Copper Mountain mine tailings pond proposal sparks widespread concern

A B.C. mine that was fined $51,000 for unauthorized release of wastewater late last year is proposing to increase its tailings pond capacity by 70 per cent in a move that won’t automatically trigger an environmental assessment.At 155 metres high, the Copper Mountain mine’s tailings pond dam is already four times taller than the Mount Polley mine tailings dam, which caused the largest mining spill in Canadian history when it failed in 2014. Now, a proposal by the Copper Mountain Mining Corporation to increase the allowable height of the dam to 255 metres — potentially making it taller than Vancouver’s highest skyscraper — is sparking concern.The Copper Mountain mine, located about 20 kilometres south of Princeton, straddles the Similkameen River, which flows south through the province before draining across the Canada-U.S. border into Washington State’s Okanogan River. Downstream residents in B.C. and Washington are frustrated the proposed mine expansion appears to be moving forward without an environmental assessment. The expansion would also more than double the mine’s permitted discharge into the Similkameen River, from 60 litres per second of treated wastewater to 200 litres per second. The mine was fined $51,000 last November for exceeding discharge limits and contravening B.C.’s Environmental Management Act with unauthorized discharge.

Source: Copper Mountain mine tailings pond proposal sparks widespread concern