University of Saskatchewan of S GEOE498.3 Fall 2… · Rock Mechanics This course incudl ... GeoE...

University of SaskatchewanUniversity of Saskatchewan

Geological EngineeringGeological EngineeringGEOE 498.3GEOE 498.3

Introduction to Mineral EngineeringIntroduction to Mineral Engineering

Trevor EaglesTrevor EaglesMine ManagerMine Manager

ColonsayColonsay MineMineMosaicMosaic

Course StructureCourse StructurePart A (7 Lectures) Mine EngineeringPart A (7 Lectures) Mine EngineeringPart B (7 Lectures) Metallurgical Part B (7 Lectures) Metallurgical EngineeringEngineering

Term ProjectTerm Project

GeoE 498Introduction to Mining and Mineral Processing Engineering

Lecture Notes

T 2

Geological EngineeringCivil & Geological Engineering

University of Saskatchewan

G e o E 3 1 5 .3 - 2 0 0 9R o c k M e ch a n ics

Th i s c o u r s e i n c lu de s a n i n t ro d u ctio n t o m in i n g a n d m ine r a l p r o ce ss in g . T h i sc o u rs e p r o vide s th e s tu de n t w i t h a b a s i c u n d er stan d i n g o f m in i n g e n g i ne er i n ga n d th e m i n in g in d us t r y. T h e m in i n g c om p o n e n t o f th e c o u r s e w il l in t ro d uc et h e d r i l l a n d b la s t c yc l e , m in i n g m e th o d s a n d th e e c o n om i c e valua t io n o fm in e ra l p r o pe rt ie s . T h e m in er a l p r oc es s e n g in e er in g c o m p o ne n t w i l li n t ro du c e m in er a l s e p ar a ti o n p r o c es se s in c lu d i n g g r a vi t y, e l ec tro s ta ti c a n df l o ta ti o n s e pa r at io n .

M a rk ing S c he me

A s s ig nme nt s 2 0 %M id- te rm 3 5 %F ina l 4 5 %

A s s ig nme nt sG ro up a s s ig nm e nt s w ill be g ive n t o he lp e x pla in t he d if fe re ntf a c t o rs c o ns ide re d in t he de ve lo p m e nt o f a m ine .

GeoE 498 - 2010

Introduction to Mining and Mineral Processing Engineering

Note - You must receive a grade of 50% or higher in at least one of the midtermor final exams in order to achieve a passing grade in this course.

- All assigned work is mandatory. Failure to attend or complete any of the assignments will result in a final grade of less than 50% for the courseunless alternate arrangements are specifically approved by the instructor.

- Alternate times to write midterm examinations will not be consideredexcept in the case of illness or a conflict with other university relatedactivities.

- Alternate times to write final examinations cannot be accommodated. Ifa student misses a final exam, application must be made to the Dean'soffice to write a deferred exam.

- Students planning on registering with the office for Disability Servicesfor Students (DSS) must do so by January 30.

ACADEMIC HONESTY EXPECTATIONS: This course will conform to the academic requirements and standards for undergraduate courses, including:

• Rules of Student Appeals in Academic Matters (see http://www.usask.ca/university_council/reports/12-06-99.shtml), and

• Academic Honesty (see http://www.usask.ca/honesty/). For further information, see the attached information sheet on Guidelines for Academic Honesty entitled “Writing it Right”.

GeoE 498Introduction to Mining and Mineral Processing Engineering

These course notes are a compilation of work conducted by many people. Some of the notes have been taken from the Laurentian University coursenotes on “Introduction to Mineral Resources Engineering developed by Dr.Amaratunga and Dr Hudyma as well as the notes from the University ofWestern Australia developed by Chris Langille. Notes have also been takenfrom the following text books:

Introductory Mining Engineering, H.C. Hartman, John Wiley & Sons,1987.

Mineral Processing Technology, B.A. Wills, Pergamon Press, 1991.

Rudiments of Mining Pracitce, C.E. Gregory, Trans TechPublications, 1983.

