SASOL FINE ASH DAM 6
BULK EARTHWORKS
With the existing waste storage facilities at Sasol’s disposal reaching capacity, the construction of the Fine Ash Dam 6 was required in order to create additional volume for the storage of the waste being generated. Situated southwest of the Sasol 2 Plant in Secunda, Mpumalanga; WBHO was awarded a string of construction projects from the Enabling Works of the site to the completion of the first HDPE lined waste storage facility for the Client. This 5-year Mega Project was constructed in phases designed to allow waste storage access to the client as the works progressed. Leading up to the construction of the main dam facility, an access road network including the construction of a cross-over bridge across a provincial road had to be built. The trades required for completing the full scope included Civil, Mechanical, Electrical and Instrumentational expertise in order to commission the facility. The dam infrastructure consists of a main ash dam for taking delivery of waste slurry and a drainage system for accumulating reusable water into return water dam for transference back to the operations plant. The main dam consisted of 1 200 000 cubic meters earthworks forming the dam embankment and the basin stretching over 1 600 000sqm of HDPE liner. The return water dam covers just over 200 000sqm of liner and has a capacity of 850 000 kilolitre of water. 24 000 cubic meters of concrete was required to construct the various elements of which the main contributors were the pump station, two 40m high penstock towers and the effluent canal. The mechanical team installed a total of 36 km of steel pipe including 32km of slurry delivery (10″ pipe) and the return water line, 2km long (32″ pipe). The two penstock towers decant into 2km of 40″ clear ash effluent pipes.