Sustainable design of tailings dams using geotechnical and geomorphic analysis

Abstract

ABSTRACT Geomorphic landform design for mine waste structures has been proposed as a sustainable alternative to traditional design approaches for decades. Over this time, the focus on mine closure and related sustainability approaches has grown steadily. Many geotechnical engineers and responsible mining companies understand the obligation to design and construct structures that will perform well in the long term. Concepts and tools are provided in this paper that will assist engineers in achieving their long-term goals. This research evaluates four tailings dam designs in terms of their geotechnical stability and long-term geomorphology: two traditional designs (uniform slope and platform-bank) and two geomorphic-inspired designs (catena and horseshoe). All four designs were subjected to two- and three-dimensional (3D) stability analysis, as well as 3D landscape evolution modeling (geomorphic analysis). Results indicated that the horseshoe-style geomorphic tailings dam design performed better than the others for each of the analyses completed. The horseshoe design consisted of interspersed catena slopes and uniform slopes, which resulted in a type of buttressing effect that enhanced the geotechnical stability of the dam while also reducing and focusing surface erosion.