The acceptable rate of rise of the tailings beaches on upstream-raised tailings storage facilities (TSFs) is critical to life of mine planning._x000D_
This is illustrated through a case study in Western Australia presented in this paper._x000D_
Accurate estimates of expected beach slopes, the maximum rate of rise at which the tailings can be placed, and the dry density that the tailings solids will achieve after deposition (stored density) are required in order to design TSFs that will allow upstream raises to be constructed safely and economically._x000D_
Where operations have been occurring for some time, these three parameters are able to be measured and can be well-defined._x000D_
If process plant throughputs are proposed to increase through mine expansion, for example, increasing the rate of rise of the tailings can compromise the potential for upstream TSF raising, thus influencing the viability of such an expansion, the timing for its implementation, and significantly increase costs.This paper outlines how rate of rise can be a key constraint, and that rules of thumb' that are typically applied may not result in the outcomes they were meant to achieve._x000D_
An example of an experimental method to justify an increase to the rule of thumb' ~2.5 m/year limit for gold tailings in a semi-arid climatic setting is discussed, followed by rate of rise modelling that ultimately framed the decision-making process for a mine expansion._x000D_
The rate of rise modelling method was adopted to carefully distribute tailings deposition across four TSFs, comprising nine separate tailings cells, in order to maintain appropriate rates of rise._x000D_
The implications resulting from various deposition splits are presented, including the need for expansion._x000D_
In addition, this paper outlines the effect of rate of rise on the state (density) of the tailings after deposition, and provides commentary on how anecdotally acceptable rates of rise, based on the aforementioned rule of thumb' of 2.5 m/year may not provide assurance of geotechnical stability through the tailings achieving a dilative state, as has been thought in the past._x000D_
An example of the influence of rate of rise on the state of the tailings, with respect to air-drying and the critical state line (CSL) for the material, is presented._x000D_
The data indicate that reducing the rate of rise may allow a higher dry density to be achieved through air-drying (evaporative desiccation), sufficient to move the material from the contractive to the dilative zone (i.e. from above the CSL, to sufficiently below it).CITATION:Chapman, P J and Williams, D A, 2018. The importance of rate of rise in life-of-mine planning of an upstream raised tailings storage facility - a case study, in Proceedings Mine Waste and Tailings Stewardship Conference 2018, pp 350-360 (The Australasian Institute of Mining and Metallurgy: Melbourne).