• Data Access
  • Your Email  
  • Your Email  
Keep me signed in.
Forgot your password?
Close
  • Forgot Your Password?
  • Enter the email you signed up with and we'll email it to you.
  • Your Email  
Close
Back
MDO
Mining Data Solutions
  • Home
  • Database
  • Subscribe
  • Sign In
  • Sign In
Canada
Westwood Mine

This page is not tailored to
devices with screen width under 750 px.
 Location:
39 km E from Rouyn-Noranda, Quebec, Canada

  Regional Office:
401 Bay Street, Suite 3200
Toronto
Ontario, Canada
M5H 2Y4
Phone  ...  Subscription required
Fax416-360-4750
EmailEmail
WebsiteWeb
Additional Resources for Suppliers & Investors
Drill results over 30 g/t Au
Stay on top of recent discoveries.
Search drill results by commodity and grade.
Largest mines in the Americas
Mining and mill throughput capaciites.
Full profiles of select mines and projects.
Deepest underground mines
Shaft depth and mill throughput data.
Full profiles of select mines and projects.
Heavy mobile equipment
HME type, model, size and quantity.
Full profiles of select mines and projects.
Permitting and construction projects
Projects at the permitting or construction stage. Full profiles of select projects.
Mines with remote camps
Camp size, mine location and contacts.
Full profiles of select mines and projects.
Mines & projects in Canada
A list of country's mines and projects.
Full profiles of select mines and projects.
  • Overview
  • Owners
  • Geology
  • Mining
  • Processing
  • Production
  • Reserves
  • Costs & Financials
  • Fleet
  • Personnel
  • Filings & News

Thank you for browsing through mine profiles compiled by the Mining Data Online team.

Would you like to subcribe or schedule a Demo?
  • Name:
     
  • Company:
     
  • Position:
     
  • Phone:
  • Email:
  • Message:

Overview

StatusTemporary Suspension
Mine TypeUnderground
Commodities
  • Gold
Mining Method
  • Underhand stoping
  • Longhole open stoping
  • Paste backfill
Processing
  • Gravity separation
  • Smelting
  • Carbon re-activation kiln
  • Centrifugal concentrator
  • Shaker table
  • Agitated tank (VAT) leaching
  • Carbon in leach (CIL)
  • Carbon in pulp (CIP)
  • Solvent Extraction & Electrowinning
  • Cyanide (reagent)
Mine Life2033
On November 2, 2020, the Company reported that a seismic event occurred at Westwood on October 30, 2020. All employees were brought safely above ground. The appropriate government authorities were notified and the cause of the seismic event is being investigated. Milling operations restarted on November 4, 2020 to process stockpile material and Grand Duc open pit ore. The Westwood underground mine operations are suspended pending the results of the investigation and while a business recovery plan is being assessed.
Latest NewsIAMGOLD Announces Temporary Workforce Reduction at Its Westwood Gold Mine     November 23, 2020


Owners

Source: p. 20
CompanyInterestOwnership
IAMGOLD Corp. 100 % Direct
The Westwood property is part of the Doyon division mining property.
The Doyon division mining property is held 100% by IAMGOLD Corporation.

Deposit Type

  • VMS
  • Vein / narrow vein
  • Intrusion related


Summary:

The origin of the gold in the Doyon-Bousquet-Laronde (DBL) mining camp has been extensively debated in the past and three models have been proposed: synvolcanic, multi-stage, and syn-deformation. Recent and current studies of the Laronde-Penna deposit, Westwood ore zones, and Mooshla intrusion mineralisation, combined with the geological synthesis of the DBL mining camp (Mercier-Langevin et al., 2009), have provided further insights into the synvolcanic model for the introduction of the gold.

Five deposit and occurrence styles are recognized in this camp: 1) gold-rich base metal massive sulphide lenses (Laronde-Penna, Bousquet 2-Dumagami and Warrenmac lens), 2) gold-rich vein stockworks and sulphide disseminations (Bousquet 1, Westwood and Ellison);, 3) intrusion-related Au-Cu sulphide-rich vein systems (Doyon, Mooshla-A), 4) shear-hosted Au-Cu-sulphide-rich veins (Mouska and MicMac) and 5) syn-deformation auriferous quartz-pyrite-tourmaline veins (Mooshla-B).

