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Pebble environmental impact statement fails to consider a mining catastrophe

  • Author: Anne Coray
    | Opinion
  • Updated: April 14, 2019
  • Published April 14, 2019

With the upcoming Anchorage hearing on April 16 and the written comment period ending on May 30, Alaskans should know that there is no reference to the possibility of a catastrophic failure with Pebble in the Draft Environmental Impact Statement. There should be.

Pebble cannot “ensure” anything. Nature creates … floods, earthquakes, volcanoes, cyclones. Engineers make mistakes.

Check out: , a chronology of major tailings dam failures around the world.

Following are highlights of some disasters.


BHP Billiton, the world’s biggest mining company, is “responsible for Brazil’s largest environmental disaster in history, when, on November 5, 2015, two of the dams encompassing its toxic tailings ponds burst, suddenly releasing millions of tons of poisonous slurry into the Rio Doce river, killing all aquatic life downstream.”


Rio Tinto, the second largest company, took its name from the Rio Tinto River. The company took over management of the mines in 1873.

“The Rio Tinto watershed was … prior to the era of open pit sulfide mining, a thriving commercial fishing area, but ever since the mining corporations began exploiting the area …, the estuary fed by the Rio Tinto no longer has any fish or other aquatic life in it.”


2019: Brumadhino. Seeing actual clips would serve the reader well.

“ ‘Rio Paraopeba has started to die,’ … a video clip (showed) oxygen-deprived fish leaping out of the turbid water and flapping their last on the land. The immediate threat is to the 174 miles of Paraopeba River. Vale (the mining company) insists the problem will not spread to the São Francisco basin, but … in this region, 64% of fish species are found nowhere else on Earth. “


September 2014. Mount Polley, British Columbia. (Yes, Pebble is a Canadian company.)

“A tailings dam collapsed at an open pit copper and gold mine tailings dump, sending huge volumes of toxic waste into critical waterways 370 miles north of Vancouver. The environmental catastrophe wreaked havoc … initiating an emergency drinking water ban, severely damaging the region’s important sockeye salmon habitat.”


August 2014. 25 miles across the Arizona border, “Grupo Mexico’s Buenavista copper mine in Canenea, Sonora, had a tailings failure that poured 10 million gallons of copper sulfate acid into (the Rio Sonora) that supplies water to tens of thousands of people … The river of orange poison reportedly is killing livestock and wildlife.”

Summitville Mine, Colorado, 1991

“The height of the containing dike for cyanide leach solutions … was below the level required for snowstorms and spring runoff; broken pump lines and a French drain beneath the leach pad caused cyanide-contaminated solutions to be released into the local watershed.”

• Release of toxic metals and cyanide to the Alamosa River

• most aquatic life killed along 17-mile stretch of river to Terrance Reservoir

• Iron, aluminum, zinc, copper: trace metals that killed fish

Iron Mountain Mine, Redding, California

From the 1860s to 1963, the Iron Mountain Mine in Redding, California yielded silver, gold, copper, zinc and pyrite. Mining techniques included open slope and open pit. When the mountain fractured, mineral deposits were exposed to oxygen, water and certain bacteria, that resulted in acidic mine drainage. Numerous fish kills occurred at what is now a Superfund site.

“The flow from this chemical cauldron into the Sacramento River and its tributaries was devastating … Before the creeping acid was contained, it was as bad for the environment as 100 oil refineries pouring petroleum into a salmon spawning stream. / In 1988, a sudden surge of power at a U.S. Bureau of Reclamation plant sent 2,000 cubic feet per second of metal-laden water flowing out of the Keswick Reservoir, turning the Sacramento River red all the way to Hamilton City, 100 miles away. / The shaft leads deeper inside where … the puddled water is sulfuric acid, concentrated enough to melt an aluminum ladder.”

Bingham Canyon , Utah

“Bingham is an open-pit mine — a gigantic hole in the ground. The landslide … was the collapse of one of the pit walls … Approximately 165 million tons of rock shifted, causing a highly localized earthquake measuring 5.1 Richter. It damaged or destroyed roads, power lines, and other infrastructure.”

Berkeley Pit, Montana

November 1995 : “The old mine … had been inactive for decades, but it was full of dissolved heavy metals and highly acidic water. 342 geese died … autopsies showing perforated esophageal ulcerations from drinking the water.”

Nov. 28, 2016: “… an estimated 10,000 migrating snow geese landed on the permanently-poisoned toxic water and began dying. Witnesses said that the lake was ‘white with birds.’

Severe poisoning with heavy metals are essentially incurable … even in humans, because those toxins are so rapidly lethal to nerve, liver and kidney cells.”

Red River, New Mexico

After 36 years of molyebdenum mining, the site contains … “328 million tons of waste rock, a 1,500-foot-deep open pit, (and) collapse zones from underground tunneling. A nine-mile-long pipeline carries tailings slurry from the mill to lagoons, (i.e.) lakes of acidic waste, located on the other side of Questa. / In the early 1980s, the Red River began to turn a cloudy blue, a symptom of acid drainage and high metal content.” / Even early on, “hundreds of spills from shoddy tailings pipelines poured into the Red River…until then, the Red had been known as one of the best trout streams in the West. Suddenly, the fish were gone.”

It’s time to heed history.

Pebble claims it will be constructing a smaller mine. But expansion is already planned, through an obscure application with the state of Alaska. Also in phase two, they plan to use cyanide to separate gold. Funny, how the Draft Environmental Impact Statement states “No cyanide.”

The water, once polluted, will need to be monitored in perpetuity. That means forever.

Anne Coray lives at her birthplace on Lake Clark. She and her husband have relied for years on the subsistence fishery.

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