When a Preliminary Site Investigation (PSI) identifies potential contamination, the next step is often a Detailed Site Investigation (DSI).
At Integrated Environmental Pty Ltd, we conduct DSIs to provide property owners, developers, and councils with a clear understanding of the nature, extent, and risks of contamination on a site. These investigations are crucial for planning, development approvals, and protecting human health and the environment.
What Is a Detailed Site Investigation?
A Detailed Site Investigation (DSI) is a comprehensive environmental assessment that goes beyond desktop research and visual inspection. It involves soil, groundwater, vapour, and surface water sampling to confirm whether contaminants are present, in what concentrations, and how far they may have migrated.
The results determine whether remediation is required and guide the development of a Remediation Action Plan (RAP) if needed.
Why DSIs Are Required
Councils, regulators, or certifiers may require a DSI if:
- A PSI indicates potential or actual contamination.
- The site has a history of industrial, commercial, or agricultural use (e.g. service stations, dry cleaners, workshops).
- There are visible signs of contamination (e.g. staining, fill material, asbestos fragments).
- The land is being redeveloped into a more sensitive use (e.g. childcare centres, schools, residential housing).
Failing to complete a DSI when required can result in DA delays, compliance breaches, or financial risk.
What Does a DSI Involve?
When Integrated Environmental undertakes a DSI, the process includes:
- Sampling Design
- Developing a sampling plan based on PSI findings.
- Determining the number, type, and location of samples required.
- Fieldwork & Sampling
- Collection of soil, groundwater, and vapour samples.
- Use of drilling rigs, monitoring wells, and field-testing equipment.
- Laboratory Analysis
- Testing for hydrocarbons, heavy metals, asbestos, PFAS, and other contaminants.
- Using NATA-accredited laboratories for reliable results.
- Data Interpretation
- Comparing results to NEPM (2013) Health Investigation Levels and relevant guidelines.
- Identifying risks to human health and the environment.
- Reporting
- Delivering a comprehensive DSI report, including contamination maps, conceptual site models, and clear recommendations.
The Benefits of a DSI
- Provides certainty for developers and property owners.
- Satisfies council, EPA, and planning authority requirements.
- Identifies contamination before costly construction delays.
- Supports informed decisions about remediation and redevelopment.
- Protects public health and the environment.
How We Help
At Integrated Environmental, we specialise in fast, compliant, and cost-effective DSIs. Our team has experience with residential, commercial, and large infrastructure projects across NSW. We mobilise quickly, manage the entire process, and provide clear, council-ready reporting.
Need a Detailed Site Investigation?
If your PSI has identified potential contamination — or if council has requested a DSI as part of your DA process — we can help.
Integrated Environmental Pty Ltd provides Detailed Site Investigations, Remediation Action Plans, and validation reporting across NSW.
Contact us today to ensure your site assessment is completed on time and in full compliance.