THE importance of protecting the quality of South Africa’s groundwater came under the spotlight recently when contamination expert Richard O’Brien from SRK Consulting’s Cape Town office shared compliance lessons with leading industry players at a breakfast seminar hosted by SRK in Port Elizabeth.
Managers and environmental practitioners from the petroleum, automotive and mining sectors – as well as from municipalities and the Department of Water and Sanitation (DWS) – gathered at the event, according to Rob Gardiner, principal environment scientist in SRK’s Port Elizabeth office.
“This was a valuable opportunity for us to share our experience with managers of industrial or commercial land that has the potential to be contaminated,” said Gardiner.
“While the Waste Act has been in force since May 2014, there has been some uncertainty about how it would be implemented. We have interacted extensively with authorities since then and have learnt a great deal that we could pass on to industry and other stakeholders.”
He emphasised that groundwater protection was particularly topical given the drought in many parts of the country, leading to more groundwater resources being targeted for alternative water supply.
“As the number of groundwater users grows, there is the possibility of groundwater abstraction in the vicinity of contaminated land, which is something that owners of that land may not have considered when determining the risks to neighbouring communities,” he said.
“It is therefore vital that the source of contamination, pathways and receptors are comprehensively understood, so that land owners are in a position to decide on appropriate action, including notifying the Department of Environmental Affairs (DEA).”
Je said SRK’s work in the field of groundwater and contaminated land, including its extensive engagements with the DEA, had given its scientists and engineers a clear understanding of ‘significance’ as referred to in the Waste Act. The seminar explored this concept and clarified those cases where the term’s precise application might still be unclear – as in situations where future land use might change the ‘significance’ finding.
“Soil screening values are useful, but are guidelines and not remediation targets,” he said. “Clients need to understand the assumptions that are used to arrive at these values, and their applicability at a particular site; if they do not, the result could be a false sense of security – or alternatively lead to unnecessary remediation costs.”
The seminar also highlighted the importance of understanding the background concentrations on a site – in the soil and in groundwater. The establishment of local background threshold levels, particularly for metals and inorganic anions, is critical in distinguishing between site impacts and natural background concentrations – as these vary as a function of local geology.