Greenhouse gas emissions

Our work involves using energy to move large volumes of earth and coal. Our energy use forms a large proportion of our greenhouse gas emissions. By moving material in the most efficient way possible, we directly reduce our energy use, greenhouse gas emissions and costs. Energy used on site includes diesel and other fuels, and electricity purchased from external providers.

We track our energy use for every tonne of material we move, set voluntary internal targets for the amount of greenhouse gas emissions produced per tonne of material moved, and report our performance using the measure amount of greenhouse gas emissions per tonne of material moved.

This measure helps drive efficiencies and behavioural change in our business to reduce greenhouse gas emissions from energy used during the mining process.

In addition to the emissions produced from the energy we use, our total greenhouse gas emissions include fugitive emissions. Fugitive emissions of carbon dioxide and methane are naturally occurring in coal seams and are released to the atmosphere during the mining process. Fugitive emissions from open cut mining are not yet able to be accurately measured and we have no control over their release. Fugitive emissions are estimated to be a large proportion of our total greenhouse gas emission footprint.

2010 performance

During 2010 we moved about 960 million tonnes of material compared with 740 million tonnes moved in 2009.

Our business increased greenhouse gas emissions per tonne of material moved by two per cent, largely resulting from longer distances travelled by haul trucks thereby using more fuel.

Our Queensland open cut operations maintained their greenhouse gas emissions per tonne of material moved relative to 2009.

Our NSW operations increased their greenhouse gas emissions per tonne of material moved by three per cent.

During 2010 our underground Kestrel Mine in Queensland increased its emissions per tonne of material moved by 30 per cent relative to 2009. This was mainly from an overall reduction in the volume of material moved in 2010, following the completion of construction works associated with water management structures and site access roads at Kestrel Mine Extension. We report the performance of our Kestrel Mine separately because greenhouse gas emissions and management varies greatly between open cut and underground operations.

The Coal Seam Methane Pilot Project at Mount Thorley Warkworth concluded in December 2010, delivering an estimate of the methane and carbon dioxide within coal seams that are yet to be mined and greatly increasing our knowledge of methane production from shallow coal seams. This project is believed to be a world-first in producing methane from shallow coal seams in advance of an open-cut mine. The drilling programme is being extended to all sites in NSW.