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

Table 16.9 Pit Design Criteria
Item Value
Overall Pit Slope Angle 45°
Bench Height 10 m
Batter Angle 72°
Catch Bench Width 12.0 m
Benching Double
Ramp Width, Double Lane 35 m
Ramp Gradient 10%
Minimum Mining Width 40 m
Table 16.10 summarizes the calculation for the double lane ramp width complete
with allowances for safety berms and ditches.
Table 16.10 Pit Design Ramp Width Calculation
Item
Truck Parameters
Value
Selected Truck Size 225 t
Operating Width 8.3 m
Operating Width Multiplier 3.5
Double Lane Road Width
Berm
29.1 m
Tire Overall Diameter 3.6 m
Height (3/4 of largest tire) 2.7 m
Slope (H:V) 1.3:1
Berm Width
Ditch
7.0 m
Depth 1 m
Slope (H:V) 1:1
Ditch Width 2.0 m
Total Road Width 40.0 m
The proposed minimum mining width must be greater than the minimum double-side
loading width for an excavator (35 m). Based on a 21 m 3 (bucket capacity) diesel
hydraulic shovel loading 225 t haul trucks, an approximate minimum mining width
was determined to be 40 m. Mining widths throughout the open pit easily exceed this
minimum mining width requirement; only two benches at the bottom of the pit will
have a 40 m mining width. For this area, smaller equipment will be utilized.
Prophecy Platinum Corp. 16-20 1193460500-REP-R0001-02
Wellgreen Project Preliminary Economic Assessment,
Yukon, Canada