Mine Engineering OutlineMine Engineering Outline

Mining Terms and DefinitionsMining Terms and DefinitionsGeologyGeologyProject / Operation ManagementProject / Operation ManagementU/G Mining MethodsU/G Mining MethodsInfrastructureInfrastructureOpen Pit Mining MethodsOpen Pit Mining Methods

Term Project Term Project –– Mine EvaluationMine Evaluation

Mining TermsMining TermsSustainable DevelopmentSustainable DevelopmentCommon Mining TermsCommon Mining TermsMining Methods Mining Methods –– O/P vs. U/G; Hard Rock vs. Soft O/P vs. U/G; Hard Rock vs. Soft RockRock

Mineral EconomicsMineral Economics

Underground Mining MethodsUnderground Mining MethodsBulk vs. SelectiveBulk vs. SelectiveReasons for Selection (Geotechnical, Geometry, Value, Reasons for Selection (Geotechnical, Geometry, Value, Grade, Dilution Control, Skill of work force, health and Grade, Dilution Control, Skill of work force, health and safety, etc)safety, etc)Mining Equipment (mobile)Mining Equipment (mobile)

Tunneling MethodsTunneling Methods

U/G InfrastructureU/G InfrastructureShafts (production and Service)Shafts (production and Service)Ore FlowOre FlowAir/WaterAir/WaterVentilationVentilationMaintenanceMaintenanceWarehousing and SuppliesWarehousing and SuppliesElectrical and CommunicationsElectrical and Communications

Drilling / BlastingDrilling / Blasting

Project and Operations ManagementProject and Operations Management

ScopeScopeScheduleScheduleCostCostStagegateStagegateWBS (Work Breakdown Structures)WBS (Work Breakdown Structures)Project ChartersProject ChartersEconomicsEconomicsDifferential NPVDifferential NPV

Open Pit MiningOpen Pit MiningTypes of Types of o/po/pSelection criteriaSelection criteriaStrip Ratio (geotechnical, safety factor, ore/waste)Strip Ratio (geotechnical, safety factor, ore/waste)Pit Geometry, push backs and bench heightsPit Geometry, push backs and bench heightsEquipmentEquipmentWaste dumps and Stock pilesWaste dumps and Stock pilesInfrastructureInfrastructure

Assignment / Tutorial # 6Assignment / Tutorial # 6

Tutorial Tutorial Guest Lecture (Coal)Guest Lecture (Coal)

AssignmentAssignmentStrip Ratio ExerciseStrip Ratio ExerciseEquipment SelectionEquipment SelectionNPVNPV

Introduction to MiningIntroduction to Mining

Sustainable DevelopmentSustainable Development

Mining companies recognize that in order to be successful, they Mining companies recognize that in order to be successful, they need a good corporate image.need a good corporate image.

Many large pension funds will only invest in corporately responsible companies.

Companies do business in many regions of the world and deal with many levels of government. In most cases, their reputationproceeds them.

Mining companies want to be welcomed by the communities they do business in and the governments they deal with.


An example of a sustainable development statement is:

“Meeting the needs of our stakeholders today, while preserving choices for future generations to meet their needs."

Four typical key measures of success are:

•A safe, healthy and rewarding workplace

•A clean environment

•Supportive communities

•Outstanding financial performance


••Injuries cost moneyInjuries cost moneyIncreased insuranceIncreased insuranceIncreased WSIB feesIncreased WSIB feesRisk of finesRisk of finesIncreased presence of Gov. inspectorsIncreased presence of Gov. inspectorsReduced productivityReduced productivityEnvironmental non performance cost moneyEnvironmental non performance cost moneyRisk of finesRisk of finesIncreased presence of Gov. inspectorsIncreased presence of Gov. inspectorsClean up costsClean up costs


••Supporting Communities PaysSupporting Communities Pays

Fund hospitals, Education, non profit organizations, Fund hospitals, Education, non profit organizations, parks, Hire locals, Support local businesses, etc.parks, Hire locals, Support local businesses, etc.

Communities are more likely to welcome Communities are more likely to welcome companies with a positive history.companies with a positive history.

Miners and Mining professionals are more likely Miners and Mining professionals are more likely to work for a safe, responsible company.to work for a safe, responsible company.

SafetySafetyIs mining dangerous?Is mining dangerous?

A danger is an unmanaged hazard. If a hazard is A danger is an unmanaged hazard. If a hazard is understood and managed, the Risk is significantly understood and managed, the Risk is significantly reduced.reduced.

Risk = Impact x ProbabilityRisk = Impact x Probability

Mining has many potential hazards, but with proper Mining has many potential hazards, but with proper controls in place, it is a safe occupation.controls in place, it is a safe occupation.

