Preliminary Site Investigations in Sydney

Confluence Environmental provides Preliminary Site Investigations (PSI) and contaminated land assessments throughout Greater Sydney for Development Applications, rezoning, subdivision, redevelopment and property due diligence.

Sydney does not have one contamination history.

A former market garden in Blacktown presents a very different investigation problem to an industrial property in Alexandria, a former fuel site near Botany, or land containing historical asbestos fill in Parramatta.

The planning framework also varies between local government areas. While all Sydney councils operate within the broader NSW contaminated land framework, each Council may have its own Local Environmental Plan, Development Control Plan, contaminated land policy and information holdings.

For this reason, a Sydney PSI should consider both the history of the property and the specific planning requirements applying to its location.

If you have received a contamination-related request from Council, send us the property address, proposed development and any available Council correspondence and we can advise on an appropriate investigation scope.

Call 1300 855 447 or request a proposal from our contaminated land team.

For more information on the overall investigation process, see our Preliminary Site Investigation services across NSW.

Different Parts of Sydney Have Different Contamination Legacies

Greater Sydney has developed over former agricultural land, industrial precincts, reclaimed land, waste disposal areas, fuel infrastructure and some of the most intensively developed urban land in Australia.

Common historical issues can include:

• orchards and market gardens;

• industrial and manufacturing activities;

• imported and uncontrolled fill;

• asbestos-containing fill;

• former landfills and waste disposal areas;

• workshops and depots;

• service stations and underground fuel storage;

• chemical manufacturing;

• ports and bulk fuel storage; and

• contamination migrating from adjoining properties.

A good PSI needs to understand which of these issues are actually relevant to the individual property rather than applying the same generic assessment across the entire Sydney Basin.

Western Sydney – Orchards, Market Gardens and Historical Fill

Large parts of Western Sydney were historically used for orchards, market gardens, poultry farming and other agricultural activities before urban development.

Former agricultural land can require consideration of historical pesticide and chemical use, particularly where land is being converted to more sensitive uses such as residential development, childcare or education.

Historical fill is another recurring issue.

Land may have been raised or levelled decades ago without reliable information regarding the source of the material. Depending on its origin, fill may contain demolition debris, asbestos-containing materials, ash, metals or other contaminants.

The NSW EPA has also identified a number of legacy asbestos fill sites, primarily in Western Sydney, associated with historical disposal of James Hardie asbestos waste. Parramatta has been particularly affected by this legacy.

These issues illustrate why the present appearance of a property can provide very little information about what may exist beneath the ground.

Blacktown – Specific Contaminated Land Controls

Development across much of the Blacktown LGA is governed by the Blacktown Local Environmental Plan 2015 and Blacktown Development Control Plan 2015.

Importantly, the Blacktown DCP contains a dedicated Part I – Contaminated Land Guidelines.

Those guidelines establish procedures for considering contamination during:

• Planning Proposals;

• Development Applications; and

• Complying Development Certificates.

Blacktown Council's approach is precautionary and aims to identify contamination issues early in the planning process.

For development on former agricultural land, industrial properties or sites containing historical fill, this local framework can directly influence the information Council expects to receive.

Parramatta – Council Records and Legacy Asbestos Fill

The City of Parramatta operates under the Parramatta Local Environmental Plan 2023 and Parramatta Development Control Plan 2023.

Part 5 of the Parramatta DCP contains environmental management controls addressing contaminated land and requires potential contamination to be considered before a Development Application is submitted.

Council also maintains a Contaminated Land Policy and Procedure.

Parramatta Council notes that section 10.7 planning certificates may contain information relating to:

• previous contamination investigations;

• remediation notifications; and

• ongoing management requirements affecting land.

This is particularly relevant in an LGA containing a mixture of former industrial land, historical filling and known legacy asbestos-fill sites.

For a PSI in Parramatta, Council records can therefore be just as important as historical aerial photographs and current site observations.

Inner West – Industry, Workshops and Older Urban Land

The Inner West Local Environmental Plan 2022 provides the principal local planning framework for much of the Inner West.

Contaminated land is also specifically addressed through Council's DCP controls, including Section 2.11 – Contaminated Land, which is intended to ensure Council has sufficient evidence to determine whether contamination constrains a proposed development.

The Inner West has a long history of:

• manufacturing;

• mechanical workshops;

• rail-related activities;

• dry cleaning;

• fuel storage;

• warehouses;

• historical filling; and

• waste-generating commercial uses.

In these areas, the existing building may bear little relationship to activities that occurred on the property several decades earlier.

A PSI therefore needs to reconstruct the land-use history and determine which former activities create credible contamination risks.

City of Sydney – Contaminated Land Policy 2025

Development across most of the City of Sydney is governed by the Sydney Local Environmental Plan 2012 and Sydney Development Control Plan 2012.

The City also adopted an updated Contaminated Land Policy in 2025.

The policy establishes Council's approach to contaminated land in Development Applications and planning proposals and works alongside the NSW contaminated-land planning framework.

For properties in areas such as Alexandria, Waterloo, Rosebery and Zetland, historical industrial and commercial uses can be particularly relevant.

