A 22-year mine life, with potential to increase by expanding resource, is forecast for GreenRoc Mining’s graphite project at Amitsoq in southern Greenland.
ECONOMICS
SLR Consulting Ltd’s NI 43-101 preliminary economic assessment (PEA) includes average annual production of 77,000t of concentrate at a minimum 94% grade.
The mine plan assumes mining from only the lower graphite layer, leaving “considerable resources” from the upper graphite layer for future expansion of production or extension to the mine’s life.
GreenRoc said that Amitsoq would have a four-year payback period on capital from the start of production.
Initial capital expenditure is US$131 million, inclusive of 25% contingency, and average operating costs are $121 per tonne of milled ore.
Average net revenue is an annual $89.8m throughout the life of the mine with total gross revenue of $2.1 billion and total undiscounted net pre-tax cash flow of $794.7m.
GreenRoc added that the PEA’s “strong economic results” independently validated the project’s potential to become a “globally significant” producer of graphite concentrate.
The company also continues to develop processing capabilities to improve future graphite concentrate production into anode material for electric vehicle batteries, to add “substantially” to Amitsoq’s economics.
TAILINGS
Chief executive Stefan Bernstein said that the mine plan was relatively straightforward because of Amitsoq’s simple ore body geometry.
“All of the on-site processing equipment is based on the use of standard and proven techniques, but with potential upside through the use of some new, and more efficient, processing technologies that we are currently exploring.
“About 75% of the mined ore in the PEA is sourced in the measured and indicated category and, given the simple ore body geometry, we are confident that the remaining ca. 25% can be upgraded into the higher confidence resource categories.”
GreenRoc plans to use a drift and fill mining method which, with the “exceptionally high grades” of Amitsoq ore, will see as much as 86% of the tailings used as backfill and just 14% going into a tailing storage facility.
“This is excellent news as it will minimise the environmental impact of the mine, whilst also saving the cost of transporting tailings,” added Mr Bernstein.
“While the PEA is based on the use of conventional diesel-generated power, we are looking into a variety of emission-free energy solutions to replace the diesel-generated power plants as soon as that is feasible.”