Preliminary Site Investigation – Abbotsford Residential Development

Project overview

A residential development was proposed for a parcel in Abbotsford, Victoria adjacent to properties subject to an Environmental Audit Overlay (EAO). The local planning authority required a Preliminary Site Investigation (PSI) to inform whether past land uses could present contamination risks and whether an environmental audit or remediation would be necessary before construction and occupation for a sensitive use.

What is a Preliminary Site Investigation (PSI)?

A PSI is a predominantly desk-based assessment that reviews site history, planning records, previous environmental reports, aerial imagery, available groundwater and bore data, and geological/hydrogeological context to identify potential contaminants of concern. The outcome is a practicable recommendation on whether intrusive investigation (soil/groundwater sampling) or an environmental audit is warranted.

What an Environmental Audit Overlay (EAO) means

An EAO on or near land signals that contamination is known or reasonably suspected and that an environmental audit may be required before redevelopment for sensitive uses such as residences or childcare. A PSI is commonly used by planning authorities to decide whether an audit is necessary or whether a site can proceed without further intrusive work.

iEnvi assessment summary

• Location: Abbotsford, Victoria.
• Scope: Desk-based PSI reviewing historic land use, planning records, previous reports, aerial photography, and available groundwater and geological information.
• Nearby potential sources considered: former boot factory and an electrical substation adjoining/near the site (no direct source identified on the property).
• Key outcome: No indicators of on‑site contamination or migrating contamination from adjacent parcels were identified in the available records; intrusive soil sampling was therefore not recommended.
• Turnaround: PSI completed and delivered within seven business days to meet planning permit requirements.

Findings and practical implications

The PSI concluded the site presented a low risk of contamination for the proposed residential development. As a result:

• A full EPA environmental audit was not required to satisfy the planning authority for the current proposal.
• The planning application could progress without delay due to contaminated-land conditions, yielding time and cost savings for the client.
• No immediate remediation or intrusive investigation was recommended; however, standard construction-phase controls and due diligence (e.g. management of any unexpected finds) remain good practice.

Practical takeaways for developers and project teams

1. Early desk-based PSI can rapidly clarify whether intrusive investigation or audit will be needed — saving time and avoiding unnecessary costs if the risk is low.
2. Where an EAO applies nearby, planning authorities commonly use PSI outcomes to decide whether an audit is required; a clear, well-documented PSI reduces uncertainty in the approvals pathway.
3. Even when intrusive sampling is not required, include contingency in programs and budgets for unexpected contamination finds during excavation or service works.

Next steps and recommended risk controls

• Proceed with planning lodgement using the PSI report to satisfy the planning condition requiring preliminary contamination assessment.
• Adopt standard unexpected-finds procedures in the construction management plan and ensure workers are briefed on reporting and handling suspected contaminated material.
• If future designs propose deeper excavation, basements or change to a more sensitive land use, consider re‑assessing the need for intrusive investigation.

Conclusion

The iEnvi PSI provided a rapid, evidence-based determination that the Abbotsford site is low risk for contamination in the context of the proposed residential development. This outcome reduced regulatory uncertainty, avoided the time and cost of a full environmental audit, and enabled the planning application to move forward with appropriate construction-phase controls in place.

To discuss a tailored contamination assessment for your development or to request a fast-turnaround PSI, contact our specialist team on 13000 43684 or visit /contact/.