SIMULATION OF SALT MIGRATION IN AN OIL-SHALE DUMP SUBJECT TO NATURAL RAINFALL

A solute transport model is presented that predicts the inorganic comp osition of leachate from solid wastes produced by the mining and proce ssing of Rundle oil shale. The model can predict leachate compositions from each of the main categories of waste (i.e. overburden, interburd en and shale ash) and also simulate leachate from mixed and layered ar rangements of waste material. Salt migration under unsaturated conditi ons is handled by interfacing the solute transport model with an unsat urated flow model or experimentally measured moisture content profiles . Laboratory and field experiments were used to provide input data and validate the solute model.