Greenbushes Chemical Grade Plant 3 (CGP3) - Civil support services

At Greenbushes, the world’s largest lithium mining operation, Melchor played a key role in delivering civil infrastructure for the Chemical Grade Plant 3 project. Initially engaged under a maintenance contract, Melchor successfully completed critical infrastructure works to support the site’s continued expansion, enhancing access, connectivity, and operational efficiency between the existing CGP2 infrastructure and the new CGP3 Wet and Dry Plants.

The scope of works included major earthworks, underground services, pavement construction, and reinforced concrete works. Key packages delivered by Melchor included the installation of underground services, supply and installation of precast concrete culverts, construction of NPI building slabs and drainage, batter stabilisation works, construction of the shipping road retaining wall, CGP3 Wet and Dry Plant roads, and the installation of modular office and ablution buildings.

As part of the road infrastructure package, Melchor completed bulk excavation and placement of engineered fill, subbase, and basecourse materials to construct durable access roads capable of supporting heavy mining operations. The works also included the application of 5,000 square metres of primeseal and the installation of 3,376 square metres of asphalt. To further enhance road performance and drainage, Melchor installed approximately 800 linear metres of kerbing, delivering a high-quality road network to support ongoing site operations.

Melchor also successfully delivered the batter stabilisation works and construction of the shipping road retaining wall. This scope included traffic management, settlement monitoring, site clearance, topsoil stripping and staged excavation of the embankment in accordance with geotechnical engineering requirements. The works culminated in the fabrication and installation of 60 metres of precast retaining wall segments, followed by backfilling and full reinstatement of the area.