Iamgold Reports 39% Increase IN Reserves at Essakane Based ON Heap Leach Pre-Feasibility Study and Higher Grade Intercepts, Increasing Future Average Annual Production to 480,000 Ounces
NEWS RELEASE
TSX: IMG NYSE: IAG
IAMGOLD REPORTS 39% INCREASE IN RESERVES AT ESSAKANE
BASED ON HEAP LEACH PRE-FEASIBILITY STUDY AND HIGHER GRADE INTERCEPTS,
INCREASING FUTURE AVERAGE ANNUAL PRODUCTION TO 480,000 OUNCES
All amounts are in US dollars, unless otherwise indicated.
Numbers in tables may not add due to rounding.
Toronto, Ontario, June 5, 2018 – IAMGOLD Corporation (“IAMGOLD” or the “Company”) today
announced positive results from a Pre-feasibility Study ("PFS") for its Essakane Heap Leach Project (the
“Project”) in Burkina Faso, West Africa. The results, which outline an economically viable project, justify the
commencement of a Feasibility Study (“FS”) to further optimize the project development design, secure
long lead equipment and improve project economics.
PRE-FEASIBILITY HIGHLIGHTS (100% BASIS)
Probable Reserves increased by 39%, or 1.3 million ounces, to 4.7 million ounces.
Indicated Resources increased by 19%, or 0.8 million ounces, to 5.1 million ounces.
Inferred Resources increased by 54%, or 0.2 million ounces, to 0.6 million ounces.
Mine Life of 8.5 years (2018-2026) with mill throughput of 12.0 million tonnes per annum and heap
leach throughput of 10.0 million tonnes per annum (2020-2026).
Mine life extended by three years from the LOM reported in the 2016 Technical Report, with
potential to extend further with the FS and the drilling of prospective satellite prospects near
Essakane.
Average annual production increases by 16% to 480,000 ounces versus previously disclosed plan,
once heap leach is operational.
Peak annual production exceeding 500,000 ounces.
LOM cash costs of $707/oz and all-in sustaining costs of $946/oz.
Heap Leach initial capital expenditures of $155 million.
The infill drilling program, conducted to upgrade targeted lower-grade inferred resources in support of the
Heap Leach PFS, intersected higher grades than anticipated in several areas. The impact of these results
is still being assessed and may provide potential to outline additional zones of higher-grade mineralization
for processing at the existing carbon-in-leach (“CIL“) plant. The drilling campaign is continuing and the
results will be used to complete the delineation of both the lower-grade heap leach and higher-grade CIL
mineralization to optimize the development options as part of the recomm ended FS.
“I applaud the Essakane team,” said Steve Letwin, President and CEO of IAMGOLD. “Not only have they
introduced a new processing method that allows for economic incremental production, their success at the
drill bit has delivered a resource increase far greater than what we expected. While we knew that heap
leaching had the potential to unlock additional reserves, we were positively surprised at, and benefited
from, intercepting higher grades, which account for more than one-third of the 39% increase. Essakane is
pursuing all avenues for enhancing the value of this already high-performing operation, including targeting
additional resources from Essakane’s large, prospective land package. Stay tuned for an initial resource
estimate for the Gossey prospect in the fourth quarter of this year. With these positive results and the
future work we have planned, we are targeting a mine life beyond 2030 and AISC below $900 an o unce.”
The PFS was completed jointly by IAMGOLD and Kappes, Cassiday & Associates (KCA), with inputs from
technical studies completed by other consultants, and has an effective date of June 5, 2018. The PFS
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represents a comprehensive study of the technical and economic viability of a mineral project that has
advanced to a stage where a preferred mining method has been established and an effective method of
mineral processing has been determined. IAMGOLD is using the PFS to identify the preferred
development option to demonstrate economic viability of the Project, to support Mineral Reserve
disclosure, and to identify additional work recommended to support the completion of a FS. Technical
studies to support the completion of the FS have commenced, with the study scheduled for completion in
the first quarter of 2019. As a result of the newly established reserve estimate, and the intercepted high-
grade material at depth, the FS will also evaluate a lower capital option focused on enhancing the CIL
plant only to potentially reduce the LOM AISC while improving the LOM NPV.
A technical report summarizing the PFS will be filed on SEDAR within 45 days of the date of this news
release.
PFS HIGHLIGHTS
US$/C$ exchange rate of 1:1.25. US$/€ exchange rate of: 1:0.83
*Initial capital expenditures exclude fleet
MINERAL RESOURCES
The Mineral Resource estimate used as the basis for the study is summarized below.
