To support our major civil engineering schemes in Sierra Leone, Dawnus operated four Quarries in the country, in Rofayne, Mapathe, Markarie and Wendugu. The Tonkolili quarry produced over 1.6 million tonnes of material for use as sub-base material in roads, railway ballast and aggregates for the production of concrete.
Ballast and aggregate production was processed using our own state-of-the-art crushing and screening plants comprising six jaws, five cone crushers and seven multi split screens with four drill rigs providing our drill and blast capacity. We operated up to five crushing trains in Sierra Leone, supported by a team of plant fitters, quarry excavators, dump trucks, front end loading shovels and a fleet of eight-wheeled road tippers for stone distribution. The quarries processed railway ballast, sub-base, six single-size filter media, concrete aggregates, dust and clean stone for gabions and stone pitching.
The geology of the rock was the most challenging aspect to deal with. The drilling and blasting team has altered the blast design to suit the nature of the rock in each quarry and using GPS surveying have been able to achieve free draining quarry floors where possible.
All stone produced was tested to British and International Standards in the laboratories we have set up at each area of work. Through our experienced team of professional and dedicated expatriate and local staff, we were able to rise to the challenges to ensure our client is provided with high quality ballast and aggregate product on time.