Summary

Deposit type

• Skarn
• Vein / narrow vein
• Porphyry
• Volcanic hosted

Summary:

Fold Belt of New South Wales. The district comprises four porphyry deposits, Ridgeway, Cadia Extended (Cadia Quarry), Cadia Hill and Cadia East, and two related iron-skarn deposits, Big Cadia and Little Cadia.

The mineralisation within the Project area occurs within a 6 km-long west–northwestoriented corridor.

Six mineralisation styles are known in the district:
• Cadia Hill: Intrusion and volcanic-hosted, sheeted quartz vein mineralisation;
• Cadia East: Volcanic-hosted, disseminated and sheeted quartz vein mineralisation;
• Cadia Far East: Volcanic and intrusion hosted mainly sheeted quartz vein mineralisation;
• Cadia Quarry: intrusion hosted mainly sheeted quartz vein mineralisation;
• Ridgeway: intrusion and volcanic hosted quartz stockwork vein mineralisation;
• Big Cadia, Little Cadia: iron-rich skarns.

Mineralisation in the porphyry deposits occurs as sheeted and stockwork quartz–sulphide veins, and locally as broadly stratabound disseminated mineralisation (C

Mining Methods

• Block caving
• Sub-level caving
• Panel caving

Summary:

ently, the pit has been used for tailings storage. The Ridgeway Deeps and Ridgeway underground mine was also placed into care and maintenance by 2018.

Production mining is an underground panel cave mining from Cadia East with underground crushing and conveyor to surface. Mine development at Cadia East commenced in 2012 with commercial production following in 2013 and is now a very large-scale underground mining operation adjacent to the Cadia Hill open pit.

Current mining operations in production at Cadia East consist of three mature panel caves and two developing panel caves.

Caves in production
PC1-1, PC2-1 (PC2-West), and PC2-2 (PC2-East) are in production and have been for some time.

Cadia East is accessed via two declines, the main access decline, and the conveyor decline.

Extracting ore by panel caving involves a series of steps:
* development of an access decline to the bottom of the orebody, an undercut level (to blast the ore), an extraction level (to remove the ore) and drawbells (through which ore gravitates from the undercut level to the extraction level);
* undercutting a block of ore to induce caving of the rock mass (which results in “fragmentation” or breaking of the ore);
* removal of the broken ore from the extraction level via load-haul-dump fleet to underground crushing stations; and
* transportation of the crushed ore via conveyor to a coarse ore stockpile at surface. Waste rock is hauled to the surface via the access decline.

The mining method involves inducing caving of the rock mass by undercutting a block of ore. Mining proceeds by progressively advancing an undercut level beneath the block of ore. Above the undercut level, the overlying rocks are pre-conditioned by blasting and/or hydraulic fracturing resulting in consistent progression of the fracturing of the caving ore block as it is mined.

Following pre-conditioning, broken rock is removed through an extraction level, which is developed below the undercut level. The extraction level is connected to the undercut level by draw-bells that open into draw-points from which the broken rock is removed. Load-haul-dump (LHD) units load the broken ore at the draw-point and dump the material into underground crushing stations.

At each crushing station, ore is tipped into a coarse ore bin, which then feeds the crusher. Crushed rock is then fed to a surge-bin which regulates the flow of crushed rock onto collection conveyor belts. The collection belts then feed crushed rock onto the main trunk belt system, which transports ore to the surface at a rate of between 4,600 to 5,150 tonnes per hour. The main trunk belt extends approximately 7,500 m to the surface, depositing material on the concentrator coarse ore stockpile. The coarse ore is then gravity fed into the surface ore processing system.

Waste rock is removed from the underground workings by truck via the decline and dumped at the South Waste Rock Facility.

PC1-1 is the original caving

Comminution

Crushers and Mills

Summary:

and now primarily used for surface stockpile reclaim;
• Coarse ore stockpile (COS) to a live capacity of 40,000 t and subsequent reclaim facilities;
• Distribution bin and double-deck vibrating screens for feed size preparation;
• Secondary crushing, treating screen oversize, using MP1000 cone crushers;
• High pressure grinding rolls (HPGR) unit treating screen undersize prior to the SAG mill;
• Primary open circuit milling in a single 40-ft SAG mill fitted with a 20 MW motor. The motor will be upgraded to 22 MW. Oversize pebbles from the SAG mill are returned to the distribution bin;
• Secondary milling in three ball mills, with the two original mills fitted with 8.7 MW motors, and a more recently installed third ball mill with a 16 MW motor. The mills are in closed circuit with cyclone classification for a target grind size of P80 of 150–190 µm.

