Overview of the Multimedia Environmental Pollutant Assessment System. Environmental Restoration Program

摘要

This report describes the Multimedia Environmental Pollutant Assessment System (MEPAS) computer model designed by Pacific Northwest Laboratory for use in evaluating the health risks associated with US Department of Energy (DOE) waste sites. This report has been prepared to provide DOE Oak Ridge Field Office personnel with a simplified explanation of MEPAS and an understanding of how MEPAS is used to quantify potential risks to human health. The scope and limitations of the MEPAS model are presented, and the possible contaminant release media and transport pathways are outlined. The two main types of health indexes generated -- the hazard potential index (HPI) and the maximum individual index are described; and calculations used to obtain these indexes are presented. Guidance on interpretation of the HPI is also included. Finally, the HPI calculations for 3 contaminants in a hypothetical environmental problem are demonstrated.