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Tarkwa Gold MineTechnical Short Form Report31 December 2012

1. OverviewGold Fields Ghana Limited (GFGL) was incorporated in Ghana in

1993 as the legal entity holding the Tarkwa concession mining

rights. Gold Fields Ghana Holdings Limited holds 90% of the

issued shares of GFGL, after acquiring the indirect 18.9% of the

issued shares belonging to IAMGold and its affiliates. The

government of Ghana holds a 10% free carried interest, as

required under the mining law of Ghana. The Tarkwa Gold Mine

operates under seven mining leases covering a total area of

approximately 20,825 hectares.

The Tarkwa Gold Mine is located in south-western Ghana near

the southern end of what is commonly referred to as the Tarkwa

Basin and is 300 kilometres by road west of Accra, the Ghanaian

capital. The mine is easily accessible with an established

infrastructure.

The open pit surface operation exploits narrow, tabular auriferous

conglomerates similar to those mined in the Witwatersrand Basin

of South Africa. Mining is currently taking place from four pits –

Pepe-Mantraim, Teberebie, Akontansi and Kottraverchy. At

present the mine uses a conventional Carbon-In-Leach (CIL) plant

and a Heap Leach facility. In the 12 months ended December

2012, Tarkwa produced 719 koz of gold from the milling and heap

leach operations at a cash cost of US$673/oz.

The extended LoM is primarily due to the inclusion of the South

Heap retreatment through the CIL plant at the end of life. The

North Heap facility will continue until it becomes uneconomical,

which is currently estimated to be 2014/5. Various alternative

processing options are currently being investigated, including an

expansion of the existing CIL plant and/or the construction of an

applicable, discrete CIL/CIP facility. Alternatively the mine will

revert to the CIL option only, which currently produces the best

cash returns in the medium term and extends the Life of Mine

(LoM) to 2036.

This Technical Short Form Report reflects the latest LoM plan input

parameters, coupled with an updated Mineral Resource and

Mineral Reserve statement, as at 31 December 2012.

All Mineral Resource and Mineral Reserve figures reported are

managed unless otherwise stated, and Mineral Resources

are inclusive of Mineral Reserves.

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Geographic locationTarkwa locality plan with mining lease magnified

1Gold Fields – Tarkwa Gold Mine – Technical Short Form Report 2012 �

Page head

Geographic location IFC

1. Overview IFC

2. Asset fundamentals Page 2

3. Operating statistics

4. Geological setting and mineralisation Page 4

5. Mining Page 6

6. Projects Page 7

7. Mineral processing Page 8

8. Sustainable development Page 9

9. Mineral Resources and Mineral Reserves Page 10

10. Competent Persons Page 13

11. Key technical staff Page 14

12. Brief history Page 17

Cover image: Mining operations at Teberebie

Note: For abbreviations refer to page 27 and for glossary of

terms refer to page 28 – “Mineral Resources and Mineral

Reserves Overview 2012”.

��Aerial view of sustainable rehabilitation programme at Tarkwa

Contents

gold d osits and is a remier

West Africa is host to world-class West Africa is host to world-class

gold deposits and is a premier gold deposits and is a premier

mining destination. Gold Fieldsmining destination. Gold Fields

has a strong presence in the regio has a strong presence in the region has a strong presence in the region

and Tarkwa is ideally positioned to and Tarkwa is ideally positioned to and Tarkwa is ideally positioned to

support the Gold Fields vision: support the Gold Fields vision: support the Gold Fields vision:

“To be the global leader in “To be the global leader in

i bl ld i i ”sustainable gold mining.”sustainable gold mining.”

2 � Gold Fields – Tarkwa Gold Mine – Technical Short Form Report 2012

2. Asset fundamentals

Prepared by Gold Fields Limited in compliance with the South African Code for the Reporting of Exploration

Results, Mineral Resources and Mineral Reserves (2007 SAMREC Code)

Effective date 31 December 2012

Source of information This Technical Statement is a summary of the December 2012 Tarkwa Competent Persons Report

(CPR)

Personal inspection Personal inspection is conducted by the Competent Persons as listed, who are full-time

employees of Gold Fields Limited

Independent review Information reported in this declaration is as reviewed by internal consultants as at 31 December

2012. Tarkwa has been informed that the review identified no material shortcomings in any

process by which the Mineral Resources and Mineral Reserves were evaluated

General location Tarkwa is located in south-western Ghana approximately 300 kilometres by road west of Accra,

the capital, at latitude 5° 15’ N and longitude 2° 00’ W. The Tarkwa Gold Mine is located four

kilometres west of the town of Tarkwa with good access roads and an established infrastructure.

The mine is served by a main road connecting to the port of Takoradi some 60 kilometres to the

south on the Atlantic coast

Climate Although there may be minor disruptions to operations during the wet season, there are no

long-term constraints on production due to climate

Licence status and

holdings

The Tarkwa mine operates under mining leases covering a total area of approximately

20,825 hectares. Five mining leases, dated 18 April 1997, cover the Tarkwa property, while two

mining leases, dated 2 February 1988 and 18 June 1992 respectively, cover the Teberebie

property. The Tarkwa concession mining leases expire in 2027 and the Teberebie property mining

leases expire in 2018. Application for an extension of the mining leases will be applied for at the

appropriate time, but there is no reason to expect that these will not be granted. All necessary

statutory mining authorisations and permits are in place for the Tarkwa Mine Lease and GFGL is

entitled to mine all material falling within the lease

Operational

infrastructure

The existing surface operation currently exploits narrow auriferous conglomerates, similar to those

mined in the Witwatersrand Basin of South Africa. Following a feasibility study in 2004, the deposit

is mined on an owner-operated basis, and processing from 2004 to December 2012 utilised a

conventional CIL plant as well as a heap leach facility

Deposit type The open pit surface operation currently exploits the tabular auriferous conglomerates from four

open pits – Pepe-Mantraim, Teberebie, Akontansi and Kottraverchy

Life of Mine (LoM) It is estimated that the current Mineral Reserves will be depleted in 2036 (24 years)