On the Westwood project, Zone 2 Extension mineralisation share similarities with the Doyon mine intrusion-related veins system while the Warrenmac-Westwood Corridor may be related with the volcanogenic massive sulphide lenses of the Laronde-Penna and Bousquet 2-Dumagami mines. The North Corridor mineralisation shows hybrid characteristics between the two previous corridors.

Excluding the Doyon Mine area, mineralisation in the Westwood deposit consists of multiple horizons grouped in three distinct mineralised corridors from North to south (Wright-Holfed et al., 2010; Mercier-Langevin et al., 2009): the Zones 2 Extension corridor, the North Corridor and the Warrenmac-Westwood Corridor. Gold is generally associated with the presence of base metal sulphides in each corridor.

The Zone 2 Extension mineralisation consists of quartz-pyrite veins and veinlets with variable but usually minor amounts of chalcopyrite and sphalerite. They are generally less than 15 centimetres thick and are hosted in sericitized wall rock containing 2 to 10% disseminated pyrite. The vein system is roughly oriented N85-105° with a dip varying between 60-70°S and is slightly discordant to the regional foliation and S0 planes (direction and dip). Free gold, at the origin of high-grade values, is frequently observed in those veins. The veins are highly strained and associated with a proximal sericite-pyrite-quartz-±garnet alteration assemblage. Analogies with the Doyon Mine’s intrusion-related Zone 2 may reflect a similar origin.

The North Corridor mineralisation is characterized by quartz-pyrite veins and/or concentrations with locally abundant sphalerite-chalcopyrite±pyrrhotite when approaching the Warrenmac-Westwood Corridor. The amount of sulphide is variable within centimetre- to decimetre-wide veins and veinlets. The system is generally parallel to the Zone 2 Extension corridor with a dip ranging from 70-80°S and is also weakly discordant from the regional foliation. Occasional free gold is also present in the veins. Mafic to intermediate volcanic rocks host the North Corridor. Some veins share some analogies with the Zone 2 Extension corridor veins while others are comparable to Warrenmac-Westwood veins, suggesting different, multiple or hybrid origins.

The Warrenmac-Westwood corridor consists of auriferous semimassive to massive sulphide lenses, veins and disseminations containing variable but significant amounts of Cu, Zn and Ag (Mercier-Langevin et al, 2009). The mineralisation is characterized by pyrite–sphalerite–chalcopyrite– pyrrhotite veins, stringers and massive sulphides associated with variable amount of quartz and rare visible gold and galena. The sulphides are also enriched in the epithermal suite of elements (e.g. As, Sb, Bi, Pb, Se, Te, and Hg). These ore zones are a few centimetres to more than 50 centimetres thick in a disseminated pyrite- and sericite-rich altered halo reaching thicknesses of up to 10 metres. Local massive to semimassive sulphide lenses ranging from 1 to 14 metres are also observed within the corridor. This corridor is thought to be a gold-rich volcanogenic massive sulphide horizon. The system is generally parallel to the Zone 2 Extension and North Corridor with dip ranging from 70-80°S, also weakly discordant to the regional foliation.


Mining Methods

  • Underhand stoping
  • Longhole open stoping
  • Paste backfill


Summary:

Development is classified as either deferred (infrastructure) development, including ramps, crosscuts and ore passes. Most of the lateral developments are mechanized, with jumbos, rockbolters, scissorlifts and 2.7m3 LHD units. Dimensions for waste drifts are generally 4.5m high and 4.1m wide. Drift dimensions in the ore lenses may vary locally according to the dip, width of the vein and mining method selected; planned drifts dimensions are 4.5m high and 4.5m wide for long hole drifts. Track drifts have been developed with wheeled long-tom crews: other than Level 840 (originally an exploration drift), dimensions are 2.9m high and 2.8m wide. No upcoming track drifts development work is out lined in the plan.

