1. INTRODUCTION Sand for tailings dam construction “The Global Industry Standard on Tailings Management strives to achieve the ultimate goal of zero harm to people and the environment with zero tolerance for human fatality.” Tailings dams should be of a robust design taking consideration of the risks and consequences of their construction with well proven construction methods. One generally accepted construction material is the sand extracted from the tailings; to be an acceptable building material the sand must be compactable to a minimum density that will achieve the necessary structural strength and to have good drainage properties. Due to the nature of generating and transporting the sand its initial saturation will be high and this needs to be reduced and controlled as saturation of the sand is as one of the greatest dangers for stability. While the sand itself must have an acceptable drainage property, a base drainage is required to remove excess water, and the structure needs to be controlled and measured to ensure the piezometric levels in the dam are at a safe level. Governance of tailings dam management is increasing and while it is the operators of TMFs that have the primary responsibility for ensuring the safety of TMFs and for formulating and applying safety management procedures, as well as for utilizing technology and management systems to improve safety and reduce risks. The methodology of producing a construction material has inherent risks and quality is measured post deposition. An alternative and fundamentally lower risk methodology would be to deposit the sand with the optimum water content for compaction. Tailings storage facilities (TSFs) represent one of the most critical challenges due to their potential environmental impacts, high water inventories, and long-term stability concerns. GISTM is driving change to improve the safety and efficiency of tailings storage. Sand properties The sand must be a competent material and as its origins are the ore mined it will have geological properties defined by the host rock. The mining process is designed to recover valuable minerals; the ore will be crushed and milled to liberate this value defining the size of the tailings. The generally acceptable definition is for the sand to have a grain size greater than 75um with no more than 15% of the mass passing 75µm, examples of higher levels of fines up to 18% are cited. In part the requirement is driven by the permeability of the sands, with clays and particles below 20 μm being particularly detrimental. Fines also impact the void fraction filling the voids,
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