INVESTIGATING THE EFFECT OF CEMENT STABILIZATION ON A SLATE WASTE ROCK

Abstract

Acid-producing waste rock is a by-product of urban construction, and its environmental impact necessitates proper disposal. Cement solidification and stabilization is a technique to limit the effect of acid drainage leaching from waste rock material and consists of mixing the waste rock with a cementitious binder, followed by placement in a containment cell. This technique aims to reduce water flow through the material and to increase the pH/decrease effluent contaminant concentrations. Many test methods are available to assess the performance of the stabilized material. Humidity cell testing weathers the treated material over time by repeatedly exposing the stabilized mixture to cycles of air and water. Based on humidity cell testing performed, the cement stabilization was effective in neutralizing the pH of the effluent leachate and slowing the release of most contaminants. Notable exceptions were sulfur and sulfate, which were detected in higher concentrations in the binder treated samples.