Aureus Mining temporarily suspended processing operations at its New Liberty gold mine in Liberia in early May after experiencing problems with the detoxification circuit in the plant, which had not been operating to original design specifications- resulting in higher concentrations of cyanide WAD (weak acid dissociated cyanide) in the process effluent.
Having restarted processing operations at New Liberty at the end of June following approval from the Republic of Liberia’s Ministry of Lands, Mines and Energy (MLME) to do so, Aureus spent time testing a number of plant modifications which were undertaken during the shutdown period.
Since the restart of processing operations, the company has experienced periods of unscheduled plant downtime as it works to resolve processing plant performance issues, testing and further optimisation activities.
The company will apply to the MLME for approval of the full and continued operation of the processing plant once it has achieved steady state operations for a continuous period of 60 days.
Since the recommencement of processing operations, gold shipments have resumed with the company pouring and shipping approximately 3 500 oz of gold.
Despite the slow start of operations following the shutdown, the New Liberty mine produced 8 274 oz for the quarter ended 30 June 2016, prior to the suspension of gold processing operations.
Aureus also sold 11 731 oz of gold during the second quarter, delivering revenues of US$14.7 million.
Throughout the period of suspended processing operations, Mining operations continued at New Liberty, with a focus on exposing further fresh ore within the Kinjor and Larjor pits and establishing sumps allowing for continuing mining operations throughout the wet season. ROM stockpiles currently stand at approximately 201 367 t of fresh ore at a grade of 3.24 g/t and oxide and transitional stockpiles stand at 91 719 t at a grade of 1.46 g/t.
However, mining operations continue to be hampered by low equipment availability, with a consequential adverse effect on unit mining cost.
As a result, Aureus is currently undertaking a review of the options to remedy the situation, while also undertaking a full supply chain review to identify opportunities for efficiency improvements.