Australia’s Resolute Mining, listed on the ASX, reported in December the successful commencement of sublevel cave ore production from the new Syama Underground Mine in Mali, West Africa.
The extraction of first ore from the southern end of the 1105 level of the Syama sublevel cave marks the greatly anticipated beginning of the main caving operation at Syama and the achievement of a major milestone for the company.
The twin decline of the Syama Underground Mine. Seen in the photo are (from left) Issa Diarra, Syama Communications Specialist; John Welborn, MD and CEO of Resolute; and Peter Beilby , COO (photo: Resolute).
“The successful development of the Syama Underground Mine represents a pivotal moment in the long history of Resolute,” commented Resolute’s Managing Director and Chief Executive Officer, John Welborn, who was on-site at Syama for the commencement of ore production from the sublevel cave.
“Syama will be the world’s first purpose-built, fully automated sublevel cave gold mine,” he said. “It is a world-class, long-life, low-cost asset that will deliver long-term benefits to our shareholders, stakeholders, and local Mali communities for years to come.
“Syama will be the most sophisticated and advanced gold mine in Africa. Our investment in exploration, infrastructure, technology, power and innovation at Syama has transformed a world class orebody into a world class mine. Resolute has an ambition to be a leader in sustainable and responsible economic growth in Africa. We recently announced plans to build a new 40 MW Syama Solar Hybrid Power Plant which will deliver an expected 40 % savings on power costs and is expected to be the world’s largest mine-based, off-grid fully integrated independent solar hybrid power plant.
“The commissioning of Project 85, a series of sulphide processing plant upgrades, will enable us to achieve improved recoveries from high-grade ore sourced from the new sublevel cave,” Welborn continued.
“The combination of mine automation, improved recoveries, and lower cost power has the potential to increase Syama site production to 300 000 ounces of gold per annum and reduce Life-of-Mine All-In Sustaining Costs to below US$750 per ounce.
“The Syama Underground Mine is an achievement that builds Resolute’s African development expertise demonstrated in earlier successes at Obotan and Golden Pride. The new mine also builds on the company’s underground technical achievements demonstrated in pioneering the sublevel shrinkage mining method at the Mount Wright Underground Mine in Ravenswood, Queensland.”
Sublevel caving is an advanced and highly efficient low-cost bulk underground mining method that provides early access to ore. Mining commences at the top of the deposit and develops downwards. Ore is mined from sublevels spaced at regular intervals throughout the deposit. A series of ring patterns are drilled and blasted from each sublevel, and broken ore is extracted out after each blast. Sublevel caving comprises a series of repetitive activities and is ideally suited to automation.
Syama is well suited to the sublevel caving mining method because of its scale, width, orientation, and uniformity of grade. Unlike other bottom-up caving methods (block cave, panel cave), sublevel cave mining is a top-down method and therefore does not require large initial investments in mining infrastructure prior to commencement.
The Syama sublevel cave commenced on the 1105 level with the firing of the first production ring. Production drilling continues in the 1105, 1130 and 1200 levels as the underground mine advances towards the targeted full production rate of 2,4 Mt/a.