Lol 68g27

ROSEMONT: LOM MINE PLAN RP16JUN

| June 28, 2016

HBM

General Layout IMC - DFS

Plant

PIT

DSTF

SR 83

Ore stock WRF

INVESTOR PRESENTATION | 2

General Layout HB - RP16JUN

Plant

PIT

DSTF

SR 83

Ore stock WRF

INVESTOR PRESENTATION | 3

Mineral Resources Model

2015 (*)

2016 V1 (**)

2016 V2 (**)

2016 V3 (**)

M+I (M Tons)

1,018

1,279

1,319

1,294

Tcu%

0.39

0.35

0.35

0.35

SCu%

0.33

0.29

0.29

0.30

Cu Cont.

336

371

383

388

Inferred

129

167

121

84

1,147

1,446

1,440

1,378

Total

2015

2016

Notes • • •

NSR Cutoff for report o Oxide: 4.0 $ o Sulphur: 5.7 $ Main changes between models (*) 302 DH’s (**) 356 DH’s Model V3 is being used for detail mine plan RP16JUN.

(*) Pitshell IMC “new pit1.1.msr” (**) Pitshell Hudbay “pit3”

INVESTOR PRESENTATION | 4

Mineral Reserves Hudbay RP16JUN

IMC DFS 82,90 – 105,149

Pre – Stripping, Mt

105

105

Annual Movement, Mt

132

149

82 (1yr – 5 yr) 90 (6 yr – EOM)

82 (1yr – 5 yr) 90 (6 yr – EOM)

592

501

T Cu%

0.45

0.49

S Cu%

0.40

0.44

Waste, M tons

1,248

1,369

Stripping Ratio (SR)

2.1

2.7

Total Mined, M ton

1,840

1,870

76

48

1,916

1,918

20

17.5

2,080

1,929

Total: 641 Avg.: 128

Total: 674 Avg.: 135

Total: 1,440 Avg.: 103

Total: 1,256 Avg.: 114

Throughput, Ktpd Mill Ore, M ton

Rehandle, M ton Total Movement, M ton Life of Mine* Fine Copper, K Ton Fine Copper 1 – 5Yr, K ton Fine Copper 6 – EOM, K ton

Notes • *Life of Mine considers 1 yr of pre-strip period in RP16JUN mine plan in comparison with 1.5 yrs of IMC DFS. • Fine copper no affected by payable factors. • Recoveries for fines calculation are: 88% for Sulphur and mixed ores, and 81% for oxide ore. INVESTOR PRESENTATION | 5

Plan Optimized Until June 24, 2016 •

RESOURCES

o

•

New model 2016 V3 (June 08): o

Updated geological interpretation (litho and mineralization)

o

Updated geostatistical parameter of estimation

o

More tonnage but lower grade

RESERVES o

New model, more ore but less tonnage

o

Pit optimization with more revenue

o

Phases optimization (economical, technical operational): 6 phases, previous was 8 phases

o

Pit Schedule optimization: o

MSSO to mine better values in the earlier periods, two haul roads, equipment utilization. Experience from Constancia using in the KPI’s parameters.

o

•

o

132 Mton based on an NPV optimization.

o

Stripping ratio optimization

Geotechnical and Hydrogeological optimization using information from C&N, Neirbo, Dave Lewis and HB. Further geotechnical analysis: o

To updated database from holes, mapping, laboratory

o

Geotechnical model for RQD, hardness

o

Geotechnical sectors with lithology, geological faults, strength properties. IRA, Overall, pit design and pit mined worked together.

o

Slope stability sections and analyses

o

Hydrogeological analyses based on the hydrogeological review.

Mine CAPEX o

Mine Fleet Equipment with one less shovel.

INVESTOR PRESENTATION | 6

Path forward Before July 18, 2016 •

CAPEX

o

Pre-Stripping stage developed in 01 year. Direct & indirect cost savings.

o

Mine Equipment Purchasing (max asset utilization), cost savings around ~35 M $.

•

OPEX

DFS

RP16JUN

MINE OPERATIONS, M $

387.0

352

G&A

19.9

19.9

Operational Readiness

4.0

4.0

Mine Fleet Procurement

236.5

201.5

o

To reduce total OPEX cost (US$) per year (less material movement).

Pre-stripping

105.9

105.9

o

To reduce mine trucks, then OPEX reduction.

20.6

20.6

o

To optimize fleet equipment utilization (considering one less shovel)

Misc Items, Services & Light Vehicles

o

To review and optimize Drilling and Blasting

o

Fleet Management System to increase final asset utilization.

o

OPEX optimization from 1.23 $/t to 1.18 $/t (inc mine G&A). 5% reduction in total Opex

DFS

RP16JU N

Mining Infrastructure

5.7

5.7

Process Plant Dry Tailings Stacking System Subtotal Direct Costs

122.2

122.2

19.8

19.8

147.7

147.7

Indirect Cost

32.5

32.5

Owner’s costs

195.4

177.4

0

0

375.6

357.6

Description Direct Cost

•

SUSEX o

Mine Fleet Equipment (Trucks): DFS maximum 43 in year 6 to RP16Jun maximum 38 units in year. (~18 M$)

o

Dry Stacking Tailings Facility (DSTF) design and stacking plan review and

optimization (less total waste tonnage placed and in deferring periods). o

WRF design and loading plan (to optimize distance and according to DSTF plan and design).

