The shaft was completed prior to the underground workings reaching the bottom of the shaft. This ensured the critical path of the mine was not impacted by the installation of the shaft, and the shaft is ready for operation when required by Dendrobium.
Blind boring methods used by Ardent Underground to construct shafts use reverse circulation and do not require the mine to deal with the cuttings. Ardent’s drilling capabilities are 1.5m diameter to 1500m deep and seven metres in diameter up to 700m deep.
The drill rig used for the Dendrobium Mine project was custom-built using innovative technology, Ardent said.
“The rig is powered by an electrical AC variable frequency drive which allows the operator to run the machine by remote control. The drill rates averaged ten metres per day, with runs up to one metre per hour. The remote drilling and lining processes used by Ardent Underground are part of the company’s commitment to safety,” Ardent said.
No personnel were required to enter the shaft during any phase of the shaft construction. The Dendrobium Ventilation Shaft No. 1 project was completed with a lost Time Incident Frequency Rate of zero.