Potential issues may include:

• workshops and manufacturing;

• fuel storage;

• chemical use;

• dry cleaning;

• historical filling; and

• former industrial infrastructure.

A PSI in the City of Sydney should therefore consider both Council's current policy requirements and the often complex historical use of the site.

Botany, Alexandria and Sydney's Industrial South-East

The Botany area contains some of Sydney's most significant industrial contamination legacies.

Historical land uses have included:

• chemical manufacturing;

• bulk fuel and chemical storage;

• heavy industry;

• Port Botany operations; and

• extensive industrial development.

Contamination issues in the broader area have included chlorinated hydrocarbons, petroleum hydrocarbons, metals and contaminated groundwater within the Botany Sands Aquifer.

The EPA continues to oversee major legacy contamination associated with historical chemical manufacturing in Botany.

This is important for PSI work because a subject property may need to be assessed in the context of credible off-site groundwater or vapour migration, not just activities that occurred within its own boundary.

Canterbury-Bankstown – A Dedicated Contaminated Land Policy

The Canterbury-Bankstown LGA is governed by the Canterbury-Bankstown Local Environmental Plan 2023 and Canterbury-Bankstown Development Control Plan 2023.

Council also maintains a dedicated Contaminated Land Policy establishing how contamination is considered through its planning and environmental decision-making processes.

The LGA includes a mixture of:

• older industrial precincts;

• manufacturing and workshops;

• former market gardens;

• filling;

• fuel storage; and

• waste-related land uses.

For redevelopment projects, the applicable Council policy and the site's actual historical use need to be considered together when determining whether a PSI or more detailed investigation is appropriate.

Former Landfills and Waste Disposal

Historical waste disposal is another consideration across parts of Greater Sydney.

Former landfills, filled quarries and informal waste-disposal areas may present issues involving:

• contaminated fill;

• landfill gas;

• groundwater;

• buried waste; and

• settlement or geotechnical constraints.

The relevance of these issues depends strongly on the location and history of the individual property.

A nearby former landfill does not automatically mean a site is contaminated, but where a credible migration pathway or historical connection exists it may need to be considered within the Conceptual Site Model.

Fuel Storage and Former Service Stations

Former service stations, depots and underground petroleum storage systems occur throughout Greater Sydney.

Where historical fuel infrastructure is identified, a PSI may need to establish:

• where tanks and bowsers were located;

• whether underground pipework was present;

• whether tanks were removed;

• whether validation records exist;

• whether groundwater could have been affected; and

• whether surrounding properties could represent additional petroleum sources.

The absence of visible infrastructure today does not necessarily resolve these questions.

Why Council Matters When Scoping a Sydney PSI

All Sydney councils operate within the broader NSW contaminated-land planning framework, including Chapter 4 of State Environmental Planning Policy (Resilience and Hazards) 2021.

However, local requirements are not identical.

For example:

• City of Sydney – Sydney LEP 2012, Sydney DCP 2012 and Contaminated Land Policy 2025.

• City of Parramatta – Parramatta LEP 2023, Parramatta DCP 2023 and Contaminated Land Policy and Procedure.

• Blacktown City Council – Blacktown LEP 2015 and Blacktown DCP 2015, including Part I – Contaminated Land Guidelines.

• Canterbury-Bankstown Council – Canterbury-Bankstown LEP 2023, DCP 2023 and Contaminated Land Policy.

• Inner West Council – Inner West LEP 2022 and specific contaminated-land controls within the applicable DCP framework.

This matters because the scope required for a project may be influenced by:

• the relevant Council policy;

• information already held by Council;

• section 10.7 planning certificate information;

• the history of the property;

• the proposed change in land use; and

• previous contamination assessment or remediation.

At Confluence Environmental, we review the site and the planning context together rather than applying a generic Sydney PSI scope.

Why Engage Confluence Environmental for a Sydney PSI?

Local Planning Knowledge

We consider the relevant Council planning framework and contaminated-land requirements when developing the investigation scope.

Understanding of Sydney's Contamination Legacy

Our assessments consider the issues relevant to the particular part of Sydney, whether that involves former agricultural land, industrial activity, historical fill, petroleum infrastructure or off-site contamination.

Proportionate Investigation

A historical activity does not automatically mean a DSI is required.

We assess whether there is a credible source, pathway and receptor relationship and whether the remaining uncertainty actually matters to the proposed development.

Strong Technical Quality Assurance

Our contaminated-land reports undergo technical review appropriate to the complexity of the project, and we regularly involve CEnvP(SC) and CPSS CSAM practitioners in the review of our work.

Need a Preliminary Site Investigation in Sydney?

If you are preparing a Development Application, responding to Council, rezoning or subdividing land, or purchasing a property with a potentially contaminating history, send us:

• the site address;

• proposed development;

• Council correspondence;

• section 10.7 planning certificate where available; and

• previous environmental reports.

We can review the available information and provide a project-specific Preliminary Site Investigation scope.

Call Confluence Environmental on 1300 855 447 or request a proposal from our contaminated land team.

For more information about how the assessment process works, see our Preliminary Site Investigation services across NSW.