This statistic shows the total mineral discharges to surface and groundwater in British Columbia, Canada from the Mount Polley dam breach in 2014. In that year, the combined discharges of arsenic,
cadmium, lead, nickel, selenium, antimony, chromium, cobalt, copper, manganese, mercury, thallium, vanadium, and zinc to groundwater and surface water from the Mount Polley dam breach amounted to 41,040.1 metric tons.
Mount Polley mine disaster
The Mount Polley dam breach, also referred to as the Mount Polley Mine disaster, was a breach of the Mount Polley mine's copper and gold tailings storage facility/pond. It began on August 4, 2014 in the Cariboo region of British Columbia, Canada, and leaked several years' worth of mine waste into the nearby Polley Lake, before continuing on to Quesnel Lake through Hazeltine Creek. When the tailings pond was fully drained by August 8, 2014, the
water levels in Polley Lake had risen by 1.5 meters, and Hazeltine Creek expanded in width from two meters to a fifty meter wide area of mud, felled trees, and other debris.
Aftermath of the Mount Polley damn breach
These events are considered to be one of the largest environmental disasters in recent Canadian history. Imperial Metals, the mining company that owns the Mount Polley gold and copper mine, is said to have operated the tailings pond over its capacity since 2011 or earlier. In the areas directly around and including Hazeltine Creek, Polley Lake, and Quesnel Lake there has been a "do not use" notice put on
water consumption and is expected to last indefinitely; boiling the water in this area is insufficient to make it safe to drink. One of the most significant safety risks associated with the
water in this area are the dangerously high levels of
zinc. Mining operations at the Mount Polley Mine recommenced on August 5, 2015.