Sunday, November 27, 2016

From MIT (Massachusetts Institute of Technology)

...Underground Mining (click here)

Underground mining has the potential for tunnel collapses and land subsidence (Betournay, 2011). It involves large-scale movements of waste rock and vegetation, similar to open pit mining. Additionally, like most traditional forms of mining, underground mining can release toxic compounds into the air and water. As water takes on harmful concentrations of minerals and heavy metals, it becomes a contaminant. This contaminated water can pollute the region surrounding the mine and beyond (Miranda, Blanco-Uribe Q., Hernandez, Ochoa G., & Yerena, 1998). Mercury is commonly used in as an amalgamating agent to facilitate the recovery of some precious ores (Miranda et al., 1998). Mercury tailings then become a major source of concern, and improper disposal can lead to contamination of the atmosphere and neighboring bodies of water. Most underground mining operations increase sedimentation in nearby rivers through their use of hydraulic pumps and suction dredges; blasting with hydraulic pumps removes ecologically valuable topsoil containing seed banks, making it difficult for vegetation to recover (Miranda et al., 1998). Deforestation due to mining leads to the disintegration of biomes and contributes to the effects of erosion....