Image: Gosowong Gold Extension Project: EPCM project delivered in logistically challenging location

Minerals & Metals1 min read

Gosowong Gold Extension Project: EPCM project delivered in logistically challenging location

Halmahera Island, Indonesia
Newcrest Mining Limited
2008 - 2010

Ausenco provided EPCM services to Newcrest Mining Limited to expand throughput for its Gosowong gold process plant on Halmahera Island in eastern Indonesia.

This operation is managed by PT Nusa Halmahera Minerals (PT NHM), a joint venture between Newcrest Mining Limited (82.5%) and PT Aneka Tambang (17.5%).

In March 2008, Ausenco was awarded the feasibility study for the Gosowong Extension Project which established the processing plant and infrastructure required to increase plant throughput from a baseline of 35 t/h to a targeted 45 t/h.

In August 2008, following the purchase of a used vertimill ex Williams Hemlo Mine located in Ontario, Canada, Ausenco was engaged as the EPCM contractor to complete the upgrade to 45 t/h. This is also referred to as the “Vertimill” project with major equipment including a Metso Vertimill, Falcon Concentrator and a Gekko intensive leach reactor.

In December 2008, Ausenco was awarded a contract to further increase the plant throughput to 65 t/h. The EPCM scope included significant HV infrastructure upgrade works, surface infrastructure and process plant upgrades. Key major equipment includes a Wobbler Feeder, 1 MW SSSAG Mill, Pre-Leach Thickener, a 2nd CCD Train, various filters and an 11 MW Power Station.


  • Commissioning of the Vertimill project completed by end of May 2009
  • Completion of the HV Infrastructure upgrade works in July 2010
  • Power station completion and tie-in to the main power grid on 22 October 2010.

Ausenco worked closely with in-country suppliers and contractors to maximise local participation which ensured compliance with site policies regarding local employment and consequently enabled savings to be passed on to our client.

  • 1 MillionLTIF hours achieved during August 2010
  • 65 t/hCommissioning of process plant extension completed in early September 2010