Conceptual Site Model - Argonne National Laboratory

WVDP Phase 1 CSAPThe number of cores is based on the number of samples required to obtain relatively accurate soilvolume estimates. For the purposes of this analysis, “relatively accurate” for every potentialwaste stream is defined as a volume estimate error no more than 10% of the total excavatedvolume. Using this definition along with a Bernoulli trial/binomial distribution analysis indicatesa minimum of 100 systematically placed samples is required to meet this objective (e.g., 10samples from 10 soil core locations). Table 4 provides the relative volume estimation errorexpected with 100 systematic samples under different contamination probability assumptions.The “contamination probability” identified in Table 4 can be interpreted as the fraction of thetotal excavation volume that meets a particular waste stream definition. The “relative error” is theratio of the expected error associated with estimating the contamination fraction based on 100systematic samples to the expected volume of contamination. While relative errors grow ascontamination probabilities become smaller, absolute errors shrink and never exceed 10% of thetotal excavated volume if 100 systematic samples are collected.Table 4: Soil Sample Numbers for Volume EstimationVolume Error Relative toContaminationProbabilityNumber ofSamplesContaminationVolumeTotal ExcavationVolume0.50 100 0.20 0.100.40 100 0.24 0.100.30 100 0.30 0.090.20 100 0.39 0.080.10 100 0.59 0.066.10 Verify Contamination Status of Soils To Be Affected by Phase 1 Construction NeedsThere will be areas of the WVDP premises that will be used to support Phase 1 decommissioningactivities. Examples of these areas include lay-down areas that may be used for excavated soilstaging, as necessary. When these areas are identified and prior to their use in support of Phase 1decommissioning activities, the contamination status of surface soils in the areas needed tosupport Phase 1 decommissioning activities will be determined.Rev. 1 44