Variability of Kd Values in Cementitious Materials and Sediments

Sulfur speciation in untreated and alkali treated ground-granulated blast furnace slag

“…Tables Table-1. Chemical composition of artificial LLNW simulant used in saltstone preparation at the U.S. DOE Savannah River Site (Almond et al, 2012;Reigel, 2011). The solution was passed through a 0.2 µm PVDF filter prior to the use.…”

“…In assessing the stability of S species in fresh and aged CST, two Ca-bearing solutions were selected to simulate a simplified porewater in contact with a fresh cement (0.017 M Ca(OH) 2 at pH 11.3± 0.12) where the cement chemistry was controlled predominantly by portlandite, and an aged (thousands of years) cement (0.001 M CaCO 3 at pH 8.25 ± 0.02), where the systems chemistry is controlled predominately by calcite (Criscenti et al, 1996, Krupta et al, 2012. The chemical composition of this non-radioactive LLNW simulant solution is listed in Table-1 and was designed to represent the non-radioactive waste generated at the Savannah River Site (Almond et al, 2012;Reigel, 2011). Approximately 4 g of dry GGBFS was reacted with 40mL of alkali solutions, 0.001 M CaCO 3 prepared in oxygenated ultrapure water, and of 0.017 M Ca(OH) 2 that was prepared in boiled/degassed ultrapure water.…”

Updated Liquid Secondary Waste Grout Formulation and Preliminary Waste Form Qualification

“…A Ca(OH)2-saturated solution pre-equilibrated with 0.3-2 mm size-reduced T7 monolith material was used for all 99 Tc sorption and desorption experiments. The pre-equilibration step was used to prevent large changes in pH and aqueous chemistry composition during the sorption phase in hopes of minimizing other processes, such as 99 Tc precipitation, that could affect the desorption behavior and change the pH of the Ca(OH)2-saturated solution (Almond et al 2012, Kaplan 2010. The Ca(OH)2-saturated solution simulates young/moderately aged cement pore solution and was prepared by adding approximately 15 g of reagent grade Ca(OH)2(s) to 1.5 liters of DIW that had been purged with N2 (98%) and H2 (2%) gases.…”

Building 235-F Goldsim Fate And Transport Model

“…Distribution coefficients (K d s) for these materials will be assigned based primarily upon Kaplan 2010, and modified with work subsequent to Kaplan 2010 including Seaman and Kaplan 2010, Kaplan 2011, Almond et al 2012, and Powell et al 2010.…”

“…The cementitious leachate-impacted sediment environment is defined as clayey or sandy sediment between a cementitious waste form or structure and the aquifer. A "1-m high cementitious slab would be expected to alter the buffering capacity all the way down to the water Kaplan 2011, Almond et al 2012, and Powell et al 2010. Table 3-23 also provides the apparent solubilities of each of the elements in an oxidizing cementitious material environment.…”