Mine reclamation

Mine reclamation is the process of creating useful landscapes that meet a variety of goals, typically creating productive ecosystems (or sometimes industrial or municipal land) from mined land. It includes all aspects of this work, including material placement, stabilizing, capping, regrading, placing cover soils, revegetation, and maintenance.

Modern mine rehabilitation aims to minimize and mitigate the environmental effects of modern mining, which may in the case of open pit mining involve movement of significant volumes of rock. Rehabilitation management is an ongoing process, often resulting in open pit mines being backfilled.

After mining finishes, the mine area must undergo rehabilitation.

• Waste dumps are contoured to flatten them out, to further stabilize them against erosion.
• If the ore contains sulfides it is usually covered with a layer of clay to prevent access of rain and oxygen from the air, which can oxidize the sulfides to produce sulfuric acid.
• Landfills are covered with topsoil, and vegetation is planted to help consolidate the material.
• Dumps are usually fenced off to prevent livestock denuding them of vegetation.
• The open pit is then surrounded with a fence, to prevent access, and it generally eventually fills up with groundwater.
• Tailings dams are left to evaporate, then covered with waste rock, clay if need be, and soil, which is planted to stabilize it.

For underground mines, rehabilitation is not always a significant problem or cost. This is because of the higher grade of the ore and lower volumes of waste rock and tailings. In some situations, stopes are backfilled with concrete slurry using waste, so that minimal waste is left at surface.

The removal of plant and infrastructure is not always part of a rehabilitation program, as many old mine plants have cultural heritage and cultural value. Often in gold mines, rehabilitation is performed by scavenger operations which treat the soil within the plant area for spilled gold using modified placer mining gravity collection plants.

In the United States, mine reclamation is a regular part of modern mining practice.^[1]

See also

• Surface Mining Control and Reclamation Act of 1977
• Land rehabilitation
• Mine closure planning

References

1. ^ Surface Mining Control and Reclamation Act of 1977

External links

• Mineral Information Institute (reclamation stories)
• Abandoned Mine Land Reclamation (US Dept. of the Interior)
• Abandoned Mines | Photos & History