Zoe Smith: Navigating the complex world of contaminated land and PFAS

Zoe Smith’s journey into the world of contaminated land may seem unconventional, yet it reflects a long-standing passion for public health and environmental stewardship.

“I was formerly a registered nurse, but I have always had a passionate interest in public health and the environment,” she tells. “Working in the contaminated land industry seemed like the right fit.”

With years of experience tackling complex remediation projects, she has become a trusted voice on one of the most challenging environmental issues facing Australia today: PFAS contamination.

The thrill and complexity of contaminated land work

Smith, who is Senior Associate Environmental Scientist at Senversa, describes the diversity of her work as a major draw.

“What I find most interesting about the contaminated land industry is the diversity of projects and the opportunity to work with great clients and collaborative teams,” she shares.

"I especially enjoy being part of large development projects where contamination is addressed as part of revitalising urban areas. Watching a city evolve and improve because of the work we do is rewarding.”

However, she is candid about the challenges. Regulatory lag, particularly in response to emerging contaminants like PFAS, can slow remediation efforts.

“One of the biggest challenges I see in the contaminated land industry is the slow response from government bodies in keeping up with emerging science,” Smith confirms.

“Finding sustainable, science-backed solutions that genuinely improve environmental outcomes is complex but essential.”

Understanding PFAS: Why they’re different

PFAS (per- and polyfluoroalkyl substances) are notoriously persistent chemicals, used historically in firefighting foams, industrial processes and chemical handling.

Their unique chemical structure strong carbon-fluorine bonds – makes them extremely resistant to degradation, earning them the nickname “forever chemicals.”

“PFAS are among the most challenging contaminants in environmental science due to their persistence, mobility, and complex behaviour in soil, water, and biota,” explains Smith.

“Unlike many other contaminants that degrade over time or bind tightly to soil, PFAS can remain active and bioavailable for decades. This complicates both containment and remediation efforts.”

The difficulties extend beyond chemistry. With thousands of PFAS compounds identified, only a handful are routinely monitored – primarily PFOS, PFOA and PFHxS.

Analytical methods for complex matrices like sediments, biosolids and biological tissues are limited, requiring advanced techniques such as TOP Assay and time-of-flight mass spectrometry.

Meanwhile, regulations struggle to keep pace with emerging evidence.

“Australia’s PFAS National Environmental Management Plan (NEMP) Version 3.0 (2025) is a major step forward,” says Smith, “but much of the focus remains on containment rather than elimination. There’s still a gap between what science tells us and what regulatory frameworks require.”

Complex histories, complex pathways

A major challenge with PFAS is the legacy nature of contamination. Many sites have long, layered histories – Industrial operations, chemical storage, fire training and even fuel handling –making it difficult to trace contamination pathways or pinpoint origins.

“Some sites show PFAS residues in subsurface concrete structures, oily water runoff systems, and drainage networks,” Smith says.

“These have accumulated over decades of maintenance activities, creating a web of potential environmental concerns. Yet direct evidence of release pathways can be limited, complicating liability assessments.”

Even where contamination is known, migration patterns are difficult to predict. PFAS can leach from near-surface soils, travel through groundwater, or move via surface water runoff.

Seasonal variability, groundwater flow dynamics, and bioaccumulation in ecosystems all contribute to uncertainty. “Groundwater monitoring often shows gradual increases in PFAS concentrations linked to seasonal rainfall and surface water flux rather than recent contamination events,” Smith says.

This uncertainty has significant implications for businesses. Regulatory expectations now require companies to proactively manage PFAS risks, even if contamination originates from historical activities.

Landowners, developers and occupiers face increasing pressure to demonstrate due diligence, document site histories, and mitigate risks before undertaking development.

Sector impacts: From councils to construction

PFAS contamination is not a niche problem – it touches multiple sectors, each with unique challenges. Local councils, for instance, are often at the frontline, balancing redevelopment ambitions, community expectations and regulatory compliance.

“Councils are increasingly involved in PFAS management due to legacy contamination and redevelopment pressures,” Smith agrees. “They must carefully navigate community concerns while ensuring that public spaces are safe and compliant.”

Airports are heavily affected, largely due to historical use of PFAS-containing firefighting foams. Contamination plumes at these sites are often extensive, requiring complex investigations and remediation strategies.

Industrial sites present their own difficulties, with PFAS arising from manufacturing processes, chemical handling and fire safety infrastructure.

Construction projects, meanwhile, face regulatory restrictions on soil reuse, rising disposal costs, and potential redesigns to accommodate PFAS mitigation measures.

Smith also points out that PFAS contamination can delay projects, increase costs and complicate waste management.

“Circular economy initiatives, while environmentally motivated, can inadvertently reintroduce contamination into materials, creating liability challenges for developers and contractors,” she says.

Liability, insurance and risk management

PFAS presents a particularly thorny challenge in terms of liability. Many sites were contaminated decades ago, often with incomplete records.

Current landowners may be held responsible, even if they had no role in the original contamination. Insurers are grappling with how to cover claims in a landscape of evolving regulations and complex chemical behaviour.

Policies often include exclusions for known contaminants, making PFAS-related coverage a grey area. “Historical ambiguity complicates source attribution,” Smith explains.

“Incomplete records, overlapping land uses, and diffuse contamination make it difficult to definitively trace PFAS origins. This can affect both liability and insurance coverage.”

She suggests businesses adopt proactive, transparent communication with insurers.

“Disclose any PFAS-related findings early, even if contamination is only suspected, and provide clear documentation such as site histories, conceptual site models, and environmental audits. Framing the issue in terms of risk rather than just presence helps insurers better understand the context.”

Effective risk mitigation

Despite the challenges, Smith emphasises that science-based mitigation strategies can make a real difference. “The most effective measures combine source control, containment and adaptive reuse strategies.

"Stormwater and surface water controls, rapid site investigations and human health and ecological risk assessments help prioritise hotspots and inform targeted remediation,” she says.

Community engagement is another critical element. PFAS investigations often trigger public anxiety, even when contamination levels are low. Clear, transparent communication helps manage reputational risk and supports smoother remediation projects.

Training for contractors and stakeholders ensures that mitigation strategies are consistently applied. Businesses can also enhance defensibility by thoroughly reviewing historical site activities, documenting contamination pathways, and developing robust conceptual site models.

“Risk assessments should follow national guidelines and include toxicity and exposure evaluations for both human and ecological receptors,” Smith advises.

“Engage proactively with regulators, insurers and community stakeholders to ensure all parties understand the risk context and remediation strategy.”

Call for evidence-based policy

The PFAS challenge is far from over. Australia’s regulatory landscape is evolving, but scientific uncertainty and historical legacies mean that risk management will remain complex.

“Addressing legacy contamination while navigating scientific uncertainty and evolving regulatory expectations is critical for protecting communities, businesses, and the environment,” Smith says.

At the upcoming 2025 ANZIIF Australia Liability Conference, Smith will share her insights, including highlighting the importance of evidence-based strategies, proactive stakeholder engagement and flexible remediation planning.

Her advice for industry professionals is clear: anticipate complexity, document rigorously, communicate transparently and adopt mitigation measures grounded in science.

For Smith, the motivation behind the technical and regulatory work is deeply human. “It’s incredibly satisfying to see land transformed and communities benefit from remediation,” she says. “For me, that is the heart of this industry creating healthier, safer and more sustainable environments for everyone.”

Learn from Zoe Smith at the 2025 ANZIIF Australia Liability Conference. Book now.