Arsenic mobility from arsenopyrite-rich gold mine waste, Snow Lake,Manitoba, Canada
High concentrations of arsenic occur in one groundwater monitoring well (MW17) at the gold mine site in Snow Lake Manitoba. The likely source of As is an Arsenopyrite Residue Stockpile (ARS) containing arsenopyrite concentrate, which was capped in 2000. Another possible source is the emergency discharge area for Nor Acme tailings, through which MW 17 is drilled. Pore water in the unoxidized zone of the ARS contains up to 100mg/L total arsenic (＜25 mg/L As (Ⅲ)) possibly remobilized from secondary phases, amorphous iron sulfo-arsenates, scorodite and jarosite formed prior to capping by oxidation of primary sulfide minerals.Hydrological modeling suggests that As is transported into the aquifer from the ARS by advection and diffusion.The concentration of As in other monitoring wells within the aquifer in the vicinity of the ARS and the Nor Acme tailings is ＜0.1 mg/L, and in the pore water of the tailings ＜5 mg/L. This indicates that the tailings are unlikely to be the source of the contamination. Attenuation of As in surface waters appears to be adsorption of As(Ⅴ) on Fe-oxyhydroxides such as ferrihydrite, but in the aquifer, the majority of the As is the more soluble As(Ⅲ). Snow Lake, the source of drinking water for the town of Snow Lake has very low concentrations of As.
S.Simpson K.Salzsauler B.L.Sherriff N.Sidenko J.Van Gulck
Department of Geological Sciences, University of Manitoba, Winnipeg, Manitoba, Canada VGQ Consulting Inc., Kitchener, Ontario, Canada;University of Manitoba, Winnipeg, Manitoba, Canada
国际会议
第十二届水-岩相互作用国际研讨会(P0roceedings of the 12th International Symposium on Water-Rock Interaction)
昆明
英文
1261-1265
2007-07-31（万方平台首次上网日期，不代表论文的发表时间）