Evaluation and refinement of multimedia/multipathway human and ecological exposure assessment methods and applications in support of rational decision making for short- and long-term stewardship

This project provides tools to support emergency response planning as well as tools for quantifying relative contributions of on-site, local, and regional releases of contaminants of concern to observed near-site exposures (e.g. mercury in fish). Some specific efforts being pursued under this project are:

• A set of GIS-based modules are being developed to process available databases (from USGS, Forest Service) and derive the inputs required for the forest fire model. Another GIS-based module is being developed to facilitate the characterization of potential population exposures associated with the fire events.
• Evaluation of the adequacy of the methods and models used by DOE to reconstruct historic and assess potential (future) exposure to atmospheric releases of radionuclides and chemical contaminants vis-a-vis new developments in the understanding of the processes.
• Development of an integrated source-to-dose exposure model that accounts for the local and remote sources of mercury and their relative contributions to the environment and the ecosystem of SRS; this model attempts to quantify the hydrogeologic cycling of mercury at SRS, and estimate dose to humans based on levels of mercury in environmental media and aquatic biota. The most up-to-date US EPA inventories and models for mercury emissions and transport/transformation are employed in this effort. These include the new national mercury emissions inventory and REMSAD version 7 for regional transport. The latest model of the BASINS model is used to describe watershed dynamic changes. New PBPK models for mercury, developed at CRESP-CEEA are used to calculate (and apportion according to source) the delivered doses.