Environmental/Health

and Safety

Tarkwa retained its ISO 14001:2004 environmental management system and certification following

an external audit during 2012. The mine also retained its full compliance to the International

Cyanide Management Institute (ICMI) Cyanide Management code

Reporting codes Gold Fields reports its Mineral Resources and Mineral Reserves in accordance with the 2007

SAMREC Code, the South African Codes for the Reporting of Mineral Asset Valuation (2009

SAMVAL Code) and other relevant international codes such as the United States Securities and

Exchange Commission (SEC) Industry Guide 7, the Joint Ore Reserves Committee (JORC 2012)

Code and the National Instrument (NI) 43-101. The Mineral Resources and Mineral Reserves are

underpinned by an appropriate Mineral Resource management process and protocol to ensure

adequate corporate governance in respect of the Sarbanes-Oxley Act

Transporting ore In pit fuel farm Water treatment plant Aerial view of metallurgical plant


3. Operating statistics

Historic performance Units

Dec

2012

Dec2011

Dec20101

June2010

June2009

Open pit mining

Total mined kt 138,238 117,156 67,063 134,131 132,585

– Waste mined kt 116,330 94,927 56,008 111,051 109,906

– Ore mined kt 21,908 21,876 10,840 22,716 21,273

Mined grade g/t 1.3 1.2 1.2 1.2 1.2

Strip ratio (tonnes) waste:ore 5.3 4.4 5.2 5.2 5.1

Processing

Total tonnes kt 22,910 23,138 11,496 22,716 21,273

– Mill tonnes kt 11,600 11,426 5,639 11,182 7,733

– Heap leach tonnes kt 11,310 11,713 5,857 11,634 13,540

Combined head grade g/t 1.1 1.2 1.0 1.0 1.1

– Mill head grade (CIL) g/t 1.4 1.4 1.4 1.4 1.4

– Heap leach head grade g/t 0.8 0.9 0.9 0.9 0.9

Combined yield g/t 1.0 1.0 1.0 1.0 0.9

Plant recovery

factor

Mill % 97 97 97 97 97

Heap leach % 61 61 65 70 68

Gold produced

Total gold productionkoz 719 717 362 721 612

kg 22,358 22,312 11,261 22,415 19,048

– Mill koz 540 518 261 503 314

– Heap leach koz 179 199 101 218 299

Gold sold koz 719 717 362 721 612

Financials

Operating cost US$/oz 688 608 575 521 523

Total cash cost UUS$/oz 673 556 562 536 521

Capital expenditure US$ million 260 219 117 149 201

Notional cash expenditure (NCE) US$/oz 1,049 913 889 743 881

General

Total employees costed (TEC) number 4,175 4,024 4,153 4,377 4,107

Mineral Reserves Mt 293.3 264.8 235.3 244.2 270.0

Mineral Reserves Head Grade g/t 1.1 1.2 1.2 1.3 1.2

Mineral Reserves Moz 10.1 10.3 9.3 9.9 10.7

Expected Life of Mine years 242 13 12 12 13

1 Figures shown represent the six months to 31 December 2010.2 Extended due to the inclusion of retreatment of South Heap Leach at the end of the LoM.

Rounding off of figures presented in this report may result in minor computational discrepancies. Where this occurs it is not deemed significant.

Open pit mining operations


4. Geological setting and mineralisation

The Tarkwa ore bodies are located within the Tarkwaian

System, which forms a significant portion of the stratigraphy

of the Ashanti Belt in southwest Ghana. The Ashanti Belt is

a north-easterly striking, broadly synclinal structure made

up of Lower Proterozoic sediments and volcanics underlain

by the metavolcanics and metasediments of the Birimian

System. The contact between the Birimian and the

Tarkwaian is commonly marked by zones of intense

shearing and is host to a number of significant shear-hosted

gold deposits.

The Tarkwaian unconformably overlies the Birimian and is

characterised by lower intensity metamorphism and the

predominance of coarse-grained, immature sedimentary

units.

Local geologyThe local geology at Tarkwa is dominated by the Banket

Series, which can be further subdivided into a footwall and

hangingwall barren quartzite, separated by a sequence of

mineralised conglomerates and pebbly quartzites.

The stratigraphy of the individual quartzite units is well

established, with auriferous reefs interbedded with barren

immature quartzites. The units thicken to the west and

current sedimentological parameters indicate a flow from the

east and north-east. Structurally, the Tarkwaian belt has been

The Tarkwa operation exploits narrow auriferous conglomerates, similar to those mined in the Witwatersrand Basin of South Africa and currently mines from four open pits – Pepe-Mantraim, Teberebie, Akontansi and Kottraverchy.

subject to moderate folding, and at least five episodes of

deformation are recognised. The original deposition occurred

in a district basin environment with associated low to steep

angle normal faulting. Subsequent compression and folding

led to the development of thrust faults and inversion of

previous normal faults. The final stages involved further

thrusting in a southwest direction.

Sedimentological studies of the detailed stratigraphy within

individual A and A footwall reef units have led to the

recognition of both lateral and vertical

facies variations. The modelling of these

has resulted in the recognition of a

cycle of events from initial channel

formation and rapid down-cutting of the

central channel, through a period of

uplift and reworking. Finally, a period of

meandering channel bars and flow

reduction led to the development of

low-grade conglomerates with silty

interbeds. The period of uplift and

reworking has been recognised as

being the principal episode of gold

deposition and concentration within

these reefs. The style of sedimentation

in the C, E and G reefs differs from that

of the channelised, incised A reefs to a

more localised sheet-flood-dominated

alluvial fan deposit.

