Reactive solute transport models are useful tools for analyzing complex geochemical behavior resulting from biodegradation of organic compounds by multiple terminal electron acceptors (TEAPs). The usual approach of simulating the reactions of multiple TEAPs by an irreversible Monod rate law was compared with simulations that assumed a partial local equilibrium or kinetically controlled reactions subject to the requirement that the Gibbs free energy of reaction (Δ G) was either less than zero or less than a threshold value. Simulations were performed using a single organic substrate and O2, FeOOH, SO4-2 and CO2 as the terminal electron acceptors. It was assumed that the organic substrate was slowly and completely fermented to CO2 and H2 and the H2 was oxidized by the TEAPs. Simulations using the Monod approach showed that this irreversible rate law forced the reduction of both FeOOH and CO2 to proceed even when Δ G was positive. This resulted in an over prediction in amount of FeOOH reduced to Fe(II) in parts of the domain and it resulted in large errors in pH. Simulations using mass action kinetics agreed with equilibrium simulations for the case of large rate constants. The extent of reductive dissolution of FeOOH was strongly dependent on the thermodynamic stability of the FeOOH phase. Transport simulations performed assuming that the reactions of the TEAPs stopped when Δ G exceeded a threshold value showed that only simulated H2 concentrations were affected if the threshold value was the same for each TEAP. Simulated H2 concentrations were controlled by the fastest reaction of the TEAP, but it was common for reactions to occur concomitantly rather than sequentially.
","language":"English","publisher":"Elsevier","doi":"10.1016/S0098-3004(03)00008-6","issn":"00983004","usgsCitation":"Curtis, G.P., 2003, Comparison of approaches for simulating reactive solute transport involving organic degradation reactions by multiple terminal electron acceptors: Computers & Geosciences, v. 29, no. 3, p. 319-329, https://doi.org/10.1016/S0098-3004(03)00008-6.","productDescription":"11 p.","startPage":"319","endPage":"329","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":234817,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":208808,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0098-3004(03)00008-6"}],"volume":"29","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059f84fe4b0c8380cd4cff6","contributors":{"authors":[{"text":"Curtis, Gary P. 0000-0003-3975-8882 gpcurtis@usgs.gov","orcid":"https://orcid.org/0000-0003-3975-8882","contributorId":2346,"corporation":false,"usgs":true,"family":"Curtis","given":"Gary","email":"gpcurtis@usgs.gov","middleInitial":"P.","affiliations":[{"id":438,"text":"National Research Program - Western Branch","active":true,"usgs":true}],"preferred":true,"id":406296,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70025674,"text":"70025674 - 2003 - Estimation of past seepage volumes from calcite distribution in the Topopah Spring Tuff, Yucca Mountain, Nevada","interactions":[],"lastModifiedDate":"2012-03-12T17:20:22","indexId":"70025674","displayToPublicDate":"2003-01-01T00:00:00","publicationYear":"2003","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2233,"text":"Journal of Contaminant Hydrology","active":true,"publicationSubtype":{"id":10}},"title":"Estimation of past seepage volumes from calcite distribution in the Topopah Spring Tuff, Yucca Mountain, Nevada","docAbstract":"Low-temperature calcite and opal record the past seepage of water into open fractures and lithophysal cavities in the unsaturated zone at Yucca Mountain, Nevada, site of a proposed high-level radioactive waste repository. Systematic measurements of calcite and opal coatings in the Exploratory Studies Facility (ESF) tunnel at the proposed repository horizon are used to estimate the volume of calcite at each site of calcite and/or opal deposition. By estimating the volume of water required to precipitate the measured volumes of calcite in the unsaturated zone, seepage rates of 0.005 to 5 liters/year (l/year) are calculated at the median and 95th percentile of the measured volumes, respectively. These seepage rates are at the low end of the range of seepage rates from recent performance assessment (PA) calculations, confirming the conservative nature of the performance assessment. However, the distribution of the calcite and opal coatings indicate that a much larger fraction of the potential waste packages would be contacted by this seepage than is calculated in the performance assessment.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Contaminant Hydrology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0169-7722(02)00167-5","issn":"01697722","usgsCitation":"Marshall, B., Neymark, L., and Peterman, Z.E., 2003, Estimation of past seepage volumes from calcite distribution in the Topopah Spring Tuff, Yucca Mountain, Nevada: Journal of Contaminant Hydrology, v. 62-63, p. 237-247, https://doi.org/10.1016/S0169-7722(02)00167-5.","startPage":"237","endPage":"247","numberOfPages":"11","costCenters":[],"links":[{"id":208739,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0169-7722(02)00167-5"},{"id":234705,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"62-63","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a0b9de4b0c8380cd527d4","contributors":{"authors":[{"text":"Marshall, B.D.","contributorId":19581,"corporation":false,"usgs":true,"family":"Marshall","given":"B.D.","email":"","affiliations":[],"preferred":false,"id":406121,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Neymark, L.A. 0000-0003-4190-0278","orcid":"https://orcid.org/0000-0003-4190-0278","contributorId":56673,"corporation":false,"usgs":true,"family":"Neymark","given":"L.A.","affiliations":[],"preferred":false,"id":406122,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Peterman, Z. E.","contributorId":63781,"corporation":false,"usgs":true,"family":"Peterman","given":"Z.","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":406123,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70025671,"text":"70025671 - 2003 - Chlorine-36 data at Yucca Mountain: Statistical tests of conceptual models for unsaturated-zone flow","interactions":[],"lastModifiedDate":"2012-03-12T17:20:22","indexId":"70025671","displayToPublicDate":"2003-01-01T00:00:00","publicationYear":"2003","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2233,"text":"Journal of Contaminant Hydrology","active":true,"publicationSubtype":{"id":10}},"title":"Chlorine-36 data at Yucca Mountain: Statistical tests of conceptual models for unsaturated-zone flow","docAbstract":"An extensive set of chlorine-36 (36Cl) data has been collected in the Exploratory Studies Facility (ESF), an 8-km-long tunnel at Yucca Mountain, Nevada, for the purpose of developing and testing conceptual models of flow and transport in the unsaturated zone (UZ) at this site. At several