EPA On-line Tools for Site Assessment Calculation
Background
The information which follows provides some background on the site, and identifies the primary and secondary directives
which guided the course of the investigation. Questions are posed throughout the example to encourage you to think
about the basic concepts of groundwater flow and contaminant transport, and how they can be applied to improve
investigative techniques.
A useful approach during the field investigation phase is to first
develop a conceptual model or working hypothesis, which can then be tested through fieldwork, and modified
as the investigation proceeds.
A conceptual model can be a written description, or represented graphically as a flow chart or schematic figure.
It is used to "visualize" site conditions, identify data gaps, define contaminant migration and identify potential receptors.
Think about the idea of a conceptual model as you go through the example, and about how you would apply the technique
to a project of your own.
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