Mining News: Northern Neighbors: Mount Polley tailings dam repaired, back in use

Imperial Metals Corp. June 23 reported that the British Columbia Ministry of Energy and Mines and the Ministry of Environment have authorized the Mount Polley Mine to return to normal operations making use of its repaired and buttressed tailings storage facility. Imperial said the management and staff at Mount Polley worked in close cooperation with regulatory agencies, First Nations and members of the local communities, to repair and reinforce the tailings facility in accordance with best applicable practices identified by a panel of independent engineers. Thorough investigations by an independent engineering review panel, the B.C. Ministry of Energy and Mines, and a team from Golder Associates Ltd. – the engineer of record retained by Mount Polley – all concurred on the failure mechanism that led to the breach of the tailings dam in 2014. The updated design of the embankment in the area where the failure occurred reflects the results of these investigations. Furthermore, all the existing TSF embankments were investigated, and foundation conditions throughout were comprehensively characterized. These investigations led to modification of the embankments to assure that the stability of the structure meets or exceeds all applicable legislative requirements and guidelines. “A return to normal operations is important to the region as Mount Polley is a significant contributor to the economy, directly providing about 350 jobs, as well as supporting the local communities of Likely, Williams Lake and the surrounding region, said Imperial Metals President Brian Kynoch. “Mount Polley is committed to working with First Nations and local communities to complete rehabilitation of the areas impacted by the breach, and we thank all those involved in the rehabilitation for the excellent work that has been completed to date.” Since the breach of the Perimeter Embankment, Mount Polley has completed significant rehabilitation of the areas that were affected by the breach, and will continue necessary rehabilitation and monitoring of those areas. Imperial said research and monitoring indicates the environment impacted by the tailings breach is recovering rapidly and no long-lasting effect is anticipated.

-Shane Lasley