Research Highlights

Research

Hexavalent Uranium Storage Mechanisms In Wet-Dry Cycled Sediments At Contaminated DOE Sites In The Western U.S.

  Noël, V.; Boye, K.; Kukkadapu, R. K.; Li, Q.; Bargar, J. R. Uranium storage mechanisms in wet-dry redox cycled sediments. Water Research.  Water...
November 20, 2020
Process model of each drought cycle
Research

Microbial Communities In Floodplain Soils Remain Unchanged Throughout Seasonal Redox And Water Table Flux

  Fine-grained sediments appear to host distinct microbial groups that are stimulated through water table rise and fall throughout the season The Science Microbial...
August 14, 2020
Spring wet season to summer dry season graph
Research

Diverse Ammonia-Oxidizing Archaea Dominate Subsurface Nitrifying Communities In Semi-Arid Floodplains

  Ammonia oxidation may be driven by archaea rather than bacteria within the riparian subsurface The Science Subsurface microbial communities mediate key biogeochemical transformations...
June 13, 2020
AOA clusters across sites
Research

FeS Nanoclusters Can Mobilize Fe And S From Sediment To The Groundwater

    The Science Nanometer to micrometer sized mineral particles (often associated with organic carbon and often referred to as colloids) that remain suspended...
May 5, 2020
Graph showing the times of sulfidation
Research

Calcium-Uranyl-Carbonato Species Kinetically Limit U(VI) Reduction By Fe(II) And Result In U(V)-Bearing Ferrihydrite

Uranium (U) solubility determines the dissolved concentrations and thus its threat to water quality. It is therefore essential to understand the controls on U...

April 21, 2020
Dissolving calcium-carbonato-U(VI) species
Research

Redox Interfaces Can Produce Toxic Arsenic Levels In Groundwater From Low Arsenic-Abundance Sediments

  Sulfate-rich groundwater promote formation of thioarsenates at fine-coarse sediment interfaces and increases arsenic solubility The Science Groundwater contamination by As from natural and...
February 18, 2020
Sulfate chart of groundwater from oxic to anoxic
Research

Exported Organic Carbon Promotes Reducing Conditions And Redox Cycling In Oxic Aquifers Export Of Carbon From Organic-Enriched Lenses Stimulates...

Aquifers contain abundant organic-enriched, fine-grained, and sulfidic lenses. While it is widely understood that these heterogeneities are important sources of organic carbon, Fe(II), and...

February 18, 2020
Organic-enriched lenses export particulate/colloidal organic C into the surrounding aquifer