MacLean, a former Inco employee who worked in Sudbury, developed drawpoint obstruction clearance machines for block caving rigs, including blockhole jumbos in the late 1970s.
These rigs helped operators break drawpoint boulders below the brow by utilizing high-pressure water impulses.
an offset herringbone drawpoint
layout to facilitate the use of electric loaders.
The Koala mine was developed with sublevels spaced 20 m apart vertically and 5 m x 5 m drawpoints
on a 14.
Hand over of drawpoints
has been consistent at a rate of one per week, since the end of April.
Mining of the initial Central Block by front caving also experienced stress related difficulties during the quarter and early dilution in some drawpoints
Once a concrete plug has been set beyond Sub Vertical 1 Shaft, and all the drawpoints
in the area have been sealed with grout, it will be possible to plan Phase II of the recovery program.
The improvement in grade was achieved through the adoption of stringent grade control measures which included stopping low grade reclamation drawpoints
and the placing of tonnage constraints on sub-level caving stopes.