Why do we Mine?If it can’t be grown, it has to be mined.

Base MetalsPrecious Metals and GemsFuelIndustrial Materials

Mining is the only source for the minerals and materials that are required to maintain the high quality of life we enjoy in the modern high–tech world in which we live.

How many Minerals are there in a How many Minerals are there in a typical Computer???typical Computer???

Minerals In Typical Computers

Computer Component Element/Compound Mineral Source

MonitorPhosphorescent Coating -Transition Metals

ZnS - Zinc Sulfide Zn, S Sulfur, Hemmimorphite, Zincite, Smithsonite, Franklenite

Ag - Silver Ag Ag, Pyrargyrite, CerargyriteCl - Chlorine Cl HaliteAl - Aluminum Al Bauxite

Cu - Copper CuChalcopyrite, Boronite, Enargite, cuprite, malachite, azurite, chrysocolla, chalcocite

Au - Gold Au AuY2O2S - Yittrium Sulfate YEu - Europium Eu

KF,MgF2):Mn Potasium-Magnesium Fluorite: Manganese K, F, Mg, Mn

Alunite, Orthoclase, Nephelite, Leucite, Apophullite; Fluorite, cryolite, vesuvianite, ;lepidolite: Dolomite, magnesite, espomite, spinel, olivine, pyrope, biotite, talc, pyroxenes

(Zn,Cd)S - Zinc Cadmium Sulfide Cd

Zn2SiO4:Mn, As - ZincSilicate, Manganese, Arsenic As Realgar, Orpiment, Niccolite, Cobalite, Arsenopyrite, Tetrahedrite

Gd2O2S:Tb - Gadolinium Sulfate:Tebrium Gd, TbY2SiO12:Ce - Yitrium Silicate: Cerium Ce Monzanite, Orthite

CRT Glass

Pb - Lead Pb Galena, cerussite, anglesite, pyromorphite

SiO2 Si QuartzPlastic Case, KeyboardThermoplastic - Polypropylene, PVC

CaCO2 _additive Ca Calcite, gypsum, apatite, aragoniteTiO2 - White Pigment Ti Rutile, Ilmenite, TitaniteAmonium Polyphosphate P Apetite, Pyromorphite, WavelliteLCD, Liquid Crystal Display Monitors


Thin Film Transistors Si QuartzFerro Electric Liquid Crystal Fe HematiteIndium Tin Oxide Sn Cassiterite,

In Sphalerite (Commonly found with Zinc)

Metal CaseIron Fe Magnetite, LimoniteFlat Screen Plasma Display MonitorsGlass Si Quartz


ZnS - Zinc Sulfide Zn, S Sulfur, Hemmimorphite, Zincite, Smithsonite, Franklenite

Ag - Silver Ag Ag, Pyrargyrite, CerargyriteCl - Chlorine Cl HaliteAl - Aluminum Al Bauxite


Au - Gold Au Au

Y2O2S - Yittrium Sulfate Y EuxeniteEu - Europium Eu Euxenite

KF,MgF2):Mn Potasium-Magnesium Fluorite: Manganese K, F, Mg, Mn

Alunite, Orthoclase, Nephelite, Leucite, Apophullite; Fluorite, cryolite, vesuvianite, ;lepidolite: Dolomite, magnesite, espomite, spinel, olivine, pyrope, biotite, talc, pyroxenes

(Zn,Cd)S - Zinc Cadmium Sulfide Cd

Zn2SiO4:Mn, As - ZincSilicate, Manganese, Arsenic As Realgar, Orpiment, Niccolite, Cobalite, Arsenopyrite, Tetrahedrite

Gd2O2S:Tb - Gadolinium Sulfate:Tebrium Gd, TbY2SiO12:Ce - Yitrium Silicate: Cerium Ce Monzanite, OrthitePrinted Circuit Boards, Computer Chips

Silicon Si Quartz


Au - Gold Au AuAg - Silver Ag Ag, Pyrargyrite, CerargyriteTin Sn Cassiterite,Al - Aluminum Al Bauxite

There are 66 individual minerals that contribute to the typical computer that are identified above. There are others in addition to those above, but it should be evident that without many minerals, there would be no computers, or televisions, for that matter.

