Heron Resources has started commissioning at the Woodlawn zinc-copper-lead project in New South Wales, Australia, paving the way for first production in the March quarter.
The ASX-listed company said the owners and contractor commissioning teams for the combined underground mine and tailing retreatment project were now in place, while the hydraulic tailings retreatment preparations had started with infrastructure energised and water testing underway.
In addition, the process plant commissioning had started with testing of the plant control circuits. Heron noted commissioning of the water treatment plant was well advanced.
Heron said: “The hydraulic mining operation, alongside the underground operations that commenced in September 2018, will provide a second ore source to be processed through the new processing plant.”
The hydraulic mining operation covers the recently arrived hydraulic monitors and the associated high-pressure water, reclaim and slurry transfer pumps, with commissioning activities involving the functional testing of equipment in the circuit (including the commissioning of the trash screen and transfer pumps at the transfer station).
Commissioning is expected to ramp up over a four-to-eight-week period and will include the hydraulic excavation of the main channels in preparation for ore commissioning of the process plant with progression to full production rates, Heron said.
“The EPC (engineering, procurement and construction) contractor has commenced its commissioning activities in the main process plant, with low voltage and control circuit testing underway,” Heron said.
“These activities (dry, wet and ore commissioning) will continue through stages into quarter one, 2019, when first production is expected. As at the end of November, the EPC contractor reported commissioning at 5% complete.”
“In conjunction with the commissioning preparation-related activities that have been occurring over the past few months, the Woodlawn site team have also been progressing production readiness preparation.”
This has led to the first fill consumables orders being placed, in addition to the operation being bulked out with enough personnel for initial commissioning.
Woodlawn is envisaged as a 1.5 Mt/y operation able to produce 40,000 t/y of zinc, 10,000 t/y of copper and 12,000 t/y of lead at steady-state production over a 9.3-year mine life. This is based on a reserve base of 2.8 Mt at 14% ZnEq from underground and 9.5 Mt at 6% ZnEq from reprocessed tailings.
Underground mining, being carried out by contractor Pybar, kicked off in October.