7
The estimated gain with improved ore recovery was
of approximately $3.6 million yearly with the average
numbers considered in the study for final-wall blasts con-
ducted yearly and expected average grade of 0.187% Cu.
Furthermore, the new design is also estimated to save
approximately 2% on drilling and blasting costs near the
highwalls. This cost reduction comes from a reduction in
drilling footage per ton of rock extracted due to using short
holes in the trim row, and a much-reduced need for gas
bags as accessories for air-decking. This was done without
altering the pre-established geotechnical constraints on
maximum pounds per delay allowable near geotechnically
concerning areas.
CONCLUSION AND FUTURE WORK
The main findings of this work were the cause-and-
effect relationships between pre-split drilling quality and
its potential impact in traditional designs practiced at
Capstone Copper’s Pinto Valley mine. We were able to
decrease by 71.2% the amount of material losses by using
alternate drilling-and-blasting designs that were created
considering field-collected drilling-accuracy data.
The increase in material recovery is estimated to bring
into production nearly one million pounds of copper into
the mine’s yearly production considering an average grade
after all recoveries applied of 0.187% Cu. Using a currently
conservative price of $3.6 per pound of copper, this equates
to approximately $3.6 million in extra revenue a year in
benefit for the operation. The positive monetary impact
comes with a series of other harder-to-quantify benefits,
such as cleaner walls and more effective catch benches, for
example.
Trim blasts’ drilling and blasting costs were decreased
with the new design, by drilling less per ton blasted using
short trim holes, and decreasing the need for accessories
(i.e., blast bags) by nearly two thirds on those blasts.
Enhancements to the alternate design presented
herein remain a potential for future work. Further effort to
improve pre-split drilling accuracy can and should still be
investigated. The use of different drill bit types, stabilizing
drill pipes, tools for angle setup could also be evaluated to
decrease drill-hole deviation.
ACKNOWLEDGMENTS
The authors would like to recognize the value added by
multiple professionals that supported this work, includ-
ing, but not limited to, the Capstone Copper’s Pinto Valley
Mine Management and Engineering Teams, Mike Kotraba,
and Sid Erikson.
REFERENCES
[1] Capstone Copper. Capstone Copper -Pinto Valley
Mine. [Online] 07 17, 2024. https://capstonecopper
.com/operations/pinto-valley/.
The estimated gain with improved ore recovery was
of approximately $3.6 million yearly with the average
numbers considered in the study for final-wall blasts con-
ducted yearly and expected average grade of 0.187% Cu.
Furthermore, the new design is also estimated to save
approximately 2% on drilling and blasting costs near the
highwalls. This cost reduction comes from a reduction in
drilling footage per ton of rock extracted due to using short
holes in the trim row, and a much-reduced need for gas
bags as accessories for air-decking. This was done without
altering the pre-established geotechnical constraints on
maximum pounds per delay allowable near geotechnically
concerning areas.
CONCLUSION AND FUTURE WORK
The main findings of this work were the cause-and-
effect relationships between pre-split drilling quality and
its potential impact in traditional designs practiced at
Capstone Copper’s Pinto Valley mine. We were able to
decrease by 71.2% the amount of material losses by using
alternate drilling-and-blasting designs that were created
considering field-collected drilling-accuracy data.
The increase in material recovery is estimated to bring
into production nearly one million pounds of copper into
the mine’s yearly production considering an average grade
after all recoveries applied of 0.187% Cu. Using a currently
conservative price of $3.6 per pound of copper, this equates
to approximately $3.6 million in extra revenue a year in
benefit for the operation. The positive monetary impact
comes with a series of other harder-to-quantify benefits,
such as cleaner walls and more effective catch benches, for
example.
Trim blasts’ drilling and blasting costs were decreased
with the new design, by drilling less per ton blasted using
short trim holes, and decreasing the need for accessories
(i.e., blast bags) by nearly two thirds on those blasts.
Enhancements to the alternate design presented
herein remain a potential for future work. Further effort to
improve pre-split drilling accuracy can and should still be
investigated. The use of different drill bit types, stabilizing
drill pipes, tools for angle setup could also be evaluated to
decrease drill-hole deviation.
ACKNOWLEDGMENTS
The authors would like to recognize the value added by
multiple professionals that supported this work, includ-
ing, but not limited to, the Capstone Copper’s Pinto Valley
Mine Management and Engineering Teams, Mike Kotraba,
and Sid Erikson.
REFERENCES
[1] Capstone Copper. Capstone Copper -Pinto Valley
Mine. [Online] 07 17, 2024. https://capstonecopper
.com/operations/pinto-valley/.