Detailed Site Investigation (DSI)
Define the contamination before planning the next move
Turn suspected contamination into clear evidence
A preliminary assessment may indicate contamination, but it cannot always show its concentration, movement or full extent. Proceeding without that detail can expose a project to approval delays, unexpected remediation costs and risks to people or surrounding properties.
Geotesta completes targeted drilling, sampling and analysis across soil, groundwater, surface water and soil vapour where relevant. The findings refine the conceptual site model and establish whether the issue requires remediation, monitoring, further investigation or no additional action.
Investigation Methods
Targeted drilling
Boreholes are positioned around identified or suspected sources to collect samples from the depths that matter to the investigation.
Soil sampling
Representative soil samples are collected, logged and submitted for analysis to determine contaminant type, concentration and distribution.
Groundwater assessment
Where groundwater may be affected, monitoring wells and sampling can help determine whether contamination has migrated beyond its original source.
Surface water
Surface water may be sampled where runoff, discharge or nearby waterways create a possible contamination pathway.
Soil vapour
Vapour assessment may be required where volatile contaminants could move through soil and create a risk to existing or proposed buildings.
Laboratory analysis
Samples are analysed for the contaminants relevant to the site history, preliminary findings and proposed land use.
Practical environmental advice grounded in evidence
Frequently Asked Questions
A DSI is a targeted environmental investigation that uses field sampling and laboratory analysis to determine the type, concentration and extent of contamination.
Yes. Detailed Site Investigation, Phase 2 environmental assessment and environmental site assessment are commonly used for the same detailed contamination investigation stage.
A Detailed Site Investigation may be required when a Preliminary Site Investigation identifies a potential contamination risk, or when further investigation is needed to meet planning, regulatory, remediation or environmental audit requirements.
Yes. Where site history, regulatory information or known contamination already indicates a significant issue, detailed investigation may begin without completing a separate PSI first.
Depending on the site, a DSI may assess soil, groundwater, surface water and soil vapour, either individually or as connected contamination pathways.
Sampling locations and depths are based on the site history, preliminary findings, suspected sources, likely migration pathways and the people or environments that could be affected.