The mineralised and potentially

economic conglomerate reefs are

identified below; from the base upwards

(younging):

�� AFc – up to 3 metres thick, only

occurs in the west and subcrops

against the A1 in the east. Well

sorted with rounded clasts of

quartzite and visible gold;

Geology of south-western Ghana

Takoradi

Group Series Thickness (m) Lithology

Tarkwaian

(youngest) Huni 1,370

Quartzites, minor

phyllites

Tarkwa

Phyllite 120 – 400

Chloritic and sericitic

phyllites and schists

Banket 120 – 160

Quartzites, grits and

conglomerates

Major

unconformity � Kawere 250 – 700

Quartzites, grits and

conglomerates

Birimian (oldest) Birimian

Meta-volcanics,

volcaniclastics and

sediments


The current diamond drilling programme is guided by the

unconstrained Whittle® pit optimisations, which indicate the

potential for the economic extraction of pay shoots down-dip in

some parts of the current pits. The increase in resource gold

price to US$1,650/oz has resulted in an infill down dip diamond

drilling programme to increase resource definition. This will also

upgrade the Mineral Resource category ahead of mining and

provide detailed information for assessment of alternative select

mining cuts of the reef packages. Processing of the completed

boreholes is currently in progress.

�� A1 – between 2 and 7 metres thick,

moderately to poorly sorted

conglomerate and thin quartzites

with occasional visible gold;

�� A3 – up to seven metres thick,

moderately sorted thin

discontinuous conglomerate lenses

within a package of cross-stratified

quartzites, visible gold is rare;

�� B2 (or B) – up to three metres thick,

very coarse quartzites with thin lags

of subrounded pebble conglomerate

in the Akontansi Central area. In the

other areas it is poorly developed

and not economically extractable;

�� CDE – up to eight metres thick and

can be subdivided into the lower C

reef and upper E reef, both of which

are conglomeratic and are separated

by the D reef quartzite;

�� F2 – a variably developed polymictic gravel up to two

metres thick, essentially a marker horizon, except in the

east where it carries low grades; and

�� G – varies from a 2 to 6-metre thick poorly-sorted

conglomerate with clasts of quartzite and phyllite.

Exploration and resource definition drillingThe bulk of the Tarkwa open pit palaeoplacer Mineral Resource

has been drilled to the Measured and Indicated Mineral

Resource categories at current costs and a gold price of

US$1,650/oz. Tarkwa is now a mature mine with the focus

having shifted from exploration to optimising the extraction of

the current Mineral Resource.

Exploration drilling and expenditure:

31 December 2012 31 December 2011

Operation

Metres

drilled

US$

(million)

Metresdrilled

US$(million)

Tarkwa Gold Mine 13,529 3.720 5,588 0.448

Exclusive of grade control drilling except where it is included in the capital budget.

Stratigraphic profile of the Tarkwa ore body

Surface geology and infrastructure


The mine is owner-operated and has its own load and haul

fleet of 15 excavators, which range from 120 to 600 tonnes.

The haul fleet includes 51 dump trucks with a payload of

146 tonnes, eight dump trucks with a payload of 240 tonnes

and 17 dump trucks with a payload of 90 tonnes. The load

and haul fleet are supported by an ancillary fleet consisting of

dozers, graders, water carts and compactors. Twenty-four

owner-operated drill rigs are used for blast hole drilling.

Maintenance of the Caterpillar fleet is carried out by Gold

Fields Ghana Limited, while maintenance of the excavators

and blast hole rigs is carried out by contractors. In 2013,

Tarkwa plans to mine a total of 139 million tonnes of material

at a stripping ratio of 5.7:1.

Mining methodsTarkwa utilises a proven and highly selective mining

methodology. The location of the mining areas is defined

through the long-term planning process. The boundaries of

the pits are pegged out by survey and the area is cleared

of bush and topsoil, which is relocated for rehabilitation

purposes. After clearing, reverse circulation (RC) grade control

drilling is carried out, and geological models constructed. This

grade control information is used to update the short-term

plans and forecasts prior to the commencement of mining.

From the highest point in the pit, material is free dig or blasted

to the first blasting reference level. Currently fresh rock and

transitional zones are drilled and blasted in 6-metre lifts, with

excavation in 3-metre flitches.

Fifteen backhoe excavators are used to select waste from the

ore, and vice versa. This takes place along the sedimentary

horizons to an average accuracy of 30 centimetres on the

hangingwall, and 20 centimetres on the footwall of a reef. Pit

geologists and geotechnicians supervise all digging and

mineralised material is classified as either Run of Mine (RoM),

which is delivered to one of two primary crushers, or low

grade, which is stockpiled close to the primary crushers.

Waste material is hauled to the nearest waste dump.

Blasting currently utilises relatively close patterns and small

diameter holes, typically a 3.4-metre by 3.8-metre grid with

a hole diameter of 118 millimetres and a powder factor of

0.75 kg/BCM. Larger diameter holes and an increased grid

size will be utilised in the partially weathered material, while

decreased grid sizes will be utilised in harder material. The

small-diameter holes are used to preserve, as far as possible,

the integrity of the ore/waste contacts for selective mining

purposes.

Mine planning and schedulingIn general, all mine design and scheduling is undertaken

using Surpac®, Datamine®, Whittle®, Xeras®, Xpac® and

in-house computer software, together with the indirect

conditioning recoverable model (ICR). The planning cycle

commences with the ratification of key input parameters,

before producing a compliant Mineral Resource statement

that is adjusted for all Mineral Resource depletions. This is

followed by the planning process which includes a corporate

decision on macro-economic parameters, the development

of a one-year operational plan and the roll-out of the

operational plan into a LoM plan, which forms the basis of

Tarkwa’s annual Mineral Reserve declaration.

