Hazardous Materials Survey, Register and Preliminary Site Investigation – Former Abattoir Site (Central Coast NSW)
Prepared by Confluence Environmental — environmental, contaminated land and hazardous materials consultants supporting development approvals, remediation planning and validation across NSW.
Confluence Environmental was engaged during the early planning phase of a proposed site decommissioning and flood mitigation project to undertake a comprehensive hazardous materials survey and register alongside a detailed Preliminary Site Investigation (PSI).
The site comprised a 2-hectare former abattoir facility, constructed in the 1960s, consisting of multiple buildings arranged over two levels. The engagement was initiated to support the safe decommissioning of historical infrastructure, the importation of Virgin Excavated Natural Material (VENM) for flood mitigation works, and the preparation of a robust contaminated land assessment to accompany a Development Application (DA) lodged with Central Coast Council.
Project Background
The former abattoir had been subject to a range of historical and more recent activities that presented a complex environmental risk profile. In addition to legacy industrial use associated with meat processing operations, the site had also been used for subsequent activities including boat fabrication and uncontrolled storage of hazardous chemicals.
Given the age of construction and nature of operations, the site presented a high likelihood of hazardous building materials and potential subsurface contamination requiring careful investigation and documentation prior to any disturbance or redevelopment.
Scope of Services
Confluence Environmental delivered an integrated program of hazardous materials assessment and contaminated land investigation to support planning and regulatory decision-making.
The scope of work included:
Intrusive and non-intrusive hazardous materials surveys across all accessible buildings
Identification and assessment of asbestos-containing materials, including friable materials
Assessment of lead-containing paints, synthetic mineral fibres (SMF) and other hazardous materials
Preparation of a site-specific hazardous materials register
Completion of a comprehensive Preliminary Site Investigation
Development of a detailed conceptual site model (CSM)
Reporting to support DA lodgement and engagement with Central Coast Council
Hazardous Materials Findings
The hazardous materials assessment identified a range of high-risk legacy materials consistent with the age and industrial history of the site, including:
Friable asbestos pipe lagging within service corridors and plant areas
Heavily deteriorated lead-containing paints applied to structural steel and internal surfaces
Synthetic mineral fibre insulation within plant rooms and ceiling spaces
Additional hazardous materials associated with historical industrial infrastructure
Given the public and worker safety implications, findings were clearly documented with material condition, accessibility and disturbance risk assessed to support staged decommissioning and removal planning.
Contaminated Land Assessment and PSI Outcomes
The Preliminary Site Investigation identified several key subsurface and land-use related considerations relevant to the proposed works:
A suspected underground petroleum storage system (UPSS) associated with historical operations
Presence of imported fill material of unknown origin and quality
Evidence of potentially contaminating activities linked to boat fabrication and chemical storage
Areas requiring further consideration prior to bulk earthworks or fill importation
The PSI was deliberately structured to distinguish confirmed risks from uncertainties, allowing Council to clearly understand where additional controls or staging may be required without unnecessarily escalating investigation scope.
Conceptual Site Model and Planning Integration
A highly detailed conceptual site model (CSM) was developed to clearly articulate contaminant sources, exposure pathways and sensitive receptors relevant to the proposed land use and flood mitigation works.
The CSM played a central role in:
Framing contamination risk in a planning context
Supporting the proposed importation of VENM
Demonstrating how risks would be managed during decommissioning
Providing transparency for Central Coast Council assessment
By aligning the CSM directly with the DA documentation, the assessment supported a clear and defensible planning pathway.
Key Challenges
The project presented several technical and planning challenges, including:
Presence of friable asbestos requiring careful documentation and future control
Multiple historical and recent contaminating activities
Flood-affected land requiring fill placement and level modification
Balancing regulatory rigour with proportionate investigation
Clear communication and structured reporting were critical to ensuring that identified risks were appropriately contextualised rather than overstated.
Outcomes
The project delivered a robust, planning-ready package of documentation, including a compliant hazardous materials register and a comprehensive PSI tailored specifically to DA requirements.
The assessment provided Central Coast Council with confidence that contamination risks had been appropriately identified, assessed and managed within the planning framework, allowing the project to progress toward decommissioning and flood mitigation works without unnecessary delay.
Why This Project Matters
Complex legacy industrial sites require more than checklist-driven investigations. This project demonstrates the importance of:
Integrating hazardous materials assessment with contaminated land investigation
Developing a defensible conceptual site model
Aligning environmental reporting directly with planning objectives
Providing proportionate, regulator-ready documentation
Confluence Environmental’s Role
Confluence Environmental provides independent hazardous materials surveys, contaminated land assessments and planning support for complex redevelopment sites across NSW.
Our focus is on clear risk identification, practical management pathways and documentation that supports confident regulatory and planning decisions.