SINCE commencing operations in mid-October at the Derewo River Gold Project of West Wits Mining in Papua Province, site management has focused on developing the most efficient circuit for mining the 81 Creek alluvial gravels. This has involved testing the optimum set up of the sluice boxes to maximise efficiency, testing processing systems such as water cannon and venturis, and training local community members to operate the circuit.
As a result management has developed a comprehensive practical understanding of the specific issues involved in mining the area. It is evident that mining this gravel sequence will require the employment of various operational methods to deliver optimal recoveries.
For example, a water cannon is proving efficient at moving the gravels but the many in situ boulders require deployment of heavy equipment to clear a path. In addition the basement potholes, which tend to be higher in grade, are not amenable to mining through either of these mechanical methods and will need to be cleared out manually.
Thus far, this trial and commissioning phase has been conducted in the lower part of the 81 Creek where extensive artisanal mining has been undertaken for up to 10 years. These low grade gravels were initially targeted as they allowed management to gain confidence in the circuit without risking loss of higher grade gravels before moving to full production.
The first stage of full-scale mining is planned to commence at a location higher up the creek which should permit access to thicker and less mined gravels. The gravels are about 12 metres thick in this area and access points are dictated by the basement profile and topography.
After operations were closed for a short Christmas break, commencement of full mining has been scheduled for the week beginning January 4 preceded by a planned feast ceremony with the local community to mark the start of full operations.
Whilst operations have proceeded without interference a large number of illegal miners are operating in close proximity. These people continue to illegally remove gold and their presence constitutes an ongoing threat to stability and security. West Wits’ new Indonesian partner for the venture PT Intan Angliasa Aviation is continuing efforts to procure removal of the illegal miners but is yet to define a clear timeline to achieve that goal. The pleasing progress at Derewo must be tempered with caution until all unauthorised persons have been removed.