Mercury levels in surface waters of the Carson River-Lahontan reservoir system, Nevada: Influence of historic mining activities

Mining Activities and Associated Environmental Impacts in Arid Climates: A Literature Review

“…It is known that mining and milling activities concentrate these metals into waste materials and potentially causing environmental impacts at a later time (Besser & Leib, 2000;Berger et al, 2000;Blowes et al, 1994). On the other hand historical mining operations used CN -to remove precious metals from floated slurries of water and crushed ore, and Hg to form an amalgam with other precious metals so that they could be removed (Bermejo et al, 2003;Bonzongo et al, 1996;Churchill, 1999). Disposal of mine waste containing these geogenic elements (e.g.…”

“…Research clearly shows that the mobilization of contaminates from processed tailings through surface and ground water flow has been a focus of studies (Macklin et al, 2001;Hughes & Diaz, 2008;Bonzongo et al, 1996). Furthermore, studies of historic mining and the resulting contamination has been the focus in regions that receive generous amounts of precipitation rather than arid or hyperarid areas.…”

“…An excellent example of how transformation because of microbes can affect their surrounding environment is the methylation of elemental Hg to methyl-mercury (CH 3 Hg + ), a more soluble, bioavailable, and highly toxic form. When CH 3 Hg + enters a water system it can produce fish kills and large amounts of toxic Hg uptake by multiple species resulting in an impairment in higher species and the food web, thus affecting the surrounding environment more so than elemental Hg (Conaway et al, 2004;Hughes & Diaz, 2008;Bonzongo et al, 1996;Mastrine et al, 1999). In the 2, No.…”

“…Methyl-mercury has been a focus of investigations to provide the modes of conversion from elemental to CH 3 Hg + , and the ratios of Hg to CH 3 Hg + (Hughes & Diaz, 2008;Bonzongo et al, 1996;Mastrine et al, 1999). Macklin et al (2001) found that methylation occurs in sediments when Hg is < 15.3 mg kg -1 , than decreasing above 15.3 mg kg -1 because of toxicity (Macklin et al, 2001).…”

“…Historical mining operations used CN -to remove precious metals from floated slurries of water and crushed ore, and Hg to form an amalgam with other precious metals so that they could be removed (Bonzongo et al, 1996;Churchill, 1999). Milling processes tend to concentrate naturally occurring elements (e.g.…”