Concentrator 2:

• Reclaim and conveying system to transfer ore from Concentrator 1 COS to Concentrator 2 facilities;
• Secondary and tertiary crushing using MP800 cone crushers and open circuit prescreening;
• Dedicated coarse (crushed) ore stockpile (COS) and apron feeder reclaim facilities;
• Primary open circuit milling in a single SAG mill fitted with a 7.5 MW motor;
• Secondary milling using a 7.5 MW ball mill and parallel Vertimill VTM1250, in closed circuit with classifying cyclones.
• Tertiary milling using a Vertimill VTM 3000.

Processing

• Jameson Cell Flotation
• Centrifugal concentrator
• Gravity separation
• Smelting
• Flotation

Summary:

ncluding operational improvements, over the years. The processing plant infrastructure includes high-pressure grinding rolls, SAG mills, ball mills, flotation, coarse ore flotation, gravity concentrator and a molybdenum plant to produce copper and gold concentrate, gold doré and molybdenum concentrate.

Mined ore recovered from the extraction level at the bottom of each cave is crushed in an underground crusher. It is then transported by conveyor to the surface for processing at one of Cadia’s two concentrators, which produce both gold doré (via gravity recovery) and copper concentrate. The gold doré is delivered to a gold refinery in Australia to produce refined gold and silver, while the copper concentrate is slurried and pumped along a dedicated pipeline to the Blayney dewatering facility for filtering before being transported by rail to Port Kembla for export to international smelters particularly in Japan and South Korea. The copper concentrates have final mineral grades of 23-26% copper and 28-66 g/t gold as well as trace levels of deleterious materials such as fluorine and molybdenum. A new molybdenum processing plant was commissioned in 2022 to recover molybdenum into a separate molybdenum concentrate, providing an additional revenue stream and reducing the penalties that would otherwise result from excessive molybdenum content in the copper concentrate.

Concentrator 1 has undergone several upgrades since commissioning in 1998 and currently processes around 26 Mtpa ore using a conventional SABC circuit (SAG mill and ball mill with single stage pebble crusher). The inclusion of high-pressure grinding rolls and third train of flotation cells enables the circuit to treat ore from the Cadia East mine. Increasing throughput has required a coarser primary grind size (over with 80% < 150 microns) and in order to treat the increased tonnage, as well as upgrading and including additional equipment into two of the three flotation trains.

Concentrator 2 was commissioned in 2002, and had a target rate of 4 Mt/a. Concentrator 2 with several upgrades has almost doubled its original capacity and now processes 9 Mtpa. In mid-2008, the facilities were upgraded to suit predictions of harder and fines-deficient ore from Ridgeway Deeps block cave mine. The upgrade included installation of a secondary crushing circuit and additional regrind mill power. A 2.24 MW Vertimill was installed in 2011 to reduce flotation feed size and improve metal recoveries.

Concentrator 1 has historically been referred to as the low-grade process facility, or the Cadia concentrator. Concentrator 2 has historically been referred to as the high-grade process facility, or the Ridgeway concentrator.

Concentrator 1 Design
The key unit operations in the processing plant are:

- Flash flotation cells and gravity concentrators for processing a component of the hydrocyclone underflow streams.
- Three flotation trains comprised of conventional Outokumpu flotation cells

Water Supply

Summary:

er requirements. The water supply system has been designed to recycle as much of the on-site water as possible, with make-up water from local sources as required.

Most water on-site is recycled from the TSF and return water from Blayney Dewatering Facility. Make-up water is extracted from the Belubula River, Cadiangullong Dam, Flyers Creek Weir, Cadia Creek Weir, Orange, and Blayney Sewage Treatment Plant treated effluent, on-site groundwater extraction bores, and site runoff.

Agreements are in place with the City of Orange and the annualised license agreement with Newcrest is reviewed annually. The Newcrest LOMP assumes that between 65% to 70% of water used is recycled, however Cadia continue to work on further water saving initiatives. To address the additional water required for an expansion to 35Mtpa, in the context of a history of periodic drought, Cadia has included a new South Water Storage Dam in the EIS. In addition, Cadia is pursuing various other projects to secure future water supplies.

The water management system at Cadia includes separate management systems for clean, mixed and site captured water. The surface water management system at Cadia involves a number of interlinked dams and their catchments, tailings storage facilities, Cadia Hill open pit, the underground mining operations and the water pumping systems. The majority of the site water requirement is for minerals processing, with minor amounts used in mining, dust suppression and for ancillary

Commodity Production

Operational metrics

Personnel

Job Title	Name	Profile	Ref. Date
Development Manager	Nicholas Fryer		Apr 16, 2024
Development Superintendent	Owen Wells		Apr 16, 2024
General Manager Operations	Tom Lukeman		Apr 16, 2024
Health, Safety & Environment Manager	Greg Taylor-Adams		Apr 16, 2024
Technology Manager	Jason Nitz		Apr 16, 2024