locations, the measured values of 36Cl/Cl ratios for salts leached from rock samples are high enough to provide strong evidence that at least a small component of bomb-pulse 36Cl, fallout from atmospheric testing of nuclear devices in the 1950s and 1960s, was measured, implying that some fraction of the water traveled from the ground surface through 200-300 m of unsaturated rock to the level of the ESF during the last 50 years. These data are analyzed here using a formal statistical approach based on log-linear models to evaluate alternative conceptual models for the distribution of such fast flow paths. The most significant determinant of the presence of bomb-pulse 36Cl in a sample from the welded Topopah Spring unit (TSw) is the structural setting from which the sample was collected. Our analysis generally supports the conceptual model that a fault that cuts through the nonwelded Paintbrush tuff unit (PTn) that overlies the TSw is required in order for bomb-pulse 36Cl to be transmitted to the sample depth in less than 50 years. Away from PTn-cutting faults, the ages of water samples at the ESF appear to be a strong function of the thickness of the nonwelded tuff between the ground surface and the ESF, due to slow matrix flow in that unit. ?? 2002 Elsevier Science B.V. All rights reserved.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Contaminant Hydrology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0169-7722(02)00176-6","issn":"01697722","usgsCitation":"Campbell, K., Wolfsberg, A., Fabryka-Martin, J., and Sweetkind, D., 2003, Chlorine-36 data at Yucca Mountain: Statistical tests of conceptual models for unsaturated-zone flow: Journal of Contaminant Hydrology, v. 62-63, p. 43-61, https://doi.org/10.1016/S0169-7722(02)00176-6.","startPage":"43","endPage":"61","numberOfPages":"19","costCenters":[],"links":[{"id":208716,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0169-7722(02)00176-6"},{"id":234669,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"62-63","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059f5cde4b0c8380cd4c423","contributors":{"authors":[{"text":"Campbell, K.","contributorId":10526,"corporation":false,"usgs":true,"family":"Campbell","given":"K.","affiliations":[],"preferred":false,"id":406111,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Wolfsberg, A.","contributorId":106291,"corporation":false,"usgs":true,"family":"Wolfsberg","given":"A.","affiliations":[],"preferred":false,"id":406114,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Fabryka-Martin, J.","contributorId":51467,"corporation":false,"usgs":true,"family":"Fabryka-Martin","given":"J.","affiliations":[],"preferred":false,"id":406112,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Sweetkind, D.","contributorId":83645,"corporation":false,"usgs":true,"family":"Sweetkind","given":"D.","affiliations":[],"preferred":false,"id":406113,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70025666,"text":"70025666 - 2003 - Application of geographic information systems and remote sensing for quantifying patterns of erosion and water quality","interactions":[],"lastModifiedDate":"2012-03-12T17:20:22","indexId":"70025666","displayToPublicDate":"2003-01-01T00:00:00","publicationYear":"2003","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1924,"text":"Hydrological Processes","active":true,"publicationSubtype":{"id":10}},"title":"Application of geographic information systems and remote sensing for quantifying patterns of erosion and water quality","docAbstract":"[No abstract available]","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Hydrological Processes","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1002/hyp.1167","issn":"08856087","usgsCitation":"Ritchie, J., Walling, D., and Peters, J., 2003, Application of geographic information systems and remote sensing for quantifying patterns of erosion and water quality: Hydrological Processes, v. 17, no. 5, p. 885-886, https://doi.org/10.1002/hyp.1167.","startPage":"885","endPage":"886","numberOfPages":"2","costCenters":[],"links":[{"id":208646,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1002/hyp.1167"},{"id":234529,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"17","issue":"5","noUsgsAuthors":false,"publicationDate":"2003-03-14","publicationStatus":"PW","scienceBaseUri":"5059ec9ee4b0c8380cd493af","contributors":{"authors":[{"text":"Ritchie, J.C.","contributorId":89299,"corporation":false,"usgs":true,"family":"Ritchie","given":"J.C.","email":"","affiliations":[],"preferred":false,"id":406091,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Walling, D.E.","contributorId":24481,"corporation":false,"usgs":true,"family":"Walling","given":"D.E.","email":"","affiliations":[],"preferred":false,"id":406089,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Peters, J.","contributorId":58066,"corporation":false,"usgs":true,"family":"Peters","given":"J.","affiliations":[],"preferred":false,"id":406090,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70025642,"text":"70025642 - 2003 - The role of microbial reductive dechlorination of TCE at a phytoremediation site","interactions":[],"lastModifiedDate":"2020-01-05T14:44:38","indexId":"70025642","displayToPublicDate":"2003-01-01T00:00:00","publicationYear":"2003","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2064,"text":"International Journal of Phytoremediation","active":true,"publicationSubtype":{"id":10}},"title":"The role of microbial reductive dechlorination of TCE at a phytoremediation site","docAbstract":"In April 1996, a phytoremediation field demonstration site at the Naval Air Station, Fort Worth, Texas, was developed to remediate shallow oxic ground water (<3.7 m deep) contaminated with chlorinated ethenes. Microbial populations were sampled in February and June 1998. The populations under the newly planted cottonwood trees had not yet matured to an anaerobic community that could dechlorinate trichloroethene (TCE) to cis-1,2-dichloroethene (DCE); however, the microbial population under a mature (∼22-year-old) cottonwood tree about 30 m southwest of the plantings had a mature anaerobic population capable of dechlorinating TCE to DCE, and DCE to vinyl chloride (VC). Oxygen-free sediment incubations with contaminated groundwater also demonstrated that resident microorganisms were capable of the dechlorination of TCE to DCE. This suggests that a sufficient amount of organic material is present for microbial dechlorination in aquifer microniches where dissolved O2 concentrations are low. Phenol, benzoic acid, acetic acid, and a cyclic hydrocarbon, compounds consistent with the degradation of root exudates and complex aromatic compounds, were identified by gas chromatography/mass spectrometry (GC/MS) in sediment samples under the mature cottonwood tree. Elsewhere at the site, transpiration and degradation by the cottonwood trees appears to be responsible for loss of chlorinated ethenes.
