Search Results - "Wilkin, Richard T"

Solution equilibria of uranyl minerals: Role of the common groundwater ions calcium and carbonate by Stanley, Dovie M., Wilkin, Richard T.

“…[Display omitted] •Metaschoepite yields low U(VI) concentrations in CO2-poor groundwater at near-neutral pH.•Uranophane produces low U(VI) concentrations at…”
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Geochemical Impacts to Groundwater from Geologic Carbon Sequestration: Controls on pH and Inorganic Carbon Concentrations from Reaction Path and Kinetic Modeling by Wilkin, Richard T, DiGiulio, Dominic C

“…Geologic carbon sequestration has the potential to cause long-term reductions in global emissions of carbon dioxide to the atmosphere. Safe and effective…”
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Cadmium in soils and groundwater: A review by Kubier, Andreas, Wilkin, Richard T., Pichler, Thomas

“…Cadmium (Cd) is a non-essential trace element that is widely distributed in the environment. Both geogenic and anthropogenic sources can elevate Cd…”
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Impact of iron sulfide transformation on trichloroethylene degradation by He, Y. Thomas, Wilson, John T., Wilkin, Richard T.

“…Trichloroethylene (TCE) is one of the most common and persistent groundwater contaminants encountered at hazardous waste sites around the world. A growing body…”
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Complexities in attributing lead contamination to specific sources in an industrial area of Philadelphia, PA by Tuccillo, Mary Ellen, Blue, Julie, Koplos, Jonathan, Kelly, Jack, Wilkin, Richard T.

“…Globally, lead (Pb) contamination is one of the top ten chemical exposure issues affecting public health. The identification of specific Pb sources provides…”
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Removal of Arsenate and Arsenite in Equimolar Ferrous and Ferric Sulfate Solutions through Mineral Coprecipitation: Formation of Sulfate Green Rust, Goethite, and Lepidocrocite by Su, Chunming, Wilkin, Richard T

“…An improved understanding of in situ mineralization in the presence of dissolved arsenic and both ferrous and ferric iron is necessary because it is an…”
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Perchlorate Behavior in a Municipal Lake Following Fireworks Displays by Wilkin, Richard T, Fine, Dennis D, Burnett, Nicole G

“…Perchlorate salts of potassium and ammonium are the primary oxidants in pyrotechnic mixtures, yet insufficient information is available regarding the…”
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Formation of Ferrihydrite and Associated Iron Corrosion Products in Permeable Reactive Barriers of Zero-Valent Iron by Furukawa, Yoko, Kim, Jin-wook, Watkins, Janet, Wilkin, Richard T

“…Ferrihydrite, which is known to form in the presence of oxygen and to be stabilized by the adsorption of Si, PO4 and SO4, is ubiquitous in the fine-grained…”
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In Situ Chemical Reduction of Cr(VI) in Groundwater Using a Combination of Ferrous Sulfate and Sodium Dithionite:  A Field Investigation by Ludwig, Ralph D, Su, Chunming, Lee, Tony R, Wilkin, Richard T, Acree, Steven D, Ross, Randall R, Keeley, Ann

“…A field study was conducted to evaluate the performance of a ferrous iron based in situ redox zone for the treatment of a dissolved phase Cr(VI) plume at a…”
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Treatment of Arsenic, Heavy Metals, and Acidity Using a Mixed ZVI-Compost PRB by Ludwig, Ralph D, Smyth, David J. A, Blowes, David W, Spink, Laura E, Wilkin, Richard T, Jewett, David G, Weisener, Christopher J

“…A 30-month performance evaluation of a pilot permeable reactive barrier (PRB) consisting of a mixture of leaf compost, zero-valent iron (ZVI), limestone, and…”
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Laboratory evaluation of zero-valent iron to treat water impacted by acid mine drainage by Wilkin, Richard T., McNeil, Mary S.

“…This study examines the applicability and limitations of granular zero-valent iron for the treatment of water impacted by mine wastes. Rates of…”
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Uptake of nickel by synthetic mackinawite by Wilkin, Richard T., Beak, Douglas G.

“…The uptake of aqueous Ni(II) by synthetic mackinawite (FeS) was examined in anaerobic batch experiments at near-neutral pH (5.2 to 8.4). Initial molar ratios…”
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Performance of a zerovalent iron reactive barrier for the treatment of arsenic in groundwater: Part 1. Hydrogeochemical studies by Wilkin, Richard T., Acree, Steven D., Ross, Randall R., Beak, Douglas G., Lee, Tony R.

“…Developments and improvements of remedial technologies are needed to effectively manage arsenic contamination in groundwater at hazardous waste sites. In June…”
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Potential aquifer vulnerability in regions down-gradient from uranium in situ recovery (ISR) sites by Saunders, James A., Pivetz, Bruce E., Voorhies, Nathan, Wilkin, Richard T.

“…Sandstone-hosted roll-front uranium ore deposits originate when U(VI) dissolved in groundwater is reduced and precipitated as insoluble U(IV) minerals…”
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Microbial sulfate reduction and metal attenuation in pH 4 acid mine water by Church, Clinton D, Wilkin, Richard T, Alpers, Charles N, Rye, Robert O, McCleskey, R Blaine

“…Sediments recovered from the flooded mine workings of the Penn Mine, a Cu-Zn mine abandoned since the early 1960s, were cultured for anaerobic bacteria over a…”
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Evidence of Sulfate-Dependent Anaerobic Methane Oxidation within an Area Impacted by Coalbed Methane-Related Gas Migration by Wolfe, Amy L, Wilkin, Richard T

“…We evaluated water quality characteristics in the northern Raton Basin of Colorado and documented the response of the Poison Canyon aquifer system several…”
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Fifteen-year assessment of a permeable reactive barrier for treatment of chromate and trichloroethylene in groundwater by Wilkin, Richard T., Acree, Steven D., Ross, Randall R., Puls, Robert W., Lee, Tony R., Woods, Leilani L.

“…The fifteen-year performance of a granular iron, permeable reactive barrier (PRB; Elizabeth City, North Carolina) is reviewed with respect to contaminant…”
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Mechanisms of water-rock interaction and implications for remediating flooded mine workings elucidated from environmental tracers, stable isotopes, and rare earth elements by Newman, Connor P., Walton-Day, Katherine, Runkel, Robert L., Wilkin, Richard T.

“…Contamination from acid mine drainage affects ecosystems and usability of groundwater for domestic and municipal purposes. The Captain Jack Superfund Site…”
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Rare-Earth Elements as Natural Tracers for In Situ Remediation of Groundwater by Wilkin, Richard T, Lee, Tony R, Ludwig, Ralph D, Wadler, Claire, Brandon, William, Mueller, Brian, Davis, Eva, Luce, Darryl, Edwards, Tracy

“…The utility of rare-earth elements (REEs) as natural geochemical tracers for the analysis of groundwater remediation was examined in several example permeable…”
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Geochemical and Isotope Study of Trichloroethene Degradation in a Zero-Valent Iron Permeable Reactive Barrier: A Twenty-Two-Year Performance Evaluation by Wilkin, Richard T, Lee, Tony R, Sexton, Molly R, Acree, Steven D, Puls, Robert W, Blowes, David W, Kalinowski, Christopher, Tilton, Jennifer M, Woods, Leilani L

“…This study provides a twenty-two-year record of in situ degradation of chlorinated organic compounds by a granular iron permeable reactive barrier (PRB)…”
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