Speaking at a conference hosted by global environmental engineering consultancy Golder Associates, Gerhard van der Linde said it is vital for companies to understand the individual characteristics of the environment in which they operate. The conference was designated to address issues pertaining to the environmental obligations that fall within the ambit of mining companies operating in South Africa.
The aim of the presentation, which was entitled “Going Beyond Phase 2 Site Assessments”, was to stress the point that no two pieces of land are the same. So in order to effectively deal with contamination, the term first needs to be defined within the context of the land and waste being studied. This is broadly referred to as Phase 1 of the process.
“The idea of Phase 1 is to develop a conceptual understanding of the site and how material moves through it. It also serves to establish the type and magnitude of risks that exist,” says Van der Linde. “It’s a precursor to establish whether the company has acceptable or unacceptable risk,” he continued.
Once the risks have been identified and found to be unacceptable, Phase 2 entails detailed site characterisation to be able to make decisions on what type of remedial action needs to be taken. “When we talk about going beyond Phase 2, what we mean is that it’s vital to take a multi-disciplinary approach to be able to develop a Source-Pathway-Receptor (SPR) model,” says Van der Linde. This entails relying on the conceptual models that science provides, but also taking it a step further.
Around the underlying process involving SPR, practitioners need to do their homework on contextualising the area being studied. “To make these management decisions, you must understand the migration of the contaminants, and to do that you really need to understand the environment – sources, surface water, unsaturated flow, hydrogeological and ecological – to be able to provide an effective solution,” he says.
To reinforce his point, Van der Linde presented a number of case studies. One of them involved a fluoride contaminant that had managed to penetrate the groundwater. “This was due to the fact that the shallow clay that was presumed to have captured the fluoride was not continuous. So you need to make sure you are monitoring the right things.” In another example, a fault had caused contamination in an area no-one had expected to find it.
These all served to underline the key point Van der Linde was trying to drive home. “While the conceptual framework is sound, you need to have a transdisciplinary science with which to approach the problem. By understanding and contextualising the environment being studied, you afford the scientific method more precison and detail, which will surely lead to more effective outcomes.”
The video below features five questions with Van der Linde on his presentation:
This article forms part of an education series sponsored by Golder Associates on the risks industry faces.