Materials and waste
Most of the materials used in road construction and maintenance – such as asphalt, crushed rock, concrete and steel – are non-renewable resources. However, these materials are highly reusable and are recyclable at the end of their lives. Transurban looks for opportunities to recycle and reuse such materials wherever possible. Across our operational roads and offices, we recycled more than 3,840 tonnes of solid waste (58% of total ‘waste’ material) and sent around 2,755 tonnes (42%) to landfill.
Our largest and most varied sources of waste generation are road development projects and major maintenance activities such as asphalt re-sheeting.
When our development projects are included — which have significant recycling of rock, soil and construction materials — we recycled more than 2,379,000 tonnes of material (99.7%), significantly greater than the 6,766 tonnes (0.03%) sent to landfill.
Regeneration of the Hornsby Quarry began in FY17. Spoil from NorthConnex tunneling will be re-used in the rehabilitation of the 35 hectare quarry – with plans for a community recreational facility to be built on the site by Hornsby Council. More than one million cubic metres of spoil are expected to be delivered to the site from NorthConnex, In FY17, approximately 100,000 cubic metres of spoil had been deposited into the quarry.
The Gateway Upgrade North project successfully completed the first large-scale demonstration of a new type of asphalt in Australia. EME2, a high-modulus (stiff) asphalt designed for use on heavy-traffic roads, has been used in France for more than 25 years. EME2 allows for up to a 20 per cent reduction in the depth of pavements – so less asphalt is needed.
For the Gateway Upgrade North project, we designed, manufactured and placed around 10,000 tonnes of EME2 asphalt along the new southbound lanes of the Deagon Deviation. Using EME2, instead of traditional asphalt, reduced our use of non-renewable resources and lessened fuel use and emissions from avoided truck haulage. The Queensland Government’s Department of Transport and Main Roads will monitor the performance of the EME2 demonstration area over the course of its design life, to assess the potential for using EME2 or combination EME2/recycled asphalt in other projects.
Crushed recycled glass on the M2 Macquarie Park Motorscapes projects
The M2 Macquarie Park Motorscapes project in NSW included significant site preparation to clear and revegetate the area, including earthworks and backfilling of stormwater pipe channels. Sand, a non-renewable resource, is frequently used as backfill in projects such as this – but Transurban opted to trial the use of a recycled resource instead: recycled crushed glass (RCG). The 125 tonnes of RCG we used would equal around 66,000 glass soft drink bottles.
RCG is a safe, Environmental Protection Agency-approved backfill material which reduces the demand for virgin materials sourced from non-renewable sources. The RCG used for the M2 Macquarie Park Motorscapes project site was processed locally in Sydney.