NWT RESEARCH DATABASE

Regions: North Slave Region

Tags: physical sciences, mining, water quality, environmental monitoring, air quality, hydrology, sediment quality, soil chemistry, rock chemistry

Objective(s): To continue to describe the existing environment, and obtain information once project activities commence to determine potential project effects.

Project Description: The objective of the proposed studies is to continue to describe the existing environment, and obtain information once Project activities commence to determine potential project effects. The proposed studies will include the collection of air quality, hydrology, geochemistry, vegetation, soil, water and sediment quality, and fish and aquatic resources data and wildlife occurrence. These study programs are designed to extend the baseline knowledge of the Kennady Lake and adjacent watershed areas, which will potentially be affected by future mine development activities. A series of lakes in the Kirk Lake watershed will be used as reference lakes to provide reference data to support future long-term monitoring programs for the Project. Prior to construction, the main basin of Kennady Lake and a small unnamed lake (referred to as Lake D1) may be fished-out during the spring/summer. The work for the hydrology component will include snow course and ice thickness, hydrometric, bathymetric, and channel and shoreline surveys. These surveys will be used to: • characterize the hydrological regime of the watershed; • quantify annual and seasonal water yields and lake water level regimes; • monitor water elevations upstream of the lake outlets during the open water season; • monitor air temperature, rainfall, wind speed/direction and relative humidity using the climate station at the Gahcho Kué Project exploration camp at Kennady Lake; • provide data to support the water quality and fisheries programs of the Aquatic Effects Monitoring Program (AEMP); and • establish a pre-development baseline for key waterbody channels and shorelines using Laser Imaging, Detection and Ranging (LiDAR) topographical data, drone reconnaissance and aerial photographs. The AEMP work for the water and sediment quality component will include: • collection of water quality seasonal data and sediment quality summer data in AEMP core lakes to supplement the baseline data set, and to document the water and sediment quality effects of mine construction (if started); • collection of water quality seasonal data and sediment quality summer data in selected (at least two) reference lakes to supplement the baseline reference data for AEMP studies; and • collection of water quality seasonal data and sediment quality summer data in small lakes and streams in the Kennady Lake and Downstream Local Study Areas and to document the water and sediment quality effects of mine construction. The AEMP plankton monitoring will include: • monitoring the abundance, biomass and composition of the phytoplankton and zooplankton communities in selected waterbodies; and, • measuring chlorophyll a, b and c and nutrient data, specifically total phosphorus (TP), total nitrogen (TN) and soluble reactive silica (SRSi) to support the plankton data. The plankton data will be used to: • identify the biological effects of potential changes in water quality, especially in nutrient concentrations; and, • verifying predictions made in the Environmental Impact Statement (EIS) with respect to productivity of surface waters and hydrological changes (plankton is considered to be the most sensitive biological monitoring component and provides early-warning for other biological components). The AEMP benthic invertebrate community monitoring component will include: • monitoring the biological effects of potential changes in water quality and sediment quality; • verifying EIS predictions in waterbodies affected by hydrological changes; and, • verifying EIS predictions related to lake productivity. The fish program will include: • large and small bodied fish surveys in lakes and streams using various sampling methods, such as small-mesh gill netting, angling, baited minnow trapping and shoreline electrofishing; •large bodied fish tissues and small bodied fish whole-body samples may be collected and archived during the fish surveys for possible future chemical analyses • recording fish habitat information, where required, which will include substrate and bank/shoreline characteristics, depth/width measurements, in situ physico-chemical water quality measurements, and • in-stream discharge/flow measurements. The downstream flow and fish habitat program will focus on the streams and will include: • assessing young of year fish distribution and densities; • collecting physical measurements of water level, depth and velocity; • installing fish fences at two locations in early spring; • executing a spring fish fence program for three weeks (tag fish and install data loggers to record movements); and, • conducting visual assessments and physical measurements of depth and velocity at predefined barriers. “Fish-out” includes fish sampling to remove fish from the main basins of Kennady Lake and a small unnamed lake prior to construction of the mine and to meet requirements of Fisheries and Oceans Canada. Tasks associated with the fish-out will include: • sampling large and small bodied fish using multiple methods; • collecting biological information from fish; • measuring field water quality; and, • potentially conducting hydroacoustics surveys in Kennady Lake in conjunction with the fish-out program. The air quality monitoring program will include: • collection and processing of meteorological data from the onsite weather station at the Gahcho Kué Project exploration camp at Kennady Lake and; • collection and processing of data from local sampling stations for particulate matter and nitrogen dioxide (NO2). The dust, vegetation, and soil monitoring program will include: • monitoring dustfall collectors and collecting dust samples from the collectors every 30 days from May to September; • sampling dustfall for physical characteristics and chemical composition including metals; • sampling permanent vegetation plots at 0 metres (m), 50 m, 150 m, 500 m, 1 kilometre (km), 5 km, 10 km, 15 km and 20 km distances beginning at the Project footprint; • measuring vegetation plots for species composition, percent cover of shrubs, forbs, grasses, bryophytes and lichens, percent cover of surface water, litter, live plants and bare ground, and appearance; • monitoring soil characteristics and salinity information along established transects; • performing soil investigations on horizon, texture, structure, drainage class, moisture regime, nutrient regime, stoniness class, presence of carbonates and/or salts, topographic class, slope position, and ecosystem type; and, • sampling soil for laboratory analysis, pH, and electrical conductivity. The wildlife program will include: • installing and checking wolverine hair snag traps; • installing and checking grizzly bear hair snag traps; • back-tracking barren-ground caribou trails; • conducting an aerial survey for caribou distribution; • conducting routine surveys of the winter road for wildlife occurrence; and, • monitoring for nesting birds within the project area. De Beers Canada Inc. has been proactive in providing information to local communities. Surrounding communities have the opportunity to participate as field assistants, where possible, in the implementation of the various environmental monitoring programs. These communities include, Yellowknives Dene First Nation, Tlicho Government, the North Slave Metis Alliance, the Northwest Territories Metis Nation, and the Lutsel K'e Dene First Nations. De Beers has and will continue to host meetings in all affected communities to provide updates. The fieldwork for this study will be conducted from February 3, 2017 to December 31, 2017.