Thermal and physical properties of candidate buffer-backfill materials for a nuclear fuel waste disposal vault

As part of the Canadian Nuclear Fuel Waste Management Program, Ontario Hydro has, over several years, conducted research into the behaviour and performance of buffer-backfill for the proposed nuclear fuel waste disposal vault. In this paper, a review has been made of laboratory studies made at Ontario Hydro on the thermal properties, strength, hydraulic conductivity, and compactability of clay-based buffer materials. The results of this work have enabled the formulation of selection criteria for the buffer material mix for the prototype Canadian nuclear fuel waste disposal scheme