Gold mineralization in the Meadowbank deposits can be classified in two main deposit types: iron formation hosted gold and Lode gold (disseminated/replacement style); although several different styles of mineralization can be commonly found in the same area. The iron formation hosted deposits are represented by Portage and Goose, while the disseminated/replacement lode gold deposits are best represented by Vault.

The mineralization in the Portage and Goose areas at Meadowbank is iron formation hosted. Typically, gold in these types of deposits occurs as fine disseminations associated with pyrite, pyrrhotite, and arsenopyrite, or in cross-cutting quartz veins and veinlets hosted in iron formations and adjacent rocks within volcanic or sedimentary sequences. Mineralization is generally within, or near, favourable iron formations.

The Vault deposit can probably best be described as a disseminated/replacement lode gold deposit. Disseminated and replacement gold deposits comprise mainly stratabound auriferous bodies of disseminated to massive sulphides, commonly pyritic, that are hosted either by micaceous and/or aluminous schist, derived from tuff and volcanic sandstone or by carbonateclastic sedimentary rocks; spatial associations with granitoid rocks are common (Poulson, 1996).

Meadowbank conducts surface mining from a series of three pits all within 7 kilometres of the processing plant.

The mine works year-round, using conventional drilling, blasting, truck and shovel methods. To minimize acid generation, the sulphide-bearing waste rock is encapsulated in permafrost and capped with an insulating layer of neutralizing rock.

The 11,000-tonne/day gold processing plant at Meadowbank uses conventional technology adjusted to the Arctic climate.

Any “free gold” is removed by a gravity circuit. The remainder is leached using cyanide, with the gold captured using carbon-in-pulp technology and electrowinning cells. Gold-plated cathodes and gravity concentrate are smelted in an induction furnace and poured as doré bars. The plant includes both a cyanide recycling thickener and an air-sulphur dioxide cyanide destruction circuit to ensure that no cyanide escapes to the environment. All water from the tailings pond is pumped back to the plant for reuse, making this a zero-discharge system.

The run-of-mine ore is transported to the crusher using off-road trucks. The ore is dumped into the gyratory crusher or into stockpiles designated by ore-type. The feed from the primary crusher is conveyed to the cone crusher in closed circuit with a vibrating screen. The crushed ore is delivered to the coarse ........