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Long Hole Stoping Comparison Comparison between Small hole Tophammer - 45mm and Large Specific Drilling is required in order to maintain Powder Factor Small Hole ITH – 60mm Ability to Drill a single row of holes in center of stope is assumed Basic assumptions made for method comparison Powder Factor used is the same as that of conventional Powder Factor used is the same between compared methods Stope Span is the same between compared methods

Plan Section of Raise & Stope

Dip Section of Raise & Stope

Blast Pattern – Tophammer Drill Hole Diameter = 45mm Disadvantage High Specific Drilling = High Cost Small Stand-Offs to Contacts Complex Rig setup and moving Advantage Do not require defined contacts

Blast Pattern – Tophammer Drill Hole Diameter = 45mm Disadvantage High Specific Drilling (small holes) = High Cost Small Stand-Offs to Contacts Complex Rig setup and moving Advantage Less Drilling than 5 hole dice require medium defined contacts

Blast Pattern – ITH Drill Hole Diameter = 60mm Disadvantage Require defined contacts Advantage Low Specific Drilling = Low Cost Large Stand-Offs to Contacts Easy Drill Rig setup and moving

Long Hole Stoping Comparison Common Results

Long Hole Stoping Comparison Common Results – not recalculated from previous input

Long Hole Stoping Comparison 6m Ledging20m Full Span Stoping