Uranium binding to bone charcoal and bone meal apatite materials was investigated using U LIII-edge EXAFS spectroscopy and synchrotron source XRD measurements of laboratory batch preparations in the absence and presence of dissolved carbonate. Pelletized bone char apatite recovered from a permeable reactive barrier (PRB) at Fry Canyon, UT, was also studied. EXAFS analyses indicate that U(VI) sorption in the absence of dissolved carbonate occurred by surface complexation of U(VI) for sorbed concentrations ≤ 5500 μg U(VI)/g for all materials with the exception of crushed bone char pellets. Either a split or a disordered equatorial oxygen shell was observed, consistent with complexation of uranyl by the apatite surface. A second shell of atoms at a distance of 2.9 Å was required to fit the spectra of samples prepared in the presence of dissolved carbonate (4.8 mM total) and is interpreted as formation of ternary carbonate complexes with sorbed U(VI). A U−P distance at 3.5−3.6 Å was found for most samples under conditions where uranyl phosphate phases did not form, which is consistent with monodentate coordination of uranyl by phosphate groups in the apatite surface. At sorbed concentrations ≥ 5500 μg U(VI)/g in the absence of dissolved carbonate, formation of the uranyl phosphate solid phase, chernikovite, was observed. The presence of dissolved carbonate (4.8 mM total) suppressed the formation of chernikovite, which was not detected even with sorbed U(VI) up to 12 300 μg U(VI)/g in batch samples of bone meal, bone charcoal, and reagent-grade hydroxyapatite. EXAFS spectra of bone char samples recovered from the Fry Canyon PRB were comparable to laboratory samples in the presence of dissolved carbonate where U(VI) sorption occurred by surface complexation. Our findings demonstrate that uranium uptake by bone apatite will probably occur by surface complexation instead of precipitation of uranyl phosphate phases under the groundwater conditions found at many U-contaminated sites.
Analysis of a 72-h, constant-rate aquifer test conducted in a coarse-grained and highly permeable, glacial outwash deposit on Cape Cod, Massachusetts revealed that drawdowns measured in 20 piezometers located at various depths below the water table and distances from the pumped well were significantly influenced by effects of drainage from the vadose zone. The influence was greatest in piezometers located close to the water table and diminished with increasing depth. The influence of the vadose zone was evident from a gap, in the intermediate-time zone, between measured drawdowns and drawdowns computed under the assumption that drainage from the vadose zone occurred instantaneously in response to a decline in the elevation of the water table. By means of an analytical model that was designed to account for time-varying drainage, simulated drawdowns could be closely fitted to measured drawdowns regardless of the piezometer locations. Because of the exceptional quality and quantity of the data and the relatively small aquifer heterogeneity, it was possible by inverse modeling to estimate all relevant aquifer parameters and a set of three empirical constants used in the upper-boundary condition to account for the dynamic drainage process. The empirical constants were used to define a one-dimensional (1D) drainage versus time curve that is assumed to be representative of the bulk material overlying the water table. The curve was inverted with a parameter estimation algorithm and a 1D numerical model for variably saturated flow to obtain soil-moisture retention curves and unsaturated hydraulic conductivity relationships defined by the Brooks and Corey equations. Direct analysis of the aquifer-test data using a parameter estimation algorithm and a two-dimensional, axisymmetric numerical model for variably saturated flow yielded similar soil-moisture characteristics. Results suggest that hectare-scale soil-moisture characteristics are different from core-scale predictions and even relatively small amounts of fine-grained material and heterogeneity can dominate the large-scale soil-moisture characteristics and aquifer response.
Conditional distribution coefficients (KDOM‘) for Hg(II) binding to seven dissolved organic matter (DOM) isolates were measured at environmentally relevant ratios of Hg(II) to DOM. The results show that KDOM‘ values for different types of samples (humic acids, fulvic acids, hydrophobic acids) isolated from diverse aquatic environments were all within 1 order of magnitude (1022.5±1.0−1023.5±1.0 L kg-1), suggesting similar Hg(II) binding environments, presumably involving thiol groups, for the different isolates. KDOM‘ values decreased at low pHs (4) compared to values at pH 7, indicating proton competition for the strong Hg(II) binding sites. Chemical modeling of Hg(II)−DOM binding at different pH values was consistent with bidentate binding of Hg(II) by one thiol group (pKa = 10.3) and one other group (pKa = 6.3) in the DOM, which is in agreement with recent results on the structure of Hg(II)−DOM bonds obtained by extended X-ray absorption fine structure spectroscopy (EXAFS).
An understanding of unsaturated flow and potential recharge in interdrainage semiarid and arid regions is critical for quantification of water resources and contaminant transport. We evaluated system response to paleoclimatic forcing using water potential and Cl profiles and modeling of nonisothermal liquid and vapor flow and Cl transport at semiarid (High Plains, Texas) and arid (Chihuahuan Desert, Texas; Amargosa Desert, Nevada) sites. Infiltration in response to current climatic forcing is restricted to the shallow (∼0.3–3 m) subsurface. Subsurface Cl accumulations correspond to time periods of 9–90 kyr. Bulge-shaped Cl profiles generally represent accumulation during the Holocene (9–16 kyr). Lower Cl concentrations at depth reflect higher water fluxes (0.04–8.4 mm/yr) during the Pleistocene and earlier times. Low water potentials and upward gradients indicate current drying conditions. Nonisothermal liquid and vapor flow simulations indicate that upward flow for at least 1–2 kyr in the High Plains and for 12–16 kyr at the Chihuahuan and Amargosa desert sites is required to reproduce measured upward water potential gradients and that recharge is negligible (<0.1 mm/yr) in these interdrainage areas.
