A novel laboratory simulation system to uncover the mechanisms of uranium upward transport in a desert landscape

Zhang, Qinku; Larson, Steven L.; Ballard, John H.; Cheah, Pohlee; Kazery, Joseph A.; Knotek-Smith, Heather M.; Han, Fengxiang X.

doi:10.1016/j.mex.2019.11.031

Cited by 6 publications

(16 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This upward movement may be caused by the solubility of U in schoepites in soil pore water and was transported driven by high evaporation forces in a desert landscape. 32 Moreover, the corroded products of penetrators from the open field contain silicates in soils. Analyzing U by XRD is also beneficial to determine or explore the chance of other U minerals being produced from penetrators in field soils.…”

Section: ■ Results and Discussionmentioning

confidence: 99%

“…Compared to the UO 2 species, UO 3 and uranyl are more soluble and likely to be found in surface water. , This may explain the appearance of schoepite minerals found in the top surface of the deep buried penetrators in the field through the upward movement of U as uranyl form and redeposited at the surface. This upward movement may be caused by the solubility of U in schoepites in soil pore water and was transported driven by high evaporation forces in a desert landscape . Moreover, the corroded products of penetrators from the open field contain silicates in soils.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Distribution and Fractionation of Uranium in Weapon Tested Range Soils

Kazery

Proctor

Larson

et al. 2021

ACS Earth Space Chem.

Self Cite

View full text Add to dashboard Cite

Uranium is a chemically toxic and radioactive heavy metal. Depleted uranium (DU) is the byproduct of the uranium enrichment process, with a majority of U as uranium-238, and a lower content of the fissile isotope uranium-235 than natural uranium. Uranium-235 is mainly used in nuclear reactors and in the manufacture of nuclear weapons. Exposure is likely to have an impact on humans or the ecosystem where military operations have used DU. Yuma Proving Ground in Arizona, USA has been using depleted uranium ballistics for 36 years. At a contaminated site in the Proving Grounds, soil samples were collected from the flat, open field and lower elevated trenches that typically collect summer runoff. Spatial distribution and fractionation of uranium in the fields were analyzed with total acid digestion and selective sequential dissolution with eight operationally defined solid-phase fractions. In addition to uranium, other trace elements (As, Ba, Co, Cr, Cu, Hg, Mo, Nb, Pd, Pb, V, Zn, Zr) were also assessed. Results show that the trench area in the testing site had a higher accumulation of total U (12.4%) compared to the open-field soil with 279 mg/kg U. Among the eight solid-phase components in the open-field samples, U demonstrated stronger affinities for the amorphous iron-oxide bound, followed by the carbonate bound, and the residual fractions. However, U in the trench area had a stronger binding to the easily reducible oxide bound fraction, followed by the carbonate-bound and amorphous iron-oxide-bound fractions. Among other trace elements, Nb, As, and Zr exhibited the strongest correlations with U distribution among solid-phase components. This study indicates a significant spatial variation of U distribution in the shooting range site. Fe/Mn oxides and carbonate were the major solid-phase components for binding U in the weapon test site.

show abstract

Section: ■ Results and Discussionmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Distribution and Fractionation of Uranium in Weapon Tested Range Soils

Kazery

Proctor

Larson

et al. 2021

ACS Earth Space Chem.

Self Cite

View full text Add to dashboard Cite

show abstract

“…To verify and expand the usefulness of the visualization system in engaging active learning and deeper understanding, an interactive visualization exercise was developed to allow users to study the effect of the type of capillarity solutions (i.e., pore solutions in arid soils) on the speed of the U upward transport. As stated earlier, soil attributes such as the type of capillarity solutions affected capillary action and therefore impacted the speed of U movement in soils [8 , 12] .…”

Section: Methods Detailsmentioning

confidence: 76%

“…With multiple wetting-drying cycles, dissolved U was transported toward the surface and precipitated as yellow-colored uranium oxides [8] . Such a U vertical transport mechanism through alternating wetting and drying conditions has been tested and confirmed under laboratory-controlled conditions [8 , 12] .…”

Section: Introductionmentioning

confidence: 78%