Envisages a mining rate to cater for the delivery of 300,000 tonnes of +6.75 mm material per year to produce ferrosilicon (FeSi) at a furnace facility in Southland. At steady state, the FeSi produced will be approximately 157,500 tonnes per annum (tpa).
The Canadian Metals Inc. Langis ferrosilicon project operations were deemed an appropriate comparative example to that of PHP. Obvious differences occur, for example hard rock quartzite mining at Langis requires blasting and crushing and mining using conventional mine equipment (i.e. trucks, excavator, graders, drill rigs, bulldozer, service vehicles) while at PHP a free dig with tractor pull scrapers will predominate the mining methodology.
Indicated Resources and a thirty percent proportion of Inferred Resources are assumed in Scenario 2. For Scenario 2 a doubling of the factors (i.e. equipment, costs, rehabilitation, and infrastructure) used for scenario 1 was applied. Clearly this is a conservative approach but was applied based on the strict rule of expansion based on modular repetition. For an example during the Feasibility stage it might be found that the Bluff harbour cannot cater for FeSi production but may be suitable for Scenario 1 raw product output only. Scenario 2 FeSi envisaged production could still be implemented with a FeSi plant being located, say near the harbour at Dunedin, Otago.