Conceptual Site Model - Argonne National Laboratory

WVDP Phase 1 CSAP(e.g., remedial support and FSS). Data collection is required to determine area-specificradionuclide ratios and determine their consistency. These data would be used to supportthe use of surrogates, if the results indicate this is appropriate.4. Establish Background Data Sets. The Phase 1 DP calls for background surveys to beperformed to establish surface soil background conditions in known non-affected areas.Background survey data are necessary for interpreting gross activity scan results and fordetermining when CSAP soil results are inconsistent with background assumptions andmay be useful for FSS analysis depending on the type of statistical test used to establishcompliance with wide-area DCGL (DCGL w ) requirements. Surface soil background datacollection will take place from an appropriate area near or within the WVDP premises,possibly an area that has been used to collect previous background data for the WVDPpremises.5. Determine Extent of Surface Soil Contamination. The lateral and vertical extent ofsurface soil contamination (represented by the top 0-1m of soil) present at activityconcentrations that would require an action based on the ROI list and associated surfacesoil DCGLs contained in the Phase 1 DP is unknown. Data collection is required todetermine the extent of contamination. These data would become the basis for potentialexcavation footprints (discretionary in Phase 1) and volume estimates that can be used forprogrammatic planning purposes (i.e., costing, identifying appropriate disposal optionsand appropriate material handling needs, and so forth), and for FSS design and support inthose areas where remediation will, ultimately, be unnecessary.6. Identify the Presence/Absence of Subsurface Soil Contamination. The presence/absenceand vertical depth (where present) of soil contamination in areas outside the plannedWMA 1 and WMA 2 excavations is unknown. Data collection is required to determinepresence and extent of contamination outside the planned WMA 1 and WMA 2excavations. These data may be used to adjust DCGL derivations contained in the Phase1 DP for subsurface soils and would be used to identify areas suitable for Phase 1 FSSdata collection (i.e., areas where surface contamination appears to meet DCLGrequirements and subsurface contamination is absent). These data would also be used todetermine whether thin layers of highly elevated contamination are present in the top 1-msoil profile that would pose dose concerns if exposed but that may not be identified byRev. 1 4