Mount Thorley Warkworth

Mining and Processing

MTW is an open-cut, multi-seam, strip-mining operation. The mining process begins with the removal of vegetation and topsoil which is later place on rehabilitated areas. Drill and blast techniques are utilised to fragment the waste rock and coal. Coal is extracted via multi-bench strip mining methods. Electric shovels and trucks are employed in the pre-stripping process to remove upper waste benches. Further waste is then side cast using three draglines to mine to a depth of more than 175 metres below surface. Coal is mined from the pit using hydraulic excavators and front-end loaders and transported to the Run of Mine (ROM) pads or directly to the Coal Handling and Preparation Plant (CHPP) via rear dump trucks.

MTW has two separate coal preparation plants.  Once ROM coal has been prepared by crushing, it is "washed" which separates the clean product coal from and the waste material. The cleaned coal, which is ready for sale is transported by conveyor belt to product stockpiles according to quality. The coal is then loaded onto trains and railed 85 kilometres to Newcastle for export, or delivered by conveyor belt to the local power station.

Both the mine and preparation plants operate on 24 hour per day, seven days per week. MTW's total workforce consists of 650 full time employees and up to 350 contractors depending on major projects and maintenance programs. 

Production and reserves

MTW's Marketable Reserves as at December 2006 were 274 million tonnes. These reserves provide a long mine life with open cut operations expected to continue until 2036. With the prospect of other coal resources and more investigation studies, mining has the potential to continue beyond this time by underground methods.

MTW is planning to produce in excess of 10 million tonnes of product coal in 2008 consisting of high quality semi-soft coking coal, and export and domestic thermal coals.

Coal produced is sold mainly into the export market as well, MTW supplies Redbank Power Station, immediately adjacent to the mine with a fuel called Beneficiated Dewatered Tailings.  This consists of fine coal reclaimed from the reject material in washing coal at the North Preparation Plant, that would have otherwise have been disposed of as tailings waste.