TORONTO (miningweekly.com) – Montreal-based Osisko Mining has increased the openpit gold reserves at its flagship Canadian Malartic project by 19,3%, after including new drilling results and running the numbers at a higher assumed gold price.

But the company cautioned that output this year and in 2012 might end up being lower than previously indicated, because of mine plan changes as a result of the new reserve numbers.

Noise-level restrictions will also mean the firm is restrained from ramping up to the full production capacity of 55 000 t/d, although the company said it is working on noise-reduction measures and is working with the Quebec government with the aim of ramping up to full operations in the third quarter.

The project now containts an estimated 10,71-million ounces of gold reserves, compared with the previous 8,97-million ounce estimate.

Total measured and indicated resources rose 5,4%, to 11,8-million ounces, while resources in the inferred category increased 150%, to 850 000 oz of gold, Osisko said.

The new numbers were calculated at a $1 000/oz gold price.

Osisko said it will give an update on the mine plan, production schedules, mine life and cost estimates for Canadian Malartic in the second quarter.

The firm plans to start production at the mine before mid-year, and had previously forecast production of 688 000 oz for 2011.