Diagnosis of subsoil quality - Principle and uncertainties

Subsoil diagnostics have become an essential element in the development of legislation, either as a preventive measure in the context of impact studies for new developments, or as part of the regulatory upgrading of Installations Classées pour la Protection de l'Environnement (ICPE), or as part of safety measures when ICPEs are shut down, or, finally, as part of the reciprocal information provided to parties under various private law contracts (insurance, bank loans, mergers and acquisitions).

Given the technical and legal diversity of the situations faced by the parties involved, diagnosing the quality of the "subsoil" requires a highly rigorous approach that draws on a wide range of skills: metrology, geology, hydrogeology, pedology, geochemistry, biology, etc. The multiplicity of situations encountered means that a general methodology has to be established, which must be adapted specifically to each project.

The field of subsoil quality diagnostics covers a complex environment where mineral, gas and water phases coexist, in constant evolution under the effect of natural or anthropogenic factors. As a living environment, the subsoil is a reality where mineral and organic components, physical (porosity), hydraulic (permeability), biological (bacterial microflora) and geochemical (aerated or reducing environment) characteristics... largely control the behavior of foreign elements, which may be harmful to the environment and to man.

Please refer to [1] and [2] .