Preliminary Economic Assessment (2011) of the Lundberg and Engine House zones was completed by Wardrop Engineering Inc. (a Tetra Tech company), based on the 2008 resource estimate by Mercator. This study determined that the combined deposits have potential to support a stand-alone, 5,000 tonne per day open pit mining and milling operation having a 10 year mine life.
Pit design criteria includes:
- 10 m benches;
- 85° face angle;
- double benching;
- 15 m catch-bench;
- overall pit slope of 50°, without inclusion of a ramp;
- 26 m ramp width, double lane (based on 90 t haul trucks);
- 17.5 m ramp width, single lane (based on 90 t haul trucks).
An approximate pushback width was determined based on:
- A Komatsu PC2000-8 diesel hydraulic shovel, loading Caterpillar 777F haul trucks.
- A minimum double-side loading width of a diesel hydraulic shovel at 26.3 m for the Caterpillar 777F haul truck.
- A 26 m haul road width.
- The proposed minimum pushback width is the sum of the minimum doubleside loading width at 26.3 m, and the haul road width at 26 m, for a total minimum width of 52.3 m.
MINE DEVELOPMENT AND PRODUCTIONS CHEDULE
The mine development used a number of push-backs, or phases, designed to meet the following objectives:
- enable the mining of high grade resource as early as possible;
- effectively reduce stripping ratio in the initial mining stage;
- balance the st ........
