Mission Statement

Over the past few decades, federal regulatory agencies have promulgated rules and guidance for the remediation of sites where human activities have resulted in environmental contamination with radioactivity. These have covered, among other things, the Environmental Protection Agency’s (EPA) oversight of CERCLA cleanup; the Nuclear Regulatory Commission’s (NRC) responsibility for the decontamination and decommissioning of its licensed facilities and sites; the Department of Energy’s (DOE) initiative in cleaning up the nuclear weapons complex left over from the Cold War; and the Department of Defense's (DoD) environmental remediation of its own sites to be compliant with pertinent federal regulations.

For all of these activities, and whether in administering guidance or in demonstrating compliance, it is necessary to ensure that decisions that involve protection of human health and environmental safety are risk-informed. One key approach to providing the necessary information is to employ contaminant fate and transport computer simulation to predict radiation exposures, doses, and possible risks to potential receptors now and in the future. The agencies have all developed and use their own modeling programs, however, and although these are often similar, there are noteworthy differences. This can lead to different agencies analyzing the same site and finding differences in the resulting dose and risk estimates.

A contributing cause of these differences is the choice of — and inherent variability and uncertainty in — the model parameter values and distributions utilized. Thus, it is often suggested that the reliability of such modeling efforts could be enhanced through the availability of a national data repository of environmental modeling parameter values and distribution of known provenance and demonstrated utility. To this end, the Cleanup Sub-Committee of the Interagency Steering Committee On Radiation Standards (ISCORS) is providing this catalog of environmental parameter information sources.