Standard software is utilised to derive the optimal pit shell

designs at a variety of cut-off grades. The detailed

engineering and design work on the optimised pit shells and

scheduling is carried out using these software packages.

A cut-off grade strategy is used in the Mineral Reserve

estimation process. The cut-off defines the ore/waste

segregation, and a cut-over grade defines mill/heap leach

segregation. A third cut-off known as the optimal cut-off/

cut-over is also derived and can be applied to increase

the grade and therefore the cash flow in the initial years of

the LoM plan. Material between the optimal cut-off/cut-over

and the process cut-off is stockpiled for treatment at the end

of the LoM.

5. Mining

Tarkwa is a large, established open pit gold mine that utilises selective surface mining

methods to optimise the extraction of the sedimentary mineral deposits.

Selective mining at Tarkwa


A detailed one-year operating and capital cost budget is

developed for all operational plans and, where appropriate,

extended for the LoM production schedule. Zero-based

costing is used to formulate the one-year plan. Historic

productivity data and operating costs are utilised as the basis

from which the operational budget is benchmarked. All

capital projects are ranked and prioritised to maximise capital

efficiency and return on investment.

The North Heap facility will continue until it becomes

uneconomical, as increased hardness and reduced porosity

negatively impacts the gold recovery. Various alternative

processing options are currently being investigated, including

an expansion of the existing CIL plant and/or the construction

of an applicable, discrete CIL/CIP facility. Alternatively the

mine will revert to the CIL option only, which will result in gold

recovery rates increasing from approximately 52%, for low

porosity material treated through Heap Leach, to 97%

through the CIL plant. The extended LoM is primarily due to

adopting a CIL option only and the inclusion of the South

Heap retreatment which will be treated through the CIL plant

at the end of life.

Mining operations at Teberebie

6. Projects

Tarkwa’s assets can be best optimised through organic

growth, increased efficiency and productivity. Business

improvement is therefore core to optimising the assets and

consequently Tarkwa embarked on the TEP6 feasibility study,

following the recommendations of the Tarkwa Options

Trade-Off Study (TOTOS), which focused on delivering a

high-value strategic direction for the mine. Among these

recommendations was the installation of a conventional

milling/leach circuit, to offset the impact of increasing

hardness and declining recoveries of the ore currently being

processed through the North Heap Leach facility. Further

work is currently in progress to determine the optimum

mining and processing capacities.

Other projects that were initiated in 2012 and are planned to

be evaluated in 2013, focus on:

�� evaluating alternative waste dumping and tailings disposal

strategies, including co-disposal;

�� improvement of heavy mining equipment infrastructure to

support the expanded LoM mining fleet;

�� a scoping study to reassess if there is a realistic

opportunity for ultimate economic extraction of the

underground Mineral Resources at the mine; and

�� review options to increase CIL capacity – mini TEP6

(~2 – 5 million tonnes)

Each of these initiatives is aimed at improving the profitability

of the operation.

In pit fuel farm to improve heavy mining equipment logistics

Recent reinterpretation work over the entire tenement holding has highlighted a number of

conceptually prospective target areas. Target definition and initial drilling activities started in

2012 are on hold for 2013.


Since 1999, all ore has been sourced from open pit mining

operations and is currently processed at the 9.8 Mtpa North

Heap Leach facility and the 12.3 Mtpa CIL plant. A third

facility, the South Heap Leach facility, was closed in

December 2008, but will be processed through the CIL plant

at the end of the LoM.

The ore is a free-milling conglomerate with negligible sulphide

content. Rocks near the surface have been affected by a high

degree of weathering which is associated with increased

porosity and increased heap leach dissolution and recovery.

The North Heap Leach facility was commissioned in 1998 to

process the initial highly porous ore and the construction of

the Phase V heap leach pad was completed in 2009. As the

mine gets deeper, so the percentage of weathered ore

amenable to heap leaching decreases. This justified the

construction of the CIL plant in 2004 and its subsequent

expansion, commissioned in January 2009. The CIL milling

process provides a 97% recovery which is not possible when

using heap leaching for the harder, unweathered ore, the

percentage of which increases over the LoM.

The North Heap Leach facility employs three stages of

crushing prior to agglomeration. Post primary crushing

through a gyratory crusher, a series of overland conveyors

transport the undersize material to the agglomeration

stockpile where it joins the final product. Secondary crushing

product is fed to the tertiary hopper via a series of conveyors.

The oversize material from the upper and lower decks

(32 mm and 22 mm respectively) feed the tertiary crushers

and the discharge from the tertiary crushers is conveyed

back to the tertiary bin. The undersize material from the

tertiary screens joins the final crushing product to the

agglomeration stockpile.

The agglomeration process involves the addition of 4 kg/t of

cement to the crushed rock to bind the fine material and

produce agglomerate that remains stacked and porous on the

heap leach pads. Following agglomeration, the ore is

transferred by conveyor and stacked on the leach pads by a

stacking conveyor.

The heaps are irrigated with a cyanide solution which dissolves

the gold as it percolates through the heaps. The pregnant

solution is collected on the layer of geotextile that lines the base

of the heaps and is pumped through a series of ponds to the

adsorption/desorption/recovery (ADR) plant. Here the gold is

adsorbed onto activated carbon, removed from the carbon by

acid wash, and recovered using electro-winning. All gold

produced at the North facility is smelted at the smelt house

using diesel-fired furnaces.

