Coal and Other Mining Operations: Role of Sustainability

Mines for which the owner cannot be found, or for which the owner is financially unable or unwilling to carry out cleanup. They may pose environmental, health, safety, and economic problems to communities, the mining industry, and governments in many countries.

Many metal ore bodies and coal deposits contain significant quantities of sulfide minerals – often including the ore minerals themselves. When such minerals are brought to the surface, they react chemically with air and water producing sulfuric acid, which may dissolve other minerals containing potentially toxic elements. This acid drainage from coal and metal mining around the world can pollute water and the surrounding land, affecting plant and animal life. Acid drainage is known as acid mine drainage when it is closely associated with mining activities, and acid rock drainage when this phenomenon occurs naturally, without human intervention. Both phrases are in common use, although particular stakeholder groups have particular preferences related to the controversial nature of this issue.

An organism that thrives in a relatively acidic environment.

The biochemical process whereby ammoniacal nitrogen is released from nitrogen-containing organic compounds.

Irregular, having no discernible order or shape. Rocks or minerals that possess no definite crystal structure or form, such as amorphous carbon.

Extraction of metal from solid minerals into a solution is facilitated by the metabolism of certain microorganisms.

Extraction of specific metals from their ores through biological means, usually bacteria. It is an actual economical alternative for treating specific mineral ores, involving percolation and agitation techniques.

The people living around the mine who are directly affected (both positively and negatively) by the mine’s activities.

Land/water containing concentrations of potentially toxic materials (organic or inorganic) elevated above the natural background concentrations in a particular area. In relation to mining, land or water contamination may occur through fuel spills, runoff from waste rock dumps, leaks from tailings impoundments, windblown dust from tailings and waste rock, smelter emissions, and drainage from mine workings. Contaminated groundwater is caused by the seepage of contaminated waters into aquifers.

A substance in which the constituent atoms, molecules, or ions are packed in a regularly ordered, repeating three-dimensional pattern.

A microbially facilitated process of nitrate reduction that may ultimately produce molecular nitrogen through a series of intermediate gaseous nitrogen oxide products.

Sulfate-reducing bacteria reduce sulfate in large amounts to obtain energy and expel the resulting sulfides as waste; this is known as dissimilatory sulfate reduction. They are anaerobes, which use sulfate as the terminal electron acceptor.

The recovery of metal by electrolysis. An electric current is passed through a solution containing dissolved metals, and this causes the metals to deposit on a cathode.

An immiscible liquid used to extract a substance from another liquid.

A sedimentary rock consisting of hydrated calcium sulfate.

To dissolve minerals or metals out of an ore heap using chemicals. For example, a cyanide solution percolates through crushed ore heaped on an impervious pad or base pads during heap leaching of gold.

An aquatic plant that grows in or near water and is either emergent, submergent, or floating. They provide cover for fish and substrate for aquatic invertebrates, produce oxygen, and act as food for some fish and wildlife.

An organism that grows best in moderate temperature (typically between 15 °C and 40 °C). The term is mainly applied to microorganisms. It is also used to describe mesophilic anaerobic digestion, which takes place optimally around 37–41 °C or at ambient temperatures between 20 °C and 45 °C, where mesophiles are the primary microorganisms present.

Production of methane by biological processes that are carried out by methanogens. A methanogen is a single-celled microorganism and is a member of the Archaea. Archaea are unique because unlike most life on Earth that rely on oxygen and complex organic compounds for energy, Archaea rely on simple organic compounds (e.g., acetate) and hydrogen for energy.

The processes of exploration, mining development, extraction, processing, refining, smelting, and mine closure.

Mineral-bearing rock that can be mined and treated profitably under the existing economic conditions, or those conditions which are deemed to be reasonable.

Process of converting derelict land (land that requires intervention before beneficial use) to usable land and may include engineering as well as ecological solutions.

Environmental cleanup of land and water contaminated by organic, inorganic, or biological substances.

Seeks to artificially accelerate the processes of natural succession by putting back the original ecosystem’s function and form.

Mineral wastes produced from the processing operations after the valuable minerals have been extracted.

The mineral wastes produced during mine development – including overburden and barren rock – and those parts of an ore deposit below the economic cutoff grade. Often, and particularly in some metal deposits, the waste rock may contain sufficient sulfide mineral concentrations to generate long-term acid drainage problems.