With the continued implementation of stricter limitations on the discharge of excess process water from all existing and future mining and metallurgical operations, the design and operation of the entire process water circuit must form an integral part of any total operational package. It is far better to anticipate and circumvent the problem' rather than be forced into an expensive remediation program after the event. By far the greatest problem relates to the treatment and disposal of what is generically known as acid drainage._x000D_
In simple terms, an acidic metal sulfate solution is generated by a series of chemical and biological reactions as soon as most sulfide minerals are exposed to air and water. Treatment of this solution by one or more of a wide range of chemical and physical options can involve substantial capital and operating costs, although there are recent processing options that yield saleable by-products, thereby reducing the financial liability of what is effectively a waste stream._x000D_
This presentation provides an overview of the Australian situation compared with the rest of the world and outlines the basic features of a number of the more advanced passive and active acid drainage options._x000D_
FORMAL CITATION:Canterford, J, 2004. Designing processing operations for the future - don't forget acid drainage, in Proceedings Metallurgical Plant Design and Operating Strategies 2004, pp 261-268 (The Australasian Institute of Mining and Metallurgy: Melbourne).