The Niobec mill currently has an average throughput of 210 mt/h, while the mine hoist has an average hoisting capacity of 260 mt/h. The mill expansion is designed to increase mill throughput to 260 mt/h, thereby matching it to mine hoisting capacity. Construction of the mill expansion is scheduled for completion during the third quarter of 2010.

The Niobec mine has traditionally been mined using a longhole open-stoping mining method, without backfill. This method leaves significant ore-grade rock behind in both vertical and horizontal pillars to support open voids created during the mining sequence. By using paste backfill made from mill tailings mixed with cement and another binder, Iamgold expects to achieve nearly complete extraction of the Niobec orebody, leaving behind almost no ore pillars. Construction of the paste backfill plant and associated underground infrastructure is scheduled for completion during the second quarter of 2010.