How We Discovered a Hidden Piece of History During Environmental Remediation in the Eastern Suburbs

What’s the most challenging part of an environmental remediation project?

The planning?

The compliance?

The unexpected discoveries?

The coordination with multiple stakeholders?

All of that.

Our recent Eastern Suburbs beachside remediation project shows the complexities and surprises that come with environmental remediation. Over the past few weeks, we’ve been sharing teasers about a mysterious discovery at this site. Now, we’re ready to reveal more details.

We were engaged to complete the remediation of a site under audit by the NSW EPA. The project involved the removal and validation of two hotspots—hydrocarbon and lead—alongside the possibility of an underground storage tank (UST).

A service locator was brought in to conduct ground-penetrating radar (GPR) scans. However, the tank’s proximity to a retaining wall caused too much interference, rendering the GPR images unclear.

During demolition, we uncovered significant asbestos debris in the fill soil near the assumed UST. Excavation revealed the UST was four times larger than any commercial tank we had encountered and was encased in brick—highly unusual.

Given the property’s history, once owned by a notorious Sydney underworld figure and frequented by the Prince of Wales during both world wars, we suspected we had found a bunker. We halted work and contacted an archaeologist, who eventually approved the UST removal.

Currently, we face a critical challenge: the tank is in loose sand mixed with asbestos debris. Removing the tank now would risk collapsing the pit, contaminating the natural sand with asbestos-laden fill. The site’s heritage status requires the developer to retain all sandstone blocks, which weigh between 50 kg to 1 tonne. The demolition contractor must delicately move these blocks to preserve them for reuse before we can remediate the asbestos-filled soil and finally remove the UST.

Here’s an interesting fact: this UST is linked to the first petrol pump installed in Australia, named a “Hammond” after the inventor, which became known as a “Bowser” in America.

Update: Successful Removal and Backfill

We’re excited to share that the tank has been successfully removed and validated. Due to safety concerns about slope collapse in the soft sand, the hole has been backfilled with clean natural sand.

This project showcases the complexities of environmental remediation and the importance of planning, historical consideration, and adaptive problem-solving.