The CIL process route has a gyratory crusher that feeds two

crushed ore stockpiles, each with a live capacity of 45,000

tonnes (30 hours). Underneath each stockpile is a reclaim

tunnel, with apron feeders that feed onto a conveyor belt.

These in turn feed the milling circuit, which consists of a

semi-autogenous grinding (SAG) and ball mill. Recycle

crushing is in closed circuit with the SAG mill that has 14 MW

of installed power (2 x 7,000 kW twin-drive motors). The ball

mill has 14 MW of installed power (2 x 7,000 kW twin

drive-motors) and is in close circuit

with the cyclone cluster. The milling

circuit is operated at a capacity of

1,450 tph.

The CIL circuit consists of two trains of

eight tanks in series, which are fed from

a common leach tank. The loaded

carbon passes into a 15-tonne acid

wash column. The gold is recovered

from the loaded carbon in two 15-tonne

elution circuits. Gold is recovered from

solution by electro-winning and

smelted in an induction furnace at the

CIL smelt house.

The CIL expansion project will review the optimal tonnage profile for Tarkwa, taking into

account the fleet, ore availability, metallurgical response and required stripping ratio.

7. Mineral processing

CIL plant flow diagram

Crusher pocket

Crusher

CV01CV114 CV02 CV03

CV115

CV161

Eluted carbonscreen

2 x Regeneration kilns

2 x elutioncolumn Loaded carbon

screen

Acid column

CIL 2 tanks

CIL 1 tanks

Electrowinningcells

Pregnant solutiontank

Tailingsscreens

Furnace

Tailings tank

Tailings tank

Tailings 1 storage facility

Tailings 2 storage facility

Tailings screens

3 x ThickenerCarbon sizing

screens

Scats stockpile

4 x Trash screens

Mill returntank

Process waterpond

Milldischarge

screen

Cyclones

SAG mill

Ball mill

CV162

Stockpile

CV04

Auxiliarystockpile

CV116

LoM tailings storage facility assessment

Mining asset

LoM

deposition

(Mt)

Available

capacity

(Mt)

Surplus/

(shortfall)

Mt

Capital

requirement

US$ (million)

Tarkwa 286 297 11 290


8. Sustainable development8. Sustainable development8. Sustainable development

Tarkwa’s risk-based approach to safety management seeks to

control and, where possible, eliminate hazards in the working

environment. The mine strives to achieve and maintain an

outstanding health and safety performance through the

engaged participation of employees and the application of

safe, innovative processes and technologies – all within a

framework of OHSAS 18001 and full compliance.

Tarkwa’s health and safety management system has

undergone an annual comprehensive external compliance

audit since 2005 and certification has been retained to date.

The OHSAS 18001 system is aligned with Gold Fields

Limited’s Full Compliance Health and Safety Management

System, which acts as the Group standard for the

management of occupational health and safety. It aims to:

�� Eliminate all fatal accidents at all Gold Fields operations;

�� Reduce all accident rates by 50% over five years; and

�� Maintain a safe and healthy working environment at all

times through quality training, effective communication

and employee commitment.

The initiative has the broad support of all labour unions and

associations, individual employees and management. Tarkwa

operates a comprehensive employer HIV/Aids programme

comprising Informed Consent Voluntary Counselling and

Testing (ICVCT), disease prevention and health promotion

programmes. An HIV/Aids Co-ordinator is responsible for the

implementation of an HIV/Aids programme, with the full

co-operation of the employee representative bodies and

according to the international Labour Organisation and Gold

Fields Group standards. The programme incorporates

HIV/Aids awareness and training into the mine’s induction

programme for both employees and contractors. Peer

educators facilitate discussions on HIV/Aids during health and

safety meetings and provide formal counselling and training to

on-site and off-site communities. During 2011, Gold Fields

Ghana won the Global Business Coalition’s 2011 Business

Action on Health Award for Workforce/Workplace Engagement

– with a particular focus on HIV/Aids management.

Cyanide is managed under the framework of the ICMC and the

mine was certified ICMC-compliant in June 2008. The Code

requires compliance from all suppliers and transporters of

cyanide to ensure optimal safety and responsible use. The use

of cyanide on-site is strictly monitored and changes are

incorporated into operational procedures wherever necessary.

Environmental management at Tarkwa is conducted within

the framework of an ISO 14001:2004 certified environmental

management system. Tarkwa operations follow Ghanaian

environmental requirements, as administered by the

Environmental Permitting Agency (EPA), and hold the required

environmental permits. Tarkwa complies with the EPA

requirements and provides monthly monitoring returns, an

annual environmental report and an update of the

environmental management plan (EMP) at three-year

intervals. An Environmental Impact Study (EIS) was submitted

to the Ghana EPA in March 2007 for the Tarkwa expansion

project, and approved on 27 May 2007.

Tarkwa is currently awaiting its certificate from the EPA for the

period 2010 to 2013.

Blast hole drilling at Tarkwa

Safety statistics

Class Units Dec 2012 Dec 2011 Dec 2010* June 2010 June 2009

Fatalities number – 1.0 1.0 – –

Fatality rate per mmhrs – 0.10 0.10 – –

LDIFR2 per mmhrs 0.2 0.2 0.4 0.4 0.3

1For six months to December 20102Lost Day Injury Frequency Rate

Tarkwa retained its ISO 14001:2004 environmental management system and re-certification

following an external audit during 2012. The mine also retained its full compliance to the ICMI

Cyanide Management code.


9. Mineral Resources and Mineral Reserves

Stockpile tonnage and grade estimates are based on accumulations of estimated tonnage and grades trucked throughout the history of the mine, and are therefore considered to be reasonably accurate. However, the grades and tonnages are discounted by 5% for processing purposes as experience has shown that this is realistically achievable when reclaiming a stockpile. RoM stockpile tonnages were reconciled to survey volumes in December 2012. Unless otherwise stated, all Mineral Resources and Mineral Reserves are quoted as 100% and are not attributable with respect to ownership.

