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R. C. Bartholomay

Publications and source records attributed to R. C. Bartholomay.

At least 19 recordsLinked to original sources

Determination of variables in the prediction of strontium distribution coefficients for selected sediments

Idaho State University and the US Geological Survey, in cooperation with the US Department of Energy, conducted a study to determine and evaluate strontium distribution coefficients (Kds) of subsurface materials at the Idaho National Engineering and Environmental Laboratory (INEEL). The Kds were determined to aid in assessing the variability of strontium Kds and their effects on chemical transport of strontium-90 in the Snake River Plain aquifer system. Data from batch experiments done to determine strontium Kds of five sediment-infill samples and six standard reference material samples were analyzed by using multiple linear regression analysis and the stepwise variable-selection method in the statistical program, Statistical Product and Service Solutions, to derive an equation of variables that can be used to predict strontium Kds of sediment-infill samples. The sediment-infill samples were from basalt vesicles and fractures from a selected core at the INEEL; strontium Kds ranged from ???201 to 356 ml g-1. The standard material samples consisted of clay minerals and calcite. The statistical analyses of the batch-experiment results showed that the amount of strontium in the initial solution, the amount of manganese oxide in the sample material, and the amount of potassium in the initial solution are the most important variables in predicting strontium Kds of sediment-infill samples.

Environmental Geology↗

Chemical and physical properties affecting strontium distribution coefficients of surficial-sediment samples at the Idaho National Engineering and Environmental Laboratory, Idaho

The U.S. Geological Survey and Idaho State University, in cooperation with the U.S. Department of Energy, conducted a study to determine strontium distribution coefficients (K d s) of surficial sediments at the Idaho National Engineering and Environmental Laboratory (INEEL). Batch experiments using synthesized aqueous solutions were used to determine K d s, which describe the distribution of a solute between the solution and solid phase, of 20 surficial-sediment samples from the INEEL. The K d s for the 20 surficial-sediment samples ranged from 36 to 275 ml/g. Many properties of both the synthesized aqueous solutions and sediments used in the experiments also were determined. Solution properties determined were initial and equilibrium concentrations of calcium, magnesium, and strontium, pH and specific conductance, and initial concentrations of potassium and sodium. Sediment properties determined were grain-size distribution, bulk mineralogy, whole-rock major-oxide and strontium and barium concentrations, and Brunauer-Emmett-Teller (BET) surface area. Solution and sediment properties were correlated with strontium K d s of the 20 surficial sediments using Pearson correlation coefficients. Solution properties with the strongest correlations with strontium K d s were equilibrium pH and equilibrium calcium concentration correlation coefficients, 0.6598 and –0.6518, respectively. Sediment properties with the strongest correlations with strontium K d s were manganese oxide (MnO), BET surface area, and the >4.75-mm-grain-size fraction correlation coefficients, 0.7054, 0.7022, and –0.6660, respectively. Effects of solution properties on strontium K d s were interpreted as being due to competition among similarly charged and sized cations in solution for strontium-sorption sites; effects of sediment properties on strontium K d s were interpreted as being surface-area related. Multivariate analyses of these solution and sediment properties resulted in r 2 values of 0.8071 when all five properties were used and 0.8043 when three properties, equilibrium pH, MnO, and BET surface area, were used.

Idaho↗

Geochemistry and stratigraphic correlation of basalt lavas beneath the Idaho Chemical Processing Plant, Idaho National Engineering Laboratory

Thirty-nine samples of basaltic core were collected from wells 121 and 123, located approximately 1.8 km apart north and south of the Idaho Chemical Processing Plant at the Idaho National Engineering Laboratory. Samples were collected from depths ranging from 15 to 221 m below land surface for the purpose of establishing stratigraphic correlations between these two wells. Elemental analyses indicate that the basalts consist of three principal chemical types. Two of these types are each represented by a single basalt flow in each well. The third chemical type is represented by many basalt flows and includes a broad range of chemical compositions that is distinguished from the other two types. Basalt flows within the third type were identified by hierarchical K-cluster analysis of 14 representative elements: Fe, Ca, K, Na, Sc, Co, La, Ce, Sm, Eu, Yb, Hf, Ta, and Th. Cluster analyses indicate correlations of basalt flows between wells 121 and 123 at depths of approximately 38-40 m, 125-128 m, 131-137 m, 149-158 m, and 183-198 m. Probable correlations also are indicated for at least seven other depth intervals. Basalt flows in several depth intervals do not correlate on the basis of chemical compositions, thus reflecting possible flow margins in the sequence between the wells. Multi-element chemical data provide a useful method for determining stratigraphic correlations of basalt in the upper 1-2 km of the eastern Snake River Plain.

Environmental Geology↗