Conceptual Site Model - Argonne National Laboratory

WVDP Phase 1 CSAPLiquid that collects in the sump is routinely sampled, analyzed, and transferred to the Low LevelWaste Treatment Facility in WMA 2 for treatment and release. Treated wastewater is dischargedfrom Lagoon 3 in WMA 2 to Erdman Brook through a permitted outfall (SPDES WNSP001).The Liquid Pretreatment System consists of seven tanks made of carbon steel: one 5,000-gallonholding tank, two 1,000 gallon pre-filtration holding tanks, two 700-gallon tanks containinggranular activated carbon, and two 1,000-gallon post-filtration holding tanks. The granularactivated carbon tanks are housed in a wooden shed 12 feet long by 10 feet wide. The other fivetanks are located in a Quonset-style building.NDA Hardstand. The NDA Hardstand is located near the southeast corner of the NDA.It was an interim storage area where radioactive waste was staged before being disposed. TheNDA Hardstand is radiologically contaminated.The NDA Hardstand originally was a three-sided structure with cinder block walls, located on asloped pad of crushed rock 20 feet wide and 20 feet long. The block walls were removed down tocrushed rock pad in September 2006. The crushed rock pad will be removed during Phase 1decommissioning.Inactive Plant Water Line. A buried eight-inch diameter cast iron water line from the plant runsalong the southwestern border of the NDA.The Plant Water Line was formerly used to supply clean water from the reservoirs to the ProcessBuilding, but was taken out of service in 1986 and capped with cement.Leachate Transfer Line. The Leachate Transfer Line is a two-inch diameter buriedpolyvinylchloride pipeline that runs along the northeast and northwest sides of the NDA,continues northward across WMA 6, and terminates at Lagoon 2 in WMA 2. The total length ofthe line is 4,000 feet.The Leachate Transfer Line has two sections. The section of the line described above is currentlyused to transfer groundwater from the NDA Interceptor Trench sump to Lagoon 2. There also isan inactive section of the line that runs from the SDA lagoons to the Interceptor Trench sump; theRev. 1 G-4