Underground Mining, Copper Mining Australia, Copper Mine

Birla Nifty

Copper Production Operations

Birla Nifty copper mine is located in the Great Sandy Desert Region of the East Pilbara in Western Australia, approximately 1,250 km north of Perth and 350 km east of Port Hedland.

The Nifty operation comprises of an historical open pit oxide mine and an underground sulphide mine with an associated concentrator. Site infrastructure (powerhouse, camp, airfield, tailings storage facility) supports the sulphide operations. A concentrate storage facility is located at Port Hedland where the concentrate is shipped to overseas customer.

The Nifty Sulphide deposit mines chalcopyrite ore treated by standard flotation for production of copper concentrate.

The Western Australian copper mine has a capacity of 2.3 mtpa and the concentrator plant has a capacity of 2.5 mtpa. Concentrate produced is trucked to Port Hedland for shipping to Hindalco Copper’s Dahej smelting and refining facility in India.

Mining

Underground mining is performed by Birla Nifty, using modern diesel or electro-hydraulic equipment of large capacity. Underground mining is currently carried out using open stoping methods and backfill. This is a bulk mining method where stopes (25m wide, 25 to 50m long and 40 to 60m high) are drilled and blasted, and copper ore is loaded and hauled into to an underground crusher and conveying system. The conveying system transports the copper ore to the surface for processing by conventional flotation techniques (an example is shown in the figure above).

The ore is drilled with electro-hydraulic rigs prior to blasting. Broken ore is loaded using load-haul-dump machines into 50 t capacity trucks for transport to the underground crusher, where it is conveyed to the mill, surface ROM pad or stockpile.

The underground mining method at Nifty is considered a low cost method as opposed to other underground selective mining methods due to the inherent economies of scale and the use of conveyors to transport ore to the surface as opposed to trucking. The backfilling of mining voids allows for high recovery of resources and savings in lifting tailings dams. The equipment used in underground mining is supplied by various manufacturers like Caterpillar and Sandvik etc.

Processing

Processing of the sulphide copper ore extracted from underground is by conventional comminution, grinding and flotation, to produce a concentrate that is then filtered and sold as concentrate.

Copper Production

The Nifty copper operation is a fly in–fly out operation with access provided via a sealed airstrip on site, serviced regularly by flights from Perth. The mine is also accessed by bitumen road from Port Hedland to the Woodie Woodie mine, only the final 45 km of road is unsealed. Copper in concentrate is trucked to Port Hedland (distance from Nifty approximately 350 KM) and then shipped to Hindalco Copper’s Dahej copper smelting and refining facility in India.

The mine facilities are well supported by modern and efficient infrastructure and services, with significant upgrades and extensions made to village facilities, workshops, power reticulation and offices constructed under the Nifty Sulphide Operation development.

The main power source is a 21 mW GE dual fuel gas/diesel turbine, with back-up of 5.4 mW solar centaur turbines and 3.5 mW Caterpillar diesel generators. A 46 km spur gas pipeline, owned and operated by Gas Transmissions of Australia Pty Ltd, has been constructed from the Port Hedland to Telfer and is the pipeline to the Nifty Western Australian copper mine. Gas is sourced under contract from Apache Northwest Pty Ltd.

The Nifty copper operation uses groundwater sourced from mine dewatering. Mine water is reticulated from the largest source, the underground mine, to the Fines Dam where suspended solids are settled. Once clarified, the mine water is pumped to either the sulphide concentrator or Raw Water Dam (RWD) for distribution elsewhere on site. In addition to the mine dewatering source, groundwater derived from the East Nifty Borefield is pumped to the RWD or directly to the Reverse Osmosis (RO) plant for desalination.

Copper Resources and Reserves

Nifty ore reserves and mineral resources as on 31 March 2012 are shown below.

Notes

1. The information in this statement for the Nifty Copper Operations underground Ore Reserve is based on information compiled by Mr Brad Watson under the direct supervision of Mr David Lee who is a Fellow of the Australasian Institute of Mining and Metallurgy and a full time employee of AMC Consultants Pty Ltd. Mr Lee has sufficient relevant experience to be a Competent Person as defined in the JORC Code. Mr Lee consents to the inclusion of this information in the form and context in which it appears
2. Totals may not add due to rounding.
3. Mineral resources are inclusive of ore reserves, but exclude recoverable inventory under leach.

Background

Open pit mining operations ceased in June 2006 and heap leaching operations ceased in January 2009.

Oxide copper was first discovered at Nifty in 1981 by WMC Limited ("WMC"). Drilling of the oxide resource ultimately led to the discovery of the deep sulphide resource in 1983. WMC commenced an open pit, heap leach, SX-EW operation on the relatively high grade part of the oxide mineralisation in 1993. In 1998, the Nifty operation was purchased by Straits Resources Limited ("Straits Resources"), from which Aditya Birla Minerals acquired the operation and surrounding exploration tenements in March 2003. Before acquisition of Nifty Operations a detailed due diligence was undertaken by Aditya Birla Minerals.

Due diligence of Nifty operations was conducted by various experts in their respective fields:

• Technical due diligence by SRK Consulting
• Commercial due diligence was done by Cutfield Freeman & Co Ltd
• Financial due diligence was done by Ernst and Young and
• Legal due diligence by Minter Ellison
• Environmental audit by R.W. Corkery & Co Pty Ltd.

The due diligence process highlighted significant values in the Nifty underground mine. There were no material adverse findings. Subsequent to acquisition, following the completion of a positive feasibility study, underground development was commenced in January 2004 to exploit the sulphide resource via an exploration decline from the open pit. First sulphide ore was intersected in February 2005. Construction of the concentrator commenced in October 2004, with first concentrate being produced in March 2006. Other plants previously under construction include the paste fill plant, which was completed in August 2009.

Copper Opportunities

Underground mining and copper production at the Birla Nifty copper mine in WA provided opportunities for further copper exploration and development. This includes the extension of mine life via extending resource base in existing ore body and converting more resource in to reserve category and finding another ore body through exploration and evaluation.

To learn more about our credible copper production, copper exploration , copper mine in WA and QLD, copper mining, underground mining or copper investment opportunities, copper operations, contact Aditya Birla Minerals.