Letourneur Conseil > IEM

Environmental Condition Interpretation (ECI)

Environmental Status Interpretation (ESI) is a management tool for polluted sites and soils. This tool can only be used if the use of the study site is fixed and known. The aim is to determine the compatibility of the state of the environment (soil, groundwater, surface water, ambient air, etc.) with current uses from a health point of view. These uses concern human populations, but may also involve the natural resources to be protected.

The IEM approach is as follows.


Step 1 of the IEM process: identifying usage patterns - site visit

  • Who are the users? Adults or children, permanent or temporary users;
  • What type of use? Housing, schools, recreational facilities;
  • What are users' habits? Consumption habits, time spent on the premises.

Stage 2 of the IEM: bibliographical research - historical and vulnerability study

In addition to identifying uses, it is necessary to carry out bibliographical research in order to define which environments are likely to contain pollution. This research is carried out in several ways:

  • Consultation of online databases;
  • Consultation of documents in prefectures, departmental archives, town halls or on the premises of competent authorities (ARS, DRIEE, DREAL, DDT).

Step 3 of the IEM: Diagnosis of mediaselected


This stage is carried out following the results obtained in the first two stages. An investigation program is drawn up for each of the selected environments likely to contain pollution. These investigations can only be carried out with the agreement of the various parties involved (owners, tenants, operators, managers). If it is impossible to carry out investigations in certain areas (refusal of occupants, inaccessibility), models can be used, integrating data obtained from neighboring areas.

IEM step 4: results management

In order to draw conclusions, the results can be compared with several databases;

  • Current management values (surface water, groundwater, foodstuffs, indoor and outdoor air);
  • Initial site status values;
  • Values of the local reference environment;
  • Situation analysis values (soil, soil gas, indoor air and outdoor air);
  • Quality data on various exposure media.

If no database is available for comparison, a quantitative health risk assessment will be carried out using the IEM grid provided by the French Ministry for the Environment. In order to use this grid effectively, a number of input data are required. These correspond to the findings of steps 1, 2 and 3 of the IEM.

IEM step 5: conclusion, actions to be taken

Interpretation of the results obtained by comparing values and/or using the IEM grid makes it possible to determine whether or not the environment is compatible with existing uses. The study site is then categorized with specific actions to be taken:

  • In the event of health compatibility and with pollution sources under control:
    • Maintain fixed uses by keeping a record of them (easements, restrictions on use, etc.);
    • Set up a monitoring network to ensure the sustainability of the situation (only feasible for certain environments);
  • In the event of health compatibility but with uncontrolled sources of pollution:
    • Implement a management plan;
  • In case of sanitary incompatibility :
    • Implement simple management actions to restore compatibility (remove source of pollution, cover impacted area);
    • Implement a management plan.

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