NWT RESEARCH DATABASE

Tags: contaminants, arsenic, sediment quality

Objective(s): To determine whether the arsenic present in regional lake sediments is of natural or anthropogenic origin, and whether these lakes act as a sink (capture) or a source (release) of arsenic in the overlying lake waters.

Project Description: The purpose of this study is to determine whether the arsenic present in regional lake sediments is of natural or anthropogenic origin, and whether these lakes act as a sink (capture) or a source (release) of arsenic in the overlying lake waters. By evaluating the relative stability of arsenic species in these different chemical media, the research team may establish the long term trends of arsenic in the aquatic environment, and its associated risks to ecosystems and human health. A field program will be completed during which three lakes will be sampled: BC-20, Handle Lake and Lower Martin Lake, to the west of Giant mine property. These lakes offer a range of physical and chemical characteristics such as depth of lake, organic contents and nature of substrate. Studying these lakes will allow the research team to better constrain various physical and chemical parameters of lakes geochemistry in relation to arsenic mobility, and associated environmental risks. This will be done by assessing the speciation of arsenic in both lake sediments and associated porewaters using dialysis arrays (peepers), major and trace elements analysis, synchrotron-based analysis, and advanced scanning electron microscopy. This will create an Increased awareness of human health and potential hazards related to arsenic pollution in the lakes surrounding Giant Mine. Presentations will be performed on ongoing research and results at the Yellowknife Geoscience Forum. The fieldwork for this study will be conducted from January 30, 2015 to December 31, 2015.