Nunavut's economy is on the cusp of unprecedented growth spurred by new gold production and the development of new mines. To sustain this level of growth, it is equally important to safeguard the natural resources in the region by monitoring any human disturbance caused by mining, construction or related activities. BIM's Mary River Project serves as an example of how human impact can be accurately identified in such areas and how stakeholders can work together to mitigate those impacts.
Canada’s largest territory, Nunavut, has extraordinary untapped mineral potential — diamonds, gold, uranium and iron, among others. Nunavut, which means “our land” in the local language, is also known for its inhabitants: the Inuit indigenous people and the barren-ground caribou.
Caribou, a species of deer, is an important subsistence animal for Inuit who have been using it for food, clothing, tools, containers, toys and even shelter. Caribou meat, when it can be found outside of northern Canada, is a delicacy in southern restaurants. Contemporary Inuit artists continue to find new ways to use caribou — creating artwork such as carved antler, beaded caribou hide and caribou hair tufting.
As one of the world’s migratory wildlife species, barren-ground caribou are an important terrestrial subsistence resource in the circumpolar arctic/subarctic region.
On the eastern margin of the Canadian Arctic Archipelago lies Canada’s largest island, Baffin Island, Nunavut. The island’s vast mineral wealth has attracted prospectors and mining companies for decades including Baffinland Iron Mines Corporation (BIM), whose iron mine—the Mary River Project—operates year-round in the northern part of the island. Considered among the richest iron ore deposits in the circumpolar region, the mine produces and ships more than four million tonnes of iron per year to foreign ports and plans to further increase output in the coming years.
“BIM’s operation, from mining through to crushing, trucking and shipping, all takes place on their mine, tote road and port sites. While the Mary River region consists of several high-grade iron ore deposits, BIM has been focusing on Deposit No. 1. Once blasted, they use hydraulic excavators and large front-end loaders to load 90-tonne haul trucks. Ore is delivered to nearby portable crushers. One of their biggest priorities has been to ensure safety as well as minimize any kind of environmental impact from their operations,” says Mike Setterington, lead wildlife consultant for BIM.
While the economic impact of mining projects cannot be disputed, it is important to understand their potential impact on local wildlife and its habitat. The process can be challenging and often involves scrutiny from a variety of stakeholders.
Setterington adds, “caribou are culturally significant to Inuit and provide an important source of food; we had to make sure that operations didn’t pose an unacceptable risk to the local caribou population.” Caribou are an established traditional resource for Inuit subsistence hunters and since more than half of Nunavut’s human population lives on Baffin Island, the presence of a large mine, such as the Mary River Project, poses an important question: Could the mine impact the Northern Baffin Island caribou herd and its habitat?
To find the answer, BIM engaged Environmental Dynamics Inc. (EDI), a company that specializes in the environmental assessment of living things and where they live. Founded in 1994 in Prince George, BC, EDI currently has offices in Whitehorse, Grande Prairie, Calgary, Saskatoon, Nanaimo, Victoria and Burnaby. The environmental consultant has been involved in the Mary River Project since 2007 and has conducted several terrestrial wildlife baseline studies and environmental impact assessments in Baffin Island.
When EDI first began working on the project, one of the first challenges it faced was the lack of data available for north Baffin Island—baseline inventories had to be collected first-hand. The team approached local community elders to gather and incorporate traditional knowledge for research and survey activities.
Leveraging Traditional Knowledge
“We started doing workshops with Inuit and developed a series of maps for the people to draw and write on. We visited the communities and sat down with the elders—people who grew up on the land—to find out how they used the land and the importance of wildlife in a traditional and contemporary sense,” remarked Matt Power, EDI’s GIS manager.
“These workshops focused on caribou migration, calving and other critical habitat areas. We also focused our efforts on hunting areas, travel routes and camps. We wanted to know where the caribou and the people were—we wanted to know how they were connected. This became an important piece of the engagement phase.”
Once some traditional knowledge was gathered, the points, polygons and lines that were drawn on the workshop maps by Inuit elders were digitized in ArcGIS Desktop enabling a full presentation of all the data across Baffin Island and the herd’s range. Based on these results, the team became aware of the added importance of caribou to the people of Baffin Island, so they decided to take the assessment to the next level and develop a Resource Selection Probability Function (RSPF) model.
Proactive community consultation has helped lay the foundation for the success of the Mary River Project.
Using ArcGIS to Determine Caribou’s Habitat
The RSPF includes a class of functions that are used in spatial ecology to assess which habitat characteristics are important to a specific species of animal. In this case, the scale they used to model the function was the resource or probability of habitat selection within the caribou’s home range. This landscape-based model provided the team with the ability to assess caribou’s probability to select certain habitat types; it allowed them to look at where caribou were more likely to be (and not to be) found. The goal was to overlay this baseline habitat information with the mine infrastructure to examine the mine’s potential impacts on caribou and its habitat. EDI selected ArcGIS to drive the model’s development and analysis.
