Brownfield sites are found across Western Australia, particularly in areas with industrial, commercial or agricultural histories. Understanding the common contaminants present on these sites is crucial for redevelopment, as it forms the foundation of effective assessment and remediation. e Contaminated Sites Act 2003.
At West Soil & Water, we offer brownfield consultations as a part of our contaminated land management services. Our consultant have an expertise in remediation and create all strategies in line with the Contaminated Sites Act 2003.
This article outlines common contaminants found on brownfields and how we approach their treatment. If you would like more information or would prefer to speak directly with a member of our team, you can contact us at sam@westsoilandwater.com.au or call 0424 021 264.
Brownfields are parcels of land that were previously developed and used for industrial, commercial or agricultural purposes. Today, they sit vacant, underutilised or are undergoing redevelopment.
In many cases, these sites are affected by real or suspected contamination caused by historical activities. In Western Australia, these activities include:
Fuel storage and handling
Industrial processes involving chemicals, solvents or heavy metals
Poor waste disposal practices
Pesticide or fertiliser use
While not all brownfield sites are contaminated, any proposed redevelopment raises environmental concerns that require investigation. Identifying contamination early helps manage risk and supports safe, responsible redevelopment.
There are many substances that could be discovered as a contaminant on a brownfield site. The nature of the specific site, including its location and past uses, will determine exactly what contaminants are found there. This could include:
Petroleum Hydrocarbons: Including diesel, petrol and lubricants, these are commonly found on former service stations, fuel depots and transport yards.
Heavy Metals: Sites with industrial or agricultural histories can contain lead, arsenic and other metals
Asbestos: Frequently present in demolition rubble, old fill materials or soils on sites with historical building activities or waste dumping.
Polycyclic Aromatic Hydrocarbons (PAHs): Found on sites associated with gasworks, asphalt production or wood treatment, PAHs are by-products of incomplete combustion.
Chlorinated Solvents: Used in dry cleaning, degreasing and chemical manufacturing, these solvents can persist in groundwater and pose significant remediation challenges.
Pesticides and Herbicides: Agricultural sites may have residual pesticides and herbicides in the soil.
Per- and Polyfluoroalkyl Substances (PFAS): These synthetic chemicals are used in firefighting foams and industrial applications and have been detected on sites like airports and defence facilities.
These contaminants are best identified by conducting Phase I and Phase II Environmental Site Assessments (ESAs). The information gathered in these assessments can the be used to inform the development of appropriate remediation strategies.
Once contamination is identified on a brownfield site it must undergo remediation to make it safe for future use. An experienced environmental consultant can help you develop a targeted action plan based on the type of contaminant, the extent of its spread, and the intended use of the site.
In Western Australia, common remediation methods include:
Excavation and Offsite Disposal – The removal of contaminated soil and other hazardous waste to be transported to licensed facilities. This is often used for asbestos or heavily impacted soil.
In-Situ Treatment – Techniques like bioremediation or chemical oxidation are applied directly to the soil or groundwater to break down hydrocarbons, solvents or other pollutants.
Containment and Capping – For sites with low-risk or difficult-to-remove contamination, engineered barriers or clean fill layers can prevent exposure.
Groundwater Management – Pump-and-treat systems or reactive barriers may be used to intercept and treat contaminated groundwater.
Monitored Natural Attenuation – In some cases, natural processes are allowed to reduce contamination levels over time. Normally, they must be paired with strict monitoring.
Regardless of the method you choose, your Remediation Action Plan (RAPs) must comply with WA’s Contaminated Sites Act 2003 and be supported by appropriate site assessments and planning. At West Soil & Water, we tailor each strategy to the site’s risks, constraints and long-term redevelopment goals, ensuring that they meet these standards.
With a firm understanding of the contaminants commonly present on Western Australian brownfield sites, developers and environmental professionals can create effective remediation plans. This will ensure that projects are safe, sustainable and compliant with environmental standards.
At West Soil & Water, our team use their near 15 years of experience to create targeted RAPs that employ proven methods. If you would like to speak with a member of our team, you can contact us at sam@westsoilandwater.com.au or call 0424 021 264.