Challenges in ensuring stability whilst providing environmental compliance for existing TSFs

Knight Piesold South Africa, Johannesburg, South Africa

^* Corresponding author: ezannoni@knightpiesold.com

Abstract

The stringent requirements for tailings storage facilities (TSF) following the publishing of the Global Industry Standards for Tailings Management (GISTM) have required in depth stability supported by advance testing and modelling, where in the presence of a hazardous tailings facility would require knowledge of the barrier system. Often a buttress is required to increase the factor of safety from the one originally designed, complying with stability as well as environmental requirements, and most importantly without triggering any failure during construction. The paper aim to present a project where the facility requires a buttress as the original design in the early 2000’s was not acceptable in today’s requirements. The stability pivot over a multi-layered barrier system (which does not allow Mohr-Coulomb failure criterion) and the different waste classification between the tailings and the buttress material, requiring different barrier requirements, yet to all be tailored in a constructible solution, without affecting the stability of the TSF.