6. Mistakes to avoid

6.1 Don't neglect hydrogeological expertise

This expertise is essential for :

• understand the migratory phenomena that play a decisive role in risk assessment ;

• design the right groundwater sampling tools to identify NAPL or DNAPL and avoid artificial communication between aquifers.

So it's important to document and interpret correctly:

• soil and subsoil data: soil and lithological nature, local and regional geological context... ;

• groundwater data: spatial extent, hydrogeological characteristics of aquifers, river-groundwater or surface-water-groundwater relationships, presence of natural...