ISKUT, B.C. — A third-party review into the design of a northwestern B.C. gold and copper mine says it has the potential to cause significantly more environmental damage than the Mount Polley breach.
Engineering company Klohn Crippen Berger has made 22 recommendations for Imperial Metals' Red Chris mine, 500 kilometres north of Terrace, saying the tailings dam design is feasible but there are issues that must be addressed.
The report says one large flaw is the permeability of soil on which the dams would be built, noting it could cause damaging water leaks if the planned installation of a fine-grained tailings blanket isn't enough.
It also suggests that designers carefully monitor the water balance for their tailings impoundment, and complete a risk assessment around the effects of another nearby landslide.
It also recommends increased documentation, monitoring and investigation into the Red Chris mine tailings dam site, while noting that reasons behind the Mount Polley spill aren't yet known, so any technical lessons can't yet be applied.
The Tahltan Central Council instigated the review, and it was funded by Imperial Metals after the company's Mount Polley mine failed in August, sending millions of cubic metres of wastewater and silt into a network of salmon-bearing lakes and rivers.
