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Environmental Modeling Community of Practice

About the EPA Center for Exposure Assessment Modeling (CEAM)

The EPA Center for Exposure Assessment Modeling (CEAM) was established in 1987 to meet the scientific and technical exposure assessment needs of the United States Environmental Protection Agency (U.S. EPA) as well as state environmental and resource management agencies. To support environmental risk-based decisions, CEAM provides proven predictive exposure assessment techniques for aquatic, terrestrial, and multimedia pathways for organic chemicals and metals. A wide range of analysis techniques is provided, ranging from simple desk-top techniques suitable for screening analysis, to sophisticated, state-of-the-art continuous simulation models.

CEAM distributes environmental simulation models and databases for urban and rural nonpoint sources, conventional and toxic pollution of streams, lakes and estuaries, tidal hydrodynamics, geochemical equilibrium, and aquatic food chain bioaccumulation. In addition to software distribution, CEAM reviews and evaluates potential and existing software products, maintains and tests source code and command files, and provides user support. User support includes review, evaluation, and possible correction of routine run time errors or other problems encountered when using CEAM software and provides information exchange to assist users applying a model developed for one purpose to a new and different problem.

New software release versions periodically update source code and documentation enhancements or corrections. Maintenance activities focus on improvements and overcoming problems in the operation and application of products, code optimization, and hardware/software portability. Further development, refinement, and extension of model application and theory is a separate research and development activity.

Software products available through CEAM are selected from many candidate products by experienced users in the U.S. EPA regulatory and regional offices and by CEAM staff. Selection criteria include utility and effectiveness, availability of adequate documentation, degree of acceptance and application by users, and adherence to good software development practices.

For more information about CEAM or supported exposure assessment models, visit our distribution and support policy page or browse the frequent questions page. If you would like to provide comments or ask a question, feel free to contact CEAM.