ENVIRONMENTAL REMEDIATION DECISION-MAKING FOR BEAR CREEK VALLEY AT THE U.S. DEPARTMENT OF ENERGY OAK RIDGE RESERVATION IS FACILITATED UNDER A WATERSHED APPROACH

摘要

Managing environmental releases within Bear Creek Valley at the U.S. Department of Energy’srnOak Ridge Reservation in Oak Ridge is being facilitated through a watershed managementrnapproach. Under this approach, all sources of environmental contamination within the BearrnCreek watershed are evaluated concurrently. Then comprehensive remedial alternatives forrneliminating or otherwise controlling these contaminant sources are developed to meet watershedbasedrnremedial action objectives. The Bear Creek watershed is a 2800-acre area whererngroundwater is confined by two ridges and the surface water and groundwater systems arerninterconnected through a common exit pathway. The eastern third containing numerous disposalrnareas previously used for waste management by the Oak Ridge Y-12 Plant. Addressing BearrnCreek Valley as a watershed is premised on the fact that the multiple disposal areas are releasingrncontaminants into common groundwater and surface water exit pathways. The watershedrnapproach allows for an evaluation of these releases collectively and development of remediationrnstrategies that address their cumulative impact. Once the remediation strategies are defined arnsingle decision can be made that identifies the most effective set of remedial actions. Thernbenefits of this strategy include: 1) environmental remediation objectives for the entire BearrnCreek Valley are established to be consistent with all legal requirements; 2) releases from thernindividual disposal areas are evaluated within the context of overall watershed contaminationrnchallenges, allowing prioritization of cleanup activities, a coordinated technical approach, andrnallocation of limited cleanup resources; and 3) a significant reduction in documentation costs andrnschedule associated with remedy selection. Under the watershed approach, multiple potentialrnremediation objectives, ranging from full restoration of the entire valley to achieve conditionsrncompatible with unrestricted future development to simply maintaining existing conditions in thernvalley were evaluated in a feasibility study. From this range of objectives, a decision regardingrnthe best remediation strategy was determined for Bear Creek Valley. This decision defines arnclear, consistent vision for use of the valley at the conclusion of cleanup activities, is protectivernof human health and the environment, complies with applicable or relevant and appropriaternrequirements, is cost-effective, and has broad public support.