Superfund Groundwater Remedy Performance

The US Environmental Protection Agency (EPA) Superfund statutes, policy and guidance define Superfund’s groundwater cleanup mission by providing an expectation that groundwater will be returned to its beneficial use. In this presentation EPA will present the findings of an analysis of groundwater remedy performance at selected Superfund sites, ranging from less difficult cleanups involving small dilute groundwater plumes in simple hydrogeologic settings, to more difficult cleanups such as large plumes with high concentrations, complex hydrogeologic settings, and dense nonaqueous phase liquids. The study examines key aspects of the groundwater remedies, including progress towards achieving remedial action objectives (RAOs), cleanup approaches applied, contaminants addressed, hydrogeology, and the magnitude of cleanup. Results of this analysis show that, for the range of Superfund sites and plumes studied, there have been significant reductions in contaminant concentrations and plume size, and in some cases, the groundwater plumes have been remediated to stringent RAOs, including those based on federal and state drinking water standards.