Characterizing Arsenic Deposition and Mobility in Terrestrial and Aquatic Ecosystems of the ‘Lake 10’ Catchment, NWT
Wednesday, November 21, 2018 - 16:30 to 19:00 Multiplex Gym (DND)Abandoned mine sites in Canada’s Northwest Territories prompt uncertainty regarding the extent of legacy metal pollution. Additionally, warming of subarctic regions is leading to changes in hydrology and dissolved organic matter (DOM), which can affect the fate, mobility, and toxicity of legacy mining pollutants. Here we focus on possible far-field arsenic pollution from Giant Mine. Laboratory analyses on a sediment core from ‘Lake 10’, located 57 km northwest of Yellowknife, has identified evidence of arsenic enrichment in the latter part of the 20th century consistent with the emission history of Giant Mine. These results provide the foundation to assess potential mechanisms that may mobilize arsenic from the landscape to the aquatic ecosystem. To characterize linkages of metal mobility between terrestrial and aquatic ecosystems, we will: (1) identify stores of metals in multiple terrain units and the aquatic ecosystems, (2) investigate the hydrological and biogeochemical pathways for metal mobility, and (3) probe for how climate change may alter these stores and processes.