The Vancouver-based company based its decision on a positive preliminary economic assessment (PEA).
The study assessed the company's options for expanded mining and processing of the substantially increased indicated and inferred resources announced in October.
It found B2Gold would have few challenges lifting baseline capacity from 6Mtpa to 7.5Mtpa for the low capital outlay, since it would not require an additional ball mill or power generation capacity.
An optimised mine plan has more higher-grade ore being delivered to the bigger plant after expansion of the mining fleet.
The current mining fleet consists of four Caterpillar 6020B excavators, with haul trucks, drills and support equipment to match. Increased production will be achieved with the addition of two to four excavators with corresponding trucks, drills and support equipment. Large front-end loaders would also be included to maintain fleet flexibility.
Fekola could produce 550,000oz/y between 2020 and 2024 and 400,000oz/y on average between 2019-2030, B2Gold said.
The PEA outlines a US$500 million increase in Fekola's NPV, forecast life-of-mine pre-tax net cash flow of about $2.8 billion. The revised life of mine operating cash cost and AISC will be between $500-$700/oz.
B2Gold said it was also assessing various optimisation alternatives, including processing gold ore from its Anaconda project, north of Fekola; installing solar power at the Fekola premises; and in-pit crushing and conveying as a means to reduce operating costs and potentially implement tailings and waste co-disposal at the Fekola mine.
B2Gold said the process would continue through the June quarter of this year and would be incorporated into a revised Fekola LOM plan, slated for publication in the March quarter of next year.
Fekola, which poured first gold late in 2017, has an indicated mineral resource of 92.8Mt grading 1.92g/t containing 5.73Moz.