Mineral Resources (100% Basis) – June 5, 2018
Classification Tonnes
(000)
Grade
(g/t Au)
Contained Ounces
(000)
Indicated 167,067 0.95 5,101
Inferred 20,994 0.88 595
Notes:
1. CIM Definition Standards were followed for classification of Mineral Resources.
2. Mineral Resources reported at a cut-off grade for Essakane main zone of 0.33 g/t Au for saprolite, 0.43 g/t Au
for transition material and 0.30 g/t Au for fresh rock material. Cut-off grades for Falagountou are 0.36 g/t Au
for saprolite, 0.46 g/t Au for transition material and 0.52 g/t Au for fresh rock material.
3. Mineral Resources do not include 2018 depletion.
4. Mineral Resources are constrained within a pit shell estimated using a long-term gold price of $1,500/oz and
a US$/€ exchange rate of: 1:0.77 and a US$/CFA exchange rate of 1:0.00198.
5. Mineral Resources are inclusive of Reserves quoted below.
6. Mineral Resources are reported on a 100% basis.
Project Economics and Key Parameters
Mining Capacity 70.0 Mtpa
Carbon-in-leach (CIL) Milling Capacity 12.0 Mtpa
Heap Leach (HL) Processing Capacity 10.0 Mtpa
LOM Average Annual Gold Production (CIL, 8.5 years) 416,000 oz.
LOM Average Annual Gold Production (HL, 6.5 years) 72,000 oz.
LOM Average Annual Gold Production (8.5 years) 471,000 oz.
LOM Average Recovery Rate (CIL) 92.1%
LOM Average Recovery Rate (HL) 55.0%
Mine Life (2018-2026) 8.5 years
LOM Average Cash Costs (incl. Royalties) $707/oz
LOM Average AISC $946/oz
Average diluted grade CIL 1.17 g/t Au
Average diluted grade HL 0.43 g/t Au
Average LOM Strip Ratio (Remaining Pit) 2.34:1
Estimated Initial Capital Expenditure* (millions) $155
Gold Price Assumption used in financial analysis $1,275/oz
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MINERAL RESERVES
The tonnes, grades, and classification of the Mineral Reserves captured within the PFS mine plan are
summarized below.
Mineral Reserve (100% Basis) – June 5, 2018
Process Classification Tonnes
(000)
Grade
(g/t Au)
Contained Ounces
(000)
CIL Proven - - -
Probable 88,146 1.26 3,581
Stockpile 14,442 0.58 278
Total CIL 102,588 1.17 3,859
Heap
Leach
Proven - - -
Probable 58,209 0.42 790
Stockpile 3,657 0.47 55
Total Heap Leach 61,866 0.43 845
Total 164,454 0.89 4,704
Waste within Designed Pit 342,944
Ore within Designed Pit 146,355
Total Tonnage within Designed Pit 489,299
Notes:
1. Reserves estimated assuming open pit mining methods.
2. Reserves are based on a gold price of $1,200/oz.
3. Average weighted CIL process recovery of 92.1% and Heap Leach process recovery of 55.0%.
4. Mining costs ($/t mined): $2.55/t. Processing costs: $12.36/t (CIL). Processing costs $3.13/t (HL).
General and Administrative costs (includes refining cost) of $3.99/t for CIL only. Heap Leach bears no
G&A costs.
5. Mineral Reserves are reported on a 100% basis.
6. Mineral Reserves do not include 2018 depletion.
7. Mineral reserves include material from Essakane main zone and Falagountou pits.
MINING AND PROCESSING
The PFS has identified the positive benefit of two extra mining phases to the existing Essakane main zone
(EMZ) open pit mining operation combined with the addition of a heap leaching operation. The heap
leaching operation would be run in parallel to the existing process plant. Dedicated primary (gyratory) and
secondary (cone) crushing circuits, tertiary crushing using a high pressure grinding rolls (HPGR) unit,
material handling and stacking conveyors, and a carbon in column (CIC) adsorption plant would be
installed. Loaded carbon would be transported to the existing plant facilities for stripping and refining
where minimal infrastructure upgrade would be required. Where possible, the specified equipment would
be the same model as that used in the CIL plant to improve maintainability and to reduce parts inventories.
Additional major infrastructure included in the PFS are the leach pad, solution distribution and collection
systems, solution ponds, camp upgrade and power generation capacity increase.
Remaining open pit mining includes approximately 343 Mt of waste and 146 Mt of ore over an 8.5-year-
period of production mining. This volume of waste would decrease if in-pit inferred resources can be
converted to CIL or Heap Leach ore through infill drilling. Stockpile reclaim would commence in 2020 until
depletion at the end of the mine life. Maximum mining rate is 70 Mt per annum. The average mined grade
is 0.94 g/t Au and the LOM stripping ratio is 2.34:1.
The average processed grade is 0.89 g/t (1.17 CIL and 0.43 HL).
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FUTURE WORK
The PFS recommends the completion of a FS to validate and detail the elements of the development
concept set out in the PFS, and would include additional infill and condemnation drilling, additional lab
column testing , engineering studies and construction planning.
