Aureus Mining Inc, the TSX and AIM listed West African gold producer, has temporarily suspended plant operations at its New Liberty Gold Mine (NLGM) in Liberia. NLGM, Liberia’s first commercial scale gold mine, was commissioned last year and is designed to produce an average of 120 koz/a over the first six years of its life. The first gold pour took place in May 2015 and commercial production was declared earlier this year.
The processing plant of the New Liberty Gold Mine in Liberia (photo: Aureus Mining).
In a statement issued on 10 May, Aureus says the detoxification circuit has not been operating to original design specifications resulting in higher concentrations of cyanide WAD (weak acid dissociated cyanide) in the process effluent. “The company had therefore been operating with process water in a closed circuit (zero discharge from the Tailings Storage Facility (TSF)). Recent heavy rainfall inadvertently resulted in a small overflow of effluent from the TSF onto the wetlands area (within the mining lease area). Aureus is conducting remediation work to rectify the issues in the detoxification circuit and to manage future water discharge from the TSF in order for operations to recommence in the near future.”
Aureus says its investigations to date indicate that there has been no adverse impact on any human settlement as the discharge took place within the mining lease and some 5 km from the nearest settlement. However, further investigations are in progress and, in view of this leakage, a decision was taken to suspend processing operations on 7 May 2016.
SRK Consulting (UK) are on site at New Liberty assisting Aureus engineering staff with the evaluation of the adjustments to be made to the waste neutralisation section of the detoxification circuit and the management of water discharge from the TSF in order for processing operations at New Liberty to recommence.
Aureus says that during this temporary suspension of processing operations, it is taking the opportunity to effect a mill reline, undertake other preventative engineering maintenance and repairs (all of which were previously scheduled) as well as modifications to the detox circuit proposed by the expert consultants. Furthermore, mining operations are continuing at New Liberty in order to build up ore stockpiles and undertake waste stripping.
