Conceptual Site Model - Argonne National Laboratory

WVDP Phase 1 CSAPdown-hole gamma scan conducted at the center of the location with static measurementstaken every 15 cm. [contingent]• If a surface soil sample indicates contamination impacts above background levels for the15 cm-1 m depth interval, an additional sample from a depth of 1-2 m will be collectedand analyzed from that location. This process will continue until the vertical extent ofcontamination above background is bounded. One down-hole gamma scan will beconducted from each soil location requiring deeper investigation with a static readingtaken every 15 cm vertically. The purpose of these samples is to define the vertical extentof contamination. [contingent]H.9.4 Drainage Feature SamplingWMA 9 contains three distinct drainage features. For drainage features within WMA 9, thesurface soil CG w requirements apply. Surface drainage feature sampling will be conducted todetermine ditch sediment contamination status relative to surface soil CG w requirements. Surfacedrainage features will be sampled as follows:• Samples representing a 0-15 cm depth interval will be collected from ditch sediments. InWMA 9, the three ditches have a combined length of approximately 420 m. Samples willbe systematic located using a random start, separated by 30 m. [required]• If any 0-15 cm sample result indicates contamination impacts above background levels, a15 cm-1 m sample will be collected from that location following the protocols used forthe original 0-15 cm sample. [contingent]• If a sample indicates contamination impacts above background levels for the 15 cm-1 mdepth interval, an additional sample from a depth of 1-2 m will be collected and analyzedfrom that location. This will be repeated, as necessary, until the vertical extent ofcontamination impact is bounded at that location. [contingent]H.9.5 Required Laboratory AnalysesAll samples will be submitted for analysis of all 18 ROI.Rev. 1 H-9