West Africa Region
Salient features
- Significant Mineral Reserve increase at Damang
- Plant expansion at Tarkwa completed
- Installation of a secondary crusher at the Damang plant is in progress
- Mineral Resource 20.5 Moz
- Mineral Reserve 12.5 Moz
Tarkwa Gold Mine
Mineral Resource 16.2 Moz
Mineral Reserve 10.7 Moz
- Robust long life Mineral Reserve to
anchor growth in Region
- Maintenance of mining flexibility and
security of supplies remain a priority
- CIL feed now optimised over the LoM
Damang Gold Mine
Mineral Resource 4.3 Moz
Mineral Reserve 1.8 Moz
- Significant brownfields opportunities
- Damang Pit Cutback position
continues to grow
- Mineral Reserve increased 34%
year-on-year
|
Gold Fields’ West Africa Region
operations are located in the southern
area of western Ghana, 300 km by road
west of the capital of Accra and some
60 to 90 km southeast of the port city
of Takoradi. The orebodies are located
within the Tarkwaian System, which forms
a significant portion of the stratigraphy of
the Ashanti Belt in Ghana.
Gold Fields acquired the Tarkwa
underground gold mine from the State
Gold Mining Company of Ghana on 1
July 1993. Open cast and Heap Leach
operations began in 1998, while the
underground operations were suspended
in mid 1999. The successful development
of Tarkwa has enabled Gold Fields to
increase its geographic and operational
diversity by expanding internationally,
while broadening its scope to include,
not just deep level mining, but also
surface operating mines.
Gold Fields Ghana Limited (GF Ghana)
was incorporated in Ghana in 1993 and
includes:
- 71.1% interest in GF Ghana which
holds a 100% interest in Tarkwa Gold
Mine (Tarkwa);
- IAMGold, through its affiliates, holds
18.9%; and
- Government of Ghana holds a 10% free
carried interest.
- A 71.1% interest in Abosso
Goldfields Limited (AGL), which
holds a 100% interest in Damang
Gold Mine (Damang), while Repadre
International Corporation (being a
wholly owned subsidiary of IAMGold)
holds 18.9% and the Ghanaian
government holds the remaining
10%. Gold Fields acquired the
Damang Gold Mine from Ranger
Minerals in January 2002.
Annual overview
The West Africa Region Mineral
Resources have increased by 8% to 20.5
(18.9) Moz, whilst the Mineral Reserves
decreased by 1% to 12.5 (12.7) Moz,
depleted by 1.0 and 1.0 Moz respectively.
Furthermore, at Tarkwa, the decrease
in Mineral Reserves (690 koz) is largely
attributable to production depletion
(~800 koz) with marginal positive
contributions from gold price and
orebody modelling.
The post depletion Mineral Reserve
ounces increased by 34% at Damang,
primarily through a significant increase at
Huni on the northern side of the Damang
Pit Cutback (DPCB) following the pit
optimisation at gold price US$800/oz.
The DPCB continues to provide a window
of opportunity to explore attractive targets
and increase the mines operational
footprint. The potential for further open
pit mining at Damang will be evaluated
during F2010 and is part of a three year
program to grow Damang beyond its
current Life of Mine.
The following points are noteworthy:
- The CIL Plant expansion project at
Tarkwa was commissioned in January
2009 and as a result, the CIL feed has
been optimised in the LoM scheduling.
The plant expansion increases the
overall CIL capacity to 12.3 Mtpa.
In addition, the Heap Leach (HL)
treatment route has a capacity of
9.8 Mtpa, translating to a combined CIL
and HL production of between 700 koz to
800 koz per annum;
- Processing at the South Heap
Leach was phased out in December
2008 and the current focus is on
constructing a High Pressure Grinding
Roll (HPGR) pilot plant to conduct a
1.0 Mt plant scale test of the technology
during F2010. The tests will determine
the viability of increased recoveries
that potentially could be achieved via
this process;
- Delivery on optimising processing
options, maintenance of mining
flexibility and cost effective supply of
commodities, fuel and power are key
to ensuring Tarkwa maintains margin
and Notional Cash Expenditure (NCE)
targets;
- The Hellman & Schofield Multiple
Indicator Kriging (MIK) model for
the DPCB complex was replaced by
an updated constrained composite
version this year; and
- Installation of a secondary crusher
at the Damang Processing Plant is
planned for completion by the fourth
quarter of F2010. The objective is to
mitigate the current dependency on
oxide ore and facilitate blending ratios
of up to 95% fresh ore and 5% oxide
ore.
Mineral Resources and Mineral Reserves 1
|
GHANA OPERATIONS |
|
|
|
|
|
|
|
Tarkwa |
|
|
Tarkwa |
|
|
|
|
Measured |
6.914 |
|
Proved |
|
6.371 |
|
|
Indicated |
6.021 |
|
Probable |
|
4.857 |
|
|
Inferred |
2.411 |
|
|
|
|
|
|
Total |
344.1 |
|
1.5 |
|
16.075 |
|
15.346 |
|
Total |
|
265.6 |
|
1.2 |
|
10.575 |
|
11.228 |
|
|
Measured low-grade stockpiles |
0.090 |
|
Proved low-grade stockpiles |
|
0.085 |
|
|
Tarkwa Total |
348.7 |
|
1.4 |
|
16.187 |
|
15.435 |
|
Tarkwa Total |
|
270.0 |
|
1.2 |
|
10.676 |
|
11.313 |
|
|
Damang |
|
|
Damang |
|
|
|
|
Measured |
0.680 |
|
Proved |
|
0.388 |
|
|
Indicated |
1.309 |
|
Probable |
|
0.800 |
|
|
Inferred |
1.336 |
|
|
|
|
|
|
Total |
69.9 |
|
1.8 |
|
4.100 |
|
3.325 |
|
Total |
|
31.0 |
|
1.7 |
|
1.636 |
|
1.189 |
|
|
Indicated low-grade stockpiles |
0.165 |
|
Proved low-grade stockpiles |
|
0.165 |
|
|
Damang Total |
74.9 |
|
1.8 |
|
4.283 |
|
3.490 |
|
Damang Total |
|
36.1 |
|
1.6 |
|
1.820 |
|
1.354 |
|
|
Total West Africa Region |
423.6 |
|
1.5 |
|
20.470 |
|
18.925 |
|
Total West Africa Region |
|
306.1 |
|
1.3 |
|
12.496 |
|
12.667 |
|
1 |
Mineral Resource are inclusive of Mineral Reserves; Managed, unless otherwise stated. |
Mineral Reserve sensitivities
The sensitivity of Mineral Reserve ounces at all the operations is shown in the
accompanying chart, at -5%, -10% and +5%, +10% and +25%, relative to the
base gold price used for this declaration.
The Mineral Reserve sensitivities are not based on detailed depletion schedules
and should be considered on a relative and indicative basis only.
West Africa Region Mineral Reserve Sensitivity
|
Grade control drilling, Damang Gold Mine, Ghana |
|
CIL Processing Plant, Tarkwa Gold Mine, Ghana |
|