Search Results - "Paradis, Charles"

Combining fission-track radiography and scanning electron microscopy to identify uranium host phases by Sultana, Rakiba, Dangelmayr, Martin A., Paradis, Charles J., Johnson, Raymond H.

“…Residual solid-phase uranium from former mill tailings leachate can contribute to persistent concentrations of uranium in groundwater that exceed regulatory…”
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Halophilic bacteria in a Lake Michigan drainage basin as potential biological indicators of chloride-impacted freshwaters by Passante, Elexius K., Dechant, Leah E., Paradis, Charles J., McLellan, Sandra L.

“…There are few biological indicators for freshwater systems subjected to high chloride levels. Freshwater systems receive many forms of chloride such as road…”
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Contaminant mobilization from the vadose zone to groundwater during experimental river flooding events by Sultana, Rakiba, Johnson, Raymond H., Tigar, Aaron D., Wahl, Timothy J., Meurer, Cullen E., Hoss, Kendyl N., Xu, Shangping, Paradis, Charles J.

“…Natural river flooding events can mobilize contaminants from the vadose zone and lead to increased concentrations in groundwater. Characterizing the mass and…”
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Microbial community composition and diversity in Caspian Sea sediments by Mahmoudi, Nagissa, Robeson, Michael S., Castro, Hector F., Fortney, Julian L., Techtmann, Stephen M., Joyner, Dominique C., Paradis, Charles J., Pfiffner, Susan M., Hazen, Terry C.

“…The Caspian Sea is heavily polluted due to industrial and agricultural effluents as well as extraction of oil and gas reserves. Microbial communities can…”
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Push-pull tests for estimating effective porosity: expanded analytical solution and in situ application by Paradis, Charles J., McKay, Larry D., Perfect, Edmund, Istok, Jonathan D., Hazen, Terry C.

“…The analytical solution describing the one-dimensional displacement of the center of mass of a tracer during an injection, drift, and extraction test…”
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Cross-Hole and Vadose-Zone Infiltration Tracer Test Analyses to Determine Aquifer Reactive Transport Parameters at a Former Uranium Mill Site (Grand Junction, Colorado) by Raymond H. Johnson, Ronald D. Kent, Aaron D. Tigar, C. Doc Richardson, Charles J. Paradis, Paul W. Reimus

“…The U.S. Department of Energy Office of Legacy Management is responsible for the long-term care and maintenance of former uranium mill sites in the United…”
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Field experiments of surface water to groundwater recharge to characterize the mobility of uranium and vanadium at a former mill tailing site by Paradis, Charles J., Johnson, Raymond H., Tigar, Aaron D., Sauer, Kirsten B., Marina, Oana C., Reimus, Paul W.

“…Characterizing the mobility of uranium and vanadium in groundwater with a hydraulic connection to surface water is important to inform the best management…”
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Elucidating mobilization mechanisms of uranium during recharge of river water to contaminated groundwater by Paradis, Charles J., Hoss, Kendyl N., Meurer, Cullen E., Hatami, Jiyan L., Dangelmayr, Martin A., Tigar, Aaron D., Johnson, Raymond H.

“…The recharge of stream water below the baseflow water table can mobilize groundwater contaminants, particularly redox-sensitive and sorptive metals such as…”
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Single-Well Push–Pull Tracer Test Analyses to Determine Aquifer Reactive Transport Parameters at a Former Uranium Mill Site (Grand Junction, Colorado) by Raymond H. Johnson, Charles J. Paradis, Ronald D. Kent, Aaron D. Tigar, Paul W. Reimus

“…At a former uranium mill site where tailings have been removed, prior work has determined several potential ongoing secondary uranium sources. These include…”
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Iron‐ and aluminium‐induced depletion of molybdenum in acidic environments impedes the nitrogen cycle by Ge, Xiaoxuan, Vaccaro, Brian J., Thorgersen, Michael P., Poole, Farris L., Majumder, Erica L., Zane, Grant M., De León, Kara B., Lancaster, W. Andrew, Moon, Ji Won, Paradis, Charles J., von Netzer, Frederick, Stahl, David A., Adams, Paul D., Arkin, Adam P., Wall, Judy D., Hazen, Terry C., Adams, Michael W. W.

“…Summary Anthropogenic nitrate contamination is a serious problem in many natural environments. Nitrate removal by microbial action is dependent on the metal…”
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Sustained Ability of a Natural Microbial Community to Remove Nitrate from Groundwater by Paradis, Charles J., Miller, John I., Moon, Ji‐Won, Spencer, Sarah J., Lui, Lauren M., Van Nostrand, Joy D., Ning, Daliang, Steen, Andrew D., McKay, Larry D., Arkin, Adam P., Zhou, Jizhong, Alm, Eric J., Hazen, Terry C.

