Formerly Mulgoa Quarries
The project involved acting as the principal contractor to deliver the development from a greenfield site through to fully serviced industrial facilities, including the construction of 6.5 kilometres of paved roads. Works required the movement of approximately 2 million cubic metres of material and the completion of night-soil remediation works to prepare the site for development.
This major civil and environmental works project involved the transformation and rehabilitation of a large-scale site through extensive earthworks, drainage infrastructure, water-quality systems, retaining structures and landscape works. The project commenced with the clearing and preparation of more than 42,000m², followed by approximately 30,000m³ of cut-to-fill earthworks to reshape the site and establish the foundations for the downstream civil and drainage infrastructure.
A significant focus of the project was the delivery of resilient stormwater and environmental infrastructure, including approximately 1,200m of stormwater drainage, multiple engineered bioretention basins and associated water-quality treatment systems. The project also incorporated 1,200m of sandstone log and stacked rock retaining walls, designed to provide long-term stability across the reshaped landscape.
The final stage will see approximately 50,000m² of landscaping works, including jute matting, mulching, seeding and turfing, alongside the installation of 120,000 plants and 500 trees. Together, these works will deliver a significantly upgraded and more resilient site, with improved stormwater capacity, advanced pollutant reduction, stabilised landforms and extensive environmental rehabilitation.
The project commenced with extensive site establishment and early works, including the clearing, grubbing and removal of vegetation, debris, structures and unsuitable materials across more than 42,000m². Existing drainage infrastructure was also rehabilitated, widened and replaced, with areas subsequently reinstated using topsoil.
Bulk earthworks involved approximately 30,000m³ of cut-to-fill across all material classes, alongside excavation for bio-basins, swales, channels and structural elements. The works also included preparation of subgrades to support the downstream civil and drainage infrastructure.
A comprehensive stormwater and drainage network was delivered, incorporating approximately 1,200m of stormwater infrastructure across a range of systems, including reinforced concrete pipes (RCP), stormwater pits, culverts and spillways. These works were designed to improve the site's overall drainage capacity and resilience.
Multiple engineered bioretention basins were constructed as part of the project's advanced water-quality infrastructure. These systems incorporate layered filtration media, transition layers and drainage aggregate, together with HDPE liners protected by BIDIM geotextile and extensive subsoil drainage networks. The works also included precast surcharge pits, outlet pits, inlet pits and collection pits, as well as rock outlets, flow control structures and hydraulic conductivity treatments to support effective water management and pollutant reduction.
The project included the construction of approximately 1,200m of sandstone log and stacked rock retaining walls, comprising retaining walls RW1–RW5. These structures incorporated excavation, drainage, geofabric, waterproofing and structural detailing to provide long-term stability and performance across the site.
A major landscaping and site finishing package will transform and rehabilitate the broader landscape, incorporating jute matting, mulching, seeding and turfing across approximately 50,000m². The works will also see the installation of 120,000 plants and 500 trees, alongside stabilisation of batters, swales and basin areas to support long-term environmental performance and site resilience.
On completion, the project will deliver a fully upgraded stormwater network with increased capacity and resilience, supported by advanced water-quality systems designed to significantly reduce pollutant loads. The site will feature a reshaped and stabilised landscape engineered for long-term performance, together with safe and durable accessways and pavements to support ongoing maintenance and operational requirements. Extensive planting and environmental rehabilitation will also deliver a visually transformed site, creating a more resilient and sustainable landscape.
