Conceptual Site Model - Argonne National Laboratory

WVDP Phase 1 CSAPlater in this section, there is evidence that portions of the surface have been reworked, althoughthe reason is unclear.Figure K.2 shows WMA 12 North in 1962 prior to NFS development. At this time WMA 12North was grassland and woodland.Figure K.3 shows WMA 12 North in 1966. A road leads into WMA 12 North from the southwestand terminates in what appears to be a cleared area. The purpose of the clearing is not known.Based on the fact that in later years ponds are present, this may have been a soils borrow area tosupport construction on the main NFS site.Figure K.4 shows WMA 12 North in 1968. The clearing is more defined than in 1966, as is theentry road from the southwest.Figure K.5 shows WMA 12 North in 1977. Ponds with standing water are present that were not inexistence in 1968. The ponds are located in the previously cleared areas.Figure K.6 shows WMA 12 North in 1984. In this photograph, ponds with standing water areclearly visible.Figure K.7 shows WMA 12 North in 1995. There is no visible change in WMA 12 North since1984.Figure K.8 shows WMA 12 North in 2007. There is no visible change in WMA 12 North since1995.K.4 Known and Suspected ReleasesK.4.1 Cesium ProngPotentially Affected Media:Potentially Affected WMAs:surface soil, subsurface soil, sediments1, 2, 3, 4, 5, 6, 10, 12 (northern portion)Rev. 1 K-2