A5055782825- Soil and Water Nutrient Dynamics
- Microbial bioremediation and biosurfactants
- Atmospheric and Environmental Gas Dynamics
- Fish Ecology and Management Studies
- Water Quality and Pollution Assessment
- Toxic Organic Pollutants Impact
- Groundwater flow and contamination studies
- Hydraulic Fracturing and Reservoir Analysis
- Water Quality Monitoring Technologies
- Water Treatment and Disinfection
- Water Quality Monitoring and Analysis
- Hydrology and Watershed Management Studies
- Wastewater Treatment and Nitrogen Removal
- Water Quality and Resources Studies
- Extraction and Separation Processes
- Anaerobic Digestion and Biogas Production
- Marine and coastal ecosystems
- Water Systems and Optimization
- Constructed Wetlands for Wastewater Treatment
- Groundwater and Isotope Geochemistry
- Environmental Chemistry and Analysis
- Isotope Analysis in Ecology
- Membrane Separation Technologies
- Radioactive element chemistry and processing
- Odor and Emission Control Technologies
Lawrence Berkeley National Laboratory
2016-2025
University of the Pacific
2009-2025
Stockton University
2018
Energy Biosciences Institute
2014
NASA Earth Science
2008-2012
Southern California Coastal Water Research Project
2009
Stanford University
2009
United States Geological Survey
2009
University of California, Santa Cruz
2009
University of California, Berkeley
1999-2001
The biological effects and expected fate of the vast amount oil in Gulf Mexico from Deepwater Horizon blowout are unknown owing to depth magnitude this event. Here, we report that dispersed hydrocarbon plume stimulated deep-sea indigenous γ-Proteobacteria closely related known petroleum degraders. Hydrocarbon-degrading genes coincided with concentration various contaminants. Changes composition distance source incubation experiments environmental isolates demonstrated faster-than-expected...
Abstract The Deepwater Horizon (DWH) oil spill in the spring of 2010 resulted an input ∼4.1 million barrels to Gulf Mexico; >22% this is unaccounted for, with unknown environmental consequences. Here we investigated impact deposition on microbial communities surface sediments collected at 64 sites by targeted sequencing 16S rRNA genes, shotgun metagenomic 14 these samples and mineralization experiments using 14C-labeled model substrates. gene data indicated that most heavily...
The Deepwater Horizon oil spill produced large subsurface plumes of dispersed and gas in the Gulf Mexico that stimulated growth psychrophilic, hydrocarbon degrading bacteria. We tracked succession plume bacteria before, during after 83-day to determine microbial response biodegradation potential throughout incident. Dominant shifted substantially over time were dependent on relative quantities different fractions. Unmitigated flow from wellhead early resulted highest proportions n-alkanes...
Lithium is the principal component of high-energy-density batteries and a critical material necessary for economy security United States. Brines from geothermal power production have been identified as potential domestic source lithium; however, lithium-rich brines are characterized by complex chemistry, high salinity, temperatures, which pose unique challenges economic lithium extraction. The purpose this paper to examine analyze direct extraction technology in context developing...
Polynuclear aromatic hydrocarbons (PAHs) typically exist as complex mixtures in contaminated soils, yet little is known about the biodegradation of PAHs mixtures. We have isolated two physiologically diverse bacteria, Pseudomonas stutzeri P-16 and P. saccharophila P-15, from a creosote-contaminated soil by enrichment on phenanthrene sole carbon source studied their ability to metabolize several other two- three-ring PAHs. Naphthalene, 1-methylnaphthalene, 2-methylnaphthalene served growth...
Mineral scale formation on membrane surfaces is a significant challenge in reverse osmosis water purification. Laboratory fouling experiments are typically run such that the transmembrane pressure (TMP) fixed, and permeate flux decreases over time as scales accumulate surface. However, this change means hydrodynamic conditions at surface continuously changing, which could affect crystallization foulant deposition processes. Operating under constant conditions, contrast, advantageous because...
Ten bacterial strains were isolated from seven contaminated soils by enrichment with phenanthrene as the sole carbon source. These isolates and another phenanthrene-degrading strain examined for various characteristics related to degradation their ability metabolize 12 other polycyclic aromatic hydrocarbons (PAH), ranging in size two five rings, after growth presence of phenanthrene. Fatty acid methyl ester analysis indicated that at least genera (Agrobacterium, Bacillus, Burkholderia,...
The low water solubility of polycyclic aromatic hydrocarbons is believed to limit their availability microorganisms, which a potential problem for bioremediation hydrocarbon-contaminated sites. Surfactants have been suggested enhance the bioavailability hydrophobic compounds, but both negative and positive effects surfactants on biodegradation reported in literature. Earlier, we presented mechanistic models phenanthrene dissolution kinetics solubilized surfactant micelles. In this study,...
The oxygen isotopic composition of dissolved inorganic phosphate (δ18Op) in many aquatic ecosystems is not equilibrium with ambient water and, therefore, may reflect the source δ18Op. Identification sources to bodies critical for designing best management practices load reduction control eutrophication. In order δ18Op be a useful tool tracking, must distinguishable from one another; however, potential has been well characterized. We measured variety known sources, including fertilizers,...
Abstract Saline brines currently being brought to the surface produce geothermal energy in Salton Sea region of California contain high concentrations lithium that could potentially be extracted before brine is reinjected back into reservoir. This would create a new supply chain domestically sourced for United States lithium-based batteries will help drive transition renewable-based grid. Plans expand production along with extraction are considered known resource area. We discuss water...
Two species of bacteria, identified as Pseudomonas stutzeri (P-16) and saccharophila (P-15) by fatty acid methyl ester analysis, were found in a phenanthrene enrichment culture creosote-contaminated soil. The organisms are shown to be physiologically dissimilar, their genetic relatedness is discussed. Phenanthrene degradation both followed Michaelis–Menten kinetics, allowing for the determination half-saturation (K s ) maximum activity coefficients, using nonlinear regression. Both utilized...
A fundamental knowledge of microbial community structure in petroleum reservoirs can improve predictive modeling these environments. We used hydrocarbon profiles, stable isotopes, and high-density DNA microarray analysis to characterize communities produced water from four Alaskan North Slope reservoirs. Produced fluids Schrader Bluff (24-27°C), Kuparuk (47-70°C), Sag River (80°C), Ivishak (80-83°C) were collected, with paired soured/non-soured wells sampled Ivishak. Chemical isotope data...
Direct lithium extraction (DLE) of brines after geothermal power production offers opportunities to produce environmentally benign “green” lithium; however, some environmental impact is inevitable. We examined solid waste at plants in southern California that are also locations for planned DLE facilities. Currently, the this region approximately 79,800 metric tons (wet weight) per year waste, which represents about 28 GWh net electricity or 500 mg solids kg brine. Approximately 15% requires...