The Mt Owen mine is part of the Mt Owen complex, which lies within the Hunter coalfields at Hebden, in the Upper Hunter Valley of New South Wales. The complex also includes the Ravensworth East and Glendell open-pit coal mines. These operations have been integrated in order that all sites could utilise existing infrastructure and coal handling facilities at the Mt Owen mine. All mines in the Mt Owen Complex are owned and managed by Xstrata Mt Owen, a wholly owned subsidiary of Xstrata Coal.
Mining at the Mt Owen mine is currently carried out using large excavators and haul trucks. The mine produces thermal and semi-soft coking coal for supply to the export markets. The thermal coal product is highly volatile with strong combustion characteristics and has been widely used for power generation as well as for general industrial use. Semi-soft coking coal produced by Mt Owen is used by steel mills for pulverized coal injection and as a component in the coke blend. The coal is low in ash and sulphur.
The current processing capacity of the complex’s coal handling and preparation plant is nine million tonnes per annum of run-of-mine coal, however Xstrata has planned to increase this throughput to reach a rate of 15Mtpa. The upgrade will enable processing of up to 10Mtpa from the Mt Owen mine, and about 5Mtpa from Ravensworth East and/or Glendell.
Mt Owen is situated between two regional thrust faults, the Hunter thrust and the Hebden thrust, that limit the lateral extent of the coal seams. Seam dips vary throughout the deposit, with dips being steep in the areas near the Hunter and Hebden thrusts, where parallel thrusts dislocate the seam by up to 40 metres. Up to 22 mineable coal intervals have been recognised at Mt Owen, ranging in thickness from 0.2m to 10m, within a stratigraphic interval of about 350m. The coal seams comprise a total thickness of about 55m.The seams with potential for economic extraction that have been recognised at Mt Owen include Lemington, Pikes Gully, Arties, Upper Liddell, Middle Liddell, Lower Liddell, Barrett, Upper Hebden and Lower Hebden.