Comparison and validation of risk assessment tools (FRAC-WECO Deliverable D4.1)

The objective of this document is to review a series of risk assessment tools that were selected in Deliverable 2.5: Decision grid for best approach in terms of modelling concepts/ contaminants. As a reminder, the selection was carried out as follows:
First, most cited risk assessment tools (RA tools) in the literature were selected. In a second step, about thirty softwares were chosen according to their characteristics and their potential usefulness in the scope of the project. The criteria that were taken into account in the selection process are the:
• type of risk concerned (risk on water resources and ecosystems);
• type of contaminants managed by the software (at least the most common ones: hydrocarbons, heavy metals, chlorinated solvents and semi-organic volatile compounds...);
• type of media managed by the software (soil, groundwater and surface water);
• possibility to take into account in a certain way the contaminant fluxes data (hydraulic conductivity, hydraulic gradient, ...);
• possibility to take into account attenuation factors (partitioning between the liquid-, solid- and gaseous phases; re-distribution in the soil profile by sorption; dilution in groundwater; biodegradation);
• complexity of the models (analytical or numerical);
• possibility to use GIS data;
• type of inputs and outputs;
• possibility to calculate uncertainty on the results;
• possibility to calculate cost-benefit from remedial action.
Based on these criteria, several tools have been selected:
• RISC Workbench (http://www.bpRISC.com/index.htm );
• RBCA Toolkit (http://www.gsi-net.com/Software/RBCA_tk_v2.asp ).
In the scope of this document, additional tools have also been included in the selection in order to be tested further. :
• MISP (http://www2.brgm.fr/MISP/);
• Remedial Targets Worksheet (http://www.environment-agency.gov.uk/subjects/landquality/113813/887579/887905/?lang=_e ).
Note that SADA (http://www.tiem.utk.edu/~sada/index.shtml) and FIELDS (http://epa.instepsoftware.com/fields/), initially selected in deliverable 2.5, will not be described in this document because it turned out that they do not have the necessary characteristics to study the transport of dissolved contaminants.
This document is organized as follows. First, a description of selected softwares via their ability to model the transport of dissolved contaminants. Second, a presentation of the two case studies on which each tool will be tested and compared to others. Third, the comparison of results in itself and finally, conclusions and perspectives of the study will be drawn.