The seams at Yarrabee in stratigraphic order are: Cancer, Aries, Castor Upper, Castor Lower, Pollux, Orion and Pisces Lower) have been modelled and resourced where supported by adequate data. The lower Orion and Pisces seams are generally thin and of poor quality and thus are not resourced, with the exception of the Yarrabee East South (YES) and Domain 2 South pit areas. In these zones the seams thicken and improve in quality sufficiently to be resourced.

The Yarrabee deposit is located within a fault slice of the Rangal Coal Measures of the Blackwater Group, between the Yarrabee fault on the east and another fault on the west, both faults being thrusts and upthrown to the east.

The overarching structure of the Yarrabee area is an asymmetric south easterly plunging syncline, the Yarrabee Syncline, with the greatest amount of compressional deformation located on the western limb and the northern nodal part of the syncline. The Yarrabee Mine is located between two significant fault structures (most likely faulted zones, rather than single faults) on the east and to the west. Faults strike in a NNE-SSE direction and are upthrown to the east.

The Yarrabee Syncline is itself folded and faulted by smaller fold structures and faults. The anticline structures are typically faulted in the more compressed parts of the Yarrabee area and coal is only present in the synclines. Six thrust faults have been interpreted with the lowest angle faults being loc ........

Yarrabee uses conventional truck and excavator methods. ROM coal is mined from a number of pits and is either processed at the site’s coal handling preparation plant or bypassed for crushing only. About 40% of the ROM coal is bypassed due to its superior in situ quality. Product coal is road hauled to the Boonal load out facility on the Blackwater railway system and then railed 280 kilometres to the RG Tanna and Wiggins Island Coal Terminals at the Port of Gladstone for export to steelmakers in the Asian region.

Yarrabee operations are contained within 10 Mining Leases (ML’s), one Mineral Development Licence (MDL) and four Exploration Permits for Coal (EPC’s). The area covered by these licenses and permits is about 9,100ha with the area having approximate dimensions of 13.5 km north south and 10 km east west.

Mine Design
Seismic hazard studies were not included in the documents available however, the region is classified as a low seismicity area and seismic hazard is not a critical design consideration.

Geotechnical hazards are controlled through mine planning via determination of wall angles, placement of benches and pit wall orientation. Independent geotechnical assessments are conducted annually and recommendations are implemented in the mine plans.

Pits are generally designed to be mined down dip of the deposit to reduce geotechnical hazards. Pit orientation is designed to intersect major faults and the bedding planes in th ........

Since 2009 Yarrabee has been producing low volatile PCI and thermal coal products via open cut mining methods. Coal is either washed in the Yarrabee CHPP to produce PCI coal, or crushed and sold as bypass thermal coal. CHPP reject is separated into coarse and fine streams, with the coarse reject being disposed of in the open pit voids and the fine reject being stored in tailings dam facilities. Product coal is hauled 37km by road truck to the Boonal Loadout Facility which is located adjacent to the Capricorn Highway 10km east of Blackwater and then railed up to 280km to either the Wiggins Island Coal Terminal or the RG Tanna Coal Terminal at the Port of Gladstone.

The CHPP uses standard technology and liberates coal through sizing, gravity and flotation separation. After sizing, dense medium cyclones are used for processing the coarse material and spirals and flotation cell are used for the fine coal.

The CHPP was originally commissioned with a nameplate capacity ........