Permafrost is a layer of soil, rock, and organic material that remains frozen for at least two consecutive years.

Open-pit mining involves removing the overlying soil and rock to expose the mineral deposit, which is then extracted.

Mining activities can disturb the permafrost, causing it to thaw and release greenhouse gases, such as methane and carbon dioxide.

Thawing of permafrost can lead to increased flooding, ground subsidence, and the release of toxic chemicals that were previously trapped in the frozen ground.

Thermokarst is the process of melting and refreezing of permafrost, resulting in the formation of various landforms such as sinkholes, lakes, and gullies.

Mining activities can lead to habitat loss for wildlife, disruption of migration routes, and alteration of water flow patterns, all of which can have negative impacts on the local ecosystem.

Placer mining involves the extraction of minerals from placer deposits, typically using methods such as panning, sluicing, or dredging.

Placer mining can lead to sedimentation of waterways, mercury contamination, and deforestation, all of which can have negative impacts on the environment.

Underground mining involves the extraction of minerals from underground deposits, typically through the construction of tunnels and shafts.

Underground mining can lead to acid mine drainage, groundwater contamination, and land subsidence, all of which can have negative impacts on the environment.

Hydraulic mining involves the extraction of minerals from ore deposits using a high-pressure stream of water.

Hydraulic mining can lead to erosion and sedimentation, water contamination, and habitat destruction, all of which can have negative impacts on the environment.

Solvent extraction involves the extraction of minerals from ore deposits using chemical solvents.

Solvent extraction can lead to groundwater contamination, air pollution, and the release of toxic chemicals, all of which can have negative impacts on the environment.

Pyrometallurgy involves the extraction of minerals from ore deposits using high temperatures.

Pyrometallurgy can lead to air pollution, water contamination, and land contamination, all of which can have negative impacts on the environment.