The project area is located within the Hunter Coalfields of the Sydney Basin and includes coal resources and reserves that occur within the Foybrook Formation. This formation is part of the Vane Subgroup of the Whittingham Coal Measures and is the basal coal bearing sequence of the Singleton Supergroup. The areas to be mined are located on the western and north-eastern limbs of the Camberwell Anticline.

The major coal seams identified in the Project Area are, in descending stratigraphic order, the Lemington, Pikes Gully, Arties, Upper Liddell, Middle Liddell, Upper Lower Liddell, Lower Lower Liddell, Upper Barrett and Lower Barrett seams. These seams occur in the lower 180m of the Foybrook Formation. In the eastern part of the project area, the sequence has been progressively eroded until at the eastern boundary only the bottom 100m or so has been preserved.

Ashton intends to mine the ULLD seam by conventional retreating longwall mining methods. Seam thickness varies between 1.7 metres to 2.8 metres within the extraction area. Extraction height will typically be 2.5 metres.

Development roadways are generally driven at 2.7 metres high x 5.4 metres wide by single pass continuous miners. Coal quality, geotechnical, geological and equipment issues will be the main drivers for variation in development or longwall extraction heights.

The CHPP and rail loading facilities is operated 24 hours per day, 7 days per week.

ROM coal facilities includes a 40,000t stockpile for the underground mine and a 25,000t stockpile for the open cut mine. An underground reclaim conveyor will transfer coal from the ROM stockpiles to the CPP via primary and secondary crushers. The CPP is a single module dense medium spiral plant with a capacity in the region of 700t/hr.