Environmental studies, resettlement action planning and permitting initiatives which have all been initiated
during the PFS stage will also continue during the FS. Environmental and social baseline evaluation has
been completed and a permit application is planned for the third quarter 2018.
The recommended FS work has already been initiated and is expected to be completed in the first quarter
of 2019, using a 10 Mt per annum heap leaching processing rate. In addition, the FS will evaluate additional
development alternatives, such as a gravity circuit upgrade and an increase in grinding capacity. This
strategy aims to increase the throughput and recovery of the CIL and gravity circuits in parallel, in order to
bring additional value to the processing plant.
QUALIFIED PERSONS
The 2018 Essakane Heap Leach PFS was prepared by IAMGOLD and Kappes, Cassiday & Associates,
and incorporates the work of IAMGOLD and Kappes, Cassiday & Associates, SRK consulting, Soutex and
GMining (QPs) (as defined under National Instrument 43-101). KCA’s, SRK, Soutex and GMining Qualified
Persons are independent of IAMGOLD and have reviewed and approved this news release. IAMGOLD
Qualified Persons are not independent of IAMGOLD and have reviewed and approved this news release.
The affiliation and areas of responsibility for each Qualified Person involved in preparing the 2018
Essakane Heap Leach PFS, upon which the technical report will be based, are:
IAMGOLD QPs
V. Blanchet, Eng., Property description and location, accessibility, climate, local resources,
infrastructure and physiography, history, geological setting and mineralization, deposit type,
exploration, drilling, sample preparation and analysis and security, data verification, and mineral
resource estimate
P. Chabot, Eng., Mining method and mineral reserve estimate
R. Beauprie, Eng., Recovery method – CIL, mineral processing and metallurgical testing - CIL
D. Isabel, Eng., Environmental studies, permitting, and social or community impacts
L-B Denoncourt, Eng., Infrastructure, market studies and contract, capital and operating cost
estimate, financial evaluation, other relevant data and information
KCA QPs
T. Manning, P. Eng., Mineral processing and metallurgical testing – Heap Leach, Recovery
method – Heap Leach, Heap leach infrastructure, Heap leach operating costs
SRK QPs
E. Saunders, P. Eng., Open pit mine stability, waste rock pile stability
C.Scott, P. Eng., Heap leach stability
Soutex QPs
E. Bouchard-Marchand, Eng., CIL plant upgrade (Strip circuit, carbon handling, refining)
GMining QPs
R. Sirois, Eng., Falagountou deposit resource
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The information in this news release was reviewed and approved by Lise Chénard, Eng., Director Mine
Geology and Daniel Vallières, Eng., Director Technical Services. Both Ms. Chénard and Mr. Vallières work
for IAMGOLD and are Qualified Persons as defined by National Instrument 43-101.
Forward-Looking Information
All Mineral Reserve and Mineral Resources estimates reported by the Company were estimated in
accordance with the Canadian National Instrument 43-101 and the Canadian Institute of Mining,
Metallurgy, and Petroleum Definition Standards (May 10, 2014). These standards differ significantly from
the requirements of the U.S. Securities and Exchange Commission. Mineral Resources which are not
Mineral Reserves do not have demonstrated economic viability.
This document contains "forward-looking information" within the meaning of Canadian securities legislation
and "forward-looking statements" within the meaning of the United States Private Securities Litigation
Reform Act of 1995. This information and these statements, referred to herein as "forward -looking
statements" are made as of the date of this document. Forward-looking statements relate to future events
or future performance and reflect current estimates, predictions, expectations or beliefs regarding future
events and include, but are not limited to, statements with respect to:
(i) the estimated amount and grade of Mineral Resources and Mineral Reserves;
(ii) the PFS representing a viable development option for the Project;
(iii) estimates of the capital costs of constructing mine facilities and bringing a mine into production, of
sustaining capital and the duration of financing payback periods;
(iv) the estimated amount of future production, both produced and metal recovered; and,
(v) estimates of operating costs and total costs, net cash flow, net present value and economic returns
from an operating mine.
Any statements that express or involve discussions with respect to predictions, expectations, beliefs,
plans, projections, objectives or future events or performance (often, but not always, using words or
phrases such as "expects", "anticipates", "plans", "projects", "estimates", "envisages", "assumes",
"intends", "strategy", "goals", "objectives" or variations thereof or stating that certain actions, events or
results "may", "could", "would", "might" or "will" be taken, occur or be achieved, or the negative of any of
these terms and similar expressions) are not statements of historical fact and may be forward -looking
statements.