Mineral ResourcesMineral Resources are quoted at an appropriate in situ economic cut-off grade, with tonnages and grades based on the resource block model. They also include estimates of any material below the cut-off grade that is required to be mined in order to extract the complete pay portion of the Mineral Resource.

This declaration is based on the premise that the heap leach process at the North Heap Leach facility will be reassessed at the end of 2013 and the milling processing capacity to be reviewed and optimised.

Mineral Resource classification

Classification

Tonnes (Mt) Grade (g/t) Gold (koz)

Dec

2012

Dec 2011

Dec 2010

Dec

2012

Dec 2011

Dec 2010

Dec

2012

Dec 2011

Dec 2010

Open pit and underground

Measured 113.0 112.0 123.5 1.46 1.49 1.46 5,292 5,361 5,798

Indicated 142.0 167.5 125.1 1.24 1.24 1.29 5,665 6,694 5,186

Inferred 30.1 33.6 14.3 2.92 2.76 3.44 2,825 2,985 1,580

Total open pit and

underground 285.1 313.1 262.8 1.50 1.49 1.49 13,782 15,041 12,565

Heap leach re-treat and

stockpiles

Indicated (South Heap Leach) 56.0 – – 0.38 – – 684 – –

Measured (stockpiles) 4.1 3.4 3.3 0.74 0.76 0.72 97 83 77

Total surface stockpiles 60.1 3.4 3.3 0.40 0.76 0.72 781 83 77

Grand total 345.2 316.5 266.1 1.31 1.49 1.48 14,563 15,123 12,642

Mineral Resource classification per mining area

Area

Measured Indicated Inferred Total Mineral Resource

Tonnes

(Mt)

Grade

(g/t)

Gold

(koz)

Tonnes

(Mt)

Grade

(g/t)

Gold

(koz)

Tonnes

(Mt)

Grade

(g/t)

Gold

(koz)

Tonnes

(Mt)

Grade

(g/t)

Gold

(koz)

Open pit

Akontansi 42.5 1.32 1,807 102.5 1.18 3,876 5.3 0.94 159 150.3 1.21 5,842

Kottraverchy 17.2 1.70 939 1.8 1.27 73 – – – 19.0 1.66 1,011

Pepe/Mantraim 26.1 1.40 1,171 14.8 1.26 600 2.0 1.22 76 42.8 1.34 1,848

Teberebie 27.3 1.57 1,374 23.0 1.51 1,118 0.1 1.59 3 50.3 1.54 2,495

Total open pit 113.0 1.46 5,292 142.0 1.24 5,665 7.3 1.02 238 262.3 1.33 11,196

Underground

Akontansi – – – – – – 12.8 3.57 1,467 12.8 3.57 1,467

Kottraverchy – – – – – – 10.1 3.46 1,120 10.1 3.46 1,120

Total underground – – – – – – 22.8 3.52 2,587 22.8 3.52 2,587

Heap leach

re-treat and

stockpiles

South Heap Leach – – – 56.0 0.38 684 – – – 56.0 0.38 684

Surface stockpiles 4.1 0.74 97 – – – – – – 4.1 0.74 97

Total surface 4.1 0.74 97 56.0 0.38 684 – – – 60.1 0.40 781

Grand total 117.1 1.43 5,388 198.0 1.00 6,350 30.1 2.92 2,825 345.2 1.31 14,563

The post-depletion Mineral Resources and Mineral Reserves have decreased by 4% and 3%

respectively as a result of resource model changes and cost inputs outstripping the gold

price increase.


Modifying factors

�� The Measured and Indicated Mineral Resources are

inclusive of those Mineral Resources modified to produce

Mineral Reserves;

�� All Mineral Reserves are quoted in terms of RoM grades

and tonnages as delivered to the metallurgical processing

facilities and are therefore fully diluted; and

�� Mineral Resources and Mineral Reserves undergo regular

internal and/or external audits, and any issues identified

are rectified at the earliest opportunity.

Grade tonnage curves

Open pits

To

nnes (m

illio

ns)

Avera

ge g

rad

e a

bo

ve c

ut-

off (g

/t)

0.0 0.2 0.4 0.6 0.8 1.0 1.41.2 1.6 1.8 2.0

Cut-off grade (g/t)

350

300

250

200

150

100

50

0

3.0

2.5

2.0

1.5

1.0

0.5

0

Mineral ReservesThe Mineral Reserve estimate for Tarkwa Gold Mine is based on development of appropriately detailed and engineered LoM

plans. All design and scheduling work is undertaken to an applicable level of detail by experienced engineers using mine-

planning software. The planning process incorporates appropriate modifying factors and the use of cut-off grades and other

techno-economic investigations.

Mineral Reserve statements include only Measured and Indicated Mineral Resources modified to produce Mineral Reserves

contained in the LoM plan.

