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A life cycle assessment (LCA) was performed to determine the global warming impacts of nickel mining in the Arctic and to compare the life cycle greenhouse gas emissions of nickel mining with and without the use of wind energy for electricity. The functional unit for this LCA was the refined nickel produced over one year of nickel mining activities at a model mine. The foreground process chain consists of mining the nickel ore, beneficiation to produce a nickel concentrate, transport to a smelter, smelting, transport to a refinery, and refining to a Class 1 nickel product . Life cycle inventory data for these processes was obtained through databases available from the SimaPro 7.3.3 software, through peer-reviewed sources, and through calculations based on the nickel mining activities associated with the Raglan mine operated in Nunavik by Xstrata Nickel. An existing life cycle inventory for a Class 1 nickel product was modified so that all electricity originated from 600 kW wind turbines. Surface mining was determined to disturb 0.0018 m2 per kilogram of nickel ore, and underground mining was found to disturb a net 0.00076 m2/kg nickel ore (Ecobalance, 2000). The greenhouse gas emissions associated with land use change were determined separately from the rest of the life cycle of nickel mining. Two main sources were considered for land use change-related emissions: the change in atmospheric carbon dioxide assimilated into biomass production and the change in nitrous oxide emitted from permafrost as it is disturbed and undergoes melting. The net primary productivity (NPP) change on disturbed land was used to determine the carbon dioxide emissions associated with implementing new nickel mining. The carbon dioxide equivalents of nitrous oxide released from disturbed and thawing permafrost were also calculated using the IPCC potency factors (Intergovernmental Panel on Climate Change, 1996) and nitrous oxide flux measurements from a permafrost thawing experiment (Elberling et al., 2010). Mineral exploration and the development of mines to extract metals such as nickel is expanding in Arctic regions. Renewable energy projects are occasionally proposed along with mining development as a way to reduce the environmental impacts of new mines and their associated infrastructure. The greenhouse gas emissions from mining, transporting, and refining metals could be offset from the use of wind power, for example, but it is unknown to what extent this substitution of renewable energy for conventional electricity generation affects the climate change impact of producing a refined metal product from mined ore. The greenhouse gas emissions from these activities are of particular importance for Arctic regions, which experience the effects of climate change more severely than other parts of the world and where indigenous peoples’ way of life is increasingly affected by climate change. A life cycle assessment (LCA) of the coupling of wind energy and nickel mining in the Arctic was performed to determine the life cycle greenhouse gas emissions of these projects, including emissions from land use change. Life cycle assessment is a method that evaluates the potential environmental impacts of a process or product system over its life cycle. Among other uses, life cycle assessments and LCA methods have been used internationally to guide government policy (Curran, 1997). The Kativik Environmental Quality Comission, the official body involved in assessing social and environmental impacts of development projects for regions in Québec including Nunavik, has called for the use of life cycle assessment for such pursuits: “In the future, the use of strategic planning tools--to review Nunavik-wide development proposals, such as in the mining sector—should be carefully considered. The integration of life cycle assessment with the environmental impact assessment process would help to increase our understanding of the long-term justification of projects in the North” (Jacobs, Berrouard, & Paul, 2009). Climate Change and Human Impacts of Renewable Energy and Mining Development in Arctic Regions Marie-Odile Fortier C-CHANGE IGERT Fellow and Environmental Engineering Doctoral Student at the University of Kansas Introduction Case Study: Nunavik, Québec, Canada Methods Conclusions Results and Discussion Acknowledgements http://www.ledevoir.com/plan-nord http://www.infomine.com/minesite/minesite.asp?site=raglan Toffoletto et al. 2007, International Journal of Life Cycle Assessment 12 Liu et al. 2002, Global Ecology & Biogeography 11 Mining Beneficiation Transport to Smelter Smelting Transport to Refinery Refining Nunavik comprises the northern part of Québec, Canada. The vast majority of its population is Inuit and resides in 14 villages. The land is categorized under the James Bay and Northern Québec