Mining TerminologyMining TerminologyOpen Pit Mine Open Pit Mine ––Bench Mining, Strip Mine or Bench Mining, Strip Mine or QuaryQuary

Overburden, Ore and Waste need to be MinedOverburden, Ore and Waste need to be Mined

Underground Mine Underground Mine –– Bulk or Selective.Bulk or Selective.Significantly less waste needs to be excavated.Significantly less waste needs to be excavated.More expensive/challengingMore expensive/challengingNumerous mining methodsNumerous mining methods

Hard Rock Hard Rock -- Requires Drilling and Blasting.Requires Drilling and Blasting.Soft Rock Soft Rock –– Use of continuous mining machines or free dig.Use of continuous mining machines or free dig.

In 2002 there were 365 underground mines in the Western worldIn 2002 there were 365 underground mines in the Western world11..In 2002 around 4,100 Mt of ore was mined of which 615 Mt In 2002 around 4,100 Mt of ore was mined of which 615 Mt (16%)was mined via underground(16%)was mined via underground11..

Mining Terminology Mining Terminology Mineral:Mineral: Inorganic substance that are extracted from the Inorganic substance that are extracted from the earth for use by man.earth for use by man.

Ore :Ore : Rock that contains a mineral or minerals in sufficient Rock that contains a mineral or minerals in sufficient quantities as to make commercial extraction (mining quantities as to make commercial extraction (mining ––milling) profitable.milling) profitable.

Grade :Grade : A measure of a mineral contained rock (or ore). Gold A measure of a mineral contained rock (or ore). Gold and other precious metals and other precious metals –– g/tg/t or oz/t, base metals or oz/t, base metals ‐‐ %, rare %, rare earth elements earth elements –– ppmppm……

Cut off Grade :Cut off Grade : The minimum concentration or grade of The minimum concentration or grade of mineral that is required for rock to be considered ore.mineral that is required for rock to be considered ore.

Waste :Waste : Not Ore.Not Ore.

Ore Body:Ore Body: A mineralized deposit (resource) whose A mineralized deposit (resource) whose characteristics have been examined and found to be characteristics have been examined and found to be commercially viable. The extents of the ore body are commercially viable. The extents of the ore body are determined by the cutdetermined by the cut‐‐off grade.off grade.

Host Rock:Host Rock: The rock containing an ore deposit.The rock containing an ore deposit.

Mining Terminology Mining Terminology

Vein:Vein: A narrow zone, or belt, of mineralized rock. A narrow zone, or belt, of mineralized rock.

Seam:Seam: A horizontal or sub horizontal bed of A horizontal or sub horizontal bed of mineral, usually associated with coal.mineral, usually associated with coal.

Strike:Strike: The angle at which a vein, structure or The angle at which a vein, structure or rock is located with respect to North Line.rock is located with respect to North Line.

DipDip: : The angle at which a vein, structure or rock The angle at which a vein, structure or rock bed is inclined from the horizontal, measured at bed is inclined from the horizontal, measured at right angles to the strike. right angles to the strike.

Plunge:Plunge: The angle at which a vein, structure or The angle at which a vein, structure or rock bed is inclined from the horizontal, measured rock bed is inclined from the horizontal, measured parallel to the strike. parallel to the strike.


HANGING WALLHANGING WALL: : An underground mining term describing the An underground mining term describing the interface between the interface between the orebodyorebody and the host rock, and the host rock, on the upper sideon the upper sideof the mining excavation (of the mining excavation (stopestope).).

FOOT WALLFOOT WALL : : An underground mining term to describe the An underground mining term to describe the interface between the interface between the orebodyorebody and the host rock , and the host rock , on the lower sideon the lower sideof the mining excavation (of the mining excavation (stopestope).).

Orebody

Hanging Wall (Host Rock)

Foot Wall (Host Rock)


DEVELOPMENT: DEVELOPMENT: Is the underground work carried out for the Is the underground work carried out for the purpose of reaching and opening up a mineral deposit. It includepurpose of reaching and opening up a mineral deposit. It includes shaft s shaft sinking, crosssinking, cross‐‐cutting, drifting and raising. cutting, drifting and raising.

SHAFT:SHAFT: A vertical or steeply inclined excavation used for moving workA vertical or steeply inclined excavation used for moving workers ers and materials, hoisting ore and waste, providing ventilation andand materials, hoisting ore and waste, providing ventilation and provides provides access for services such as compressed air, water, power and access for services such as compressed air, water, power and communications. communications.

