Life-cycle risk analysis for Department of Energy (DOE) buried wastes.

摘要

Before 1970, hundreds of thousands of cubic meters of transuranic (TRU), low-level, and mixed low-level wastes generated from nuclear materials production were buried at various sites across the U.S. Department of Energy (DOE) Complex. Most of these wastes were buried in shallow unlined pits and trenches and covered with soil creating the potential for contaminant migration and exposure with concomitant safety and health concerns.;Not only is the buried waste inventory large but the waste types are highly variable and often inter-mixed with hazardous wastes making their retrieval, treatment, and disposal highly problematic. For example, many of the TRU constituents buried at these sites possess very long half-lives and can pose hazards through a variety of exposure pathways. Inconsistency in regulatory approach and agreements, including historic DOE management, concerning disposal alternatives (i.e., manage the wastes in-place or retrieve the wastes for treatment and disposal either on- or off-site) provides neither a consistent basis for site remediation nor transparency to a range of stakeholders.;To provide a foundation for risk-informed decision-making, a framework is developed here for the transparent and consistent technical evaluation of the life-cycle risks and risk trade-offs (both to the general public and workers) associated with buried waste disposition and site remediation. Risk is one of the inputs needed (along with costs, technical feasibility, cultural and societal impacts, etc.) to make a risk-informed decision. Use of this framework to provide the risk information needed will differ from existing approaches by providing a basis for evaluating relevant risk tradeoffs involving the general public and workers in a consistent and transparent manner. The framework is applied to the buried wastes areas from two DOE sites with very different climactic conditions.