Mercury concentrations in surface waters from fluvial systems draining historical precious metals mining areas ink southeastern U.S.A.

摘要: Abstract This study evaluates several southern Appalachian Piedmont mining districts for Hg contamination in surface waters and determines potential relationships between discharged from historical operations site-specific physical factors. Water samples were collected 3 fluvial systems that drain areas where was used to amalgamate Au ore during the 19th century. Each of exhibit similar characteristics such as climate, vegetation, rock type. Total (Hg T ) determinations made using cold vapour atomic fluorescence spectroscopy techniques. Concentrations range 1–3 ng l −1 Arbacoochee, Alabama, South Mountains, North Carolina, Mining Districts 13 Dahlonega District Georgia. The correlation total suspended solids (TSS) at sites good with a coefficient determination ( r 2 0.82. A clear trend environmentally-available Fe (Fe E =0.86) also evident. most likely reflects similarities mechanisms control aqueous concentrations both metals (i.e., particle-reactive nature two elements), allowing sorption onto Fe-oxyhydroxides. Hence, increased loads TSS erosional events are probably responsible higher stream water concentrations. Vegetation these sites, which is heavy due warm, humid climate SE, may help reduce amount released contaminated rivers by controlling erosion, hence, decreasing input particles into streams rivers. These amalgamation techniques those other precious districts, highly Comstock Au–Ag district Nevada, yet orders magnitude lower; difference concentration correlate relative amounts each. However, variables evaluated determine if physio-chemical differences could influence areas.