Cage: Cage: ‐‐ The conveyance used to transport men and equipment in a The conveyance used to transport men and equipment in a shaft. shaft. Skip:Skip: A container used for hoisting material up a shaft.A container used for hoisting material up a shaft.Hoist: Hoist: ‐‐ The machine used for raising and lowering the cage or other The machine used for raising and lowering the cage or other conveyance in a shaft.conveyance in a shaft.Guides:Guides: The steel girders/ timber along the sides of a shaft for the The steel girders/ timber along the sides of a shaft for the purpose of steadying, or guiding, the cage or conveyance.purpose of steadying, or guiding, the cage or conveyance.Galloway:Galloway: Machine used for sinking (or excavating a Shaft)Machine used for sinking (or excavating a Shaft)Head frame:Head frame: Building that covers shaft and may also contain the hoist Building that covers shaft and may also contain the hoist room. room. Collar:Collar: The mouth or uppermost entrance to a shaft; also used to The mouth or uppermost entrance to a shaft; also used to describe the top of a drill hole.describe the top of a drill hole.Shaft Station: Shaft Station: Underground access point to a shaft, typically located at Underground access point to a shaft, typically located at the the ““Main LevelsMain Levels””..Loading Pocket: Loading Pocket: Location where ore is loaded into a skip for hoisting.Location where ore is loaded into a skip for hoisting.

Winze: Winze: A shaft collared (or started) below surface.A shaft collared (or started) below surface.

Open Pit

NVS Exhaust Fans

#2 Shaft

#1 Shaft

Portal

Surface InfrastructureSurface Infrastructure

Shaft Shaft –– Approach & EquipmentApproach & Equipment

Galloway @ 48L

Sheave Wheel InstallationSheave Wheel Installation

April 2003


Decline or Ramp:Decline or Ramp: A large inclined tunnel driven from the surface A large inclined tunnel driven from the surface to an underground ore body/coal seam. Provides access for men, to an underground ore body/coal seam. Provides access for men, equipment, material, ventilation and services. Typically drivenequipment, material, ventilation and services. Typically driven at a at a size and angle which allows mobile equipment access.size and angle which allows mobile equipment access.

AditAdit:: Horizontal tunnel driven into the side of a mountain to access Horizontal tunnel driven into the side of a mountain to access an an orebodyorebody..

Portal:Portal: The surface entrance to a Decline or The surface entrance to a Decline or AditAdit..

Drift Drift ‐‐ A horizontal underground passage or tunnel.A horizontal underground passage or tunnel.

Crosscut Crosscut ‐‐ A horizontal opening driven across the course of a vein A horizontal opening driven across the course of a vein or structure, or in general perpendicular to main access drifts.or structure, or in general perpendicular to main access drifts.

Draw point Draw point –– Access drift into the ore body from which ore is Access drift into the ore body from which ore is extracted or extracted or ““MuckedMucked””..

Shaft

Collar

Cross Cut

Raise:Raise: A vertical or subA vertical or sub‐‐vertical excavation, excavated from vertical excavation, excavated from the bottom up.the bottom up.

ManwayManway: : An access raise with a ladder installed.An access raise with a ladder installed.OrepassOrepass / Waste pass:/ Waste pass: Raise used to transport ore Raise used to transport ore or waste.or waste.Bin:Bin: Large diameter raise used to store ore or waste.Large diameter raise used to store ore or waste.

Chute:Chute: An inclined opening, usually constructed of concrete An inclined opening, usually constructed of concrete and steel and equipped with a gate, through which ore is and steel and equipped with a gate, through which ore is drawn from an drawn from an orepassorepass or bin.or bin.Ventilation Raise:Ventilation Raise: Intake (Intake (freashfreash air) and Exhaust (used air)air) and Exhaust (used air)