“We leveraged Esri ArcGIS Desktop to carry out all spatial functions and processes. More specifically, the ArcGIS Spatial Analyst extension became instrumental in providing us with the necessary tools for the spatial analyses and modelling. We used Raster Calculator to create and run map algebra expressions that would output raster datasets. Additionally, we were able to incorporate several processes into one complex tool using ModelBuilder—another value-added feature in ArcGIS Desktop,” says Power.
For Power and his GIS team, the top consideration for the habitat analysis was the data (and its integrity). In this case, they had limited data to work with; however, with research and assistance from the public, government and private resources, they were able to compile the required data and create the inputs for the model. The Government of Nunavut provided GPS/satellite data from collared caribou, which enabled the GIS team to compile information relating to a caribou’s location at a given time across the landscape. Collar data was collected in point format and was used to extract values from landscape data showing what environmental characteristics the caribou were selecting.
The results from the point data extraction were saved as data tables that would lay the foundation for the RSPF model. The data were then handed off to statistical experts to determine which environmental conditions caribou showed an affinity to. The statistical process produced the coefficient input, which provided calculation values for the development of the final RSPF model.
Coefficient Input Table
Each raster layer was multiplied by a corresponding coefficient and combined into a single raster which resulted in a quantifiable habitat layer for selection probability.
With the RSPF, the team was able to establish a clear baseline inventory of the availability and suitability of caribou habitat. From the combination of raster inputs and by applying the coefficients, each cell was assigned a value relative to what’s on the land and how suitable it is for the caribou. For instance, a lower value means that the area is likely not suitable for caribou habitat and hence if altered or affected, it is less likely to impact the caribou population. In contrast, higher habitat values, if impacted, would show more effect on caribou. The next step for EDI was to determine the level of impact.
This map shows the final RSPF model to the extent of the North Baffin caribou herd range. Green indicates higher probability for habitat selection by caribou whereas yellow indicates a lower probability.
To assess the mine’s potential impact on caribou habitat selection, the team performed a Zone of Influence (ZOI) analysis on the RSPF. The ZOI applies multipliers to the RSPF in a gradual, decreasing method to show higher levels of impact close to the operation’s disturbance area and lower impact, moving outward from the disturbance. The multipliers are set at specific distances from the mine’s disturbance footprint, as detailed in the table below. For example, the footprint itself has a 100 per cent impact on habitat and RSPF values here are multiplied by 0; distances up to 14 km away have a decreased impact and values in these areas are multiplied by 12.5 per cent to 80 per cent, depending on the distance interval; on the other hand, distances beyond 14 km are considered to have no impact on caribou from the mining operations and, therefore are multiplied by 1 (in effect, values are unaltered). This particular ZOI analysis was based on similar studies (as displayed in the Zone of Influence Table; source of information) showing examples of reduced habitat based on distance from infrastructure—the farther away from the infrastructure, the less the impact on habitat.
The Zone of Influence Table
The Zone of Influence criteria based on distance from the project’s potential disturbance area (PDA)
The result of the ZOI analysis showed the change of scale and amount of habitat selectivity that was directly related to the project. The GIS team leveraged ArcGIS Desktop to perform this calculative process and created a complex set of processing tools in ModelBuilder. These tools allowed the team to run many iterations of the analysis and refine input parameters to get the right results.
On the use of the Raster Calculator tool, Power emphasizes: “Raster Calculator helped us apply the RSPF to the Zone of Influence analysis to understand impacts on the probability of habitat selection by caribou. The purpose of this analysis was to provide us with the means to respond to local community concerns about the project’s impact on caribou and its habitat. First, we were able to define baseline values by quantifying the amount and quality of habitat with the RSPF model. Secondly, we were able to assess the impact of the project by showing baseline values [RSPF] compared to impacted values [RSPF x ZOI].”
Impact of the Mine on Caribou Habitat
Upon concluding the modelling and analyses, EDI was able to quantify the impact of the mine on caribou habitat. The overall effect from the Mary River Project on the home range of the North Baffin Island caribou herd was 1.72 per cent, which is considered within an acceptable range of risk.
EDI used ArcGIS Desktop for all spatial aspects of the project: data management, geoprocessing and analyses. It relied heavily on the Spatial Analyst extension to create inputs, results and process analyses. “Other third-party spatial tools and software were tested,” says Power, “but results from these were often problematic in the sense that they didn’t always give us what we needed or desired. The tools in ArcGIS, more specifically in Spatial Analyst, were dependable, and results were predictable and repeatable—all important considerations when developing and analyzing data of this scientific nature. In the end, we needed a defensible product that would stand up to scrutiny by, not only by our own biologists, but also regulators and other stakeholders – ArcGIS provided us with the means to create that product.”
Nunavut's economy is on the cusp of unprecedented growth spurred by new gold production and the development of new mines. Increased mining production is also expected to help create thousands of new jobs in the coming years. However, to sustain this level of growth, it is equally important to safeguard the natural resources in the region by monitoring any human disturbance caused by mining, construction or related activities. BIM’s Mary River Project serves as an example of how human impact can be accurately identified in such areas and how stakeholders can work together to mitigate those impacts.
This article originally appeared in the Fall 2018 issue of ArcNorth News.