Palmer, M.J., Galloway, J., Jamieson, H.E., Patterson, R.T., Falck, H., and Kokelj, S.V. 2015. The concentration of arsenic in lake waters of the Yellowknife area 15 years after the end of ore processing operations in the region. NWT Open File 2015-XX, NWT Geoscience Office, Yellowknife.
Ninety-eight lakes were sampled over two field seasons to investigate the elemental concentrations of lake waters within a 30 km radius of Yellowknife. Elevated concentrations of As, Sb, and SO4 were identified within 17.5 km of the historic roaster stacks at Giant Mine. Arsenic concentrations were highest in small lakes downwind and proximal to the historic stacks, suggesting a gradient in impact from historic roaster operations at Giant Mine consistent with predominant wind direction. Concentrations of arsenic exceeded federal guidelines for many of the lakes sampled within 12 km of the roaster stacks, and in some lakes were more than 60 times the federal drinking water guideline of 10 µg/L. This study provides an extensive survey of elemental concentrations in local lakes and should be supported by future work to investigate the specific drivers of variation in arsenic concentration in local lakes, interannual variability in water chemistry and the long-term fate of arsenic and other elements of concern in these lakes.
pdf coming soon