Lubambe is an underground operation utilising the Longitudinal Room and Pillar mining method.
The current mining method employed is a variant of room and pillar ‘modified room and pillar’ which also falls under open stoping methods (unsupported underground mining methods).This method has stope designs of 20-25 m with 6m rib pillars and 5m sill pillars that are not designed to hole.
The mining sequence of modified room and pillar is as follows:
- the excavation is mined to completion for ore development with primary support installed;
- thereafter secondary support is installed;
- production drilling commences, and
- lastly stoping is conducted.
The firing sequence used has the following sequence:
- Ring 1 is fired;
- Rings 2 and 3 are taken together;
- Ring 4 to the last ring in the panel are fired in a mass blast.
This firing sequence is adopted for the whole mine but subject to change upon geotechnical recommendation if there are ground condition issues in the area.
Lubambe Studying Alternative Mining Method
The current mining method of Longhole retreat stoping in the flatter dipping (<40) areas is not entirely appropriate, due to in the high dilution that it attracts and the low dip angle affecting ore recovery. The proposed mining method Inclined Room and Pillar (IRP) for these flatter areas is more selective and would target a higher production grade by reducing waste diluti ........
