Statutory decision makers with the Ministry of Energy and Mines have authorized the Mount Polley Mining Corporation to return to full production using the tailings impoundment that breached on Aug. 4, 2104.
In a press release issued Thursday, the Ministry of Energy and Mines said the TSF has been repaired and strengthened to manage tailings.
The permit amendment authorizes the Mount Polley Mining Corporation to continue operations in previously permitted areas of the Cariboo Pit and underground workings.
Under the permit amendment the mine is authorized to process up to 22,450 metric tonnes of ore per day and store tailings in the repaired and strengthened TSF.
Prior to approval, the company’s Mines Act permit amendment application underwent a lengthy review process, including a thorough geotechnical review, a 30-day public consultation period and a detailed technical review by members of the mine development review committee (MDRC), the ministry noted.
The MDRC consisted of representatives from provincial agencies, First Nations, local governments (City of Williams Lake and Cariboo Regional District), the community of Likely, the Department of Fisheries and Oceans and Environment Canada.
The geotechnical review was completed by two senior geotechnical engineers and both found that the proposed design and construction of the repaired tailing storage facility met appropriate engineering standards for tailings facilities. Additionally, the review found that the recommendations from the independent expert panel and chief inspector of mines investigations were adequately taken into consideration for the design and operation of the repaired and reinforced TSF, including conducting adequate site analysis, having defined quantified performance objectives, establishing an independent tailings review board, appointing a qualified individual responsible for oversight of the TSF.
In the months since the breach, the Mount Polley Mine Corporation has completed repairs and reinforcement work on the TSF, including extensive foundation investigation and additional buttressing of the main and perimeter embankments. The company has also established an Independent Tailings Review Board (ITRB) consisting of four professional engineers. The ITRB has full-independent oversight over all aspects of the design, construction, operation and closure planning for the Mount Polley Mine TSF.
As a condition of the Mines Act restricted re-start permit amendment authorized on July 9, 2015, Mount Polley Mining Corporation must submit a draft technical assessment report in support of the long-term water management plan to government by June 30, 2016, in order to continue operations.
Minister of Energy and Mines Bill Bennett is scheduled to address media at 3 p.m. Thursday