Mining TerminologyMining Terminology

Mining TerminologyMining Terminology

StopeStope ‐‐ An excavation in a mine from which ore is being or has An excavation in a mine from which ore is being or has been extracted. been extracted. Slot: Slot: The initial opening of a The initial opening of a stopestope..Backfill: Backfill: Material used to fill a Material used to fill a stopestope, once the ore has been , once the ore has been extracted. Waste rock, cemented waste rock, hydraulic fill and extracted. Waste rock, cemented waste rock, hydraulic fill and paste paste are example of back fill.are example of back fill.SublevelSublevel ‐‐ An intermediate level opened a short distance below the An intermediate level opened a short distance below the main level for drilling or for caving the ore body in the cavingmain level for drilling or for caving the ore body in the cavingsystem of mining.system of mining.FaceFace ‐‐ As applied to a drift, crosscut or As applied to a drift, crosscut or stopestope, is the end in which , is the end in which work is progressing. work is progressing. Undercut: Undercut: To remove the underlying ground. Also used to To remove the underlying ground. Also used to describe the lower level of a describe the lower level of a stopestope. Typically the mucking horizon.. Typically the mucking horizon.OvercutOvercut: : The upper level of a The upper level of a stopestope. Typically the drilling horizon.. Typically the drilling horizon.Powder:Powder: ExplosivesExplosivesCaps:Caps: DetonatorsDetonatorsSumpSump ‐‐ An excavation underground for the purpose of catching or An excavation underground for the purpose of catching or storing water; the bottom of a shaft is commonly used for this storing water; the bottom of a shaft is commonly used for this purpose. purpose.

NO. 5 ORE PASS

NO. 4 ORE PASS70L

75LNo. 4 NVR

No. 3 NVR

No. 4 Shaft

Ramp Down

Ramp Up

North “G” FaultSouth dipping ~ 85o

North “F” FaultSouth dipping ~ 85 o

Copper Stringer

Main LensWest Lens

South Lens

Greywacke Zone

LegendAndesite

Rhyolite

Talc – Carb

Greywacke

Primary Dev.

Pre-Prod. Dev.

Prod. Dev.

#1 Ore Pass

#5 Ore Pass

74 sublevelTypical Level Layout

StopeStope General General ArrangementArrangement

Chevron & Primary/Secondary Mining Chevron & Primary/Secondary Mining

2

378

11

2

8

Primary StopesSecondary Stopes

6

7

9

12

17

1 5

4 1011

1314

15

16STRIK

E

Production LHD Production LHD –– Toro 0011Toro 0011


Pillar : Pillar : Rock, typically ore, that is left in place to act as support.Rock, typically ore, that is left in place to act as support.Crown pillar Crown pillar : : A body of rock located above underground A body of rock located above underground operations that supports the surface above the underground operations that supports the surface above the underground openings (openings (stopesstopes) and aims to minimize subsidence.) and aims to minimize subsidence.Sill Pillar:Sill Pillar: A body of rock left in situ to separate between two A body of rock left in situ to separate between two levels or to support un cemented or low cement content backfill.levels or to support un cemented or low cement content backfill.Rib Pillar:Rib Pillar: A body of rock left in situ to separate and act as support A body of rock left in situ to separate and act as support between two between two stopesstopes or mine areas.or mine areas.

Shaft

Crown Pillar

Cross Cut

Mining TerminologyMining Terminology(Ground Support) (Ground Support)

ROCK BOLTINGROCK BOLTING ‐‐ The act of consolidating roof strata by The act of consolidating roof strata by means of anchoring and tensioning steel bolts in holes means of anchoring and tensioning steel bolts in holes especially drilled for the purpose.especially drilled for the purpose.

Rock bolts come in many types: Mechanical Bolts, Rebar, Rock bolts come in many types: Mechanical Bolts, Rebar, Split Sets, Split Sets, SwellexSwellex, Cable Bolts, Cont Bolts, Cable Bolts, Cont Bolts……

SHOTCRETE:SHOTCRETE: A type of ground control used in A type of ground control used in underground mines, where concrete, often with steel or underground mines, where concrete, often with steel or synthetic synthetic fibresfibres added for extra strength, is sprayed at added for extra strength, is sprayed at high pressure on to the walls of an opening to prevent high pressure on to the walls of an opening to prevent rocks from falling.rocks from falling.

TAILINGSTAILINGS ‐‐Material rejected from a mill after the Material rejected from a mill after the recoverable valuable minerals have been extracted. recoverable valuable minerals have been extracted.

