Ecosystems Research Division

Modeling efforts at ERD primarily focus on simulating the fate and transport of constituents, such as nutrients (nitrogen, phosphorus), sediments (silt, clay, sand), and toxic substances (petroleum products, pesticides, mercury) within watershed areas (saturated and unsaturated soils, groundwater, surface waters, receiving waters). Some researchers here investigate how land-use practices (agriculture, urbanization, riparian zone alteration) affect this process, including alteration of surface water flow dynamics. Other modelers focus on biotic components (soil invertebrates, plants, and fish communities) of natural systems, examining their response to external exposure and internal processing of these substances, as well as, in the case of aquatic communities, the effect of flow regime on their habitat.

Below is a list of models currently under development, or in current use, by scientists here at ERD. Click on any of the active links below to get general information on what the model does, how it's been used, and links to other relevant information concerning that model. Feel free to email us with questions about any of the models listed here!

In addition, information on these models can be found at EPA's Council on Regulatory Environmental Modeling (CREM) site. CREM promotes consistency and consensus within the Agency on mathematical modeling issues including model guidance, development, and application, and enhances both internal and external communications on modeling activities. The CREM is the Agency's central point to address modeling issues.

• Hydrology and Constituent Transport in Surface and Receiving Waters
  • Exposure Analysis Modeling Sytems (EXAMS)
  • HSPF Toolkit for BMP Modeling Applications (FTABLE)
  • Environmental Fluid Dynamics Code (EFDC)
  • Water Quality Simulation Analysis Program (WASP)
  • EPA's Research Object Oriented Oil Spill Model (ERO³S)
  • PLUMES
    
    
• Hydrology and Constituent Transport in Subsurface Waters
  • Wellhead Analytic Element Model (WhAEM)
  • Hydrocarbon Spill Screening Model (HSSM)
  • Modeling Subsurface Petroleum Hydrocarbon Transport (ONSITE)
    
    
• Integrated Multi-Media Modeling
  • Framework for Risk Analysis in Multimedia Environmental Systems/Multi-media, Multi-receptor, Multi-pathway Risk Assessment (FRAMES/3MRA)
    
    
• Ecological Endpoint Modeling
  • Aquatic Toxicity Model (AQUATOX)
  • Bioaccumulation in Aquatic Systems Simulator (BASS)
  • Riparian Ecosystem Management Model (REMM)
  • Watershed Modeling Tools under Development
    
    
• Uncertainty and Sensitivity Analyses
  • Supercomputer for Modeling of Uncertainty and Sensitivity Evaluation (SuperMUSE)
    
    
• Computational Chemistry
  • Sparc Performs Automated Reasoning in Chemistry (SPARC)
    
    
• Land Cover Characterization and Change
  • Impervious Cover
    
    
• Redox and Nitrogen Speciation in Subsurface Waters
  • Kinetic Control of Oxidation State
  • Nitrogen Speciation
    
    
• Model Evaluation