Huntly

The Alcoa owned Huntly bauxite mine in Western Australia, that was established in 1976, mines bauxite for processing at the Kwinana and Pinjarra refineries. Bauxite ore from the Huntly and Willowdale mine, that is also owned by Alcoa, produce 10 million tonnes of alumina annually. These two mines produce close to 30 percent of Australia's total aluminium production and 45 percent of its total alumina production. They substantially contribute to Alcoa's total Western Australia bauxite refineries output of alumina that accounts for around 11 percent of the world's requirements.

† Rehabilitation is Ongoing at the Huntly Bauxite Open pit Mine
One of the most important aspects of mining bauxite at an open pit the size of the Huntly operation is in having its rehabilitation work keep up with the mining process. This means the Huntly mine is having to rehabilitate around 600 hectares of mined out areas each year. This type of dedication is required to ensure the restoration of the area's jarrah forest ecosystem.

The profile of the soil at the Huntly Mine consists of a number of layers. The top layer, that is about 15 cm in thickness, contains a lot of seed and nutrients that are needed at a later date for adequate forest rehabilitation. The next layer, the overburden layer, varies from about 20 cm to 80 cm of a gravel type sub-soil that is positioned above a solid concrete like caprock. Both these layers have to be removed by scrapers and small excavators before being stored on site before the caprock can be removed by blasting.

Bauxite ore Taken From the Huntly Mine to the Refinery by Conveyor
The bauxite orebody, that is located beneath the broken caprock, is removed by an excavator and loaded into haulage trucks to be taken to the crusher. The crusher at the Huntly processing plant breaks down the bauxite ore to a more suitable size for transportation by conveyor to the refinery.

Rehabilitation Process Developed Over 35 Years
The Huntly bauxite open pit is continually being rehabilitated as mining continues at the site. When an area becomes mined out and the haulage roads are no longer required to take mined ore from the pit in that area, work starts on re-establishing a self sustaining jarrah forest ecosystem. This process has been developed and continuously improved on over the last 35 years. Large rocks are buried, pit faces that are vertical are flattened and the floor of the pit contoured to fit in with the surrounding landscape, after being ripped to break up the rock hard compaction caused by heavy mining equipment. The ripping process helps water and roots penetrate through the soil to facilitate growth.

Mining at the Huntly Mine Expected to Expire in 2044
The mining lease at the Huntly mine covers an area of around 7,000 square kilometres and at current production levels is expected to allow continuous mining of bauxite at the site until 2044. Huntly bauxite is low in both reactive silica and alumina grade This means it doesn't require a lot of caustic soda in its processing which reduces production costs considerably.

The Huntly open cut bauxite mine is often referred to as the Jarrahdale, Willowdale or Ifu Mine. It is located in south west Western Australia 41 kilometres from Perth.