“…Microbial‐mediated nitrate removal from groundwater is widely recognized as the predominant mechanism for nitrate attenuation in contaminated aquifers and is…”
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Characterization of subsurface media from locations up- and down-gradient of a uranium-contaminated aquifer by Moon, Ji-Won, Paradis, Charles J., Joyner, Dominique C., von Netzer, Frederick, Majumder, Erica L., Dixon, Emma R., Podar, Mircea, Ge, Xiaoxuan, Walian, Peter J., Smith, Heidi J., Wu, Xiaoqin, Zane, Grant M., Walker, Kathleen F., Thorgersen, Michael P., Poole II, Farris L., Lui, Lauren M., Adams, Benjamin G., De León, Kara B., Brewer, Sheridan S., Williams, Daniel E., Lowe, Kenneth A., Rodriguez, Miguel, Mehlhorn, Tonia L., Pfiffner, Susan M., Chakraborty, Romy, Arkin, Adam P., Wall, Judy D., Fields, Matthew W., Adams, Michael W.W., Stahl, David A., Elias, Dwayne A., Hazen, Terry C.

“…The processing of sediment to accurately characterize the spatially-resolved depth profiles of geophysical and geochemical properties along with signatures of…”
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Enhancing Microbial Sulfate Reduction of Hydrocarbons in Groundwater Using Permeable Filled Borings by Buscheck, Timothy, Mackay, Douglas, Paradis, Charles, Schmidt, Radomir, Sieyes, Nicholas

“…At a service station closed in 1993, groundwater contained benzene that persisted above the cleanup goal of 1 mg/L in zones depleted of background sulfate. The…”
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In situ mobility of uranium in the presence of nitrate following sulfate-reducing conditions by Paradis, Charles J., Jagadamma, Sindhu, Watson, David B., McKay, Larry D., Hazen, Terry C., Park, Melora, Istok, Jonathan D.

“…Reoxidation and mobilization of previously reduced and immobilized uranium by dissolved-phase oxidants poses a significant challenge for remediating…”
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Correction: Push-pull tests for estimating effective porosity: expanded analytical solution and in situ application by Paradis, Charles J., McKay, Larry D., Perfect, Edmund, Istok, Jonathan D., Hazen, Terry C.

“…In the recent article by Paradis et al. (2018), an error was made when developing a conceptual model and an analytical solution to describe the one-dimensional…”
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Improved Method for Estimating Reaction Rates During Push‐Pull Tests by Paradis, Charles J., Dixon, Emma R., Lui, Lauren M., Arkin, Adam P., Parker, Jack C., Istok, Jonathan D., Perfect, Edmund, McKay, Larry D., Hazen, Terry C.

“…The breakthrough curve obtained from a single‐well push‐pull test can be adjusted to account for dilution of the injection fluid in the aquifer fluid. The…”
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In situ decay of polyfluorinated benzoic acids under anaerobic conditions by Paradis, Charles J., Moon, Ji-Won, Elias, Dwayne A., McKay, Larry D., Hazen, Terry C.

“…Polyfluorinated benzoic acids (PBAs) can be used as non-reactive tracers to characterize reactive mass transport mechanisms in groundwater. The use of PBAs as…”
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Desorption and Co‐Dissolution of Uranium‐Bearing Solids During Alkalinity‐Enhanced Flushing of Contaminated Sediments by Dangelmayr, Martin, Meurer, Cullen, Tigar, Aaron, Johnson, Raymond H., Paradis, Charles

“…Elevated uranium concentrations in groundwater remain a persistent challenge at contaminated sites. Several sites rely on natural flushing of uranium as a…”
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Desorption and Co‐Dissolution of Uranium‐Bearing Solids During Alkalinity‐Enhanced Flushing of Contaminated Sediments by Dangelmayr, Martin, Meurer, Cullen, Tigar, Aaron, Johnson, Raymond H., Paradis, Charles

“…Abstract Elevated uranium concentrations in groundwater remain a persistent challenge at contaminated sites. Several sites rely on natural flushing of uranium…”
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Single‐Well Injection‐Drift Test to Estimate Groundwater Velocity by Paradis, Charles, Van Ee, Nathan, Hoss, Kendyl, Meurer, Cullen, Tigar, Aaron, Reimus, Paul, Johnson, Raymond

“…A simple algebraic equation is presented here to estimate the magnitude of groundwater velocity based on data from a single‐well injection‐drift test thereby…”
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