Wellgreen Project Preliminary Economic Assessment ... - OTCIQ.com

OVERALL O PEN P IT SLOPE ANGLE
Tetra Tech used an overall pit slope angle of 45°, in the absence of geotechnical
data normally used to determine pit slope angles.
PIT O PTIMIZATION RESULTS
Thirty-six nested pit shells were generated by varying the revenue factor (RF)
(multiples and fractions of the selling prices) from $5.41/lb nickel to $12.98/lb nickel
with $0.22/lb increment. Pit Shell 26 represents the base case price, and is
highlighted in Table 16.4. Figure 16.1 shows the NiEq content in the pit shells
generated using the range of prices mentioned above. As Figure 16.1 indicates, the
metal content in pit shells increases as the metal price increases, due to a change in
both the size of the optimum pit and the change in cut off grade. The slope of the
line in Figure 16.1 shows the sensitivity of the pit size to the price. The steeper area
of the graph represents the range of price that has bigger influence on the size of the
pit. The slope of the line is steeper for the pit shells less than $8.80/lb NiEq. The
increase in metal content decreases after this point. Based on this model for prices
less than $5.4/lb NiEq, there is little valuable rock to be mined.
Figure 16.1 Nickel Equivalent Content in Pit Shell Based on Nickel Equivalent
Price
Prophecy Platinum Corp. 16-4 1193460500-REP-R0001-02
Wellgreen Project Preliminary Economic Assessment,
Yukon, Canada