Nikolla Qafoku

Assessing the selective bioweathering of minerals by fungi in soil ecosystems

Lead Institution

University of California, Davis

Principal Investigator

Rebecca Lybrand

Project type

Large-Scale EMSL Research

Rock weathering replenishes nutrients in soil, shapes geochemical carbon sequestration, and drives physical, chemical, and biological processes at a multitude of scales. Globally, lithology type and…

Soil mineralogy control on SOC stability in soils

Lead Institution

United States Department of Agriculture - Agricultural Research Service

Principal Investigator

Zamir Libohova

Project type

MONet

Soil Organic Carbon (SOC) pools and stability are influenced by interactions between climate, management, and soil properties. Numerous studies have determined the size and stability of SOC pools by…

Investigating spatiotemporal monitoring of soil organic matter using spectral induced polarization

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

Judith Robinson

Understanding soil organic matter (SOM) dynamic behavior and interactions is critical in determining regional soil fertility and health. SOM controls crop yields, the diversity of microorganisms used…

Molecular-Scale Assessment of Technetium and Iodine Phase Chemistry in Fluidized Bed Steam Reformer Waste Form

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

James Amonette

Project type

Large-Scale EMSL Research

Technetium (99Tc) and radioactive iodine (129I) are long-lived fission products found in nuclear waste. Their abundance coupled with their long half-lives and aqueous mobility, make them the two…

Influence of Adsorbed Organic Acids on Soil Mineral Wettability

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

John Loring

Project type

Large-Scale EMSL Research

Soil wettability is dictated by the extent to which hydrophilic mineral surfaces are covered by hydrophobic soil organic carbon (SOC) from bacterial decomposition, decaying plant matter, or root…

Phase Chemistry in Fluidized-Bed Steam Reformer Waste-Form Granules Containing Technetium and Iodine

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

James Amonette

Project type

Limited Scope

Technetium (99Tc) and radioactive iodine (129I) are long-lived fission products found in nuclear waste. Their abundance coupled with their long half-lives and aqueous mobility, make them the two…

3D pore-scale characterization of soil cores in EMSL: Imaging - Pore Network Analysis - Flow and Transport Properties workflow

Lead Institution

Environmental Molecular Sciences Laboratory

Principal Investigator

Tamas Varga

As part of a larger effort to establish a soil characterization capability that will make EMSL a one-stop shop for high-throughput characterization of soil microstructure, flow and transport…

Remediation & Closure Science Project/ Subsurface Science Tasks (Zachara/Freshly, EM-closure, PNNL Scope #47040). [was aka S & T Road Mapping for Needs From All Sources (PNNL Scope #30998)].

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

John Zachara

Project type

Exploratory Research

Hanford Remediation and Closure Science Project The Hanford Site Groundwater Protection Program, formerly the Groundwater/ Vadose Zone Integration Project, was established in 1997 to develop the…

Influence of soil porous microstructure on the distribution and transport of SOM

Lead Institution

Environmental Molecular Sciences Laboratory

Principal Investigator

Tamas Varga

There is a need to better understand the relationship between soil pore structure and the fate and transport of soil organic matter (SOM) to improve process-based predictions of OM accessibility…

Non-enzymatic interactions between U(VI) and biogenic mackinawite

Lead Institution

Virginia Polytechnic Institute

Principal Investigator

Harish Veeramani

Project type

Limited Scope

Reduction of subsurface contaminant uranium to a sparingly soluble mineral; uraninite (UO2) is being extensively researched as a remediation strategy for mitigating uranium contamination in-situ. The…

Fe Oxide Waste Form for Tc Immobilization

Lead Institution

Pohang University of Science & Technology

Principal Investigator

Wooyong Um

The objective of this work is to develop a waste form that will sequester Tc in a Goethite matrix that will be resistant to Tc-leaching. Goethite (?-FeOOH) is a low-temperature secondary weathering…

Uranium sequestration and release by framboidal pyrite in bioreduced sediments

Lead Institution

Virginia Polytechnic Institute

Principal Investigator

Harish Veeramani

Project type

Large-Scale EMSL Research

Exploratory research is proposed to gain insight into interactions between microbes, framboidal pyrite (FeS2), and uranium (U) in organic-matter rich, naturally bioreduced zones at an Integrated…

Understanding molecular-scale complexity and interactions of soil organic matter

Lead Institution

Environmental Molecular Sciences Laboratory

Principal Investigator

Amity Andersen

The goal of this proposal is to focus on the fundamental molecular-level (nanometer) structure and interactions of soil organic matter (SOM) using well-established approaches that provide…

Liquid and environmental TEM as transformative capabilities in carbon cycle research

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

James De Yoreo

Project type

Special Science

The purpose of this research is to develop a quantitative picture of the impact of increasing global temperatures on organic-soil mineral interactions within the context of both microbial control…

Immobilization of radionuclides in the Hanford vadose zone by incorporation in solid phase

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

Nikolla Qafoku

Project type

Exploratory Research

The objective of the project are: 1. to investigate the effect of aging on the stability of sorption complexes on Al oxyhydroxides surfaces formed from neutralization and homogeneous nucleation of…

