B&E International is continuing its long-standing relationship with the Department of Water Affairs after winning the contract for the supply of all aggregates to the De Hoop Dam scheme.

The dam, which has a planned capacity of 300 million cubic metres, is the 14^th largest in South Africa, and the project – which began in 2008 and was concluded in 2011 – was the second-biggest in the company’s history.

According to Royden Webster, B&E International’s director of operations, the task was not without its challenges, especially in light of the complex geology prevalent in the region.

“The topography was very brown and soft, and we had to remove more than 1.2 million cubic metres of overburden to a depth of 17 m to expose the material required for aggregate production. To do the job in the shortest possible time we brought in a 385 excavator and four B40s to remove the overburden and poorer quality material, and by November we were able to assemble and commission the crushing plant,” says Webster.

With construction poised to begin, the timing was perfect for B&E International to commence the production of 120 000 tpm.

The plant included nine crushers, three Hydrasander washers, three washing screens and five dry screens, all linked by a complex but efficient network of conveyors.

Local geological conditions again caused some initial production problems owing to the variable quality of feed coming from of the quarry.

“We had to constantly change crusher settings and alternate screens to stay within specification. However as our production increased we were soon able to grow stockpiles to take the pressure off,” explains Webster.

The urgency may have eased but output was prodigious. During the project life cycle, B&E International produced nearly two million tonnes of aggregate and over a million tonnes of high specification <4 mm washed sand, all of which went into the construction of the dam wall.

In addition, its quarry supplied a further 87 000 t of G1 material for the construction of the R555 by-pass around the dam. By the end of the operation, the quarry footprint, which will soon be under water, extended a massive 400 X 250 m.

This high level of productivity also helped the national water regulator to stake its own claim to fame by pouring over 133 000 m³ of concrete in 28 days, a new South African record.

“B&E International was one of our most reliable and honest sub-contractors, with a ‘first-time right’ approach. Aggregate was delivered on time and within specification,” says Department of Water Affairs’ design representative, Jaco van Niekerk.

The dam is located near Steelpoort in the water-stressed Sekhukhune region of the Limpopo Province.