About 300 people in rural British Columbia, Canada are without drinking water right now after the tailings pond at a nearby mine breached, spilling more than a billion gallons of toxic waste into the environment. When the tailings pond at the open-pit Mount Polley copper and gold mine near Quesnel, B.C. breached earlier this week, it sent the equivalent of 1.3 billion gallons (the equivalent of 2,000 Olympic pools) of slurry containing mining byproducts and chemicals including arsenic, mercury and sulphur down through the mountains and into local water systems – forcing a water ban for 300 people living nearby. That number could rise as further-reaching implications of the spill are uncovered.

The water ban affects people living near Polley Lake, Quesnel Lake, Hazeltine Creek and Cariboo Creek – all of which flow into the Fraser River, the longest river in British Columbia, which flows through Vancouver and into the Pacific Ocean. But authorities haven’t yet issued a water ban for the Fraser River because they can’t confirm that any of the toxic chemicals have made it that far yet. The ban is in effect for the nearby Quesnel River and the water ban was recently extended to the city of Quesnel, where residents have been asked to avoid river water.

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“What we know so far is that debris from the tailings pond backed up a little into Polley Lake, which absorbed some of the flow, but the majority went down Hazeltine Creek, Al Richmond of the Cariboo Regional District told the Vancouver Sun. “The creek (used to be) four feet wide. Now it’s 150 feet wide.”

The cause of the breach is still under investigation, but the fact that it happened is no surprise to those in the know. According to the Vancouver Sun, concerns about the Mount Polley tailings pond date go as far back as 2011 when an environmental consulting firm did a report for the Province of British Columbia calling for an emergency plan for spills and monitoring of the pond, which warned owner Imperial Metals about the problem.

Via ThinkProgress, CBC, Vancouver Sun

Images via Cariboo Regional District