5. What can be done to prevent mine drainage from damaging the ecosystem?
Acid mine drainage (AMD) causes environmental pollution that affects many countries having historic or current mining
industries. [ Preventing the formation or the migration of AMD from its source is generally considered to be the preferable
option, although this is not feasible in many locations, and in such cases, it is necessary to collect, treat, and discharge mine
water. There are various
options available for remediating AMD, which may be divided into those that use either chemical or
biological mechanisms to neutralise AMD and remove metals from solution. Both abiotic and biological systems include those
that are classed as bactiveQ(i.e., require continuous inputs of resources to sustain the process) or bpassiveQ(i.e., require relatively
little resource input once in operation). This review describes the current abiotic and bioremediative strategies that are currently
used to mitigate AMD and compares the strengths and weaknesses of each. New and emerging technologies are also described.
In addition, the factors that currently influence the selection of a remediation system, and how these criteria may change in the
future, are discussed.
D 2004 Elsevier B.V. All rights reserved.
Acidic sulfur-rich wastewaters are the by-products
of a variety of industrial operations such as galvanic
processing and the scrubbing of flue gases at power
plants (Johnson, 2000). The major producer of such
effluents is, however, the mining industry. Waters
draining active and, in particular, abandoned mines
and mine wastes are often net acidic (sometimes
extremely so). Such waters typically pose an additional risk to the environment by the fact that they
often contain elevated concentrations of metals (iron,
aluminium and manganese, and possibly other heavy
metals) and metalloids (of which arsenic is generally
of greatest concern). In 1989, it was estimated that ca.
19,300 km of streams and rivers, and ca. ]
There are no new answers.