Abstract
Mineral resource depletion drives the need for mining in increasingly remote areas using novel methods. Severe conditions in these remote areas can include permafrost. The Chidliak diamond mine of DeBeers situated in the Arctic circle is one such operation. There are many challenges to Arctic mining projects such as transportation limitations and severe climate conditions. Furthermore, the Chidliak mine has been planned to have the lowest possible carbon footprint. The mining operation applies a novel vertical boring technique into an open pit, by which the vertical kimberlite pipe with a diameter of approximately 125-150 m will be excavated. Each boring operation results in a vertical shaft, having a diameter of roughly 5 m that is subsequently backfilled. Design of the backfill while considering the mine and environmental limitations is the first step of this study. Cement or binder is omitted from the backfill mixture due to the transportation cost and the adverse effect of low temperature on cementation. Alternatively, frozen backfill in which water plays the role of binder will be used. In order to use this novel, backfill, the thermal behavior and freezing time of backfill will be investigated and discussed in this paper.