From brownfield site to commercial build-ready

The brief

A 16.8 hectare parcel of land was originally purchased by a petrochemical company decades ago to provide a buffer zone between its refinery in Altona and residential areas in Williamstown. As refinery production contracted (eventually ceasing in 2020), the buffer zone land was no longer required and sold to a developer in 2017.

To provide much needed space for new commercial projects, the brownfield site needed to be prepared for future development. While the soil was not contaminated by petrochemicals by its former owner, it did contain inert waste in addition to some friable and non-friable asbestos.

Industrial Environmental was engaged to perform soil remediation services to the strict standards required by the former owner and to construct the underground civil infrastructure and service corridors to support proposed land sub-divisions.

Execution

First step was to engage an Environmental Auditor, Environmental Consultant and Occupational Hygienist to develop a detailed Environmental Site Assessment and Remediation Action plan. 

Following a cost and environmental analysis of remediation options, the auditor and consultant recommended compacting the site and sealing it beneath a capping. This remediation solution also took into consideration the proximity of residential properties across the railway in addition to other industrial and commercial sites along another boundary of the site. Compacting, protecting and capping posed less risk to the community.

The developer provided designs for the subdivision, which included roads, driveways and services such as stormwater, sewer and electricity. Industrial Environmental dug out all the channels and underground paths required to hold future underground service infrastructure. As always, we over dug the required depth by an additional 500mm in both depth and width to reduce the possibility of future trades reaching the soil left insitu.

All soil we extracted was treated to ensure any friable and non-friable asbestos materials in addition to rubbish were removed and safely transported offsite for disposal. The soil was then replaced to low-lying areas of the site. The site surface was compacted to smooth any debris or loose materials and to allow proper adhesion of the marker layer.

A marker layer was applied evenly over the impacted soil. This provided a barrier to prevent access to contaminants and helps identify layers in the soil which should be avoided in future. Approximately 800mm of clean clay was laid down as a top dressing over the marker layer to improve the site’s usability.

Throughout the project, Industrial Environmental ensured dust and soil handling was managed with precision to mitigate any risk to the community and local buildings. Our aim was to ensure we did not add to the developer’s interactions with both WorkSafe and the community.

Outcome

The remediation project was delivered by Industrial Environmental on time and budget. The client proceeded with subdividing the property into 88 lots which have now all been sold. The site has since been redeveloped to accommodate a range of commercial properties including major convenience retailers and restaurants.