Contingency

TOTAL COST

INVESTOR PRESENTATION | 7

Path forward Before July 18, 2016 IMC DFS Category

Type

Drilling

Loading Haulage

Equipment

Model

RP16JUN

Unit Price

Units

Blast-hole Drills

Atlas Copco PV271

$ 2,797,000

3

$

8,391,000

2

$

5,594,000

Blast-hole Drill, 7 7/8 - 9 7/8

Atlas Copco DML

$ 1,400,000

1

$

1,400,000

1

$

1,400,000

Electric Rope Shovel

Caterpillar 7495HD

$22,856,173

3

$ 68,568,520

2

$ 45,712,347

Hydraulic Shovel

Caterpillar 6060 FS

$10,500,000

1

$ 10,500,000

1

$ 10,500,000

Front End Loader

Caterpillar 994H

$ 5,726,500

1

$

5,726,500

1

$

Off Highway Mining Truck

Caterpillar 793F

$ 3,976,500

27

$107,365,500

25

Track Dozer

Caterpillar D10T2

$ 1,489,127

5

$

Front End Loader, 8 Yd.

Caterpillar 988H

$

918,516

1

Rubber Tired Dozer (RTD)

Caterpillar 834K

$ 1,211,555

3

Motor Grader

Caterpillar 16M

$

628,210

3

Water Truck 20000 Gallon

Caterpillar 777

$ 1,893,202

Hydraulic Excavator

Caterpillar 352FL w/Hammer CL

$

699,977

Loader Backhoe

Caterpillar 2 CY

$

All Terrain Crane Lube Truck Truck Mounted Lube Truck

Sub total

Units

Sub total

5,726,500

$ 99,412,500

7,445,635

4

$

$

918,516

1

$

918,516

$

3,634,665

3

$

3,634,665

$

1,884,630

3

$

1,884,630

4

$

7,572,808

4

$

7,572,808

1

$

699,977

1

$

699,977

180,500

1

$

180,500

1

$

180,500

TBD 75 Ton

$ 1,000,000

1

$

1,000,000

1

$

1,000,000

Caterpillar 773G

$ 1,365,058

2

$

2,730,116

2

$

2,730,116

TBD

$

213,400

1

$

213,400

1

$

213,400

Mechanic Field Service Truck Ford F550

$

282,075

6

$

1,692,450

6

$

1,692,450

Boom Truck

15 Ton

$

230,200

2

$

460,400

2

$

460,400

Forklift, Truck Shop

GRADE ALL 20,000 lbs

$

457,628

1

$

457,628

1

$

457,628

Integrated Tool Carrier

Komatsu 140HP/WA250

$

210,057

1

$

210,057

1

$

210,057

Solar Light Plant

Atlas Copco TBD

$

20,450

15

$

306,750

15

$

306,750

Cable Reeler

Caterpillar 980

$

840,900

1

$

840,900

1

$

840,900

Compactor

Caterpillar CS78LT

$

235,040

1

$

235,040

1

$

235,040

Shovel Motivator

TBD

$ 1,520,000

1

$

1,520,000

1

$

1,520,000

Spare Shovel Bucket

TBD

$ 2,250,000

1

$

2,250,000

1

$

2,250,000

Spare Truck Bed

TBD

$

1

$

300,000

1

$

300,000

$236,531,492

83

TOTAL MINE MOBILE EQUIPMENT

300,000

89

5,956,508

$201,409,692

Deferred equipment to SUSEX Cost (since year 02). INVESTOR PRESENTATION | 8

Preliminary Economic Analysis Impact

Operative analyses

Economic Model V3 (Mark G.)

Hudbay RP16JUN

IMC DFS 82,90 – 105,149

Hudbay RP16JUN*

IMC DFS 82,90 – 105,149

NPV @8%, USD M

1,403

1,188**

732

610

IRR, %

18.8%

16.4%

16.5%

15.8%

1.74

1.55

7

8

CAPEX*, USD M

1,895

1,895

1,860

1,895

OPEX*, USD M

5,569

5,046

5,900

5,466

SUSEX*, USD M

375

375

357

375

Operative Cash cost ($/Cu Lb)

1.37

1.34

1.50

1.54

Profitability Index Payback (yrs)

Notes • NPV, IRR, PI and Cash cost calculated by Technical Services Team for comparison purpose; It does not consider Silver Wheaton Stream and other economic and financial considerations. • * CAPEX and SUSEX cost estimation from DFS (Financial model V3 from Mark Gupta). • * OPEX defined by the following unitary costs for both mine plans:  Mine 1.14 $/ton - Mill 5.0 $/ton and G&A cost 1.0 $/ton • General cost revision for optimization and NPV improvement. • ** IMC NPV is affected by Silver Wheaton stream, which is US$ ~150 M. INVESTOR PRESENTATION | 9

Path forward After July 18, 2016 •

•

•

CAPEX

o

Geo-metallurgical study

o

Dry Stacking Tailing Facility, engineering update.

