The assessment criteria presented here are intended as an aid in classifying the health and environmental hazards associated with contaminated sites by means of the MIFO method. “Contaminated sites” refers to any waste tip, land, groundwater or sediment showing concentrations of pollutants that are significantly elevated above background levels due to local emissions.
The MIFO method is a tool for inventorying contaminated sites and assigning them to hazard classes. Health and environmental hazards at a contaminated site are determined by the hazardousness of the pollutants (depending on their chemical and physical properties), the pollutant levels (concentrations), their migration potential (depending on the nature of the soil and on groundwater movements), the sensitivity of the site (risk of human exposure) and its ecological value (natural conservation values in the neighbourhood). These factors are each classified on a four-point scale.
The four-point scale for deviation of pollutant levels from reference values (indicating the extent to which the site has been affected by local pollution sources) can be related to the five-point scales used in other environmental quality assessment criteria: essentially it is a subdivision or extension of Deviation Class 5 as defined by those criteria.
The final health and environmental hazard classification is based on a balanced appraisal of the above factors. A special diagram is used to give a clearer overview of the information.
The printed version of these assessment criteria contains detailed guidelines for the appraisal of risk factors as well as forms to systematise and simplify risk assessments.
Individual assessment criteria have been established for:
- hazardousness of pollutants
- pollutant levels
- migration potential
- sensitivity and ecological ("protective") value
Methods for inventories of contaminated sites
Introduction to a method for inventories and risk classification of contaminated sites