One of the most interesting anomalies in Australian environmentalism is that the alumina industry is destroying the jarrah forest - and nobody seems to care. At least, nobody is complaining.
Open cut mining of State Forests in Western Australia by two alumina producers (Alcoa and Worseley) has been going on for about 40 years. Mining involves clean cutting of the forest (removal of all saleable timber, including woodchips), full agricultural clearing, blasting with explosives and then removal of the forest soil. This converts the jarrah forest into a patchwork of pits 8-10 metres deep and up to 40 hectares in size. In and around the pits the remnant forest is criss-crossed with haul roads, crusher sites, conveyor belts and power lines. The rate of forest clearance is about 1,000 hectares a year. It is estimated that mining will proceed for at least another 50 years.
The mined-out pits are “rehabilitated” by smoothing the edges, ripping the pit floor (a white kaolinitic clay) with bulldozers and replacing a film of topsoil. Various tree and shrub species are then sown or planted. Pre-1988 the revegetation was basically a plantation of exotic species, mostly eucalypts indigenous to New South Wales; post 1988 the main tree species planted or sown is jarrah.
Jarrah (Eucalyptus marginata) is a tall long-lived tree noted for its superb timber, toughness and resilience. It grows in a relatively harsh environment of long dry summers, frequent fire, and infertile soils. Jarrah occurs only in a restricted area in the southwest of Western Australia. Most of the northern jarrah forest is also an important water resource area and protects the city and goldfields water supply catchments. It also provides important habitat to native species, a range of recreational activities and is famous for its springtime display of endemic wildflowers.
Jarrah timber played an important role in the development of Western Australia. It was used almost exclusively in the construction of the state’s harbours, bridges and railways, for telephone and electricity distribution, for house and building construction, for fine furniture manufacture and domestic and industrial firewood. For many decades it was the state’s third most valuable export (after wheat and wool) and was regarded as one of the world’s most beautiful, as well as strongest and most durable timbers.
In a biogeographical and ecological sense, the jarrah forest is virtually an island. It falls within the Australian southwest botanical province, known as a biodiversity hotspot - most jarrah forest can carry 60 or more different species of plants in the understorey - and is home to a unique fauna.
To the west of the forest belt is the coastal sandplain, these days increasingly becoming one large residential subdivision. To the north and east are the cleared agricultural regions and to the south the narrow strip of karri forest and the Southern Ocean.
The forests were traditionally managed for water production, catchment protection, sustainable timber production, wildlife conservation and recreation. In more recent times the management priority has been designated simply as “conservation of biodiversity”, but as we shall see, this is subservient to minerals production.
The jarrah timber industry scarcely now exists. This has been virtually extinguished over the last five years as logging became a politically unacceptable activity in the state’s forests. The few small timber production operations remaining are all based on regrowth forests, where they are under constant challenge from protest groups whose aim is the total elimination of the industry.
Jarrah forest soils are lateritic and contain bauxite. This is the ore from which alumina and ultimately aluminium is produced. In the 1960s, the state government issued leases for bauxite mining over 800,000 hectares of jarrah forest, and put in place State Agreement Acts which guaranteed easy access to the leaseholders.
Mining commenced in the forest in the mid-1960s and expanded rapidly. At first there was a single mine near Jarrahdale. The ore was railed to a refinery at Kwinana. Before long a new refinery had been built near Pinjarra and new mines were opened up at Del Park and Huntly on the banks of the South Dandalup dam (part of Perth’s water supply). By the early 1980s there was a third refinery at Wagerup, a new mine in State Forest south of the Murray River, another mine at Mt Saddleback and a fourth refinery near Collie.
As recently as 2006 the Western Australia Environmental Protection Authority approved a further expansion of the rate of mining for the Wagerup refinery, and there are current moves by the state government to expand the rate of mining for the Worsely refinery, so that it is likely that the annual rate of forest destruction will soon exceed 1,000 ha.
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