Technetium, Iodine, and Chromium Adsorption/Desorption Kd Values for Vadose Zone Pore Water, ILAW Glass, and Cast Stone Leachates Contacting an IDF Sand Sequence

Integrated Disposal Facility FY 2016: ILAW Verification and Validation of the eSTOMP Simulator

“…In this simulation CO 2 (g) was not included as a fixed concentration species; the only source of dissolved CO 2 is applied irrigation water. This assumption is consistent with the updated conceptual model of glass within the backfill material that was reported in Last et al (2015)., which utilized 'no assumption that gas phase CO 2 was fixed at atmospheric levels' (p. 3.2). The fixed CO 2 assumption that had been used in earlier reports was inconsistent with reactions that consume CO 2 (g), and a near-surface recharge rate that was higher than that assumed in previous PA calculations (Bacon and McGrail 2001;2.19 2005).…”

“…The solid species are listed in Table 2.6. The mineralogical composition for the backfill was based on samples from borehole C3177 (299-E24-21) (Horton et al 2003) as described by Last et al (2015). Missing molar volume data was added to the thermo.com database for anatase, baddelleyite, illite and Zn(OH)2(gamma) (webmineral.com).…”

“…Ion exchange reactions were modeled assuming the Gaines-Thomas convention (Gaines and Thomas, 1953). The ion exchange coefficients are based on the measured cation exchange capacities for samples from borehole 299-E33-44 (Last et al 2015). Ion exchange of four species are considered: Na + , Ca 2+ , K + , and Mg 2+ .…”

Solid Secondary Waste Data Package Supporting Hanford Integrated Disposal Facility Performance Assessment

“…The core of the conceptual model used to describe COPC geochemistry in cementitious environments was taken from Atkinson et al (1988) and has been proposed in previous Hanford data packages (Krupka et al 2004;Last et al 2015;Cantrell et al 2016), as well as at the SRS (Kaplan 2016), and in Europe (Ochs 2016;Wang et al 2009;Cronstrand and Power 2005). There is extensive research supporting the underpinnings of this model, which describes three types of physicochemical aging environments, or stages, that all cementitious materials generally progress through (Figure 8-2).…”

Secondary Waste Cementitious Waste Form Data Package for the Integrated Disposal Facility Performance Assessment

“…This data package compiles available data necessary for modeling the performance of cementitious waste forms for aqueous waste streams as part of the IDF PA and is an update to and supersedes the cementitious waste form data package prepared by Cantrell (2015). Other data packages have been prepared in the past for the ILAW glass and cementitious waste forms and have recently been updated (Krupka et al 2004;Rockhold et al 2015, Last et al 2015, Pierce et al 2004, Freedman et al 2015. A separate data package is being prepared for solid secondary wastes encapsulated in cementitious waste forms (Flach et al 2016).…”