Shot Crete SprayerShot Crete Sprayer

Ground SupportGround Support

Introduction to Introduction to Mining and Mining and Terminology Terminology

Resource and Resource and Reserve EstimationReserve Estimation

Ore dilution and its Ore dilution and its effectseffects

Introduction to Underground MiningIntroduction to Underground Mining

Resource and Reserve EstimationResource and Reserve Estimation

Ore:Ore: A A mineralisedmineralised deposit whose characteristics have been deposit whose characteristics have been examined and found to be examined and found to be commercially viable. commercially viable. The extents The extents of the ore body are determined by the cutof the ore body are determined by the cut‐‐off grade.off grade.Mineral Resource:Mineral Resource:


Mineral Reserve:Mineral Reserve:


Qualified Person (QP):Qualified Person (QP):

Resource and Reserve EstimationResource and Reserve EstimationTonnage Estimation of OreTonnage Estimation of Ore

The ultimate objective of all exploration is to predict, with thThe ultimate objective of all exploration is to predict, with the e greatest accuracy possible, the shape, distribution, and greatest accuracy possible, the shape, distribution, and concentration of mineralization.concentration of mineralization.

Create a geologic model to look at the three dimensional Create a geologic model to look at the three dimensional perspective of an mineralization deposit .perspective of an mineralization deposit . Purpose of ore deposit Purpose of ore deposit modeling is to predict the geology modeling is to predict the geology

Use this three dimensional model to calculate the quantity and Use this three dimensional model to calculate the quantity and quality of the ore deposit.quality of the ore deposit.

The information is examined along both horizontal slices (plan The information is examined along both horizontal slices (plan maps) and vertical cross sections (drill sections).maps) and vertical cross sections (drill sections).

Resource and Reserve EstimationResource and Reserve EstimationTonnage Estimation of OreTonnage Estimation of Ore

Based on a large amount of information (drill data, chip samplesBased on a large amount of information (drill data, chip samples, bulk , bulk samples, geophysical)samples, geophysical)

Drill holes are generally placed along a parallel drill lines, tDrill holes are generally placed along a parallel drill lines, to make the o make the calculation of the volume easier.calculation of the volume easier. A square grid is convenient, but not A square grid is convenient, but not essential.essential.

Increased confidence is achieved by more drilling followed by Increased confidence is achieved by more drilling followed by trenching at the surface or drifting underground and bulk samplitrenching at the surface or drifting underground and bulk sampling (test ng (test stopesstopes).).

Tonnage and grade calculations are done using Tonnage and grade calculations are done using geostatisticalgeostatistical methods methods using 3D geometries,3D block models and specialized software using 3D geometries,3D block models and specialized software ((DatamineDatamine, Vulcan, , Vulcan, SurpacSurpac, , MedSystemMedSystem etc.).etc.).

After the volume calculation is complete, the volume is converteAfter the volume calculation is complete, the volume is converted to d to weight by multiplying the volume by the weight by multiplying the volume by the ““tonnage factortonnage factor””.. The tonnage The tonnage factor states the density of the ore and host rock, in terms of factor states the density of the ore and host rock, in terms of cubic cubic feet/ton or cubic meters/feet/ton or cubic meters/tonnetonne..

Volume Estimation of Volume Estimation of Mineralization Mineralization

A)A) Drill intercepts interpreted to represent large, laterally Drill intercepts interpreted to represent large, laterally continuous ore bodies.continuous ore bodies. B)B) Same drill intercepts interpreted to Same drill intercepts interpreted to represent discontinuous, small scale ore bodies represent discontinuous, small scale ore bodies

Diamond DrillingDiamond Drilling

Block ModelBlock Model

Cross Section Showing Drill hole and Block Model –Grade and Tonnage Estimate

Mining Dilution and Recovery Mining Dilution and Recovery

Dilution is defined as material that is mined in the Dilution is defined as material that is mined in the process of ore extraction. Typically a process of ore extraction. Typically a contamination of ore with below cut off grade contamination of ore with below cut off grade material or with barren waste wall rock. material or with barren waste wall rock. Recovery is defined as the percent of valuable Recovery is defined as the percent of valuable material or ore that is extracted relative to the total material or ore that is extracted relative to the total amount of Ore.amount of Ore.Why does it occurs?Why does it occurs?Primary dilution and recovery (Planned) Primary dilution and recovery (Planned) Secondary dilution and recovery (Unplanned) Secondary dilution and recovery (Unplanned)

Mining Dilution Mining Dilution Why does it occurs?Why does it occurs?

