PERTH (miningweekly.com) – Additional mine development required to facilitate the restart of operations at the Cascavel mine, in Brazil, will start in April, ASX-listed Orinoco Gold has reported, with the initial development to be focused on adding new access ramps and new development headings to allow for larger-scale equipment to be deployed within the mine.
Orinoco told shareholders on Thursday that the strategy to restart operations at Cascavel had now been fully developed, and detailed mine development planning was nearing completion.
Following the restart of development in early April, the mine plan to deliver some 80 000 t/y of ore to the processing plant, double the initially planned mine capacity, would be finalised to facilitate ongoing mine development and to allow selected modified mining methods to be trialled.
Development will continue to be undertaken within the known mineralised zone at Cascavel, with Orinoco noting that while this material would be processed through the plant along with production material resulting from trial mining activities, deliveries of scheduled production ore to the mill would only start late in the third quarter of this year.
Meanwhile, the final results from the most recent set of metallurgical tests will be received in late March, and will allow Orinoco to finalise the design of any required mill improvements.
Orinoco noted that additional grinding capacity would likely be sourced for the processing circuit to improve gold liberation and recoveries; however, the type and sizing of the grinding capacity, and the decision on whether it would operate in conjunction with the existing tertiary crusher or as a replacement to the existing crusher, will only be taken once the results from the metallurgical testwork have been received.
The existing plant, in the meantime, remains capable of processing stockpiled and future development material in batches while the plant undergoes the minor proposed modifications.
An independent technical review in December 2016 advised a restart of the Cascavel mine, concluding that the mine and plant issues experienced during the start-up were common commissioning problems readily fixed.
Orinoco had suspended operations at Cascavel in October 2016, after the mine failed to meet production expectations.