Mineral Reserve classification

Classification

Tonnes (Mt) Grade (g/t) Gold (koz)

Dec

2012

Dec 2011

Dec 2010

Dec 2012

Dec 2011

Dec 2010

Dec 2012

Dec 2011

Dec 2010

Open pit

Proved 103.9 118.1 122.5 1.29 1.30 1.26 4,305 4,943 4,982

Probable 129.3 143.6 109.5 1.20 1.15 1.19 4,996 5,328 4,192

Total open pit 233.2 261.7 232.1 1.24 1.22 1.23 9,300 10,271 9,174

Surface stockpiles

Proved 4.1 3.2 3.3 0.74 0.73 0.72 97 74 75

Probable South Heap Leach 56.0 – – 0.38 – – 684 – –

Total surface stockpiles 60.1 3.2 3.3 0.40 0.73 0.72 781 74 75

Grand total 293.3 264.8 235.3 1.07 1.21 1.22 10,081 10,345 9,249

Mineral Resource

parameters UnitsDec

2012

Dec2011

Gold price US$/oz 1,650 1,450

Cut-off for heap leach g/t 0.34 – 0.70 0.248

Cut-off for mill feed g/t 0.39 0.36

Cut-off for underground g/t 2.62 – 3.27 2.62-3.27

Mineral Reserve parameters Units

Dec2012

Dec2011

Gold price US$/oz 1,500 1,300

Cut-off for heap leach g/t 0.37 – 0.77 0.276

Cut-off for mill feed g/t 0.42 0.401

Strip ratio waste:ore 6.1 5.3

Dilution (open pits) % 11 11

Mining recovery factor % 100 100

MCF % 100 100

Plant recovery factor – fresh ore % 97 97

Plant recovery factor – oxide ore % 97 97

Heap leach recovery factor % 52 61

CIL Processing capacity Mtpa 12.3 12.3

Heap leach capacity Mtpa 9.8 9.8


Mineral Reserve classification per mining area

Area

Proved Probable Total Mineral Reserve

Tonnes

(Mt)

Grade

(g/t)

Gold

(koz)

Tonnes

(Mt)

Grade

(g/t)

Gold

(koz)

Tonnes

(Mt)

Grade

(g/t)

Gold

(koz)

Open pit

Akontansi 40.6 1.19 1,551 92.1 1.15 3,403 132.6 1.16 4,954

Kottraverchy 12.1 1.49 579 0.2 1.10 7 12.3 1.48 586

Pepe/Mantraim 24.5 1.24 975 8.8 1.12 317 33.3 1.21 1,291

Teberebie 26.7 1.40 1,200 28.2 1.40 1,269 55.0 1.40 2,469

Total open pit 103.9 1.29 4,305 129.3 1.20 4,996 233.2 1.24 9,300

Spent Ore (South Heap Leach) 56.0 0.38 684 56.0 0.38 684

Surface stockpiles 4.1 0.74 97 – – – 4.1 0.74 97

Grand total 108.0 1.27 4,402 185.3 0.95 5,680 293.3 1.07 10,081

Mineral Resources and Mineral Reserves reconciliation year-on-year

Factors that affected Mineral Resource reconciliation

�� Depletion by mining (RoM and low-grade ore);

�� Changes to the Pepe-Atuabo-Mantraim-Teberebie

Resource and Akontansi models;

�� Economic factors resulting from the increase in cost

inputs that marginally outstripped the increased gold

price; and

�� Inclusion of spent ore from South Heap Leach into

Mineral Resource.

Go

ld (M

oz)

14.560.40 0.010.01

0.68

0.85

15.12

Change in Mineral ResourcesDecember 2011 to December 2012

Sp

ent

Ore

Decem

ber

20

11

Min

ed

dep

letio

n

Reso

urc

e

mo

delling

Eco

no

mic

fa

cto

rs

Oth

er

Decem

ber

20

12

16

14

12

10

8

6

4

2

0

Mineral Reserve sensitivityThe Mineral Reserve Sensitivity has been derived from the

application of the relevant cut-off grades to individual grade

tonnage curves of the optimised pit shells for the open pits.

The Mineral Reserve sensitivities are not based on detailed

depletion schedules and should be considered on a relative

and indicative basis only. The following graph indicates the

Managed Mineral Reserve sensitivity at -10%, -5%, Base

(US$1,500), +5%, +10% and +25% to the gold price.

Factors that affected Mineral Reserve reconciliation

�� Depletion by mining (RoM and low grade);

�� Increase in cost inputs marginally outstripped the

increased gold price;

�� Minor changes due to design change; and

�� Inclusion of spent ore from South Heap Leach into

Mineral Reserve at end of LoM.

Managed Mineral Reserve sensitivity

Go

ld (M

oz)

10.98

10.6810.50

10.08

9.60

9.28

(-10%) (-5%) (Base)1,500

(+5%)

Gold price (US$/oz)

(+10%) (+25%)

11.5

11.0

10.5

10.0

9.5

9.0

8.5

8.0

Go

ld (M

oz)

0.07 0.03

10.08

0.00 0.00

0.68

0.85

10.35

Change in Mineral ReservesDecember 2011 to December 2012

Sp

ent

Ore

Decem

ber

20

11

Min

ed

dep

letio

n

Reso

urc

e

mo

delling

Exclu

sio

n

Eco

no

mic

fa

cto

rs

Oth

er

Decem

ber

20

12

12

10

8

6

4

2

0


10. Competent Persons

Competent Persons

Godfred Baba Avane: Mineral Resources Manager

MSc (Hons) (Geological Engineering); (MAusIMM; Registration number 309400). Mr Avane has over 17 years’ experience in

the mining industry and is the lead Competent Person, responsible for overall Mineral Resource Management for Tarkwa.

Robert van der Westhuizen; Regional Chief Strategic Planning Engineer

BSc (Hons) (Geology); MSc (Mining) (MAusIMM; Registration number 223783). Mr van der Westhuizen has 33 years’

experience in the mining industry and is responsible for the overall correctness, standard and compliance of the LoM

planning, scheduling, reserve statement and financial analysis for Tarkwa.

John A Searra: Chief Resource Geologist

BSc (Hons) (Geology); MSc (Engineering). Mr Searra has over 27 years’ experience in the mining industry and is responsible

for sampling, geology, exploration and resource estimation for Tarkwa.

Internal technical reviews have been conducted by the Competent Persons as listed, who

are full-time employees of Gold Fields Limited.