Narrow or varying Ore Body widths;Narrow or varying Ore Body widths;Structures in the Hanging Wall;Structures in the Hanging Wall;Poor mining practices (blasting, bore hole)Poor mining practices (blasting, bore hole)Poorly understood Ore Body. Not enough drill information Poorly understood Ore Body. Not enough drill information ((““nuggetnugget”” Ore Body)Ore Body)

Primary dilution Primary dilution ‐‐ Planned DilutionPlanned Dilution‐‐ minimum mining width minimum mining width required to extract. 2 m ore width and 4 m wide drifts.required to extract. 2 m ore width and 4 m wide drifts.Secondary dilution Secondary dilution ‐‐ Unplanned Dilution Unplanned Dilution –– OverbreakOverbreak (too much (too much extracted) or extracted) or UnderbreakUnderbreak (less extraction). Failure in the (less extraction). Failure in the Hanging Wall due to poor ground conditions (rock bursting, Hanging Wall due to poor ground conditions (rock bursting, fault zones) fault zones)

Mining Dilution Mining Dilution -- Control Control Planned Dilution Control:Planned Dilution Control:

More data collected by diamond drilling, chip sampling, More data collected by diamond drilling, chip sampling, mapping, sampling of blast holesmapping, sampling of blast holesUse different mining equipment or appropriate mining Use different mining equipment or appropriate mining methods. Right size equipment for proper widths. methods. Right size equipment for proper widths.

Unplanned Dilution Control:Unplanned Dilution Control:More data collected by diamond drilling, chip sampling, More data collected by diamond drilling, chip sampling, mapping, sampling of blast holes;mapping, sampling of blast holes;Different blasting techniques;Different blasting techniques;Surveying of pre and post Surveying of pre and post stopestope blasting;blasting;Support Hanging Wall, backfill open Support Hanging Wall, backfill open stopesstopes

Unplanned Dilution After Blasted:Unplanned Dilution After Blasted:Grade control procedures Grade control procedures –– sort waste and ore (difficult)sort waste and ore (difficult)Move waste to empty Move waste to empty stopesstopes or bring to surface, secondary or bring to surface, secondary blast large waste rocksblast large waste rocksMine the waste and lower the grade leaving the mineMine the waste and lower the grade leaving the mine


Discounted Cash FlowDiscounted Cash FlowNPV (net present value) is a means of comparing a NPV (net present value) is a means of comparing a dollar today to the value of the same dollar in the dollar today to the value of the same dollar in the future. For mining projects, we apply NPV to future. For mining projects, we apply NPV to determine if a project is worth more than it costs.determine if a project is worth more than it costs.Free Cash Flow is the operating cash flow minus Free Cash Flow is the operating cash flow minus capital includes Taxes, Dividends, Royalties, capital includes Taxes, Dividends, Royalties, Depreciation and Amortization. I.e. the amount of Depreciation and Amortization. I.e. the amount of money left after the bills are paidmoney left after the bills are paidDiscount Rate is rate that future cash flows are Discount Rate is rate that future cash flows are discounted to determine present value. This is discounted to determine present value. This is different than interest. different than interest. IRR (internal rate of return) is the discount rate that IRR (internal rate of return) is the discount rate that results in an NPV of 0.results in an NPV of 0.


Value = Free Cash Flow

Rate = Discount Rate

n=Total number of periods

i=Period

Mine XYZDiscount Rate = 10%

Value of Uranium ($/lb) 50

Annual Production t/year 100000

Average Grade 3.5%

Operating Cost ($/lb) 30

Capital Cost ($000,000) 500

Construction Period (years) 3

Mine Life (years) 5

Capital - Operating Overlap (years) 1

1 2 3 4 5 6 7 Total

Capital Cost $166.7 $166.7 $166.7 $500.0

Operating Cost $231.0 $231.0 $231.0 $231.0 $231.0 $1,155.0

Revenue $385.0 $385.0 $385.0 $385.0 $385.0 $1,925.0

Free Cash Flow -$166.7 -$166.7 -$12.7 $154.0 $154.0 $154.0 $154.0 $270.0

Discounted Cash Flow -$151.5 -$137.7 -$9.5 $105.2 $95.6 $86.9 $79.0 $68.0

NPV $67.99

IRR 16.05%

Mining InformationMining Information

Infomine/EdumineInfomine/EdumineSaskmining.caSaskmining.caIR.GOV.SK.CAIR.GOV.SK.CACIM.orgCIM.orgSMESMENorthern minerNorthern minerKITCOKITCO

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