Increasingly hemmed in by urban development, AfriSam’s Jukskei quarry and readymix plant have been applying ever more stringent controls and standards to remain a friendly neighbour.
When the Jukskei quarry began operation some seven decades ago, its location was decidedly rural. However, the surrounding area of Midrand developed rapidly, and in the last 10 to 20 years in particular, various neighbours have closed in around the Jukskei aggregate and readymix operation.
“Today, we are surrounded by residential, commercial and industrial developments,” Zielas Du Preez, regional manager for AfriSam’s Gauteng Aggregates Operations, says. “This process, alongside the changes in environmental regulations, means that we are constantly improving the way we work.”
Noise, dust, blasting and water quality are among the most important areas of focus. To minimise the impact on surrounding areas, noise monitoring is regularly conducted. Measuring points around the operation feedback information on how noise is being dissipated. The data populates an annual survey against which performance can be checked.
With the crushing of blasted granite into various aggregate products, and the constant movement of trucks and other equipment, dust is inevitable. A number of strategies to control dust are applied, Du Preez says. These range from sprays inside the high speed crushers, activated on start-up, to water spray systems along the roadways to suppress air-borne dust.
This success is measured with the monthly analysis of Dust Fallout Buckets, strategically placed in numerous positions around the operation. The collection and analysis of these buckets are performed by an independent consulting group.
Monitoring of water quality is also critical, both upstream and downstream of the pit. This is done at seven sample points, ensuring that any seepage from the quarry is not negatively affecting water quality.
Controlling blasts in the quarry leverages the latest technologies to keep noise, vibration and other impacts low. He notes that electronic blasting has revolutionised the quest for more effective and better controlled blasts.
“Using electronic blasting technology and blast planning software, we can simulate each blast within optimal parameters,” he says. “We keep air blast, vibration and fly rock to a minimum, while still achieving our required fragmentation for the crushers.”
There is even a public engagement element to the blasting programme, where neighbouring properties are kept informed through a roll-call list. In pursuit of safety, AfriSam also engaged with the Helipad next door to declare the quarry area a no-fly zone during blasting.
Du Preez highlights that extra security measures have been applied in the quarry, including lighting and surveillance– as human settlements encroach ever closer.