Agreement. Nunavik is one of the regions that will be affected by the Plan Nord, an $80 billion government project which involves developing hydropower, wind power, tourism, metal mining, transportation, telecommunication networks, education, healthcare, and housing infrastructure north of the 49th parallel in Québec. There are mixed responses to this proposed development, including concern about the potential environmental impacts. In Nunavik, two companies are planning to establish new nickel- copper mines, including a second phase to the Raglan nickel mine. http://www.xstratanickel.com/EN/Operations/Pages/Raglan.aspx http://www.infomine.com/minesite/images/raglan9.gif The Raglan nickel mine was the model mine used in this analysis. The Raglan mine produces 1.3 million metric tons of nickel ore annually and processes this ore on site to 26,000 metric tons of nickel-in-concentrate (Xstrata, 2011). This nickel-in-concentrate is transported over 5600 miles to be refined into Class 1 nickel. These transportation processes were modeled in this LCA. The northern half of Nunavik where nickel mining is proposed is characterized by two ecozones: Northern Arctic and Southern Arctic (Liu et al., 2002). In the Northern Arctic, the average NPP is 0 ± 2 g C/m 2 /year, whereas the average NPP for the Southern Arctic ecozone is 15 ± 24 g C/m 2 /year. The annual greenhouse gas emissions from nickel mining in Nunavik and subsequent processing are 209,000 metric tons of CO 2 equivalents, without land use change impacts. The use of wind energy reduces greenhouse gas emissions by 32%, thus preventing nearly 100,000 metric tons of fossil carbon dioxide from entering the atmosphere yearly. However, this reduction depends on all electricity being produced from wind, including at the refinery and smelter that are typically located far from the mine site. The vast majority of the climate change impact is mining and processing. Less than 2% of greenhouse gas emissions are attributed to transportation, but due to the tons of nickel transported over thousands of miles, these emissions are still substantial at 3450 metric tons of carbon dioxide equivalents annually. Land use change can contribute between 181 and 558 metric tons of carbon dioxide equivalents per year depending on mining conditions (surface or underground) and mine location (Northern Arctic or Southern Arctic ecozone). Though this land use change impact is hundred of metric tons of carbon dioxide equivalent, it is only a fraction of a percent of the total life cycle greenhouse gas emissions for nickel mining and processing. Along with the small transportation emissions relative to the total greenhouse gas emissions for nickel mining and processing, this indicates that the location of a Nunavik nickel mine may not play a significant role in the total climate change impact of its associated processes, although other environmental impacts could be affected by the site of a mine (e.g. biodiversity impacts, if a mine is located close to or within a critical habitat for an endangered species). The total life cycle greenhouse gas emissions for a model Arctic nickel mine’s associated activities in the production of refined nickel are equivalent to those of 40,000 passenger vehicles despite the use of a renewable source for electricity (United States Environmental Protection Agency, 2011). The author thanks professors David Braaten, Sharon Billings, Jay Johnson, and Joane Nagel at the University of Kansas, as well as our hosts and colleagues in Greenland. The author also thanks NASA EPSCoR #SUB3138-17 and the C-CHANGE IGERT program at the University of Kansas. The use of wind energy causes a substantial decrease in the life cycle greenhouse gas emissions from nickel mining in the Arctic and subsequent beneficiation and processing. However, the process of mining and refining nickel has significant climate change impacts even when wind energy supplies all electricity needed in the life cycle of nickel. It is prudent to consider the long term future of Arctic residents in the face of climate change and the scale of the potential increases in greenhouse gas emissions over the life cycle of proposed mining projects. Life cycle assessment is a useful tool in determining the relative environmental impacts of processes in a proposed development project; in this case, LCA showed that land use change and transportation did not contribute more than 3% combined to the overall climate change impact of nickel mining and processing. The implications of LCA results can help to guide policy as they reveal to what extent changes in a production system alter its overall environmental impacts, like the source of electricity (significant change in greenhouse gas emissions) or where to site a mine and whether to develop a surface or underground mine (relatively small change in life cycle greenhouse gas emissions).
