Illawarra Coal's assets are located in the southern portion of the Sydney Basin within the Southern Coalfield.

The full sequence of Triassic to Permian sedimentary units are present within the Illawarra Coal's areas, including the Permian Shoalhaven Group, Illawarra Coal Measures and the overlying Triassic Narrabeen Group and Hawkesbury Sandstone.

Wongawilli Coal ranges between 7 to 11 m thick and consists of inter-banded tuffs, carbonaceous shales and coal. The basal 4 m contains coal of economic potential and is currently mined at the Dendrobium Mine. The Wongawilli Coal is subdivided into 13 individual plies and 12 partings units and into three working sections as shown in. The working sections are based on mining experience and are the most relevant division of the seam. The Second Machine Band working section is generally the target of mining at Dendrobium.

The structure over the Illawarra operation area is relatively well defined based on the geological data available. Seam dips over the area are generally low (1° to 3°). There are localised variations in seam structures. Relatively steeply dipping strata occurring at the Dendrobium Mine between Areas 2 and 3 where dips reach 7° - 8° in an area associated with a small scale fault. The localised steeper dip zones are also often associated with underlying igneous intrusions and domes.

Faulting has been identified across the Bulli Seam Operation and Dendrobium Operation. The faults have been identified by 3D seismic, 2D seismic, underground mapping, underground drilling, de-gassing intra-seam holes and, to a lesser extent, interpreted from floor contours generated from drill-hole data. The faults are predominately extension normal faults, although low angle thrust faults have also been identified (such as Maingate 12 at Dendrobium).

At the Dendrobium Operation only four faults are incorporated into the Dendrobium Operation geological model. Of these, only two are located within the current mine plan:

- Elouera Fault - identified in the old Elouera underground workings, affecting the southern boundary of the area, displacement of up to 20 m.

- WW1 Fault - Small displacement fault (less than 5 m) identified in the northwest mains workings, between Areas 2 and 3. There are a number of features that have been interpreted as probably faulting but to a lesser degree of confidence.

As well as the four modelled faults, there are a number of interpreted fault structures for the Dendrobium Operation. Most of the predicted structures are understood to be minor and not expected to affect mining operation due to their limited throw.

At the Dendrobium Operation Tertiary igneous intrusions, in the form of sills and dykes, post-date the sedimentary strata in the area which hosts the coal. Sills and dykes have been identified through a combination of surface mapping, vertical drilling, in seam drilling, aeromagnetic survey and from mining.

Extensive igneous sills have been identified in the Wongawilli Seam and have had significant impacts on the extent of economic coal at the Dendrobium Operation.

Additionally, there is a swarm of dykes known as the Dendrobium Dyke Zone located directly north of Dendrobium Area 2. The Dendrobium Dyke Zone currently defines the northern limit of the Dendrobium Mine design for Areas 2 and 3.

The Dendrobium Mine extracts coal from the Wongawilli Seam (also known as the No 3 Seam) within Consolidated Coal Lease (CCL) 768 using underground longwall mining methods. The Dendrobium Mine includes five approved underground mining domains, named Areas 1, 2, 3A, 3B and 3C. Longwall mining is currently being undertaken in Area 3B, with extraction largely complete in Areas 1, 2 and 3A.

The Dendrobium Mine primarily produces hard coking coal and is approved to produce up to 5.2 million tonnes per annum until 31 December 2030. The Dendrobium Mine Extension Project (the Project) proposes to extend the mine life at the Dendrobium Mine to 31 December 2041.

Illawarra Metallurgical Coal is seeking an Infrastructure Approval for the Dendrobium Mine Extension Project (the Project), which would support the extraction of approximately 31 million tonnes (Mt) of ROM coal from Area 5 (extraction of the Bulli Seam), within CCL 768. The life of the Project includes longwall mining in Area 5 up to approximately 31 December 2034, and ongoing use of existing surface facilities until 2041 (including for handling of Area 3C ROM coal).

Coal is transported from the underground workings to the Kemira Valley Coal Loading Facility via a conveyor network, reaching the surface via the Kemira Valley Tunnel. The coal is then fed through a coal sizer, into a rill tower and deposited onto a 140,000-tonne capacity stockpile. Coal is loaded onto trains via an enclosed rail-loading chute.

The private Kemira Valley Rail Line (KVRL) is used to transport the coal from the KVCLF to the Dendrobium Coal Preparation Plant (DCPP).

Processing of the ROM coal produced at Dendrobium Mine is undertaken at the DCPP. Coal wash is emplaced at the Appin Mine Coal Wash Emplacement Area (CWEA) or directed to beneficial reuse.

The Dendrobium CPP has the capacity to process up to 5.2 Mtpa of sized ROM coal.

The Dendrobium CPP incorporates:
- Heavy medium drum;
- Primary dense medium cyclone (“DMC”);
- Secondary DMC;
- Froth flotation cells;
- Drum filters;
- Horizontal belt ........