Risk evaluation of remedial alternatives for the Hanford Site

Risk assessment is one of the many tools used to evaluate and select remedial alternatives and evaluate the risk associated with selected remedial alternatives during and after implementation. The risk evaluation of remedial alternatives (RERA) is performed to ensure selected alternatives are protective of human health and the environment. Final remedy selection is promulgated in a record of decision (ROD) and risks of the selected alternatives are documented. Included in the ROD documentation are the risk-related analyses for long-term effectiveness, short-term effectiveness, and overall protection of human health and the environment including how a remedy will eliminate, reduce or control risks and whether exposure will be reduced to acceptable levels. A major goal of RERA in the process leading to a ROD is to provide decision-makers with specific risk information that may be needed to choose among alternatives. For the Hanford Site, there are many considerations that must be addressed from a risk perspective. These include the large size of the Hanford Site, the presence of both chemical and radionuclide contamination, one likelihood of many analogues sites, public and worker health and safety, and stakeholder concern with ecological impacts from site contamination and remedial actions. A RERA methodology has beenmore » promulgated to (1) identify the points in the process leading to a ROD where risk assessment input is either required or desirable and (2) provide guidance on how to evaluate risks associated with remedial alternatives under consideration. The methodology and evaluations parallel EPA guidance requiring consideration of short-term impacts and the overall protectiveness of remedial actions for evaluating potential human health and ecological risks during selection of remedial alternatives, implementation of remedial measures, and following completion of remedial action.« less