","language":"English","publisher":"AGU Publications","doi":"10.1029/2002WR001604","usgsCitation":"Scanlon, B., Keese, K., Reedy, R., Simunek, J., and Andraski, B.J., 2003, Variations in flow and transport in thick desert vadose zones in response to paleoclimatic forcing (0-90 kyr): Field measurements, modeling, and uncertainties: Water Resources Research, v. 39, no. 7, Article 1179; 17 p., https://doi.org/10.1029/2002WR001604.","productDescription":"Article 1179; 17 p.","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":235893,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"39","issue":"7","noUsgsAuthors":false,"publicationDate":"2003-07-10","publicationStatus":"PW","scienceBaseUri":"505bc17de4b08c986b32a5d6","contributors":{"authors":[{"text":"Scanlon, Bridget R.","contributorId":74093,"corporation":false,"usgs":true,"family":"Scanlon","given":"Bridget R.","affiliations":[],"preferred":false,"id":404983,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Keese, K.","contributorId":15813,"corporation":false,"usgs":true,"family":"Keese","given":"K.","affiliations":[],"preferred":false,"id":404980,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Reedy, R.C.","contributorId":80880,"corporation":false,"usgs":true,"family":"Reedy","given":"R.C.","email":"","affiliations":[],"preferred":false,"id":404982,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Simunek, Jirka","contributorId":9440,"corporation":false,"usgs":false,"family":"Simunek","given":"Jirka","email":"","affiliations":[],"preferred":false,"id":404979,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Andraski, Brian J. 0000-0002-2086-0417 andraski@usgs.gov","orcid":"https://orcid.org/0000-0002-2086-0417","contributorId":168800,"corporation":false,"usgs":true,"family":"Andraski","given":"Brian","email":"andraski@usgs.gov","middleInitial":"J.","affiliations":[{"id":438,"text":"National Research Program - Western Branch","active":true,"usgs":true},{"id":465,"text":"Nevada Water Science Center","active":true,"usgs":true},{"id":38175,"text":"Toxics Substances Hydrology Program","active":true,"usgs":true}],"preferred":false,"id":404981,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":70025351,"text":"70025351 - 2003 - Inverse modeling of BTEX dissolution and biodegradation at the Bemidji, MN crude-oil spill site","interactions":[],"lastModifiedDate":"2018-11-16T10:28:36","indexId":"70025351","displayToPublicDate":"2003-01-01T00:00:00","publicationYear":"2003","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2233,"text":"Journal of Contaminant Hydrology","active":true,"publicationSubtype":{"id":10}},"title":"Inverse modeling of BTEX dissolution and biodegradation at the Bemidji, MN crude-oil spill site","docAbstract":"The U.S. Geological Survey (USGS) solute transport and biodegradation code BIOMOC was used in conjunction with the USGS universal inverse modeling code UCODE to quantify field-scale hydrocarbon dissolution and biodegradation at the USGS Toxic Substances Hydrology Program crude-oil spill research site located near Bemidji, MN. This inverse modeling effort used the extensive historical data compiled at the Bemidji site from 1986 to 1997 and incorporated a multicomponent transport and biodegradation model. Inverse modeling was successful when coupled transport and degradation processes were incorporated into the model and a single dissolution rate coefficient was used for all BTEX components. Assuming a stationary oil body, we simulated benzene, toluene, ethylbenzene, m,p-xylene, and o-xylene (BTEX) concentrations in the oil and ground water, respectively, as well as dissolved oxygen. Dissolution from the oil phase and aerobic and anaerobic degradation processes were represented. The parameters estimated were the recharge rate, hydraulic conductivity, dissolution rate coefficient, individual first-order BTEX anaerobic degradation rates, and transverse dispersivity. Results were similar for simulations obtained using several alternative conceptual models of the hydrologic system and biodegradation processes. The dissolved BTEX concentration data were not sufficient to discriminate between these conceptual models. The calibrated simulations reproduced the general large-scale evolution of the plume, but did not reproduce the observed small-scale spatial and temporal variability in concentrations. The estimated anaerobic biodegradation rates for toluene and o-xylene were greater than the dissolution rate coefficient. However, the estimated anaerobic biodegradation rates for benzene, ethylbenzene, and m,p-xylene were less than the dissolution rate coefficient. The calibrated model was used to determine the BTEX mass balance in the oil body and groundwater plume. Dissolution from the oil body was greatest for compounds with large effective solubilities (benzene) and with large degradation rates (toluene and o-xylene). Anaerobic degradation removed 77% of the BTEX that dissolved into the water phase and aerobic degradation removed 17%. Although goodness-of-fit measures for the alternative conceptual models were not significantly different, predictions made with the models were quite variable.
