Conceptual Site Model - Argonne National Laboratory

WVDP Phase 1 CSAP• An exception to Duriron piping is the leachate transfer pipeline that runs from the NDA(WMA 7) to Lagoon 1 and Lagoon 2. This is a two inch polyvinylchloride pipeline, buriedapproximately five feet below grade. It runs for approximately 400 feet within WMA 2. Theleachate transfer pipeline originally delivered water that collected in SDA lagoons (WMA 8)to the lagoons in WMA 2. The leachate transfer pipeline currently transfers liquids collectedin the NDA Interceptor Trench to Lagoon 2 for treatment.• All underground wastewater pipelines within WMA 2 are known to be radioactivelycontaminated. The leachate transfer pipeline has been determined to contain an insignificantamount of residual radioactivity.Certain facilities that were located in WMA 2 have been removed during deactivation work toachieve the EIS starting point. These facilities include the O2 Building, the Test and StorageBuilding, the Vitrification Test Facility, the Maintenance Shop, the Vehicle Maintenance Shop,the Maintenance Storage Area, miscellaneous "O" series office trailers, and a group of storagetrailers. Of these facilities, only the O2 Building was radioactively contaminated. Concrete floorslabs and foundations associated with these facilities, except for the trailers, remain in place.B.2 Physical SettingWMA 2 is located on the North Plateau. It is bounded to the west by WMA 1, WMA 3, WMA 5,and WMA 6, to the north by WMA 5 and WMA 4, to the east by WMA 12 South, and to thesouth by WMA 6 and WMA 12 South.The surface of WMA 2 consists of building footprints, parking lots/hardstands, waste lagoons,and vegetated soils. WMA 2 has a complex topography, reflecting the significant reworking ofsoils over the years to install and decommission various waste lagoons and supportinginfrastructure. In general, surfaces slope from the west towards the east. Surface runoff dischargesto ditches that run along the northern and southern boundaries of WMA 2. The northern ditchjoins the Swamp Ditch (WMA 4), which discharges to Franks Creek to the east of the WVDPpremises. The southern ditch feeds Erdman Brook (in WMA 12 South), which also joins FranksCreek.Rev. 1 B-6