Cloudbreak

The Cloudbreak open cut iron ore mine in Western Australia's rich mineralised Pilbara, has been mining and processing over 40 million tonnes of iron ore a year ever since it first began production in 2008.

Iron Ore Deposits at Cloudbreak Exist in Vertical Formations

Where the conventional method of removing overburden at the Cloudbreak open pit mine by means of blasting the rock, shovelling it into trucks and placing it in areas that have been mined out, is carried out in the usual manner, the operator had to devise a more radical way of extracting the ore itself. This was because the ore exists in vertical deposits. Once extracted, ore is handled in the following manner:

ï Once the iron ore is extracted it has to undergo screening de- sanding and crushing at the Cloudbreak ore processing plant. This processing plant prepares and refines the iron ore before it is stockpiled to await transporting.

ï The loadout facility used to load the train wagons is able to load the 2.7 kilometre long trains at a rate of 16,000 tonnes of ore an hour. Each train carries a load of 30,000 tonnes.

ï Once loaded the train takes its load 256 kilometres to the company's ship loading facility at the Herb Elliot Port at Port Hedland.

ï The Fortescue railway line is constructed so it is able to withstand individual wagon axle weights of 40 tonnes, the heaviest in the world. The company rail stock comprises 900 freight wagons and 15 GE diesel locomotives. These make up four trains that make the journey from the Cloudbreak Mine to the coast in five hours. The first train to leave the Cloudbreak open cut iron ore mine to travel to Port Hedland did so on April 5, 2008.

ï The Herb Elliot Port facility at Port Hedland, that covers an area of two million square metres, incorporates both shipping and railway infrastructure and is owned and operated by 'The Pilbara Infrastructure,' a fully owned subsidiary of Fortescue Metals.

Open Cut Strip Mining Method Used at the Cloudbreak Open Cut Mine

The ore deposits at the Cloudbreak open pit mine are extracted by means of open cut strip mining. The various pits are progressively mined with the removed overburden used as backfill for the older pits. However, it is found necessary for groundwater levels to be lowered to below the pit floor. This is obtained by re-injecting water, by means of injection bores and multiple pipes, into several acquifers. The ore itself is removed with the use of surface miners, excavators and face shovels. The larger and more advanced 4200 surface miners were installed at the Cloudbreak Mine in 2011. When the occasion arises whereby narrow bands of ore have to be removed, that the surface miner can't access, excavators are used.

Big Expansion Planned

Fortescue is currently planning an expansion of its Cloudbreak Mine from its present 30 hectares to 45 hectares. This will allow it to increase production to 50 million tonnes a year over a 14 year period. Part of the expansion will include an upgrading of the ore processing plant to allow it to accommodate an ore wash facility that will wash the saline ore that is occasioned during the latter stage of mining out a strip. The depth of the pit will also be increased to 90 metres below the surface.