cumulative questions," said Zimmer. He adds Alaska's participation in mining reviews has been uneven and "at the courtesy and willingness of BC." He'd like to see more enforceable cross-border checks and balances and a region-wide review of multiple mine projects.
"Mount Polley was an education," he added, "it really exposed a lack of financial assurances to deal with aftermath and compensate injured parties."
When asked if the mines ministry is undertaking a region-wide mining review or would support an international review, Jacobs said the ministry is working toward an agreement with the Alaskan government that will allow greater cross-border involvement on proposed mine development.
Both Zimmer and Dobbyn argue the BC government has not followed its own recommendations in the wake of the Mount Polley dam failure. Report findings say new mines should implement "best available technologies" such as "dry stack" or "filtered" tailings instead of sludgy wastewater ponds.
"The independent panel's report does not say all tailings dams must be discontinued," Bennett said in the Juneau Empire. "The panel recommends relying on best practices for existing tailings impoundments, and actively encouraging best available technologies for new tailings facilities."
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