The Éléonore gold project is located in the mineral-rich James Bay region of Quebec, Canada, one of the ten biggest gold producing countries in the world. The project was initially owned by Goldcorp until it was acquired by Newmont Mining in April 2019.
The project was developed with a $1.8bn investment and is expected to have a mine life of 15 years. The first gold from the Éléonore mine was poured in October 2014 and commercial production began in April 2015.
The Elenore Gold project currently produces 246,000oz of gold per annum.
Éléonore mine geology and reserves
Located approximately 350km north of Matagami Town, the Éléonore gold project forms part of the clastic sediment-hosted Roberto gold deposit, which features two major auriferous zones namely, Roberto and East Roberto under the waters of the Opinaca reservoir.
The mining property is extended more than 19,274ha within the contact zone between the La Grande and Opinaca sub-provinces and comprises 369 contiguous claims. Goldcorp acquired the project from Virginia Gold Mines in 2005.
Gold mineralisation at Éléonore is intersected to a vertical depth of 1,400m and is mostly found within the stockworks of quartz-tourmaline-arsenopyrite veins and veinlets.
The proven and probable mineral reserves at the Eleonore mine as of December 2020 were estimated at 7.8Mt grading 5.0g/t of gold containing 1.26Moz of gold.
Mining and processing of ore at Éléonore gold mine
A combination of open-stoping and longitudinal retreat stoping methods is employed for the underground mining at Éléonore.
The mining plan includes initial production from the upper portions of the Roberto deposit using the Gaumond / ventilation shaft. Deeper gold resources will be accessed by a production shaft running as deep as 1,500m below the surface, starting from 2018.
Using 55t trucks, ore is hauled to the loading stations located at 650m-deep before being transported to the surface via the Gaumond / ventilation shaft.
The operation also includes a 3,500 tonnes per day (tpd) processing plant, which is expected to be expanded to process 7,000tpd by 2018.
The process flow at the plant includes three-stage crushing, a single stage of ball mill grinding, gravity concentration, sulphides flotation, cyanide leaching and gold production in a carbon-in-pulp (CIP) circuit.
Ore from the surface bin is conveyed to the primary feed hopper via conveyors and then fed to the primary jaw crusher, secondary and tertiary crushers. The crushed material is conveyed to a ball mill, which operates in a closed circuit with a cyclone pack.
The ore material then passes through a floatation circuit, where frother is added to produce a stable froth and recover 95% of gold sulphide. The sulphide concentrate is transferred to the flotation concentrate cyanidation circuit.
The concentrate is then leached and the slurry transferred to the concentrate CIP circuit for adsorption. The flotation concentrate stream is then pumped to the concentrate CIP thickener through a carbon safety screen. The gold concentrate finally undergoes an electro-winning process to produce gold doré bars.
Infrastructure facilities at Éléonore mine
Power supply for the mining operations and processing plant is provided from the Éléonore main 120/25kV substation.
Drinking water supply for the campsite and industrial area is sourced from four wells located 1.2km north-east of the project campsite.
Other major infrastructure facilities for the gold mining project include two shafts, a surface ramp, a waste rock storage dump, tailings storage facilities, a process plant, offices, and a permanent camp comprising 400 rooms.
SNC-Lavalin was awarded a contract in January 2013 to provide engineering, procurement and construction management (EPCM) and project management services for the Éléonore project.
MIPAC Process Automation Canada delivered IsaControl instrumentation and automated control system for the grinding circuit at the Éléonore processing plant.
UK-based DavyMarkham was awarded the contract to supply two double-drum hoists for the underground gold mining project. ABB Montreal was subcontracted by DavyMarkham for the supply of electrical drive equipment for these two hoists.
Howden was contracted to design and implement a ventilation control system to optimise the supply of fresh air to the mine.