Surface Disposal of Paste Tailings

Underground disposal of tailings as a cemented paste backfill is becoming the state-of-the-art in many mining operations. Paste tailings also constitute a promising solution for surface storage. Due to the higher density and strength of paste tailings, their use reduces some of the risks linked with surface disposal of tailings. The densified state also increases the amount of water being re-circulated at the process plant. Moreover, because of its propensity to retain more water under unsaturated conditions, paste tailings containing sulphidic minerals are less likely to be exposed to an oxidizing environment, which reduces the potential for generation of acid mine drainage (AMD). Presently, the storage of paste tailings in surface impoundments is limited to a very small number of mining operations around the world. Barrick’s Bulyanhulu Mine in Tanzania is considered a pioneer of this technology. This paper presents some of the developments of this technology, and discusses the advantages and limitations of surface storage of paste tailings using the Bulyanhulu Mine experience as a generic case.