A site contamination dispute requires examination not only of the substance present in a sample, but also the site's history, sampling conditions and distribution of changes. Where possible, data on conditions before the alleged event is preserved.
Subject of examination
- Soil and earth materials in the suspected impact zone
- Background areas and different depths
- Traces of spills, waste accumulation or material deliveries
Sample questions for the expert
- Which parameters confirm a change in soil condition?
- Are the boundaries of the surveyed zone and selection of background samples justified?
- Is there data linking the changes to the event examined?
- Is there sufficient data to select restoration measures?
The final questions are formulated according to the objects and circumstances of the particular task.
What to prepare
- A site plan and use history
- Documents concerning the accident, work or material placement
- Sampling records with coordinates and depths
- Laboratory test reports and previous surveys
How the examination is conducted
Sample representativeness, the methods used and the relevance of parameters to the task are assessed. Proposed explanations of contamination origin are compared with spatial, temporal and documentary information.
Scope and limitations
An exceedance does not automatically identify a particular responsible party. A description of an individual sample is not extended to the entire area without justification.
What the deliverable records
The opinion separates confirmed changes and causal links from hypotheses requiring additional sampling or analysis for verification.