The Eagle’s Nest mine is a high-grade nickel-copper-platinum group element (PGE) deposit discovered by Noront in 2007. The mine is located in the McFaulds Lake project area in the Ring of Fire region of Northern Ontario, Canada.
A positive feasibility study for the Eagle’s Nest mine, which is Noront’s first project in the Ring of Fire region, was completed in 2012.
Noront is currently updating the 2012 feasibility study, which it expects to complete by the end of 2019.
Construction on the project is expected to start by early-2020 and production is anticipated to begin in 2023.
The mine is expected to produce up to 250,000t of nickel-bearing concentrate a year and is estimated to have an operational life of 11 years.
Geology and mineralisation
The Eagle’s Nest deposit is engulfed in an ultramafic sill complex with a total strike length of 16km and 1.5km thickness. The complex lies between a tonalite body and an overlying volcanic sequence and includes two discrete sills called the Double Eagle Intrusive complex and the Black Thor intrusive complex.
Both the sills hold ultramafic keel and a feeder dyke with Ni- Cu-PGE mineralisation.
The Double Eagle Complex hosts the Eagle’s Nest Ni-Cu-PGE deposit, which is located along the north-west margin of the host intrusion. The mineralisation comprises massive to net-textured and disseminated sulphide-bearing pyrrhotite-pentlandite-chalcopyrite.
Eagle’s Nest mine reserves
The mine currently contains more than 20 million tons (Mt) of measured, indicated and inferred resources with high-grade nickel mineralisation.
Proven reserves are estimated to be 5.264Mt grading 2.02% nickel, 1.04% copper, 1.01g/t of platinum, 3.45g/t of palladium and 0.19g/t of gold.
Probable reserves are estimated to be 5.867Mt grading 1.38% nickel, 0.72% copper, 0.78g/t of platinum, 2.76g/t of palladium and 0.18g/t of gold.
The Eagle’s Nest mine will employ blast hole stoping techniques to mine its nickel-copper-platinum-palladium mineralised pipe having a strike length of 200m and width of 60m.
The initial mining process will involve the use of explosives for the mining of aggregates and automated underground mining techniques. Tailings and paste tailings will be used to fill the voids and aggregate stopes.
The mill and concentrator of the Eagle’s Nest mine will be capable of processing 3,000t of ore a day. Conventional crushing, grinding, flotation and concentrate dewatering will be employed to produce a single concentrate.
Trucks will be used to transport the nickel-copper concentrate from the mine site to Savant Lake and further shipping will be done by rail to a smelter in Northern Ontario.
An on-site diesel-fired power plant will be built to supply power to electrical equipment, underground mine and other infrastructure such as camp facilities and airstrip.
Water for the underground facilities will be provided by a common bore hole drilled in the portal area.
Contractors involved with Eagle’s Nest mine development
Micon International conducted the 2012 feasibility study for the Eagle’s Nest project. Cementation is responsible for the underground mine development and concrete formations, while Kiewit is responsible for the construction of access road to the mine site.
Nuna Logistics was contracted for the development of site roads and transportation logistics.
ATCO Structures and Logistics is responsible for the construction of permanent camp and associated infrastructure.
AECON Group is responsible for the mechanical, electrical and instrumentation installation. Outotec was preferred for the design and delivery of the processing plant equipment, while Atlas Copco was contracted to deliver the underground and processing equipment.
ABB is involved in the design and supply of electrification, automation and communication systems. Penguin Automated Projects was contracted for the mine design, scheduling, design of the back-fill facility, ventilation, and cost estimation.
Tetra Tech was contracted for the power plant infrastructure and utilities. SGS-Mineral Services was contracted to perform the mineral extraction tests and assistance with defining the process flowsheet.
Golder Associate was contracted for geotechnical drilling and assessment. Knight Piésold Consulting prepared the environmental baseline studies, whereas Ausenco PSI provided designs for the proposed concentrate pipeline.