A proposed methodology for evaluating low-level radioactively-contaminated soil

This report was prepared to support the development of residual radioactivity criteria for disposition of contaminated soil locations at the Idaho National Engineering Laboratory (INEL). The criteria is primarily for use in making decisions regarding disposition of sites at the INEL that have low levels of radioactive contamination that are not already in an Operable Unit (OU) or Waste Area Group (WAG) identified under the Federal Facility Agreement and Consent Order (FFA/CO) process in place at the INEL. The report describes the development of screening level concentrations for selected radionuclides in soils in the environment at the INEL. These screening levels are based on environmental conditions at the INEL and are generically applicable to the site. They are intended to provide a consistent technical basis for operational decisions regarding the disposition of sites contaminated with low levels of radioactivity prior to final remediation. They are not intended to be used in lieu of the remediation process defined under the FFA/CO, nor as clean-up levels for locations where remediation is required. This report presents the development of screening levels that are based on a site-specific pathway analysis using the DOE-recommended RESRAD code. RESRAD results for screening level calculations are presented in Appendix A