ZINC DIVISION: New Mine, Different Strategy: Bell Allard Mine
The Bell-Allard mine near Matagami, Que., is typical of many Noranda zinc mines. The $119-million underground development went into operation in June 1999 and began commercial production in January of this year, based on reserves of 3.3 million tonnes grading about 13% Zn and 1.5% Cu. At least 175,000 tonnes of zinc and copper concentrates will come from the mine in each of its five years of operation.
This high-grade, short-mine-life strategy also applies to the former Isle-Dieu mine in the same region, and several other small projects in northern Quebec. Ore is where you find it and what the market climate defines. The promise of exploration projects, such as the newly discovered Perseverance deposit near Matagami, may support future mines with similar strategies.
Bell-Allard is the latest in a long line of producers that have supplied ore to the Matagami concentrator. Bell-Allard replaces tonnage from the Isle-Dieu mine, which operated from 1988-97. Isle-Dieu and Norita-East provided ore to the mill after the Mattagami Lake, Orchan and Norita deposits were exhausted.
The Matagami mill was built shortly after Noranda acquired interests near Matagami in 1957. It retains much of its original character. Ore is concentrated using ball milling, two-stage differential flotation, filtering and drying. Copper concentrate is dewatered using a pressure filter, but zinc concentrate is still passed through disc filters and an oil-fired rotary dryer. Tails are impounded and effluent treated to remove metals before release. In the last few years mill automation has been considerably upgraded, which makes this concentrator highly effective in process control, from crushing to concentrate dewatering.