MINING IN CHILE — Zaldivar project on schedule

Construction of the Zaldivar copper deposit in northern Chile is expected to be completed in the second half of 1995.

Partners Placer Dome (TSE) and Outokumpu Copper Resources project the capital cost of the 41,000-tonne-per-day heap-leach operation at US$600 million.

During the mine’s 17-year life, additional expenditures of US$143 million will be required to expand heap-leach facilities and purchase open-pit equipment.

Placer Dome bought its half interest in Zaldivar from Outokumpu in 1992 for US$100 million and agreed also to provide up to US$400 million in loan financing for the project.

Proven and probable heap-leachable reserves are estimated at 246 million tonnes grading 1.02% copper plus 69.3 million tonnes of dump-leach ore grading 0.41% copper. The overall stripping ratio is 2.75-to-1. The deposit will be worked in a series of six pits during the 17 years, with leaching extending the project life to 19 years.

Ore processing, prior to stacking on leach pads, will include primary, secondary and tertiary crushing.

Uncrushed, run-of-mine, dump-leach ore will be transported to separate dump leach pads which, depending on economic circumstances, are expected to come on-stream in the eighth year of operations.

Zaldivar should produce about 125,000 tonnes copper (275 million lb.) per year at an estimated cash cost of US$1,080 per tonne (US49 cents per lb.). It is estimated that, during the life of the mine, sulphide heap-leach ore will constitute 49% of copper production, oxide ore 45% and dump-leach ore 6%.