As part of the World Climate Research Program's (WCRPs) Global Energy and Water-Cycle Experiment (GEWEX) Continental-scale International Project (GCIP), a preliminary water and energy budget synthesis (WEBS) was developed for the period 1996-1999 fromthe \"best available\" observations and models. Besides this summary paper, a companion CD-ROM with more extensive discussion, figures, tables, and raw data is available to the interested researcher from the GEWEX project office, the GAPP project office, or the first author. An updated online version of the CD-ROM is also available at http://ecpc.ucsd.edu/gcip/webs.htm/. Observations cannot adequately characterize or \"close\" budgets since too many fundamental processes are missing. Models that properly represent the many complicated atmospheric and near-surface interactions are also required. This preliminary synthesis therefore included a representative global general circulation model, regional climate model, and a macroscale hydrologic model as well as a global reanalysis and a regional analysis. By the qualitative agreement among the models and available observations, it did appear that we now qualitatively understand water and energy budgets of the Mississippi River Basin. However, there is still much quantitative uncertainty. In that regard, there did appear to be a clear advantage to using a regional analysis over a global analysis or a regional simulation over a global simulation to describe the Mississippi River Basin water and energy budgets. There also appeared to be some advantage to using a macroscale hydrologic model for at least the surface water budgets. Copyright 2003 by the American Geophysical Union.
","language":"English","publisher":"Wiley","doi":"10.1029/2002JD002583","issn":"01480227","usgsCitation":"Roads, J., Lawford, R., Bainto, E., Berbery, E., Chen, S., Fekete, B., Gallo, K., Grundstein, A., Higgins, W., Kanamitsu, M., Krajewski, W., Lakshmi, V., Leathers, D., Lettenmaier, D., Luo, L., Maurer, E., Meyers, T., Miller, D., Mitchell, K., Mote, T., Pinker, R., Reichler, T., Robinson, D., Robock, A., Smith, J., Srinivasan, G., Verdin, K., Vinnikov, K., Vonder, H.T., Vorosmarty, C., Williams, S., and Yarosh, E., 2003, GCIP water and energy budget synthesis (WEBS): Journal of Geophysical Research D: Atmospheres, v. 108, no. 16, https://doi.org/10.1029/2002JD002583.","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":222,"text":"Earth Resources Observation and Science (EROS) Center","active":true,"usgs":true}],"links":[{"id":235959,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"108","issue":"16","noUsgsAuthors":false,"publicationDate":"2003-08-12","publicationStatus":"PW","scienceBaseUri":"505a1445e4b0c8380cd54990","contributors":{"authors":[{"text":"Roads, J.","contributorId":48370,"corporation":false,"usgs":true,"family":"Roads","given":"J.","email":"","affiliations":[],"preferred":false,"id":404375,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Lawford, R.","contributorId":106295,"corporation":false,"usgs":true,"family":"Lawford","given":"R.","email":"","affiliations":[],"preferred":false,"id":404392,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Bainto, E.","contributorId":100593,"corporation":false,"usgs":true,"family":"Bainto","given":"E.","email":"","affiliations":[],"preferred":false,"id":404390,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Berbery, E.","contributorId":45096,"corporation":false,"usgs":true,"family":"Berbery","given":"E.","email":"","affiliations":[],"preferred":false,"id":404373,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Chen, S.","contributorId":7856,"corporation":false,"usgs":true,"family":"Chen","given":"S.","affiliations":[],"preferred":false,"id":404361,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Fekete, B.","contributorId":81297,"corporation":false,"usgs":true,"family":"Fekete","given":"B.","email":"","affiliations":[],"preferred":false,"id":404384,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Gallo, K. 0000-0001-9162-5011 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0000-0002-6114-4660","orcid":"https://orcid.org/0000-0002-6114-4660","contributorId":33505,"corporation":false,"usgs":true,"family":"Verdin","given":"K.L.","affiliations":[],"preferred":false,"id":404371,"contributorType":{"id":1,"text":"Authors"},"rank":27},{"text":"Vinnikov, K.","contributorId":29620,"corporation":false,"usgs":true,"family":"Vinnikov","given":"K.","email":"","affiliations":[],"preferred":false,"id":404369,"contributorType":{"id":1,"text":"Authors"},"rank":28},{"text":"Vonder, Haar T.","contributorId":31560,"corporation":false,"usgs":true,"family":"Vonder","given":"Haar","email":"","middleInitial":"T.","affiliations":[],"preferred":false,"id":404370,"contributorType":{"id":1,"text":"Authors"},"rank":29},{"text":"Vorosmarty, C.","contributorId":79276,"corporation":false,"usgs":true,"family":"Vorosmarty","given":"C.","affiliations":[],"preferred":false,"id":404383,"contributorType":{"id":1,"text":"Authors"},"rank":30},{"text":"Williams, 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strain MLS10","docAbstract":"The respiratory arsenate reductase from the Gram-positive, haloalkaliphile, Bacillus selenitireducens strain MLS10 was purified and characterized. It is a membrane bound heterodimer (150 kDa) composed of two subunits ArrA (110 kDa) and ArrB (34 kDa), with an apparent Km for arsenate of 34 µM and Vmax of 2.5 µmol min−1 mg−1. Optimal activity occurred at pH 9.5 and 150 g l−1 of NaCl. Metal analysis (inductively coupled plasma mass spectrometry) of the holoenzyme and sequence analysis of the catalytic subunit (ArrA; the gene fr which was cloned and sequenced) indicate it is a member of the DMSO reductase family of molybdoproteins.
