Conceptual Site Model - Argonne National Laboratory

WVDP Phase 1 CSAP3. Contaminated soil was removed (DOE 2009 Table 2-18; DOE 2010 Section 3.11.5). Thisrelease likely has contributed to the North Plateau Groundwater Plume.B.4.3.8Interceptor System Operational ReleasesPotentially Affected Media: surface soil, subsurface soil, groundwaterPotentially Affected WMAs: 1, 2During NFS operations, several incidents such as inadvertent transfers of higher-than-intendedactivity occurred in the Interceptor system, upstream of the Lagoons. Documented accounts ofleakage and spills in the Interceptor area corroborate the generally elevated observed subsurfacesoil contamination in the area between Lagoon 1 and the Process Building (WMA 1). Localizedsubsurface soil contamination can be attributed to these unintended operational releases.B.4.3.9Lagoons 5 Area Soil ContaminationPotentially Affected Media: surface soil, subsurface soilPotentially Affected WMAs: 2In 1997, a small spot of relatively high-activity, previously unidentified soil contamination wasfound in WMA 2, north of Lagoon 5. This contamination was identified during a radiologicalsurvey near environmental characterization activities (DOE 2010 Section 3.11.5).B.5 Existing DataExisting data sets for this area include:• In 1982 static direct exposure readings were collected across the WVDP premises(WVNSCO 1982). A portion of WMA 2 was covered by these measurements on a 10-mgrid. Figure B.12 shows these results color-code by the exposure readings encountered.These data indicated potentially significant surface contamination within the WMA 2boundary, with activity levels in general falling as one moves from west to east;interpretation of these data is complicated by the possibility of shine effects from theProcess Building and other facilities.Rev. 1 B-14