Conceptual Site Model - Argonne National Laboratory

WVDP Phase 1 CSAPD.3 Area HistoryWMA 4 was not used for any structural purposes during the lifespan of the NFS reprocessingactivities on-site or for any WVDP-related activities other than solid waste disposal in the CDDL.The surface drainage features have been reworked over time to accommodate the CDDL.Figure D.2 shows WMA 4 in 1962 prior to site development. At this time WMA 4 was grasslandand woodland with a marsh or pond in the vicinity of what is now the southwestern corner of theCDDL.Figure D.3 shows WMA 4 in 1966. Development of WMA 5 and WMA 2 is visible. Apart fromsome surface scarring in what is now the eastern end of the CDDL that potentially indicateslimited disposal operations, there are no visible impacts in WMA 4.Figure D.4 shows WMA 4 in 1968. There is no visible change from 1966.Figure D.5 shows WMA 4 in 1977. Additional development of the CDDL area is visible. Inparticular there is some surface scarring, and what appears to be a trench or linear drain installedfrom southwest to northeast across what is now the CDDL footprint, presumably to improvedrainage of the area, and a similar parallel feature to the north of the present CDDL footprint.Figure D.6 shows WMA 4 in 1984. In this photograph, the CDDL has significantly expanded,with placement of material visible. In the eastern end of the CDDL footprint, flowinggroundwater discharge is visible.Figure D.7 shows WMA 4 in 1995. Disposal operations in the CDDL were terminated inDecember 1984 and the closure of the landfill was certified complete by NYSDEC in 1986. Thecurrent configuration of the Swamp Ditch is visible. The Lag Storage additions in WMA 5 havealso been completed adjacent to WMA 4.Figure D.8 shows WMA 4 in 2007. There is no visible change in WMA 4 since 1995.Rev. 1 D-2