Environmental Hazard Assessment for Transportation-Related Chemicals

Project summary:

A decision support tool was developed that enables MnDOT personnel to judge the potential risk associated with new or replacement chemicals used in roadway construction and maintenance, or as a result of direct vehicle use. This risk management tool consists of: (1) a multimedia fate and transport model that is applicable to persistent and short-lived chemicals; (2) GIS linkage that enables definition and display of spatially referenced input and output data; and (3) a toxicological assessment module that estimates exposure and potential risk to ecosystem health (including humans). The project?s objectives were to determine cumulative risk due to the presence of chemicals entering the environment, and incremental risk associated with that portion of chemical attributable to transportation activities.

The general model was developed and then applied to simulate conditions in Minneapolis/St. Paul using existing GIS information. The fate model was calibrated and tested with relevant data obtained from the literature and a field sampling program. Progress was assessed and advice sought through several workshops held with MnDOT staff and experts. The final risk management tool was presented to Mn/DOT in a user-friendly format suitable for use on a personal computer. It is anticipated that in the future the model will be extended to cover all or most ecoregions across the state using geographically specific data that will enable MnDOT to meet its mandate for statewide environmental protection. The unique features of the tool include: its specificity for chemicals related to transportation systems, its applicability to a wide range of chemicals including persistent and short lived species, its geographic specificity for an urban suburban area, and its linkage to a GIS that will allow use and display of spatially referenced data and results. A user's guide for the software is also available.