Leading South Africa-based, black-owned contractor Concor is engaging on a 17-month project to construct a new pollution control dam at De Beers’ Venetia diamond mine, South Africa’s largest diamond producer.
The well-advanced Venetia Underground Project (VUP) will extend the mine’s life span to at least 2045, and the new dam – Pollution Control Dam 3 (PCD3) – is the main containment facility in its Storm Water Management Project (SWMP). The SWMP is a key part of the mine expansion, ensuring compliance with the Government Notice R704 on the protection of water resources, preventing the possibility of flooding and ensuring the safety of people working in the new underground mine.
Concor Operations Executive, Christo Schoeman, explains that PCD3 will cover some 27 ha to the west of the mine and will be constructed to a maximum height of 13 m. This will equip the facility to hold over 1 million cu.m of water. The water will emanate from upstream catchments including runoff from the adjacent coarse residue deposit and fine residue deposit, as well as potential overflow from the other upstream water containment facility. It will also contain water that has been pumped out the of mine’s open-cast pits and the VUP underground workings.
“Zero harm to our employees and the environment whilst executing our projects remains our principle objective,” Schoeman says. “In order to prioritise these endeavours and ensure that construction work does not impinge on the mining operation itself, among the first tasks required will be to secure the works by installing a new security fence, and upgrading the existing access road to our temporary site facilities which will ensure optimised access to our site and help streamline our workflow.”
As part of the bulk earthworks operations, the topsoil over the dam area will be stockpiled during the excavation operations, to be used later for slope protection and to ensure the regrowth of flora once construction is completed.
“In line with environmental requirements and legislation, the excavated structure will be lined with am HDPE geomembrane to prevent any seepage into the groundwater system,” he says. “A specialised service provider will supply and install the lining.”
Concor’s scope of work includes the construction of a pump station and dam spillways, as well as the installation of a 2.5 km return water pipeline to the mine’s processing plant. This will allow significant volumes of water to be efficiently recycled and re-used in processing, it says.
Schoeman highlights that the project contains a strong local procurement, employment and skills development component. He notes that Concor has always been committed to local enterprise and skills development initiatives in the areas where it undertakes projects.
“We are working closely with our client to source general workers and suppliers locally, who we will, where necessary, upskill with training, supervision and mentoring,” he says. “Certain aspects of the project can be subcontracted to these local enterprises, following the systematic process of identification and engagement.”
Concor supervises the work of subcontractors closely as part of its enterprise development commitments, he notes. Combined with dedicated mentoring, this ensures not only a quality outcome in each deliverable, but also higher levels of sustainability amongst subcontractors once the project is complete.