Understanding the Effects of the Addition of Supplemental Inorganic Sequestering Materials to Inhibit the Release of Radionuclides from Cementitious Waste Forms with Nuclear Magnetic Resonance Spectroscopy

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

Nikolla Qafoku

Immobilization in cementitious materials is a commonly employed method of remediation of low- and intermediate-level radioactive and hazardous species around the world. Indeed, the baseline method of…

Contaminant-Organic Complexes: Their Structure and Energetics in Surface Decontamination Processes

Lead Institution

University of California, Merced

Principal Investigator

Samuel Traina

Project type

Exploratory Research

The objective of this project is to measure the decay rate constants for the europium species in solid samples.The solid samples to be analyzed contain gibbsite, europium and siderophore (DFB).The…

In situ characterization of soil organic carbon-mineral interactions for carbon cycle research

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

James De Yoreo

The purpose of this research is to develop a quantitative picture of the impact of increasing global temperatures on organic-soil mineral interactions within the context of both microbial control…

Dissolution and precipitation in the Hanford sediments under hyperalkaline conditions

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

Nikolla Qafoku

Project type

Exploratory Research

Hanford sediments were treated with Al-rich, hyperalkaline and saline solution. As a result, dissolution ocurred and Si, Fe, K, Al, Mn, Mg, Ca, Ba were released into the soil solution. …

Understanding the Effects of the Addition of Supplemental Inorganic Sequestering Materials to Inhibit the Release of Radionuclides from Cementitious Waste Forms with Nuclear Magnetic Resonance Spectroscopy

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

Nikolla Qafoku

Immobilization in cementitious materials is a commonly employed method of remediation of low- and intermediate-level radioactive and hazardous species around the world. Indeed, the baseline method of…

solid phase transformations in the Hanford sediments treated with Al-rich, hyperalkaline and saline
solutions

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

Nikolla Qafoku

Project type

Exploratory Research

Uncontaminated Hanford sediments were treated with Al-rich, hyperalkaline and saline solution under O2 free conditions. The objective was to study the solid phase transformation, i.e., dissolution…

Advancing ecosystem understanding of carbon turnover and storage through molecular characterization

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

Kirsten Hofmockel

The coupling between concurrently changing carbon (C) and nitrogen (N) cycles remains a key uncertainty in understanding feedbacks between the terrestrial C cycle and climate change. Decades of…

57Fe-Mossbauer studies of sediment cores from Integrated Field-Scale Subsurface Research Challenge Site at Rifle, Colorado

Lead Institution

Environmental Molecular Sciences Laboratory

Principal Investigator

Ravi Kukkadapu

The U.S. DOE faces the challenge of cleaning up and/or monitoring large, dilute plumes contaminated by metals, such as U, Tc, Pu, Hg, Cr, etc, whose mobility and solubility change with aquifer redox…

Immobilization and interactions of Tc and I in the subsurface and mechanisms controlling their retention

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

Nikolla Qafoku

The vadose zone at the Hanford site represents a continuous source of radioactive and other contaminants to groundwater through flux created by recharge from precipitation. This project will…

The chemistry and mineralogy of variable charge soils

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

Nikolla Qafoku

Project type

Exploratory Research

I received an invitation to write a review paper (chapter) for the Journal: Advances in Agronomy, which is a well established and highly regarded serial publication (ranked #1 in Agriculture). In…

Advancing ecosystem understanding of carbon turnover and storage through molecular characterization

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

Kirsten Hofmockel

EMSL Staff Proposal: The coupling between concurrently changing carbon (C) and nitrogen (N) cycles remains a key uncertainty in understanding feedbacks between the terrestrial C cycle and climate…

A Waste Form Based Upon Goethite [alpha-Fe(III) O . OH] and Strengite [Fe(III)PO4 . 2H2O]

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

R. Serne

Project type

Large-Scale EMSL Research

The objective of this research effort is the development of a waste form that will sequester Tc and I in a matrix that will be resistant to leaching. Goethite (alpha-Fe(III)O . OH) is a low…

Integrating thermodynamic and microbial mechanisms to understand coupled controls of carbon and nitrogen on hyporheic zone metabolism

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

James Stegen

Project type

Large-Scale EMSL Research

Terrestrial-aquatic interfaces are widely recognized as active zones of organic matter metabolism, and hyporheic zones in particular are critical in determining the fate of organic matter globally…

57Fe-Mossbauer studies of sediment cores from Integrated Field-Scale Subsurface Research Challenge Site at Rifle, Colorado

Lead Institution

Environmental Molecular Sciences Laboratory

Principal Investigator

Ravi Kukkadapu

The U.S. DOE faces the challenge of cleaning up and/or monitoring large, dilute plumes contaminated by metals, such as U, Tc, Pu, Hg, Cr, etc, whose mobility and solubility change with aquifer redox…

Reactivity of Soil Organic Carbon with Minerals under Low Water Conditions

Lead Institution

Pacific Northwest National Laboratory

Principal Investigator

John Loring

Project type

Exploratory Research

The manner in which soil organic carbon (SOC) binds to and reacts with mineral surfaces affects SOC (bio)degradation, SOC mobility, soil wettability, mineral dissolution, and the bioavailability of…

Projects