PERTH (miningweekly.com) – Indonesia-focused Sumatra Copper & Gold has restarted ore production from its Berenai openpit operation, at its Tembang gold/silver mine, but has warned of lower production during the June quarter.
The company in February warned that ore production at Berenai would be delayed after the original feasibility study on the openpit operation was found to be inaccurate, and included portions of backfilled and rilled material.
The waste material, which comprised mainly thick mud, proved difficult to remove, Sumatra said, particularly during the wet season.
Some 12 000 gold equivalent ounces will be mined below the current openpit floor during Stage 2 of the operation, with a further 5 600 gold equivalent ounces to be mined in Stage 3.
Sumatra told shareholders that as a result of the delay in ore production at Berenai, the June quarter production was expected to be significantly lower than planned, with the full-year guidance also being reduced by 5 000 oz, to between 40 000 oz and 50 000 oz.
Meanwhile, the Belinau underground mine has been transitioning from interim bench cut and fill ore drives to shrinkage stoping, with underground ore production scheduled to be low during this period.
Sumatra pointed out that the combined impact of limited underground and openpit production had placed significant pressure on working capital during April and May, which resulted in supply delays for key underground equipment and infrastructure.
However, the required equipment has now been ordered, and stoping is planned to start in the near future.