Babcock’s supply of heavy construction equipment for construction of an airport on the remote island of St Helena will also be deployed to build a permanent wharf, enabling ships to dock alongside for the first time in St Helena’s history. The island is in the South Atlantic Ocean, 2,000 km from the nearest mainland.
Project director, Basil Read’s Jimmy Johnston, says with 60% of the airport now complete, the equipment supplied by Babcock – primarily Volvo heavy construction vehicles – has performed reliably, with good fuel efficiency and high productivity. Once the airport and wharf have been completed, this equipment, previously unobtainable on the island due to the challenging shipping logistics, will be available for future infrastructure development.
Babcock has supplied the construction equipment in batches, beginning with shipments on the RMS St Helena that included a Volvo EW140C wheeled excavator, a BL61 backhoe loader and a DD24 2.5-tonne double-drum vibration compactor. Since August 2012, Basil Read’s flat-deck shallow-draught cargo ship, NP Glory 4, has brought the balance of the equipment to the island. Other shipments have included a high-discharge two-tonne Winget site dumper and a hydraulically-operated, heavy-duty Winget concrete mixer.
Later shipments brought a Volvo G940B grader, four 70-tonne Volvo EC700 C-Series crawler excavators, one Volvo MC115C skid steer loader and Volvo articulated dumpers with 30- and 40-tonne payloads. This equipment was necessary for more rigorous and heavy-duty site work, and also to undertake the necessary bulk excavation and rockfill most cost-effectively.
The project began with construction of a temporary landing facility at Rupert’s Bay to accommodate the NP Glory 4. In July 2012, the ship was the first ever to unload directly onto St Helena Island. Since then the volume of material shipped reflects the operation’s scale. Around 30,000 tons of cargo has been moved so far, including 500 tons of sand from Namibia, more than 120 items of construction equipment, 900 containers and 1,200 tons of reinforcing steel. By the end of the project, more than 20-million litres of diesel fuel, 5,000 tons of explosives, 27,000 tons of cement and fly ash, and 20,000 tons of miscellaneous cargo, including steel, piping and building materials, will have been moved.
To enable the transport of equipment and material from Rupert’s Bay to the airport site at Prosperous Plain, Basil Read has built a 14-km-long haul road that rises over 500 m in the first 5 km — itself an engineering challenge.
Volvo equipment is being heavily deployed on constructing the airport runway. This involves filling ‘Dry Gut Gorge’ with 8 million cubic metres of blasted rock over 100 m high and 750 m wide, creating an embankment that will form part of the runway. Fill material is sourced from the site area as the landscape and hills are levelled. The Dry Gut fill will take 24 months, with completion scheduled for September 2014.
Work has also commenced on the 1,950-m-long concrete runway, a taxiway and apron. This is due for completion in May 2015. Construction of the terminal building, combined air traffic control and fire department is progressing well and on schedule. Installation of aerodrome ground lighting, navigational aids and air traffic control equipment will begin in August 2014 and be completed and tested by mid-2015. Construction includes a bulk fuel installation for six million litres of diesel, petrol and aviation fuel in Rupert’s Valley and an fuel facility at the airport site.
Environmental protection is guided by Basil Read’s Environmental Management Plan which covers flora, fauna and heritage issues. In addition, Basil Read fully supports the Landscape And Ecology Mitigation (LEMP) programme, a four-year initiative focussing on habitat restoration and landscaping required as a result of the airport construction and supporting infrastructure activities. LEMP will carry on after all construction has ceased and provide alternative habitats and landscape treatments to reduce and offset the permanent direct loss of habitat and the direct and indirect impacts on the landscape from construction.
The airport will finally be connected to the island’s electrical, communications and roads infrastructure and everything will be ready for the first commercial flight in early 2016.
More information from David Vaughan, Tel: +27(0)11 230 7300 / www.babcock.co.za
For more articles such as this one please take a look at our online magazine: http://concrete.tv/more/concrete-trends
