Derivation and Use of Risk-Based Action Levels UNDER RCRA Corrective Action at Los Alamos National Laboratory. A. M. Dorries, Los Alamos National Laboratory, Los Alamos, New Mexico; and J. P. McCann, Neptune and Company, Inc., 1505 15th Street, Suite B, Los Alamos, NM 87544
Los Alamos National Laboratory (LANL), an active US Department of Energy research facility, is aggressively pursuing environmental restoration alternatives under RCRA Corrective Action. The derivation and use of human health risk-based action levels, including the screening action level (SAL), the preliminary remediation goal (PRG), and cleanup levels, provide an important basis for determining which sites should be proposed for corrective action, and to what environmental thresholds these sites should be remediated. A streamlined, risk-based decision framework is used in LANL's Environmental Restoration Project. This presentation illustrates how action levels are derived and used in context with this streamlined approach. Addressed are critical factors such as the development of technical assumptions and land use options, the appropriate use of "generic" versus site-specific action levels, the development of special exposure scenarios for Native American risk characterization, and the integration of ecological risk considerations. The calculation of the appropriate concentration terms (statistics) for use in comparing to various action levels, and other factors that impact the derivation and use of action levels including cost/benefit considerations, stakeholder involvement, and technological applications are also presented.