Detailed Site Investigation

Summary

A Detailed Site Investigation (DSI) is an intrusive assessment that confirms the presence, extent, and severity of contamination through targeted sampling and laboratory analysis. It provides the technical evidence required to assess risk, satisfy regulators, and progress to remediation or site validation.

Definition

A Detailed Site Investigation (DSI) is a comprehensive, intrusive site assessment that builds on the findings of a Preliminary Site Investigation (PSI). It involves soil, groundwater, surface water, or air sampling to confirm the presence, type, extent, and concentration of contamination. The results are compared against environmental guidelines to assess potential risks to human health and the environment.

Why It Matters

A DSI provides the factual, scientific basis for remediation planning and regulatory approvals. Without a DSI, contamination risks may remain undefined, delaying projects or leading to non-compliance. For developers and landowners, a DSI is the critical bridge between identifying a potential issue and implementing a targeted, cost-effective remediation strategy.

When It’s Required

• Following a PSI: When contamination is suspected or confirmed.‍
• Regulatory Compliance: To meet environmental protection authority (EPA) requirements.‍
• Remediation Planning: Before designing a Remediation Action Plan (RAP)‍
• Site Closure: As part of validation for previously remediated land.

How We Can Help

Nova Group Pacific delivers regulator-aligned Detailed Site Investigations that provide defensible, decision-ready data for remediation planning and approvals.

Contaminated Land

Design and execution of DSIs to delineate contamination in soil, groundwater, surface water, or soil vapour, including development of conceptual site models and risk assessments.

Environmental Drilling

Intrusive investigation programs incorporating soil coring, groundwater sampling, vapour wells, and monitoring well installation to support accurate contamination characterisation.

Groundwater Sampling

Collection and analysis of groundwater samples to assess contaminant migration, plume extent, and potential impacts to receptors or offsite environments.

Environmental Monitoring

Targeted monitoring to assess contaminant behaviour, temporal variation, and compliance with environmental guideline values.

Environmental Approvals & Compliance

Preparation of DSI reporting suitable for EPA review, planning approvals, remediation approvals, and audit processes.

Contact us to discuss your project and receive expert guidance tailored to your environmental, planning, and compliance obligations.

Related Terms and Concepts

• Preliminary Site Investigation (PSI)‍
• Environmental Site Assessment (ESA)‍
• Contaminated Land‍
• Environmental Drilling‍
• Groundwater Sampling‍
• Remediation Action Plan (RAP)‍
• Site Remediation‍
• Site Validation Protocol