Bulga Coal is located in the central coal producing region of the Hunter Coalfield. The many seams of this coalfield were formed in the Permian period and are similar in age to the Illawarra Coal Measures south and west of Sydney, and the Newcastle and Tomago Coal Measures of the Newcastle/Maitland area. The coalfield strata in the Hunter Coalfield generally dip to the west south-west under the prominent sandstone escarpments of the Sydney Basin. A series of folds, superimposed upon the regional dip, form large north-south trending anticlines, synclines and monocline structures. The coal seams within Bulga Coal, which form part of the Wittingham Measures, dip steeply in the east from where they outcrop. The seams have been folded by the Mount Thorley Monocline to level out forming part of the gently dipping strata of the Singleton Super Groups.

Bulga Coal comprises two coal mining operations, being Bulga Open Cut and Bulga Underground Operations.

Bulga Open Cut
Bulga Open Cut continued mining coal reserves from the East Pit, Main Pit, Woodlands Hill Pit and Whybrow Wedge in 2021. In the Woodlands Hill Pit, mining progressed in a westerly direction. In the East Pit, Main Pit and Whybrow Wedge, mining progressed in a southerly direction.

Bulga Open Cut placed overburden on the inside of the Noise and Visual Bund, Eastern Emplacement Area, Southern Extension Dump and undertook in-pit dumping in the Main Pit and East Pit. Overburden was stripped and coal mined using a fleet of excavators and trucks.

ROM coal was transported by dump truck via an overpass on Broke Road to the ROM coal hopper or stockpile at the CHPP.

Bulga Underground Operations
Bulga Underground Operations comprises the sealed Blakefield South Mine, along with the approved, but not commenced, Blakefield North Mine.

Mining of Blakefield South Longwall 1B was completed on 3 May 2018, following which underground mining at Bulga Underground Operations ceased and the Blakefield South mine was sealed. The Blakefield North Mine has been postponed; however, the associated pre-drainage wellfield continues to be operated to supply the gas fired power station. The Blakefield South Pit Top facilities have been demolished to allow the progression of open cut mining.

Bulga Underground Operatio ........

Once mined, the coal is transported to the Coal Handling and Preparation Plant where the minor waste component, usually clay or sandstone, is washed away. The waste is either disposed into tailings dams or thickened and co-disposed in the overburden dumps.

The coal is broken down to particles of less than 125 millimetres in a crusher and then washed, screened, rinsed and dewatered.

The product coal handling facilities include dual product conveying systems from the plant out to the stockpiles.

The CHPP can produce two streams of product coal; semi-soft coking coal and thermal coal.