Arsenic and mercury in tailings, Oldham gold district, Nova Scotia

摘要: The mercury content of the tailings in Oldham Gold District is high and consistentat4 ppm on average commonly greater than 10 ppm. Mercury distribution controlled by (a) grain size (finer are more Hg-rich), (b) Au grade (tailings associated with higher areas ( c) amount fine-grained organic matter (more rich samples tend to be Hg-rich). Arsenic concentration arsenopyrite distribution. Redistribution into fine or clay fraction less important for Hg. groundwater has anomalous concentrations As, Fe, Mn, but little free contribute enough As Black Brook increase downstream beyond safe limits; however, buffer acid surface drainage entering tailing from upstream. Vegetation composed genotypes common species capable tolerating both Aquatic accumulate metals, which may reflect active metal uptake passive absorption Hg onto their surf aces. have influence plant communities. Depth water tab le thickness layer most physical features affecting seven communities found site.