Arched backs are promoted for lateral development to enhance ground stability. Ground support varies significantly depending on the expected ground conditions and combination of static ground supports (rebars), yielding supports (hybrid bolts, debonded cables), long anchors (cables) and dynamic supports are used to control the wide spectrum of ground conditions experienced. In additions, mesh panels, straps and shotcrete are used either individually or conjointly as surface support. Ongoing monitoring of the ground support performance or possible deterioration are achieved by doing routinely workplace inspections. New ground support technologies are currently been trialled at the mine to optimize the performance of the ground support and to reduce exposure to potential ground hazard. Different bolting systems are currently been evaluated and mechanized bolters were acquired in 2018.

Vertical developments, such as ventilation raise and material handling passes,are typically inclusive to infrastructure development. Dimensions are typically 2.4 x 2.4m, although the main ventilation raise can reach up to4.3m in diameter.

Development performances are based on current performance at the Westwood Mine.
The following performances were used in the mine plan:
• Jumbo (deferred and stope prep) development: 6.0m/day/team;
• Jumbo development through paste backfill: 0.8m/day/team;
• Track drift and conventional development: 3.0m/day/team;
• Alimak raises: 2.0m/day/team;
• Conventional raises: 2.0m/day/team;
• Cables and 2": 100m/day/drill;
• Long Hole 4": 58m/day/drill (planned drilling);
• V-30 (slot) raises: 10m/day/drill

Long hole open stope (LHOS) is the primary mining method used at Westwood. Stopes are approximately 25 to30mhigh with a strike varying from 12to 15m in length. The mining width depends on the true width of the mineralization, lens configuration and geotechnical constraints applied for the area. Minimum mining width is set to 2.4m. The configuration of the access to the production stope are typically either transverse or longitudinal. Short longitudinal retreat is typically promoted for reducing delays associated to rehabilitation and exposure to induced stress.

Historically, mining sequence for long hole stopes has been carried out from bottom to top, either in a pillarless or in a primary and secondary stopes configuration. As depth increases over time in the LOM, an underhand (top to bottom) sequence is promoted for better induced stress management. Some considerations have been built in the LOM to mitigate colliding mining fronts creating diminishing pillars that are detrimental for stability. In additions, underhand sequence is known to be a mining method that is used in deep and ultra-deep mines that could reduce the exposure to seismicity on the top cut where production drilling is carried out. The main implication of an underhand retreat on the mining cycle consists in having to re-excavate the upper sill in the paste in order to allow the drilling of the underlying block. Stopes are generally being drilled down from the upper level with 100mm diameter holes. A drill pattern of 2.0 x2.0m is planned. ITH drills with V-30 heads will be used to open the slot raises.

Stopes will be blasted with emulsion explosives and electronic detonators. LHD units with remote capability will muck out the stope. Paste backfill will be poured in all stopes. A cure of 21 days is required before mining any adjacent stope and 28 days before excavating in paste. Most stopes will require cable bolts.

As part of the ground control management strategy, the seismicity is monitored throughout the mine. Westwood has a wide mine coverage micro seismic system implemented on site since 2013, with just under 100sensors been installed. Regular underground inspections and audits are performed as part of the quality assurance and quality controls programs. In additions, over 10,000m of geotechnical drilling were performed in 2019 and 2020 to refine the current geological and structural models of the mine.

Other mining methods (cut and fill, sub level) have been included in previous mining plan, but they are not included in the current mining plan.

Ore will be mucked using the LHD units to the nearest ore pass, generally located at less than 300 m. Thirteen tonnes haul trucks will be used for longer distances. Electrical trolleys with 10 t cars will be used to transport material from the various ore passes to the loading infrastructure for hoisting (capacity of 100 t per trip, up to 3,000 tpd. Two 20 t skips will be used for skipping material. Overall hoisting capacity depends on the loading pockets used (1,400 m or 1,920 m depth). On surface, 30 t trucks will transport ore the 2.5 km from the Westwood shaft to the Doyon mill.


