The VOLASOIL risk assessment model based on CSOIL for soils contaminated with volatile compounds

The CSOIL exposure model was developed for derivation of ntervention Values for soil and groundwater clean-up. These Intervention Values are based on potential risks to humans exposed to soil contaminants. Theoretical evaluation of the CSOIL's volatilization module has shown to be not suitable for actual risk-assessment. For this reason, the VOLASOIL model has been developed for actual risk assessment in case of volatile soil contaminants. The VOLASOIL model calculates the indoor air concentration for the Dutch situation in buildings situated on soils contaminated with volatile compounds. The VOLASOIL model can be seen as an optimum between scientifically sound and applicable in practice. The model can be used for site-specific risk assessment because of the possibility of flexible combination of modelling and measurements and calculations being made for several specific contamination cases. Some of these are floating contaminant layers, pure contaminant in the open capillary zone, contaminated groundwater in crawl spaces, et cetera. The VOLASOIL model could be used as a decision-support tool within the framework of soil clean-up priority (Soil Protection Act), construction permit issues (Housing Act), and soil quality management (spatial planning). A user-friendly Windows-application has been developed for using the VOLASOIL model in practice. This computer program can be obtained at the RIVM