Spatially Resolved U(VI) Partitioning and Speciation: Implications for Plume Scale Behavior of Contaminant U in the Hanford Vadose Zone

Hanford Site Vadose Zone Studies: An Overview

899 The Hanford Site is 1517 km2 (586 mi2) in size, located in a sparsely populated area in the rain shadow of the Cascade Mountains, adjacent to the Columbia River in southeastern Washington State (Fig. 1). The Hanford Site was set aside in the early 1940s by the U.S. Government to perform a top-secret mission, the Manhattan Project, for production of plutonium for atomic weapons used to end W...

Cryogenic laser induced fluorescence characterization of U(VI) in Hanford Vadose Zone pore waters.

Ambient and liquid helium temperature laser-induced time-resolved uranyl fluorescence spectroscopy was applied to study the speciation of aqueous uranyl solutions containing carbonate and phosphate and two porewater samples obtained by ultracentrifugation of U(VI)-contaminated sediments. The significantly enhanced fluorescence signal intensity and spectral resolution found at liquid helium temp...

Spectroscopic and diffraction study of uranium speciation in contaminated vadose zone sediments from the Hanford site, Washington state.

Contamination of vadose zone sediments under tank BX-102 at the Hanford site, Washington, resulted from the accidental release of 7-8 metric tons of uranium dissolved in caustic aqueous sludge in 1951. We have applied synchrotron-based X-ray spectroscopic and diffraction techniques to characterize the speciation of uranium in samples of these contaminated sediments. UIII-edge X-ray absorption f...

Geochemical Controls on Contaminant Uraniumin Vadose Hanford Formation Sediments at the 200Area and 300 Area, Hanford Site, Washington

Spectroscopic evidence for uranium bearing precipitates in vadose zone sediments at the Hanford 300-area site.

Uranium (U) solid-state speciation in vadose zone sediments collected beneath the former North Process Pond (NPP) in the 300 Area of the Hanford site (Washington) was investigated using multi-scale techniques. In 30 day batch experiments, only a small fraction of total U (approximately 7.4%) was released to artificial groundwater solutions equilibrated with 1% pCO2. Synchrotron-based micro-X-ra...