I'm researching methods for modeling oil spills on land using ArcGIS. I've looked into ArcHydro and it seems to have some tools I can utilize for the movement of oil over terrain. I've also looked briefly into HEC-GeoRAS / HEC-GeoHMS for water movement in river systems. Can these programs be used to model spills at a given point outside of a river system? Any information will be helpful.
Are there other tools that would help model this process?