","language":"English","publisher":"Oxford Academic","doi":"10.1016/S0378-1097(03)00609-8","issn":"03781097","usgsCitation":"Afkar, E., Lisak, J., Saltikov, C., Basu, P., Oremland, R.S., and Stolz, J., 2003, The respiratory arsenate reductase from Bacillus selenitireducens strain MLS10: FEMS Microbiology Letters, v. 226, no. 1, p. 107-112, https://doi.org/10.1016/S0378-1097(03)00609-8.","productDescription":"6 p.","startPage":"107","endPage":"112","numberOfPages":"6","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":478513,"rank":1,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1016/s0378-1097(03)00609-8","text":"Publisher Index Page"},{"id":235923,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"226","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505baf35e4b08c986b324627","contributors":{"authors":[{"text":"Afkar, E.","contributorId":105894,"corporation":false,"usgs":true,"family":"Afkar","given":"E.","email":"","affiliations":[],"preferred":false,"id":404354,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Lisak, J.","contributorId":36715,"corporation":false,"usgs":true,"family":"Lisak","given":"J.","email":"","affiliations":[],"preferred":false,"id":404350,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Saltikov, C.","contributorId":77722,"corporation":false,"usgs":true,"family":"Saltikov","given":"C.","email":"","affiliations":[],"preferred":false,"id":404351,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Basu, P.","contributorId":35527,"corporation":false,"usgs":true,"family":"Basu","given":"P.","email":"","affiliations":[],"preferred":false,"id":404349,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Oremland, Ronald S. 0000-0001-7382-0147 roremlan@usgs.gov","orcid":"https://orcid.org/0000-0001-7382-0147","contributorId":931,"corporation":false,"usgs":true,"family":"Oremland","given":"Ronald","email":"roremlan@usgs.gov","middleInitial":"S.","affiliations":[{"id":438,"text":"National Research Program - Western Branch","active":true,"usgs":true},{"id":37277,"text":"WMA - Earth System Processes Division","active":true,"usgs":true}],"preferred":true,"id":778883,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Stolz, J.F.","contributorId":94022,"corporation":false,"usgs":true,"family":"Stolz","given":"J.F.","email":"","affiliations":[],"preferred":false,"id":404352,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}} ,{"id":70025234,"text":"70025234 - 2003 - Importance of Sediment-Water Interactions in Coeur d'Alene Lake, Idaho, USA: Management Implications","interactions":[],"lastModifiedDate":"2019-05-01T09:46:24","indexId":"70025234","displayToPublicDate":"2003-01-01T00:00:00","publicationYear":"2003","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1547,"text":"Environmental Management","active":true,"publicationSubtype":{"id":10}},"title":"Importance of Sediment-Water Interactions in Coeur d'Alene Lake, Idaho, USA: Management Implications","docAbstract":"A field study at Coeur d'Alene Lake, Idaho, USA, was conducted between October 1998 and August 2001 to examine the potential importance of sediment-water interactions on contaminant transport and to provide the first direct measurements of the benthic flux of dissolved solutes of environmental concern in this lake. Because of potential ecological effects, dissolved zinc and orthophosphate were the solutes of primary interest. Results from deployments of an in situ flux chamber indicated that benthic fluxes of dissolved Zn and orthophosphate were comparable in magnitude to riverine inputs. Tracer analyses and benthic-community metrics provided evidence that solute benthic flux were diffusion-controlled at the flux-chamber deployment sites. That is, effects of biomixing (or bioturbation) and ground-water interactions did not strongly influence benthic flux. Remediation efforts in the river might not produce desired water-quality effects in the lake because imposed shifts in concentration gradients near the sediment-water interface would generate a benthic feedback response. Therefore, development of water-quality models to justify remediation strategies requires consideration of contaminant flux between the water column and underlying sediment in basins that have been affected by long-term (decadal) anthropogenic activities.","language":"English","publisher":"Springer","doi":"10.1007/s00267-003-0020-7","issn":"0364152X","usgsCitation":"Kuwabara, J., Carter, J., Topping, B., Fend, S., Woods, P.F., Berelson, W., and Balistrieri, L.S., 2003, Importance of Sediment-Water Interactions in Coeur d'Alene Lake, Idaho, USA: Management Implications: Environmental Management, v. 32, no. 3, p. 348-359, https://doi.org/10.1007/s00267-003-0020-7.","productDescription":"12 p.","startPage":"348","endPage":"359","costCenters":[{"id":191,"text":"Colorado Water Science Center","active":true,"usgs":true},{"id":312,"text":"Geology, Minerals, Energy, and Geophysics Science Center","active":true,"usgs":true},{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":235886,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":209440,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1007/s00267-003-0020-7"}],"country":"United States","state":"Idaho","otherGeospatial":"Coeur d’Alene Lake","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -117,\n 47.25\n ],\n [\n -115.5,\n 47.25\n ],\n [\n -115.5,\n 47.75\n ],\n [\n -117,\n 47.75\n ],\n [\n -117,\n 47.25\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"32","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a3932e4b0c8380cd6183c","contributors":{"authors":[{"text":"Kuwabara, J.S.","contributorId":57905,"corporation":false,"usgs":true,"family":"Kuwabara","given":"J.S.","email":"","affiliations":[],"preferred":false,"id":404345,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Carter, J.L.","contributorId":26030,"corporation":false,"usgs":true,"family":"Carter","given":"J.L.","email":"","affiliations":[],"preferred":false,"id":404342,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Topping, B.R.","contributorId":97541,"corporation":false,"usgs":true,"family":"Topping","given":"B.R.","email":"","affiliations":[],"preferred":false,"id":404347,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Fend, S.V. 0000-0002-4638-6602","orcid":"https://orcid.org/0000-0002-4638-6602","contributorId":99702,"corporation":false,"usgs":true,"family":"Fend","given":"S.V.","affiliations":[],"preferred":false,"id":404348,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Woods, P. F.","contributorId":97509,"corporation":false,"usgs":true,"family":"Woods","given":"P.","email":"","middleInitial":"F.","affiliations":[],"preferred":false,"id":404346,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Berelson, W.M.","contributorId":44337,"corporation":false,"usgs":true,"family":"Berelson","given":"W.M.","email":"","affiliations":[],"preferred":false,"id":404343,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Balistrieri, Laurie S. 0000-0002-6359-3849 balistri@usgs.gov","orcid":"https://orcid.org/0000-0002-6359-3849","contributorId":1406,"corporation":false,"usgs":true,"family":"Balistrieri","given":"Laurie","email":"balistri@usgs.gov","middleInitial":"S.","affiliations":[{"id":191,"text":"Colorado Water Science Center","active":true,"usgs":true},{"id":312,"text":"Geology, Minerals, Energy, and Geophysics Science Center","active":true,"usgs":true},{"id":200,"text":"Coop Res Unit Seattle","active":true,"usgs":true},{"id":662,"text":"Western Mineral and