Conceptual Site Model - Argonne National Laboratory

WVDP Phase 1 CSAPAPPENDIX JWMA 12 (SOUTHERN PORTION) PRE-REMEDIATION DATA COLLECTIONJ.1 BackgroundThe southern portion of Waste Management Area 12 (WMA 12 South) is approximately 42 acresin size. Along with the northern portion of Waste Management Area 12, it contains the balance ofthe WVDP premises not included in one of the other WMAs (see Figure J.1 for map).J.2 Physical SettingWMA 12 South is primarily located on the South Plateau. It is bounded to the east by the WVDPfence line, to the north by WMA 2, to the west by WMA 6, and to the south by WMA 7, WMA 8,and the WVDP fence line.WMA 12 South is vegetated. Its primary topographical features are associated with ErdmanBrook and Franks Creek. Both streams incise fairly deep gullies into the land surface, and are fedby intermittent drainage features scattered across WMA 12 South. Erdman Brook and FranksCreek are two of the primary drainage features within the WVDP premises.The WMA 12 South area is underlain by the weathered and unweathered Lavery Till. Theweathered Lavery Till allows some groundwater movement. The unweathered Lavery Till is animpermeable unit. The two streambeds are incised into the Lavery Till. Groundwater within theweathered Lavery Till predominately discharges to the two streams. Within the unweatheredLavery Till there is a layer known as the Kent Recessional Series that is more permeable and thatdoes transport groundwater. Groundwater within the Kent Recessional Series, in general, movesto the east/northeast.WMA 12 South has a few man-made features. A buried natural gas line services the West ValleyDemonstration Project. The line crosses Frank’s Creek on the east side of the SDA, then crossesErdman Brook just north of the SDA, and continues across WMA 12 to WMA 1. An activelyused, buried leachate transfer line is used to transfer leachate from the NDA interceptor trench(WMA 7) to the Liquid Waste Treatment Facility (WMA 2). The transfer line crosses ErdmanRev. 1 J-1