Unique push back exercises, practiced at Unique push back exercises, practiced at Iron Ore Company of Canada to optimize Iron Ore Company of Canada to optimize

Humphrey pit designsHumphrey pit designs

  

ALI CHAMANARA*, KAZEM ORAEE**, DAVID R. G. MITCHELL***ALI CHAMANARA*, KAZEM ORAEE**, DAVID R. G. MITCHELL*****PhD candidate and Lecturer, School of Mining and Petroleum Engineering, University of AlbertaPhD candidate and Lecturer, School of Mining and Petroleum Engineering, University of Alberta

**Professor, **Professor, Department of Management, University of StirlingDepartment of Management, University of Stirling***Senior mining advisor, Iron Ore Company of Canada***Senior mining advisor, Iron Ore Company of Canada

Eighteenth International Symposium on Mine Planning Eighteenth International Symposium on Mine Planning and Equipment Selectionand Equipment Selection

November 17, 2009November 17, 2009

IntroductionIntroduction

Designs generated by computers Designs generated by computers are not always optimum.are not always optimum.

A considerable increase in reserves A considerable increase in reserves was achieved by redesigning and was achieved by redesigning and rescheduling the Humphrey pit rescheduling the Humphrey pit production program.production program.

The total stripping ratio was also The total stripping ratio was also was also reduced marginally. was also reduced marginally.

Location Location

Labrador City and Wabush

incorporated in 1961 and 1967 Population ~ 12,000 Sub-arctic climate

http://www.labradorwest.com/

Sept-Iles, QuebecSept-Iles, Quebec

• Population 25,500• Deep-sea harbour accessible year-round• One of the three largest Canadian ports for tonnage handled

HistoryHistory 1949-Incorporation1949-Incorporation 1954-Completion of QNS&L Line1954-Completion of QNS&L Line

First Shefferville ore shipmentFirst Shefferville ore shipment 1962-Commissioning of Carol Project1962-Commissioning of Carol Project 1970-Expansion Program 1970-Expansion Program 1981-Closing of Sept-Iles beneficiation 1981-Closing of Sept-Iles beneficiation

plantsplants 1982-Closing if Schefferville operation1982-Closing if Schefferville operation 1996- Major Milestones reached 1996- Major Milestones reached

January, One Billion tonnes minedJanuary, One Billion tonnes mined December M.A. Hanna contract December M.A. Hanna contract

terminated terminated IOC becomes a stand-alone companyIOC becomes a stand-alone company

1997-North Limited acquires controlling 1997-North Limited acquires controlling interestinterest

1998-IOC becomes a 100% merchant 1998-IOC becomes a 100% merchant suppliersupplier

2000-Rio Tinto Ltd acquires North Ltd2000-Rio Tinto Ltd acquires North Ltd 2004-IOC celebrates transportation 2004-IOC celebrates transportation

milestonemilestone One-billionth tonne of iron ore shipped One-billionth tonne of iron ore shipped

on QNS&Lon QNS&L 2005-IOC celebrates its 502005-IOC celebrates its 50thth year year

Mine Evolution - Operating AreasMine Evolution - Operating Areas

Carol Lake MiningCarol Lake Mining

Two active pits: Luce and Humphrey West/MainTwo active pits: Luce and Humphrey West/Main Annual Production: ~60 Million Tonne @ Stripping Ratio ~0.58 t/tAnnual Production: ~60 Million Tonne @ Stripping Ratio ~0.58 t/t Fe: 37-40% Fe: 37-40%

LuceLow Weight Yield, Low Magnetite

HumphreyHigh Weight Yield, High Magnetite

Product Manufacturing - Beneficiating Product Manufacturing - Beneficiating PlantsPlants

Annual Capacity: Concentrator(1): 15.5-17.0 million tonnes Pellet Plant(2): 12.5 million tonnes

Annual Capacity: Concentrator(1): 15.5-17.0 million tonnes Pellet Plant(2): 12.5 million tonnes

ConcentratorConcentratorPellet PlantPellet Plant

Final Pit Design Final Pit Design OptimizationOptimization

1- Honoring the boundaries of the NPV final 1- Honoring the boundaries of the NPV final pit shell pit shell

2- Development of the mining phases for; 2- Development of the mining phases for; Operational efficiencyOperational efficiency

Connected operating areasConnected operating areas Ore/Waste options to maximize total outputOre/Waste options to maximize total output Less road/ramp building over timeLess road/ramp building over time

Phases which provide scheduling flexibilityPhases which provide scheduling flexibility The ability to schedule with few restrictive The ability to schedule with few restrictive

rules and ascertain that the path outlined is rules and ascertain that the path outlined is minableminable

Strategic Plan Value Strategic Plan Value (In (In house planning)house planning)

Provide the managers with Provide the managers with alternatives;alternatives; Benefits/consequences Benefits/consequences

Provide operational people with Provide operational people with awareness of the pit development awareness of the pit development pathpath Better judgment for work prioritiesBetter judgment for work priorities Elimination of reworkElimination of rework

Humphrey Final Pit Designs Humphrey Final Pit Designs

Humphrey Geology Cross SectionHumphrey Geology Cross Section

East Wall Push BacksEast Wall Push Backs

Spiral Push BackSpiral Push Back

Humphrey Final PitHumphrey Final Pit

ConclusionConclusion

More than 15 Million tonne increase in More than 15 Million tonne increase in reservesreserves

Stripping ratio decreased by 0.01 t/tStripping ratio decreased by 0.01 t/t Higher scheduling flexibility Higher scheduling flexibility More effective blending More effective blending Increase in iron ore concentrate due to high Increase in iron ore concentrate due to high

iron content in Humphrey reservesiron content in Humphrey reserves Increasing the operational efficiency and Increasing the operational efficiency and

hence creating better opportunities to mine hence creating better opportunities to mine Sherwood Pond reservesSherwood Pond reserves

AcknowledgmentAcknowledgment

The authors would like to thank the The authors would like to thank the mine general manger, Mr. Matt mine general manger, Mr. Matt Simpson, the mine chief engineer, Simpson, the mine chief engineer, Mr. Andrew Knight, and the senior Mr. Andrew Knight, and the senior geologist, Mark Blake, at Iron Ore geologist, Mark Blake, at Iron Ore Company of Canada for their kind Company of Canada for their kind supports. supports.