The following associated overall slope geometry was recommended by WAI:
- Berm width: 5.5 m;
- Bench height: 15 m;
- Bench face angle: 66° and 75°;
- Inter-ramp angle: 51° and 58°; and
- Geotechnical berm: 9.5 m.
The bench face angles in the final designs vary between 60° and 75°, with 8 m berm widths to comply with local regulations and to allow mechanised cleaning. The inter-ramp angles (IRA) of around 51° and 58° for the various design sectors (i.e., Sectors 1 to 4), were flattened slightly to accommodate bench width and aligned with the WAI bench geometry recommendations. The IRA for the fault zone was reduced to 45°.
In the revised 2020 pit design it was noted that the final highwall reaches a height of 375 m, a moderate highwall height increase of approximately 1.4%.
The Tulkubash 2020 EOY open pit design is composed of three separate pits arranged along the strike of the orebody over 2 km. The pits are situated in steep, mountainous terrain at elevations of 2,300 masl to 2,800 masl. The deposit is divided up into two zones, the Main Zone and the Mid Zone.
The Main Zone Pit is situated at the southwestern end of the mining area. It is the single largest pit accounting for over 90% of the reserve by both tonnage and contained gold. The Main Zone Pit hosts a reserve of 19.4 Mt ore grading 0.86 g/t Au, containing 538 Koz Au. Associated with the ore is 50.4 Mt of waste resulting in a strip ratio of 2.6:1 ( ........
