Gélinas, L-P & Alcott, J 2023, 'Arctic backfilling: challenges and lessons-learned', in GW Wilson, NA Beier, DC Sego, AB Fourie & D Reid (eds), Paste 2023: Proceedings of the 25th International Conference on Paste, Thickened and Filtered Tailings, University of Alberta, Edmonton, and Australian Centre for Geomechanics, Perth, pp. 199-212, https://doi.org/10.36487/ACG_repo/2355_14 (https://papers.acg.uwa.edu.au/p/2355_14_Gelinas/) Abstract: Backfill is an inherent component of the mining at Agnico Eagle Mines’ (AEM) arctic operations in Canada, Nunavut, including Amaruq, Meliadine and Hope Bay. Backfill quality is essential to limit the dilution during the mining of secondary stopes and to optimise the mining sequence in this cost-challenging environment. Backfilling with cemented rockfill (CRF) or cemented paste backfill (CPB) in Canadian Arctic conditions is demanding since many assumptions and experiences acquired in warmer temperatures are no longer applicable. Through innovative laboratory techniques, in-situ monitoring and operational lessons learned, AEM operates with various backfilling techniques adapted to the Arctic environment. Keywords: Cemented Rockfill, cemented paste tailings, arctic, permafrost, compressive strength, in-situ monitoring