Project Name: Vissershok Cell 3B
Client: Vissershok Waste Management Facility (Pty) Ltd
Project Description: The Contract comprised the design, site supervision, quality assurance on the geomembrane installation and contract administration of a new cell (Cell 3B) at the Vissershok H:H Waste Management Facility. The Site is situated next to the N7 approximately 30km north of Cape Town CBD.
The layer works for Cell 3B comprised of the following (from top to bottom):
- 300mm thick stone drainage layer of 38mm crushed stone
- 200mm thick sand protection layer on floor and 1000g/m² non-woven geotextile as geomembrane protection layer on the side slopes.
- 2mm HDPE geomembrane (24 000m²)
- 4 x 150mm thick compacted clay layers
- A4 non-woven geotextile separation layer
- 150mm thick sand layer as a leachate leakage detection layer
- Rip and Re-compact 150mm thick in-situ clayey material
Perforated HDPE leachate drainage pipes were installed within the stone drainage layer. These pipes connect to solid wall HDPE drainage pipes at the cell’s low point from where it gravitates into the pump sump. From the pump sump the leachate is being pumped to the new leachate storage area which was also constructed as part of this contract. The new leachate storage area consists of a dedicated 222 kℓ “Botank” that is lined with a 2mm HDPE geomembrane. The leachate storage area is situated in the old mono-sulphur cell that is lined with a 250mm thick clay layer, 2mm mono-textured HDPE and another 250mm thick clay layer on top of the HDPE. The storage area is bunded off by a clay berm designed to provide emergy storage capacity for 4 Botanks (future tanks).
The sand leakage detection layer underneath the layer works is connected to a leakage detection sump which is linked to a detection monitoring pipe next to the pump sump for easy monitoring.
Location: South 33 46 18 East 18 32 06
Contract Data (Construction)
Contractor: Martin and East (Civil), Engineered Linings (Geosynthetic lining work)
Commencement date: 7 April 2005
Completion date: 6 December 2005