Some Mines of Interest - Mining and the Environment: From Ore to Metal - page 61

BOUGAINVILLE
The indei nite closure of the Bougainville Copper Mine on Bougainville Island, PNG, in
1989 is likely the most dramatic event illustrating the complex forces that inl uence mine
developments in developing countries. The mine started operation in 1972, but violent civil
unrest lead to loss of lives and the losses of hundreds of millions of dollars. The abrupt clo-
sure of this mine represented a watershed for the industry and has led to the inclusion of
social issues among the most important considerations for new projects in developing
countries.
Bre-X
Based on reported results of exploration, the Bre-X gold deposit in the head waters of the
Busang River in Kalimantan was poised to become the biggest deposit of gold ever discov-
ered. By March 1997 the Canadian company Bre-X Minerals Ltd. reported an estimated
200 million-ounce resource (worth about US$ 100 billion assuming a gold price of US$
500 per ounce). The deposit immediately attracted the interest of the then President
Soeharto of Indonesia plus several large mining companies. The mining company
Freeport started its own due-diligence drilling, and on March 26, 1997 Freeport reported
that its due-diligence cores, drilled only a meter and a half from Bre-X's, showed
'insignii cant amounts of gold.' The next day Bre-X stock lost almost all its value. Industry
journalists soon found evidence that the Busang ore samples had been 'salted' with gold dust.
BROKEN HILL
As the era of mining operations at Broken Hill draws to an inevitable close, the name of
BHP based on the initials of the mining district, one of the largest mining houses, will be
a lasting reminder of the riches it has yielded. The initial discovery of the richly mineral-
ized site occurred in 1883 and, before mining began, Broken Hill was one of the world
largest lead-zinc-silver ore bodies. However there is more than mining to Broken Hill:
about 380 mineral species are either coni rmed, or considered to have occurred in the
Broken Hill ore body, making the site one of the top i ve sources of mineral species in
the world.
BUTTE, MONTANA BERKELY PIT
In 1955, Butte's i rst large-scale open-Pit mine, the Berkeley pit, was constructed. Mining
was discontinued in 1982 after the extraction of 1.5 billion tons of copper ore. As soon as the
mine dewatering pumps were shut down acidic groundwater with pH less than 3 started to
i ll the pit in what now has become the Berkeley pit Lake. The water is also toxic because
large quantities of heavy metals have leached into the pit lake. For now, the Berkeley pit
remains the Environmental Protection Agency's largest Superfund site in the US. That
means that the US Government has deemed the Berkeley pit the number one environmental
hazard facing the USA today. Many promising new technologies are being trialled at this site.