prevention and control of spontaneous combustion - Mining and

• The survey department will design the pattern on Modelmaker, showing the hole position
and general depth. The plan is then exported from the survey department into the Aquila
System on the Pit Viper and DMM2.
Test holes
• Test holes are drilled in undermined areas
• These holes are drilled 25m apart on the buffer perimeter
• These holes should hole. All the holes must be plugged by the drill operator, directly after
the drill has moved off the hole position.
Infill holes
• The surveyor will extract and collect all the data for the pre-split and test holes from the
Aquila system
• The strata logging on each hole will determine the top of seam position
• He will build an infill plan and model, showing the exact position and depth of each hole to
be drilled.
o The 4 seam overburden infill holes must be drilled to the top of 4 seam lower
level, minus 50cm.
o The 2 seam interburden in-situ infill holes must be drilled to the top of seam,
minus 1m
o The 2 seam interburden undermined holes must be drilled to the top of seam,
minus 2.5m
• The operator will ensure that every hole is drilled at the right position to the predetermined
depth. Any hole holed into underground workings must be sealed and marked before any
other hole is drilled
• Sealing will be done with an upside-down cone pressed down into the hole and dirt placed
in the cone. Another cone will be placed on the hole, facing upwards, with a stake
indicating the hole number and holed depth. The drill operator is responsible for this
procedure. Each hole that holes must be reported to the supervisor
• All infill holes must be re-drilled 1m away on spacing line and 2m shorter than the original
depth
• All buffer holes must be drilled with 200mm rotary bits and infill holes with 250mm bits
• Table 1 indicates the drill patterns
• A and B line infill holes next to the void will only be drilled in daylight hours
• If for any reason, i.e. cracked floor, hole on gradient, close to highwall, etc., a hole cannot
be drilled at the required position, the supervisor will move the hole to a safe position, plot
the position on the plan, log the change and notify the mine overseer. The survey
department will import all the reports from the drills and keep them on file
• The drill supervisor will report the production and any anomalies to the mine overseer on a
daily basis.
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