Environmental Resources Science Center","active":true,"usgs":true}],"preferred":true,"id":761875,"contributorType":{"id":1,"text":"Authors"},"rank":7}]}} ,{"id":70025233,"text":"70025233 - 2003 - Numerical modeling of coupled nitrification-denitrification in sediment perfusion cores from the hyporheic zone of the Shingobee River, MN","interactions":[],"lastModifiedDate":"2018-11-19T09:45:02","indexId":"70025233","displayToPublicDate":"2003-01-01T00:00:00","publicationYear":"2003","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":664,"text":"Advances in Water Resources","active":true,"publicationSubtype":{"id":10}},"title":"Numerical modeling of coupled nitrification-denitrification in sediment perfusion cores from the hyporheic zone of the Shingobee River, MN","docAbstract":"Nitrification and denitrification kinetics in sediment perfusion cores were numerically modeled and compared to experiments on cores from the Shingobee River MN, USA. The experimental design incorporated mixing groundwater discharge with stream water penetration into the cores, which provided a well-defined, one-dimensional simulation of in situ hydrologic conditions. Ammonium (NH4+) and nitrate (NO3−) concentration gradients suggested the upper region of the cores supported coupled nitrification–denitrification, where groundwater-derived NH4+ was first oxidized to NO3− then subsequently reduced via denitrification to N2. Nitrification and denitrification were modeled using a Crank–Nicolson finite difference approximation to a one-dimensional advection–dispersion equation. Both processes were modeled using first-order reaction kinetics because substrate concentrations (NH4+ and NO3−) were much smaller than published Michaelis constants. Rate coefficients for nitrification and denitrification ranged from 0.2 to 15.8 h−1 and 0.02 to 8.0 h−1, respectively. The rate constants followed an Arrhenius relationship between 7.5 and 22 °C. Activation energies for nitrification and denitrification were 162 and 97.3 kJ/mol, respectively. Seasonal NH4+ concentration patterns in the Shingobee River were accurately simulated from the relationship between perfusion core temperature and NH4+ flux to the overlying water. The simulations suggest that NH4+ in groundwater discharge is controlled by sediment nitrification that, consistent with its activation energy, is strongly temperature dependent.
Stable water isotope (δ18O, δD) data from a high elevation (5100 masl) ice core recovered from the Tien Shan Mountains, Kyrgyzstan, display a seasonal cycle in deuterium excess (d = δD - 8*δ18O) related to changes in the regional hydrologic cycle during 1994-2000. While there is a strong correlation (r2 = 0.98) between δ18O and δD in the ice core samples, the regression slope (6.9) and mean d value (23.0) are significantly different than the global meteoric water line values. The resulting time-series ice core d profile contains distinct winter maxima and summer minima, with a yearly d amplitude of ∼15-20‰. Local-scale processes that may affect d values preserved in the ice core are not consistent with the observed seasonal variability. Data from Central Asian monitoring sites in the Global Network of Isotopes in Precipitation (GNIP) have similar seasonal d changes. We suggest that regional-scale hydrological conditions, including seasonal changes in moisture source, transport, and recycling in the Caspian/Aral Sea region, are responsible for the observed spatial and temporal d variability.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/2003GL017896","issn":"00948276","usgsCitation":"Kreutz, K., Wake, C., Aizen, V., Cecil, L., and Synal, H., 2003, Seasonal deuterium excess in a Tien Shan ice core: Influence of moisture transport and recycling in Central Asia: Geophysical Research Letters, v. 30, no. 18, 4 p., https://doi.org/10.1029/2003GL017896.","productDescription":"4 p.","costCenters":[],"links":[{"id":478477,"rank":0,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/2003gl017896","text":"Publisher Index Page"},{"id":387716,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"30","issue":"18","noUsgsAuthors":false,"publicationDate":"2003-09-17","publicationStatus":"PW","scienceBaseUri":"505b8890e4b08c986b316a2e","contributors":{"authors":[{"text":"Kreutz, K.J.","contributorId":46712,"corporation":false,"usgs":true,"family":"Kreutz","given":"K.J.","affiliations":[],"preferred":false,"id":404209,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Wake, C.P.","contributorId":85353,"corporation":false,"usgs":true,"family":"Wake","given":"C.P.","email":"","affiliations":[],"preferred":false,"id":404212,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Aizen, V.B.","contributorId":24972,"corporation":false,"usgs":true,"family":"Aizen","given":"V.B.","email":"","affiliations":[],"preferred":false,"id":404208,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Cecil, L. DeWayne","contributorId":66856,"corporation":false,"usgs":true,"family":"Cecil","given":"L. DeWayne","affiliations":[],"preferred":false,"id":404210,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Synal, H.-A.","contributorId":78501,"corporation":false,"usgs":true,"family":"Synal","given":"H.-A.","email":"","affiliations":[],"preferred":false,"id":404211,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":70025170,"text":"70025170 - 2003 - Arsenic speciation and reactivity in poultry litter","interactions":[],"lastModifiedDate":"2018-11-19T10:51:09","indexId":"70025170","displayToPublicDate":"2003-01-01T00:00:00","publicationYear":"2003","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1565,"text":"Environmental Science & Technology","onlineIssn":"1520-5851","printIssn":"0013-936X","active":true,"publicationSubtype":{"id":10}},"title":"Arsenic speciation and reactivity in poultry litter","docAbstract":"Recent U.S. government action to lower the maximum concentration levels (MCL) of total arsenic (As) (10 ppb) in drinking water has raised serious concerns about the agricultural use of As-containing biosolids such as poultry litter (PL). In this study, solid-state chemical speciation, desorbability, and total levels of As in PL and long-term amended soils were investigated using novel synchrotron-based probing techniques (microfocused (μ) synchrotron X-ray fluorescence (SXRF) and μ-X-ray absorption near-edge structure (XANES) spectroscopies) coupled with chemical digestion and batch experiments. The total As levels in the PL were as high as ≈50 mg kg-1, and As(II/III and V) was always concentrated in abundant needle-shaped microscopic particles (≈20 μm × 850 μm) associated with Ca, Cu, and Fe and to a lesser extent with S, Cl, and Zn. Post-edge XANES features of litter particles are dissimilar to those of the organo-As(V) compound in poultry feed (i.e., roxarsone), suggesting possible degradation/transformation of roxarsone in the litter and/or in poultry digestive tracts. The extent of As desorption from the litter increased with increasing time and pH from 4.5 to 7, but at most 15% of the total As was released after 5 d at pH 7, indicating the presence of insoluble phases and/or strongly retained soluble compounds. No significant As accumulation (<15 mg kg-1) was found in long-term PL-amended agricultural surface soils. This suggests that As in the PL may have undergone surface and subsurface transport processes. Our research results raise concerns about long-term PL amendment effects on As contamination in surrounding soil−water environments.
