Galloway, J.M., Sanei H, Patterson R.T., Mosstajiri, Hadlari T., Falck, H., 2012. Total arsenic concentrations of lake sediments near the City of Yellowknife, Northwest Territories. Geological Survey of Canada Open File 7037, 47 p.
We report on recent geoscience data collected by the Geological Survey of Canada in collaboration with Northwest Territories Geoscience Office and Carleton University. Fifty sediment-water interface samples from 19 lakes were collected between July and August 2009 along a 90 km east-west transect and analyzed for grain size, organic matter, nutrients, and metals. The work was undertaken to establish a dataset to contribute to the determination of natural variability of arsenic in freshwater sediments in the Yellowknife area, Northwest Territories. Geochemistry results of lake sediments are compared to previous work, bedrock geochemistry where available, and the Canadian Council of Ministers of the Environment Interim Sediment Quality Guidelines and Probable Effects Levels for the Protection of Aquatic Life. Concentrations of arsenic in bulk lake sediment samples are elevated above Interim Sediment Quality Quidelines and Probable Effects Levels in lakes located west of the City of Yellowknife. These lakes occur on granitoid bedrock, which contain low arsenic relative to other bedrock types in the study region. The spatial pattern of arsenic in lake sediments is consistent with aerial dispersion of emitted particulates from mine smelting point sources and transportation by prevailing winds west of the City of Yellowknife.