OPEX o

To reduce total OPEX cost (US$) per year

o

Review new alternatives of optimization for mine activities. Electric Drill alternative.

o

Blasting assessment, rock type evaluation.

o

To review and optimize Drilling and Blasting (Mine to Mill, Mine to DSTF, Mine to WRF)

o

Fleet Management System

o

Mine Maintenance Management (Strategy, major repair, overhauls, minor repairs)

SUSEX

o

•

o

DSTF design and loading plan o

KP design could be very conservative.

o

We need to review with more details the restrictions.

o

Mix, waste with tailings alternative

o

Mine Fleet Equipment (Trucks) as a consequence of the DSTF

o

Dry Stacking Tailings Facility (DSTF) design and stacking plan review and optimization

o

WRF design and loading plan (to optimize distance and according to DSTF plan and design).

NI 43 101, Rosemont 2016 INVESTOR PRESENTATION | 10

Path forward Project Country Production Metal Transport Method Filter % Solids (Sc) Clasificación % Fines Specify Gravity (SG) Moisture content % Density Compactation Annual Precipitation Annual Evaporation Lift width Gradient

Un Mantos Verde La Coipa El Peñon Cerro Lindo KARARA Rosemont KP 2016

ktpd

% SUCS %

mm mm

Chile 12 Cu Conveyor Bands 82-83 SM 35-40 2.67-2.69

Chile Chile 18 2.6 Cu Au trucks trucks Bands Bands 79-82 82-83 ML ML 53-55 61-65 2.76-2.78 2.60-2.62

no <50 >2,000

no <50 >2,000

no <50 >2,000

<10

<10

<10

Designer

Australia 35 Fe Conveyor Press 84-85

USA 90 Cu-Mo-Ag Conveyor Press 84-85

USA 90 Cu-Mo-Ag Conveyor Press 84-85

>4.0 18

2.95 - 3.05 12.0 - 18.0 1.84 no 400 1,810 20m <10

2.95 - 3.05 12.0 - 18.0 1.84 no 400 1,810 20m <10

310 3,875 25m <10

Only Start Up Downstream (yr10) No Dam Dam Upstream (LOM)

Dam configuration Overall angle Total Height Seismic Factor

Perú 15 Zn-Pb-Cu trucks Bands 87-88 ML 56-58 4.0-4.2 6.0 - 8.0 2.7-2.8 si 200 1,500 0.3 m >20

2.8:1 g

>0.45

>0.30

>0.45

Rosemont Tetra Tech - Amec 2013

Upstream

0.45

3.0:1 90 <0.30

3.5:1 180 0.33

3.5:1 180 0.33

Golder

SRK

KP

Tetra Tech Amec

INVESTOR PRESENTATION | 11

Strategic Alternatives: Ridge Line & Process Plant

| June 28, 2016

HBM

RP16JUN Strategic: Cases to optimization Since year 06 must choose the strategy to follow the Ph06

Preliminary Pit Shell Constraint Cases Type Whittle Factor Cu Price, $/lb Impact? Process Plant Offset, ft Ore Mst TCu % SCu % NSR $/t Waste Mst Total Mst SR Additional life of mine (yrs)

RL 43 Ridge Line Base Case A 0.80 1.00 3.15 4.10 NO YES 400 592 764 0.45 0.42 0.40 0.37 20.6 19.1 1,249 1,844 1,841 2,608 2.11 2.41 5

Plan view NoRL 35 NoRL 42 without Ridge Line B C 0.90 1.00 3.15 3.80 NO YES 400 841 1,006 0.42 0.39 0.37 0.35 18.9 18.0 1,720 2,390 2,561 3,395 2.05 2.38 8 13

G

Case C Case B Case A

Process Plant

Ph06

Elevation DSTF WRF Overall slope DSTF WRF

Mst Mst Mst

ft ft H/V H/V

1,121 720 1,841

1,341 1,220 2,561

Current constraints

No constraints

5,490 5,700

5,800 5,800

3.5:1 3.0:1

3.5:1 3.0:1

Case B Case C Case A

STOCK & WRF

G´

Section view GG´ Stock & WRF

Ridge Line

Storage Capacity DSTF WRF Total

320ft

Base Case

B

C

A

INVESTOR PRESENTATION | 13