The Yukon Mining Sector: From Planning And Operation To Remediation And Restoration

In response to the increasing vulnerability of the Yukon’s mining industry, this report captures different examples of how the industry had started to adapt to climate change in 2014. For the mining industry in the Yukon, dealing with a rugged landscape and climate extremes has always been a costly part of “doing business”. Historically the industry adapted to known climate extremes, through engineering response, by adjusting operations in concert with the annual seasonal cycle, and through development of flexible but robust transport systems. The symptoms of a changing climate in the Yukon however, have recently been manifest in increased precipitation, permafrost degradation, increased incidence of extreme events, and shifting seasons. Consequent events such as flooding and soil liquefaction have the potential to add to the costs of mining by disrupting mine operations and transportation. In response, this research examines climate change vulnerability and adaptation in three stages in the life of a mine, (i) inception and planning, (ii) operating, and (iii) post-closure (or remediation and restoration) through case studies located throughout the Yukon. The report covers four different mine sites adapting to climate change providing insights on mechanisms to enhance the competitiveness and adaptive capacity of the mining sector in a changing climate.

Understanding and Assessing Impacts

The average annual temperature has already risen by 3°C in the past fifty years, introducing risks and vulnerabilities associated with shifting shoulder seasons, fall freeze-up occurring later and spring thaw earlier, permafrost degradation, changes in precipitation, and an increase in the frequency and intensity of extreme weather events. Information on understanding the risks these changes have on the mining industry were derived from key informant interviews with mine professionals and document analysis. A semi-structured interview guide was employed, and questions were open-ended to allow respondents to describe their experiences and actions from their perspectives and in terms relevant to their expertise. The interview guide was organized around the themes of vulnerability (exposure-sensitivity and adaptive capacity) and adaptation to climate change. The changing conditions have been documented as exacerbating existing vulnerability in the mining industry, particularly surrounding implications for transportation networks, infrastructure, hydrology and operations. This study demonstrates the different impacts and vulnerabilities associated with different stages of a mine’s lifecycle and the types of responses that have been taken.

Identifying Actions

The Yukon’s mining industry has a history of adapting to known climate extremes through engineering response, by adjusting operations in concert with the annual seasonal cycle, and through development of flexible but robust transport systems. However, climate change has exacerbated existing vulnerabilities of the industry, requiring immediate response and action. Adaptation actions were identified through informant interviews. A major element of this study was the inclusion of key informants with practical and applied knowledge, and expertise in the Yukon’s mining industry and the different risks that exist throughout the three life stages of a mine. While this report documented several impacts that are likely rooted in a changing climate, much of the experience has occurred over the past decade, and no mine has experienced such events through its entire life cycle. Therefore, the case studies in the report demonstrate adaptation related to the three different life stages of a mine.

Map of case study locations, Yukon Territory

Map of case study locations, Yukon Territory

Implementation

The type of response to climate risks differed between the life stage of the mine. The informant interviews uncovered that actions have been implemented on an as-needed-basis at each of the included mine sites. The Victoria Gold mine is a new venture currently in the planning and construction phase, introduced into an environment where the possibility of climate change is recognized. Therefore, adaptation and resilience measures have been incorporated into the design and planning phases of this mine site. It is the first mine in the Yukon planned to anticipate events associated with a changing climate through its entire life cycle. In comparison, implementation of actions at the Capstone Resources Minto Mine which was designed twenty years ago, before the mining industry acknowledged that climate change was an issue, has had to reactively respond to a number of climate-induced challenges. Finally, the last mine included in the case study overview exemplifies the challenges of remediating relict mine sites in the context of a changing climate.

Outcomes and Monitoring Progress

One of the key findings of this project was that emerging mines have the opportunity to incorporate climate change prognoses into full life cycle planning, but there is still a great degree of uncertainty on the magnitude of change needed. Existing mines have to address unanticipated climate related problems reactively and as they arise, adjusting closure and remediation plans as conditions change and new information becomes available.

Next Steps

This project highlights the requirement for increased quality of localized climate data for mine sites. By increasing the robustness of climate data, the trends can be translated more accurately into expected local impacts on permafrost, surface hydrology and groundwater. Enhancing his data has been found to be pertinent for all aspects of the Yukon mining industry and is especially important for revising engineering standards.