Background
In October 2015 Downer was awarded a six month $15 million contract to upgrade the Queenstown Airport. This was done to prepare the airport for evening flights starting late May 2016.
Problem
Critical to the project was resurfacing the entire 05-23 runway at varying design depths, averaging 110 millimetres. This process involved milling the existing top, and resurfacing. Downer had to ensure that at the end of each shift, the runway was functional and ready to land aircraft.
The project was exposed to significant safety, health and environmental risks.
Solution
Following investigation of available products for soil stabilisation, Downer proposed the use of Vital Bon-Matt Stonewall as the preferred product solution.
Vital Bon-Matt Stonewall was sprayed on the shoulders each night (at a five per cent concentration) after each night’s earthworks operations. This technique worked particularly well to provide dust mitigation from aircraft engine blast damage in the rotation zone, whilst also stabilising work areas from wind lift.
Downer staff noted Vital Bon-Matt Stonewall also sealed in moisture in the soil, providing the additional benefit of aiding in grass strike when sprayed over the newly sown grassed areas. In addition to stabilising work areas, Vital Bon-Matt Stonewall was also used as a sub-base curing agent; allowing for stabilisation of sub-base material before asphalt was applied directly on top, removing the requirement of bitumen emulsion.
Careful planning, good management and efficiencies resulted in the project being delivered ahead of schedule, on budget and with minimal dust from the work areas. The sustainable qualities of the Vital Chemical soil stabilising range also supported the environmental outcomes of the project.