Conceptual Site Model - Argonne National Laboratory

WVDP Phase 1 CSAPB.9.3Surface Soil SamplingSurface soil sampling will be used to address areas inaccessible to GWS data collection, toresolve hot spots identified by the GWS data, to evaluate the presence, absence, and/or extent ofsurface contamination above surface soil CG w requirements based on GWS results, and toevaluate contamination in the 0-1 m interval for areas where surface soils have been disturbed.• Wetlands. It is possible that standing water will be present in wetlands that prevent GWSdata collection from those areas. Soil sampling will be required for wetland footprints andfor any other areas where standing water prevents the collection of GWS data. WithinWMA 2, this is most likely to occur in the eastern portion of the WMA.For every area where standing water or saturated soil conditions prevent GWS datacollection and that is outside the planned WMA 2 excavation, systematic soil samplingwill take place. For wetland areas less than 200 m 2 in size, one sample will be collected.For areas between 200 and 1,000 m 2 in size, one sample per 200 m 2 will be collected. Forareas between 1,000 and 2,500 m 2 in size, five samples will be collected. For areasexceeding 2,500 m 2 in size, at minimum one sample will be collected per 500-m 2 area.One sample will be collected from each location representative of a 0-15 cm depthinterval. In the case where an area has more than one location, locations will be selectedto provide systematic coverage of the area of interest. [contingent]• Hot Spots. If GWS data indicate the presence of contamination that possibly exceeds“hot spot” (CG emc ) standards or an isolated elevated area is identified that appearsindicative of a discrete release, the location of concern will be sampled with a biasedsample. Within WMA 2, hot spots will be biased sampled if they are outside the plannedWMA 2 deep excavation footprint. If biased samples are collected from a particularlocation, they will be collected from two depth intervals: 0-15 cm, and 15 cm-1 m. The0-15 cm samples will be analyzed for the 12 radionuclides of potential interest in additionto the 18 ROI. One down-hole gamma scan will be conducted from each biased location.The purpose of these samples is to resolve GWS anomalies, evaluate the appropriatenessof the current ROI list, and verify the absence of additional ROI. [contingent]Rev. 1 B-19