Nahir, M, O'Kane, M & Ayres, B 2011, 'Development of a technical guidance document for cover system design in cold regions', in AB Fourie, M Tibbett & A Beersing (eds), Mine Closure 2011: Proceedings of the Sixth International Conference on Mine Closure, Australian Centre for Geomechanics, Perth, pp. 503-511, https://doi.org/10.36487/ACG_rep/1152_53_OKane (https://papers.acg.uwa.edu.au/p/1152_53_OKane/) Abstract: The Contaminated Sites Programme of Indian and Northern Affairs Canada (INAC-CSP) is responsible for closure of contaminated sites on Crown land throughout the Canadian North. A significant percentage of the closure liabilities faced by Indian and Northern Affairs Canada (INAC) is associated with abandoned mines. Of these mine-related liabilities, at least one third involve the need to construct earthen cover systems over potentially reactive tailings and waste rock. INAC will be implementing cover systems at some sites in the very near future and therefore requires information on key physical, chemical, and biological processes that may affect long-term risk to these cover systems. This paper describes the technical guidance approach for cover systems in cold regions that is being developed by INAC with the assistance of a Technical Advisory Group (TAG). The focus of the paper is on the cover system design philosophy including the need to develop site specific closure objectives and criteria, mine closure planning and progressive reclamation, utilising attributes of cold regions, designing for sustainability, importance of final landform design, and assessment period and design life.