Crushing and Grinding
Crusher / Mill TypeModelSizePowerQuantity
Jaw crusher 1.07m x 1.22m 1
SAG mill 2700 HP 1
Ball mill 1000 HP 1

Summary:

Ore Handling and Crushing
Underground ore is hoisted to surface and hauled by truck to the processing facility located 2.5km from the mine shaft. The ore is discharged at the crusher house. The ore is fed to a single stage jaw crusher (1.07 x 1.22m) by a front-end loader through a grizzly feeder. The ore is conveyed to the mill ore bins using a belt conveyor system. Each bin has a capacity of 2,800dmt.

Grinding and Gravity
Grinding of the Westwood ore is done using a 2,700HP semi-autogenous grinding (SAG) mill in closed circuit with primary hydrocyclones. The overflow of primary hydrocyclones feeds a 1,000-HP ball mill in closed circuit with its secondary hydrocyclones. A portion of the underflow (secondary hydrocyclones) feeds the gravity separation circuit composed of a sweco screen, Knelson concentrator (30’’) and a shaking table. The tail of the gravity circuit returns to the grinding circuit and the gravity gold concentrate goes to the refinery. The targeted grind size is 80% passing 53 microns (270 mesh).


Processing

  • Gravity separation
  • Smelting
  • Carbon re-activation kiln
  • Centrifugal concentrator
  • Shaker table
  • Agitated tank (VAT) leaching
  • Carbon in leach (CIL)
  • Carbon in pulp (CIP)
  • Solvent Extraction & Electrowinning
  • Cyanide (reagent)

Flow Sheet: Subscription required

Summary:

Leaching and Adsorption
The leaching circuit has 55 hours of retention time at the nominal processing rate of 3,106tpd. Leach residue is sent to cyanide destruction. At the nominal processing rate, retention time for each step of the leach and adsorption process is detailed as follows: primary leach tanks (4.7 hours), carbon-in-leach (CIL) tanks (6.6 hours), secondary leach tanks (31.3 hours) and carbon-in-pulp (CIP) tanks (12.1 hours).

Cyanide Destruction
The tailings are treated with SO2/Air cyanide destruction process. The leaches residues are split between to parallel detox reactors. In normal operation, a part of the process discharge residues is used to feed the paste backfill plant while the remainder is pumped to the Doyon open pit. A buffer tank (14h of backfill plant operation capacity) is maintained at maximum level with detoxified slurry to ensure continuous feed to backfill plant in case of temporary processing plant shutdown.

Paste Backfill ........

Recoveries & Grades:

CommodityParameter20202019201820172016201520142013
Gold Recovery Rate, %  ......  Subscription required  ......  Subscription required  ......  Subscription required  ......  Subscription required  ......  Subscription required  ......  Subscription required  ......  Subscription required  ......  Subscription required
Gold Head Grade, g/t 2.834.826.116.616.145.267.987.45
Subscription required - Subscription is required.

Production:

CommodityUnits2021202020192018201720162015
Gold koz  ......  Subscription required ^  ......  Subscription required  ......  Subscription required1291256560
All production numbers are expressed as metal in doré. ^ Guidance / Forecast.
Subscription required - Subscription is required.

Operational Metrics:

Metrics202020192018201720162015
Ore tonnes mined  ......  Subscription required  ......  Subscription required576 kt518 kt285 kt295 kt
Tonnes milled  ......  Subscription required  ......  Subscription required693 kt624 kt347 kt375 kt
Subscription required - Subscription is required.

Reserves at December 31, 2020:
Westwood Mineral Reserves have been estimated as of December 31, 2020 using a $1200/oz gold price and Mineral Resources have been estimated as of December 31, 2020 using a 5.5g/t Au cut-off grade over a minimum width of 2.4 metres. The Grand Duc Mineral Resources and Reserves estimates are included in the Westwood Mineral Resources and Reserves estimates. The Grand Duc Mineral Reserves have been estimated using a 0.42 g/t Au cut-off grade and a gold price of $1350/oz. Grand Duc Mineral Resources have been estimated using a 0.39 g/t Au cut-off grade and a gold price of $1500/oz.

