NWT RESEARCH DATABASE

Tags: water quality, aquatic ecosystems, mining impacts, fish, habitat assessment, benthic invertebrates, monitoring, habitat

Objective(s): To determine if the EKATI Diamond Mine is having an effect on its surrounding aquatic environment and to provide baseline data for the area.

Project Description: The aim of the proposed fieldwork is to characterize baseline and post-baseline conditions in the lakes and streams near mining activity. Anticipating future development, baseline data will be collected in Lac du Sauvage. The tenth year of post-baseline data will be collected in the Koala Watershed, the ninth year of monitoring the fish populations of the Panda Diversion Channel (PDC), and the seventh year of post baseline data collected in the King-Cujo Watershed. The PDC is compared with two nearby natural streams to assess its habitat. Monitored parameters for all areas include some or all of the following: hydrology, meteorology, water quality, limnology, sediment quality, phytoplankton, zooplankton, benthos, fish habitat, and fish communities (physical characteristics and sampling of tissue for metals analysis). Research will be based out of EKATI Diamond Mine, 300 km NE of Yellowknife (110º621' E longitude, 64º716' N latitude). Transportation to and from lake sites will be by helicopter. A small outboard motor boat will be used to collect the samples from the lakes. During the week of spring freshet, hydrology and meteorology stations will be set up, and data loggers serviced once a month until the end of the field season. Water quality, phytoplankton and zooplankton samples will be collected using a GO-FLO cylindrical PVC water sampler. Measurements of dissolved oxygen and temperature will be taken with a multimeter. Benthos and sediment quality will be measured using an Ekman grab sampler. Fyke nets, dip nets, minnow traps, fish boxes, electrofishing and 1.5 inch sinking gillnets will be used to sample fish. Gillnets will be set for short periods (i.e., approximately 1 hour) to reduce fish mortality. A maximum of 20 lake trout and 20 round whitefish will be sampled for tissue analysis. Habitat assessment of littoral zones will also be conducted in two lakes using an underwater camera. Results will be publicly available through BHP Billiton in a Final Summary Report. Fieldwork will be conducted from June 1 to December 31, 2007. Over 80 lakes and nearly 60 streams in the region 64° 27’ – 64° 55’N by 109° 59’ – 110° 53’W will be sampled.