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ARD risk management is not just a matter of geology, chemistry and engineering. Dave Richards, project manager for development of Rio Tinto's ARD strategy, puts it this way: "As much as anything, it's a an organizational issue. ARD can emerge as a risk in all parts of the project cycle, from exploration to mine closure and beyond. A lot depends on whether everyone is alert to the risk, whether they use the right evaluation methods to assess the risk accurately, and whether there is determination in the top management of projects to cope with it."

It all has to start with recognition that there are ARD hazards at individual sites and that they give rise to specific risks. There is no point in using resources to prevent something that isn't going to happen. On the other hand, where ARD is inevitable or likely, it makes sense to gear the response to the probability of serious consequences.

The correct response can only be learnt from site-specific research. Where ARD has not yet started, the aim of the research is to spell out how it can be prevented. The next step is to give mine planners and managers knowledge tools that will allow them to control ARD. The aim of last resort is to identify techniques that will reduce ARD impact, especially those on lifeforms and their support systems, to an acceptable minimum.

Dave explains what's involved. "First we must take stock of what's already known. Many questions have to be asked and answered. Some look far into the future: how much waste rock of each type will be produced over the life of the mine, when and from where? Some sound a lot simpler to answer than they actually are, like how much rainfall is going to infiltrate the waste dump. Many are highly technical, relating to such things as the expected availability of air inside the dump and the processes that will promote ARD and disperse its products.



ARD risk management is not just a matter of geology, chemistry and engineering. Dave Richards, project manager for development of Rio Tinto's ARD strategy, puts it this way: "As much as anything, it's a an organizational issue. ARD can emerge as a risk in all parts of the project cycle, from exploration to mine closure and beyond. A lot depends on whether everyone is alert to the risk, whether they use the right evaluation methods to assess the risk accurately, and whether there is determination in the top management of projects to cope with it." It all has to start with recognition that there are ARD hazards at individual sites and that they give rise to specific risks. There is no point in using resources to prevent something that isn't going to happen. On the other hand, where ARD is inevitable or likely, it makes sense to gear the response to the probability of serious consequences. The correct response can only be learnt from site-specific research. Where ARD has not yet started, the aim of the research is to spell out how it can be prevented. The next step is to give mine planners and managers knowledge tools that will allow them to control ARD. The aim of last resort is to identify techniques that will reduce ARD impact, especially those on lifeforms and their support systems, to an acceptable minimum. Dave explains what's involved. "First we must take stock of what's already known. Many questions have to be asked and answered. Some look far into the future: how much waste rock of each type will be produced over the life of the mine, when and from where? Some sound a lot simpler to answer than they actually are, like how much rainfall is going to infiltrate the waste dump. Many are highly technical, relating to such things as the expected availability of air inside the dump and the processes that will promote ARD and disperse its products.
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Review is published by Rio Tinto, 6 St James' Square, London SW1Y 4LD, England Telephone +44 (0)20 7930 2399 Editor: Cherry DeGeer