CategoryTonnage CommodityGradeContained Metal
Proven 426 kt Gold 8 g/t 109 koz
Probable 3,527 kt Gold 4.6 g/t 517 koz
Proven & Probable 3,953 kt Gold 4.9 g/t 626 koz
Measured 907 kt Gold 13.2 g/t 384 koz
Indicated 6,299 kt Gold 6.1 g/t 1,240 koz
Measured & Indicated 4,764 kt Gold 10.2 g/t 1,557 koz
Inferred 7,071 kt Gold 8 g/t 1,809 koz

Commodity Production Costs:

CommodityUnits2020201920182017201620152014
Total cash costs Gold USD  ......  Subscription required  ......  Subscription required 884 / oz 824 / oz 894 / oz 1,001 / oz 822 / oz
All-in sustaining costs (sold) Gold USD  ......  Subscription required  ......  Subscription required 1,073 / oz 972 / oz 1,182 / oz 1,292 / oz 1,031 / oz
Subscription required - Subscription is required.

Financials:

Units202120202019201820172016
Capital expenditures (planned) M USD  ......  Subscription required
Sustaining costs M USD  ......  Subscription required  ......  Subscription required23.5  17.5   21.4  
Capital expenditures M USD  ......  Subscription required  ......  Subscription required55.1  61.1   85.8  
Revenue M USD  ......  Subscription required  ......  Subscription required160.5  161.5   88.2  
Operating Income M USD  ......  Subscription required  ......  Subscription required-1.9  4.5   -46.1  
Subscription required - Subscription is required


Heavy Mobile Equipment as of April 30, 2020:
HME TypeSizeQuantity
Bolter 13
Deck & Boom Trucks 3
Drill 5
Drill (long hole) 5
Drill jumbo (single boom) 10
Excavator 5
Grader 2
Personnel Carrier 51
Scissor Lift 24
Scoop Tram 23
Shotcreter 5
Truck (boom) 3
Truck (haul) 30 t 18

Mine Management:

Job TitleNameProfileRef. Date
....................... Subscription required ....................... Subscription required Subscription required Apr 30, 2020
....................... Subscription required ....................... Subscription required Subscription required Apr 30, 2020
....................... Subscription required ....................... Subscription required Subscription required Mar 26, 2021
....................... Subscription required ....................... Subscription required Subscription required Mar 26, 2021
Subscription required - Subscription is required.

Staff:

EmployeesContractorsTotal WorkforceYear
Subscription required Subscription required Subscription required 2020

Corporate Filings & Presentations:

DocumentYear
................................... Subscription required 2021
................................... Subscription required 2020
................................... Subscription required 2020
................................... Subscription required 2020
................................... Subscription required 2020
................................... Subscription required 2019
................................... Subscription required 2019
................................... Subscription required 2019
................................... Subscription required 2019
................................... Subscription required 2019
Corporate Presentation 2018
Management Discussion & Analysis 2018
Press Release 2018
Year-end Mineral Reserves 2018
Annual Report 2017
Management Discussion & Analysis 2017
Fact Sheet 2016
Management Discussion & Analysis 2016
Annual Report 2015
Annual Report 2014
Technical Report 2013
Subscription required - Subscription is required.

News:

NewsDate
IAMGOLD Announces Temporary Workforce Reduction at Its Westwood Gold Mine November 23, 2020
IAMGOLD Reports Seismic Event at Westwood Underground Mine November 2, 2020
IAMGOLD Reaffirms Long-Term Production Guidance for Westwood and Files NI 43-101 Technical Report August 5, 2020
IAMGOLD To Restart Westwood Gold Mine April 14, 2020
IAMGOLD Provides Update Following Provincial Directives Regarding COVID-19 March 24, 2020
IAMGOLD Announces Westwood Gold Mine Workforce Reduction March 19, 2019

Aerial view:

Subscription required - Subscription is required.

Terms of Use Privacy Policy © 2020 MDO Data Online Inc.