Conceptual Site Model - Argonne National Laboratory

WVDP Phase 1 CSAPB.4.3.3Neutralization Pit OverflowPotentially Affected Media:Potentially Affected WMAs:surface soil, subsurface soil, groundwater1, 2, 3, 4, 5, 6 (North Plateau Groundwater Plume)In 1987, the Neutralization Pit overflowed due to a malfunctioning drain valve. The overflowwent to the ground near the New Interceptors and Lagoon 1. The flow was stopped when notedby an operator. Approximately 5,000 gallons of wastewater were spilled, with approximately 5E-05 uCi/mL gross beta (DOE 2009 Table 2-18). This release likely has contributed to the NorthPlateau Groundwater Plume.B.4.3.4Interceptor Drain Line LeakPotentially Affected Media:Potentially Affected WMAs:subsurface soil, groundwater1, 2, 3, 4, 5, 6 (North Plateau Groundwater Plume)In 1967, contaminated groundwater was encountered during construction of the New Interceptor,which was being constructed south of the Old Interceptor. This contamination indicated leakageor a release associated with the Old Interceptor drain line (DOE 2009 Table 2-17). This releaselikely has contributed to the North Plateau Groundwater Plume.B.4.3.5Waste Transfer FailurePotentially Affected Media:Potentially Affected WMAs:subsurface soil, groundwater1, 2, 3, 4, 5, 6 (North Plateau Groundwater Plume)In 1967, the wastewater line to Tank 8D-2 (Line 7P-170-2A) failed during waste transfer from theProcess Building (in WMA 1) to the tank (in WMA 3). The failure resulted in approximately 555gallons of liquid waste entering an acid recovery sump in the southwest corner of the ProcessBuilding and draining to the Old Interceptor. Resultant activity levels at the Old Interceptor weregreater than 100 mR/hr. The waste required pump-out back to the Process Building for treatment.This event led to installation of 12 inches of concrete shielding on the Old Interceptor floor. In2003, a gamma radiation level of 408 mR/h was measured near the Old Interceptor tank floorRev. 1 B-12