Environmental Drilling
Summary
Environmental drilling refers to intrusive drilling activities undertaken to investigate subsurface conditions for environmental assessment purposes. It is commonly used to collect soil, groundwater or vapour samples to support contaminated land investigations, risk assessment and remediation planning.
Environmental drilling is a key component of Preliminary Site Investigations (PSI), Detailed Site Investigations (DSI) and remediation validation programs, and must be carefully planned and supervised to ensure data quality and safety.
Definition
Environmental drilling is the use of drilling techniques to access subsurface soil and groundwater for sampling, testing and monitoring as part of environmental investigations. Methods may include borehole drilling, test pits, direct push techniques or installation of monitoring wells, depending on site conditions and investigation objectives.
Drilling works are typically undertaken in accordance with a sampling and analysis plan and relevant safety and environmental controls.
Why Environmental Drilling Matters
From an investigation perspective, environmental drilling provides the primary means of understanding subsurface conditions and identifying contamination that cannot be assessed through surface inspection alone.
Poorly planned or executed drilling can compromise sample integrity, result in cross-contamination or produce data that is not suitable for regulatory or planning decisions. Appropriate drilling methods, sample handling and documentation are essential to ensure results are representative and defensible.
Environmental drilling also carries health, safety and environmental risks, particularly on contaminated sites. Management of drilling spoils, groundwater, vapours and potential asbestos or hazardous materials must be considered as part of the drilling program.
When Environmental Drilling Is Typically Required
Environmental drilling is commonly required where:
Subsurface contamination is suspected or identified
Soil or groundwater sampling is required to support a PSI or DSI
Monitoring wells are needed to assess groundwater conditions
Vapour intrusion or gas risks require investigation
Validation sampling is required following remediation
Regulatory authorities require intrusive investigation to support approvals
The scope of drilling is typically tailored to site-specific risks and investigation objectives.
Common Environmental Drilling Activities
Environmental drilling programs may include:
Borehole drilling for soil sampling
Installation of groundwater monitoring wells
Collection of soil vapour or gas samples
Test pitting for shallow soil assessment
Sampling for waste classification or validation purposes
Drilling activities are often staged to refine understanding as investigations progress.
Legislative and Regulatory Context
Environmental drilling is undertaken within the framework of work health and safety legislation, environmental protection requirements and industry guidance.
In New South Wales, drilling activities associated with contaminated land investigations are typically assessed by regulators and councils as part of the development and remediation approval process. Regulators expect drilling programs to be appropriately scoped, documented and supervised.
How We Can Help
Confluence Environmental designs and oversees environmental drilling programs as part of contaminated land and groundwater investigations.
Our services typically include:
Development of drilling and sampling programs
Supervision of drilling contractors
Collection and handling of environmental samples
Management of drilling spoils and investigation-derived waste
Interpretation of results and reporting for regulatory review
We focus on ensuring drilling programs are safe, efficient and produce data suitable for decision-making.
Related Terms and Concepts
Preliminary Site Investigation
Detailed Site Investigation
Groundwater Investigation
Sampling and Analysis Plan
Chain of Custody
Contaminated Land
Site Validation