~ DEVELOPMENT
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> HAULAGE

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6320 BERM

6275 BENCH

6230 BENCH

SHOVEL
3 OPERATION

SECTION A-A'

300)

FIGURE 5— Minimum bench width for efficient operation of current waste stripping equipment.

input is required from sales, mine, mill, geology and
engineering in order to optimize this annual mining
plan. Due to the preliminary status of fibre distribu-
tion projections, it is a prime function of mine plan-
ning to maintain the maximum degree of flexibility to
compensate for deviations in grade and length of fibre
from initial predictions. The annual mining plan is
reviewed and revised quarterly. A bar chart for the
yearly period is drawn up, with the added provision
for comparing actual production with scheduled pro-
duction.

Short-term mining plans are detailed to cover revi-
sions to sales, mining and milling requirements within
the general yearly mining plan parameters, and are
reviewed at a monthly meeting of mine, mill, geology
and engineering personnel. The presentation consists
of a phase composite showing ore availability in terms
of grade, ore tonnage and fibre. Proposed ore and
waste areas for monthly periods are outlined on the
composites and summarized in a computer printout.

Engineering Control

Following development of mining plans and sched-
ules, it is imperative that these schedules are adhered
to as much as possible. To supplement mine super-
visory direction, engineering and survey control is
supplied through a fully equipped field office at the
mine site.

On-site engineering functions include blast layout
design, design of temporary bench and haulage access,
calculation of monthly mining quantities and comple-
tion of resulting reports, survey supervision, and liai-
son with mine, geology and engineering personnel to
coordinate short-range objectives and survey require-
ments.

Reconciliation & Evaluation of Reserves

The effectiveness of an ongoing mine planning sys-
tem lies in the accuracy of the initial prediction/
simulation. To evaluate the prediction/production rela-
tionship, daily observations and measurements are in-
corporated into monthly reports for each ore and waste
bench, showing initial reserves, tons or yards broken,
tons or yards mined, geological reclassification, pro-

duction reclassification, tons or yards deferred to sub-
sequent phases, broken balance remaining and solid
balance remaining.

Two algebraic equations have been derived from the
basic ‘Reserves —Mined = Balance Remaining’ equa-
tion and are used monthly to ensure that calculations
are kept within acceptable limits for both ore and

waste:
Broken Geol. recl.
Fate alee
this month this month
(
end prev. month
(stent bal.

It, ea remaining
Unbroken
remaining
Mined
— |{ this at end
month

at end this month.

Production

stomalunecls

) (ve month
this month )

Geological reclassification is the variance between
the ore reserve ore/waste contact and the as-broken
contact and is used to evaluate the accuracy of ore
reserve predictions. Mining reclassification is an
evaluation of the recovery of material broken as ore.

The requirement that all direct and indirect meas-
urements must satisfy the above equations yields an
appraisal of ore reserves and mining performance
within acceptable limits. A similar, but necessarily
more detailed, exercise to evaluate ore grade-block
projections is pending.

Computer Applications

Prior to the computer application, exercises such as
changing the reserve cut-off grade or re-appraising
ultimate pit limits required the laborious manual cal-
culation of weighted averages involving weeks to
months of concentrated effort. The present application
of the computer system to accelerate and widen the
scope of mine planning resulted from a 1975 review of
the mine by consultants. Two basic systems to facil-
itate mine planning have been evolved. The first was
developed to accelerate the calculations of ore reserves,
mining increments and mining schedules. The second

at end prev. month
Deferred

al
this month

Broken bal. at
+ { Broken
this month

20 —