The Range of Environmental Concerns - Mining and the Environment: From Ore to Metal - page 526

FIGURE 13.5
Waste Rock Management in Surface
Mining

OPEN PIT MINING OF HYPOTHETICAL DIPPING DEPOSIT

Out Pit
Waste Rock
Placement

From the environmental viewpoint the
advantages of open cast mining are:
1. The limited need to remove adja-
cent waste rock.
2. The opportunity to deposit waste
rock in mined-out areas.
3. Reclamation and topsoil use can
follow mining immediately.
Photo: Kennecott Bingham Copper
Mine, www.bettermines.org

Active Pit First Pit

ORE

OPEN CAST MINING OF HYPOTHETICAL HORIZONTAL DEPOSIT

In Pit Waste Rock Placement

First Pit Active Pit

ORE

CASE 13.4
Use of Red Mud for Manufacture of Bricks

The aluminium industry has over a long period, con-
ducted extensive research into alternative benefi cial
uses for its main waste product - red mud, which is
the tailings remaining after extraction of alumina from
bauxite, using the Bayer process. One alumina producer
sponsored studies into the manufacture of bricks using
red mud as the major ingredient. The results proved

promising with trial batches of bricks having adequate
physical properties and acceptable appearance. Plans had
progressed to discussions with a potential manufacturer
when someone thought to measure the level of radia-
tion from the bricks. While not extreme, the level of
radiation was suffi cient that neither the mining company
nor the manufacturer was prepared to proceed.