Geologic Data Package for the 2005 Integrated Disposal Facility Waste Performance Assessment

Abstract

This data package is a compilation of existing geologic data from the Integrated Disposal Facility Site for use in the 2005 Performance Assessment. The data were compiled from both surface and subsurface geologic sources. The surface mapping has been published previously. The quality and uncertainty of the data are discussed. The 2004 report was modified to include results of studies of the shearwave velocity of sediments at and near the IDF site, which were performed for the Waste Treatment Plant and groundwater monitoring wells 299-E17-26 and 299-E24-24. The conclusions of the original report have not changed with the new data.

Geology Data Package for the Single-Shell Tank Waste Management Areas at the Hanford Site

“…The purpose of this report is to provide the most recent geologic information available for the SST farms and the Integrated Disposal Facility (IDF). This report builds upon previous reports on the tank farm geology ) and IDF geology (Reidel 2005) with information available after those reports were published. Horton (2007) recently published a companion report to this one that discusses the groundwater flow and contamination beneath the SST farms.…”

Tier II Analysis of Vadose Zone Sediments from UPRS 200-E-81 and 200-E-86

“…For one reason, paleosols are discontinuous as shown in Figure 12. The Layer 1 paleosol ( Figure 1A) was only identified in 5 of 26 wells (<20%) in the vicinity of IDF (Reidel 2005). The younger Layer 2 paleosol ( Figure 12B) was identified in 16 of the same 25 wells (64%) around the IDF.…”

“…No other crystalline phases were detected by XRD as being present in the clay fractions. Reidel (2005) attempted to correlate two paleosols observed in the vicinity of the IDF facility within the southern 200 East Area (Figure 12). Immature paleosols (buried soil horizons) were identified as thin layers (several inches to 1 ft thick), with evidence of bioturbation and weak calcic horizons, representing short periods of subaerial weathering (few dozen to few hundred years) between cataclysmic Ice Age floods, which deposited the Hanford formation in the Pasco Basin.…”

“…The discontinuous nature of the paleosols is not surprising considering their extremely thin nature and difficulty in identifying weak paleosol horizons in boreholes. For the present exercise, the tops of the paleosols, reported in Reidel (2005) were added to Figure 12 and hand contoured; this contoured surface was projected northeastward toward C Tank farm. In Figure 12A the Layer 1 paleosol appears to dip moderately toward the northeast.…”

Plume Delineation in the BC Cribs and Trenches Area

“…Reports generated in support of the Integrated Disposal Facility (e.g., Reidel 2004) comprise the most comprehensive characterization data for a physical analog to the BC Cribs and Trenches. The sedimentary units described in Reidel (2004), to the depth covered in this report, include the sand-dominated facies of the Hanford formation, which has been locally divided into three layers. The layers are separated by paleosols that have not been correlated outside of the Integrated Disposal Facility, but appear to extend into the BC Cribs and Trenches Area.…”