Aerial view of metallurgical complex


11. Key technical staff

Post Incumbent Qualifications Years Key responsibilities

General Manager Michiel van der

Merwe

BEng Extractive Metallurgy 16 Responsible for the overall strategic

direction, leadership and

management

Manager Mining Stephen Osei

Bempah

BSc Mining Engineering 29 Full operational management

Mineral Resources

Manager

Godfred Baba

Avane

MSc Geological Engineering 17 Mineral resource management

Financial Manager Hein Muller BCom Accounting 24 Financial reporting and compliance

Human Resources

Manager

Mohammed

Abubakari

MPA, BA Hons Economics, ACCA 17 Human resource management

Metallurgy

Manager Heap

Leach

Casper

Dzomeku

MSc Minerals Engineering, MCSM,

Exec MBA

28 Mineral processing and metallurgy

heap leach

Metallurgy

Manager CIL

George Nutor BSc Mineral Engineering 19 Mineral processing and metallurgy

CIL

Engineering

Manager –

Process

H de Beer Diploma Mechanical Engineering

Government Certificate of

Competency

29 Process engineering, logistics and

infrastructure management

Safety Manager D Pienaar NADSAM (M+3) 24 Health and safety

Environmental

Manager

Ben Addo BSc Chemistry, MSc

Environmental management

19 Environmental management

Engineering

Manager HME

A Landsberg National Higher Diploma

Mechanical Engineering

21 Heavy mining equipment

North Heap Leach facility

Gold Fields LimitedTarkwa Gold Mine

Plan showing mine infrastructure as at 31 December 2012

Page w

idth 208 mm

Page w

idth 205 mm

12. Brief history

The history of Tarkwa

Late 1800s: Several small mining companies operated the Abontiakoon concession.

1935: Amalgamated Banket Area Limited (ABA) acquired the Abontiakoon concession. Sinking of the

Abontiakoon vertical shaft.

1936 – 1940: Construction of new central mill with a capacity of 30 ktpm.

1960: All workings abandoned and allowed to flood.

1961: Production restarted under the State Gold Mining Corporation.

1963: The Tarkwa mines renamed Tarkwa Goldfields Limited.

1973 – 1976: Apinto Shaft sunk to access additional ore sources.

1993: GFGL signed a management contract with the Ghanaian government to operate the mine.

1996: Feasibility study completed by GFGL on an open pit/heap leach operation.

1998: Initial Tarkwa Phase I development completed for an open pit operation mining 14.5 Mtpa including

4.7 Mtpa of heap leach feed ore.

1999: Tarkwa Phase II expansion completed to increase mining rate to 20.7 Mtpa and with heap leach ore

production to 7.2 Mtpa. All underground operations and associated processing plant ceased production.

2000: GFGL acquired northern area of Teberebie. Mining production pushed to 36 Mtpa.

2004: Tarkwa implemented owner mining in July 2004 and commissioned a CIL plant with a nameplate capacity

of 4.2 Mtpa in October 2004.

2008: South Heap Leach facility ceases crushing in December 2008.

2009: Expanded CIL plant commissioned in January 2009, design throughput of 12.3 Mtpa achieved in

September 2009. HPGR 1 Mt plant scale test conducted at South Heap Leach facility in last quarter of

the year.

2010: Conversion to owner maintenance implemented with the inherent cost savings and productivity gains

expected to materialise in 2011.

2011: Gold Fields Ghana Limited acquired the 18.9% IAMGold interest in Tarkwa and now holds 90% with the

remaining 10% held by the Ghanaian government.

2012: CIL Secondary crushing plant commissioned and South Heap Leach stopped.

Photographs showing the recently installed water purification system


Akontansi Cut 7 looking East, Tarkwa

Tarkwa Mineral Resource and Mineral Reserve classification

EXPLORATIONRESULTS

MINERALRESERVES

MINERALRESOURCES

Reported as in situmineralisation estimates

Consideration of mining, metallurgical, economic, marketing, legal,environmental, social and governmental factors (the ‘modifying factors’)

345.2 Mt @ 1.3 g/t14.6 Moz

293.3 Mt @ 1.07 g/t10.1 Moz

185.3 Mt @ 0.95g/t5.7 Moz

108.0 Mt @ 1.27 g/t4.4 Moz

30.1 Mt @ 2.92 g/t2.8 Moz

198.0 Mt @ 1.00 g/t6.3 Moz

117.1 Mt @ 1.43 g/t5.4 Moz

Reported as mineableproduction estimates

Incr

easi

ng le

vel o

f geo

scie

ntifi

c kn

owle

dge

and

confi

denc

e

MEASURED PROVED

PROBABLEINDICATED

INFERRED


This Technical Short Form Report (the Report) contains information as at 31 December 2012 (the Effective Date of this

Report). The statements and information set out in this Report speak only as of the Effective Date of this Report. Shareholders

and other interested and affected parties are therefore urged to review all public disclosures made by Gold Fields after the

Effective Date of this Report, as some of the information contained in the Report may have changed or been updated. Gold

Fields does not undertake any obligation to update publicly or release any revisions to statements and information set out in this

Report to reflect events or circumstances after the Effective Date of this Report, or to reflect the occurrence of unanticipated

events, unless obliged to do so pursuant to law or regulation. In such event, Gold Fields does not undertake to refer back to

any information contained in this Report.

Notes

BASTION GRAPHICS

Open pit mining operations

Registered Office South Africa:

150 Helen RoadSandownSandton, 2196JohannesburgGauteng

Private Bag X30500Houghton, 2041South Africa

Website: http://www.goldfields.co.zaTelephone: +27 (0) 11 562 9700Facsimile: +27 (0) 11 562 9838

“If we cannot mine safely, we will not mine”

Gold Fields Safety Value

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