Summary

Deposit type

• Sedimentary

Summary:

y basin comprising Permian to Triassic age geology. In the vicinity of the project site, the Bowen Basin geology has been folded, forming a broad syncline that plunges and opens to the north. The project site is located on the western limb of the syncline.

Subsequent magmatism has resulted in the formation of localised intrusions of igneous rock within the Bowen Basin sediments. The Bowen Basin sediments are typically overlain by more recent Triassic and Cainozoic age deposits. These deposits (and the upper profile of the Bowen Basin sediments) have been extensively modified by long periods of weathering.

The stratigraphy of the project site and its surrounds includes the following (in descending order):
• Localised alluvium associated with North Creek (not present within the project site);
• Cainozoic sediments, including the Suttor Formation, associated colluvium, weathered sediments, and residual soils;
• Triassic sediments of the Rewan Group;
• Permian coal measures,

Mining Methods

• Longwall
• Bord-and-pillar
• Continuous

Summary:

ommenced bord and pillar mining in 2006 and longwall mining in 2009 and produces export coking and Pulverised Coal Injection (PCI) coal. The CDCM EA prescribes a maximum coal extraction rate of 5 Million tonnes per annum of Run-Of-Mine (ROM) coal.

Mining to date has only been within the Leichardt coal seam. The entire ML area is fully permitted to mine the Vermont seam throughout, which underlies the Leichardt seam 40-60m. Mining of the Vermont coal seam would extend the mine life by another 15-20 years after the Leichardt seam has been mined out.

Underground longwall mininng method to be used until the end of 2023, whereafter the longwall relocates to Ironbark. Mining of Vermont seam will be by Bord and Pillar & Longwall Mining Methods. Bord and Pillar (3 units) for 8-10 years. Longwall recommences in the 2030’s for a further 5-8 years.

Mining at Carborough Downs Mine is currently within the Leichardt seam where the virgin gas content needs to be pre-drained before mining to ensure safe operating conditions. As a result, Carborough Downs utilises a combination of surface to in-seam drilling (SIS) and underground in-seam drilling (UIS) to drain the gas to acceptable limits prior to mining. Surface to in-seam drilling is the primary means of gas drainage at Carborough Downs mine.

A pipeline gathering network has been installed to connect SIS gas wells and to deliver this coal seam gas to an onsite compressor station. The compressed coal seam gas is then transferred via a pipeline to the Moranbah Gas Processing Facility for domestic gas distribution.

The mine produces metallurgical coal sold to meet the growing needs of international steel demand.

The bord and pillar mining method involves dividing the target coal seam with underground roadway excavations. The coal seam is initially excavated along mined roadways (called ‘main headings’). The main headings are intersected at regular intervals by connecting roadways (called ‘cut-throughs’). Collectively, the main headings and cut-throughs are the bords. The cut-throughs are typically mined perpendicular to the primary headings creating a block-like array (or panel) of coal pillars bounded by the bords. Bell outs (small, fan shaped coal excavations) are also created at the ends of the bords to maximise coal extraction.

Mining is carried out by a continuous miner (cutting machine) that loads coal onto a shuttle car which transports and loads the coal onto an underground conveyor belt system. Once a bord is excavated to the required distance, the continuous miner moves to the next mining area and roof support is installed in the previous bord. The coal pillars support the overlying strata as the bords are mined and remain in place after the completion of mining.

PROJECT MINE LAYOUT
The width of the roadways (bords) will be 6 m. The final coal pillars will be 24 m by 24 m of solid coal. The coal extraction height will vary between 4.6 m and 6.0 m.

The project bord and pillar

Comminution

Crushers and Mills

Processing

• CHPP
• Jameson Cell Flotation
• Spiral concentrator / separator
• Wash plant
• Flotation
• Dense media separation

Summary:

seven days a week and is capable of processing 1,000 tonnes per hour.

The mine produces predominantly coking coal with PCI coal as a secondary product.

Coal from the underground workings is transported via overland conveyor to a ROM coal stockpile north-west of the conveyor drift portal. ROM coal is then transported from the ROM stockpile by an overland conveyor to the CHPP. ROM coal is washed at the CHPP. Product coal is transported from the CHPP via an onsite rail loop and train loading facility. Product coal is railed to the Dalrymple Bay Coal Terminal, for export.

CHPP Hub comprises 2x nominal 500tph CHPP Modules (stand alone), greater than 1Mt ROM coal stockpile and 750Kt product stockpile site, able to blend from multiple coal value locations.

Multiple product CHPP modules separated by size and density to multiple coal product specs.

Primary and secondary Dense Media Cyclones with spirals and TBS circuits and Jamieson cell allow ultrafine coal recovery.

Rejects drying circuits with rejects disposal to Dry Rejects Emplacement Area (DREA).

Two export products will be produced from the Project, a low ash coking fraction (HCC) and a pulverised coal injection fraction (PCI). An overall yield of approximately 77% is predicted, of which approximately 63% is expected to be HCC and 14% PCI. After processing, the product coal will be stockpiled at the existing CDCM product coal handling facility and loaded onto trains using the existing rail load-out.

Water Supply

Summary:

rever possible.

Commodity Production

Operational metrics

Personnel

Job Title	Name	Profile	Ref. Date
Executive General Manager	Andrew Vella		Dec 29, 2023
General Manager/SSE	Russell Uhr		Dec 19, 2023