All forward-looking statements are based on IAMGOLD's or its consultants' current beliefs as well as
various assumptions made by them and information currently available to them. The most significant
assumptions are set forth above, but generally these assumptions include:
(i) the presence of and continuity of metals at the Essakane mine at estimated grades;
(ii) the geotechnical and metallurgical characteristics of rock conforming to sampled results including
the quantities of water and the quality of the water that must be diverted or treated during mining
operations;
(iii) the capacities and durability of various machinery and equipment;
(iv) the availability of personnel, machinery and equipment at estimated prices and within the
estimated delivery times;
(v) currency exchange rates;
(vi) metals sales prices and exchange rate assumed;
(vii) appropriate discount rates applied to the cash flows in the economic analysis;
(viii) tax rates and royalty rates applicable to the proposed mining operation;
(ix) the availability of acceptable financing under assumed structure and costs;
(x) anticipated mining losses and dilution;
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(xi) metallurgical performance;
(xii) reasonable contingency requirements;
(xiii) success in realizing proposed operations;
(xiv) receipt of permits and other regulatory approvals on acceptable terms; and
(xv) the fulfillment of environmental assessment commitments and arrangements with local
communities.
Although management considers these assumptions to be reasonable based on information currently
available to it, they may prove to be incorrect. Many forward-looking statements are made assuming the
correctness of other forward looking statements, such as statements of net present value and internal
rates of return, which are based on most of the other forward-looking statements and assumptions herein.
The cost information is also prepared using current values, but the time for incurring the costs will be in the
future and it is assumed costs will remain stable over the relevant period.
By their very nature, forward-looking statements involve inherent risks and uncertainties, both general and
specific, and risks exist that estimates, forecasts, projections and other forward-looking statements will not
be achieved or that assumptions do not reflect future experience. We caution readers not to place undue
reliance on these forward-looking statements as a number of important factors could cause the actual
outcomes to differ materially from the beliefs, plans, objectives, expectations, anticipations, estimates
assumptions and intentions expressed in such forward-looking statements. These risk factors may be
generally stated as the risk that the assumptions and estimates expressed above do not occur as forecast,
but specifically include, without limitation: risks relating to variations in the mineral content within the
material identified as Mineral Resources and Mineral Reserves from that predicted; variations in rates of
recovery and extraction; the geotechnical characteristics of the rock mined or through which infrastructure
is built differing from that predicted, the quantity of water that will need to be diverted or treated during
mining operations being different from what is expected to be encountered during mining operations or
post closure, or the rate of flow of the water being different; developments in world metals markets; risks
relating to fluctuations in the Canadian dollar relative to the US dollar; increases in the estimated capital
and operating costs or unanticipated costs; difficulties attracting the necessary work force; increases in
financing costs or adverse changes to the terms of available financing, if any; tax rates or royalties being
greater than assumed; changes in development or mining plans due to changes in logistical, technical or
other factors; changes in project parameters as plans continue to be refined; risks relating to receipt of
regulatory approvals; delays in stakeholder negotiations; changes in regulations applying to the
development, operation, and closure of mining operations from what currently exists; the effects of
competition in the markets in which IAMGOLD operates; operational and infrastructure risks and the
additional risks described in IAMGOLD’s Annual Information Form filed with SEDAR in Canada (available
at www.sedar.com ) for the year ended December 31, 2017 and in the Corporation's Annual Report Form
40-F filed with the U.S. Securities and Exchange Commission on EDGAR (available at
https://www.sec.gov/edgar/searchedgar/companysearch.html. IAMGOLD cautions that the foregoing list of
factors that may affect future results is not exhaustive.
When relying on our forward-looking statements to make decisions with respect to IAMGOLD, investors
and others should carefully consider the foregoing factors and other uncertainties and potential events.
IAMGOLD does not undertake to update any forward-looking statement, whether written or oral, that may
be made from time to time by IAMGOLD or on our behalf, except as required by law.
About IAMGOLD
IAMGOLD (www.iamgold.com) is a mid-tier mining company with four operating gold mines on three
continents. A solid base of strategic assets in North and South America and West Africa is complemented
by development and exploration projects and continued assessment of accretive acquisition opportunities.
IAMGOLD is in a strong financial position with extensive management and operational e xpertise.
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For further information please contact:
Ken Chernin, VP Investor Relations, IAMGOLD Corporation
Tel: (416) 360-4743 Mobile: (416) 388-6883
Laura Young, Director, Investor Relations, IAMGOLD Corporation
Tel: (416) 933-4952 Mobile: (416) 670-3815
Martin Dumont, Senior Analyst Investor Relations, IAMGOLD Corporation
Tel: (416) 933-5783 Mobile: (647) 967-9942
Toll-free: 1-888-464-9999 [email protected]
Please note:
This entire news release may be accessed via fax, e-mail, IAMGOLD's website at www.iamgold.com and through CNW Group’s
website at www.newswire.ca. All material information on IAMGOLD can be found at www.sedar.com or at www.sec.gov.
Si vous désirez obtenir la version française de ce communiqué, veuillez consulter le
http://www.iamgold.com/French/accueil/default.aspx.