Orsu Metals, a London-based junior company, has reported the results of a definitive feasibility study of its 94.75%-owned Karchiga volcanogenic massive sulphide copper project in the Kurchumskiy district of East Kazakhstan province, Kazakhstan. Production is estimated 13,000 mt/y of copper from open-pit mining of sulphide and oxide ores over a mine life of 11.5 years.
A sulphide concentrator would process approximately 750,000 mt/y of ore, using relatively fine grinding and selective sulphide flotation to produce a 27.9% copper concentrate. First production is planned for the fourth quarter of 2013.
To reduce initial capital expenditures, construction of the SX/EW plant would be delayed until after payback of initial capital expenditures required to start up the sulphide operation. Oxide ores would be processed by heap leaching and solvent extraction/electrowinning (SX/EW) over a period of 4.5 years beginning in 2018 at a processing rate of 360,000 mt/y.
Initial capital expenditures to start up the sulphide operation are estimated at $115 million. Total capital project expenditures, including the SX/EW plant, are estimated at $147 million. Life-of-mine, pre-tax cash operating costs are estimated at $1.47/lb of copper.
SRK Consulting (UK) Ltd. was the lead contractor in preparation of the Karchiga feasibility study. The study considers a probable mineral reserve of 8.5 million mt of sulphides in two pits containing 145,200 mt of copper at an average grade of 1.71% copper and 1.5 million mt of oxides in a third pit containing 21,400 mt of copper at an average grade of 1.43% copper.
The environmental and social impact assessment study for the Karchiga project was completed by Wardell Armstrong International in January 2012. Orsu Metals expects to receive the necessary construction permitting approvals from the Kazakh authorities by the middle of 2012.