Despite a rapidly growing literature on analytical methods and field applications of O isotope-ratio measurements of NO3− in environmental studies, there is evidence that the reported data may not be comparable because reference materials with widely varying δ18O values have not been readily available. To address this problem, we prepared large quantities of two nitrate salts with contrasting O isotopic compositions for distribution as reference materials for O isotope-ratio measurements: USGS34 (KNO3) with low δ18O and USGS35 (NaNO3) with high δ18O and ‘mass-independent’ δ17O. The procedure used to produce USGS34 involved equilibration of HNO3 with 18O-depleted meteoric water. Nitric acid equilibration is proposed as a simple method for producing laboratory NO3− reference materials with a range of δ18O values and normal (mass-dependent) 18O:17O:16O variation. Preliminary data indicate that the equilibrium O isotope-fractionation factor (α) between [NO3−] and H2O decreases with increasing temperature from 1.0215 at 22°C to 1.0131 at 100°C. USGS35 was purified from the nitrate ore deposits of the Atacama Desert in Chile and has a high 17O:18O ratio owing to its atmospheric origin. These new reference materials, combined with previously distributed NO3− isotopic reference materials IAEA-N3 (=IAEA-NO-3) and USGS32, can be used to calibrate local laboratory reference materials for determining offset values, scale factors, and mass-independent effects on N and O isotope-ratio measurements in a wide variety of environmental NO3− samples. Preliminary analyses yield the following results (normalized with respect to VSMOW and SLAP, with reproducibilities of ±0.2–0.3‰, 1σ): IAEA-N3 has δ18O = +25.6‰ and δ17O = +13.2‰; USGS32 has δ18O = +25.7‰; USGS34 has δ18O = −27.9‰ and δ17O = −14.8‰; and USGS35 has δ18O = +57.5‰ and δ17O = +51.5‰.
","language":"English","publisher":"Wiley","doi":"10.1002/rcm.1123","issn":"09514198","usgsCitation":"Böhlke, J., Mroczkowski, S., and Coplen, T., 2003, Oxygen isotopes in nitrate: New reference materials for 18O:17O:16O measurements and observations on nitrate-water equilibration: Rapid Communications in Mass Spectrometry, v. 17, no. 16, p. 1835-1846, https://doi.org/10.1002/rcm.1123.","productDescription":"12 p.","startPage":"1835","endPage":"1846","numberOfPages":"12","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":236061,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"17","issue":"16","noUsgsAuthors":false,"publicationDate":"2003-07-04","publicationStatus":"PW","scienceBaseUri":"505a72b1e4b0c8380cd76c41","contributors":{"authors":[{"text":"Böhlke, J.K. 0000-0001-5693-6455","orcid":"https://orcid.org/0000-0001-5693-6455","contributorId":96696,"corporation":false,"usgs":true,"family":"Böhlke","given":"J.K.","affiliations":[],"preferred":false,"id":403975,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Mroczkowski, S.J.","contributorId":58673,"corporation":false,"usgs":true,"family":"Mroczkowski","given":"S.J.","email":"","affiliations":[],"preferred":false,"id":403974,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Coplen, T.B.","contributorId":34147,"corporation":false,"usgs":true,"family":"Coplen","given":"T.B.","affiliations":[],"preferred":false,"id":403973,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70024950,"text":"70024950 - 2003 - Effect of hydrologic and geochemical conditions on oxygen-enhanced bioremediation in a gasoline-contaminated aquifer","interactions":[],"lastModifiedDate":"2018-11-16T10:41:35","indexId":"70024950","displayToPublicDate":"2003-01-01T00:00:00","publicationYear":"2003","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1042,"text":"Bioremediation Journal","active":true,"publicationSubtype":{"id":10}},"title":"Effect of hydrologic and geochemical conditions on oxygen-enhanced bioremediation in a gasoline-contaminated aquifer","docAbstract":"The effect of pre-existing factors, e.g., hydrologic, geochemical, and microbiological properties, on the results of oxygen addition to a reformulated gasoline-contaminated groundwater system was studied. Oxygen addition with an oxygen-release compound (a proprietary form of magnesium peroxide produced different results with respect to dissolved oxygen (DO) generation and contaminant decrease in the two locations. Oxygen-release compound injected at the former UST source area did not significantly change measured concentrations of DO, benzene, toluene, or MTBE. Conversely, oxygen-release compound injected 200 m downgradient of the former UST source area rapidly increased DO levels, and benzene, toluene, and MTBE concentrations decreased substantially. The different results could be related to differences in hydrologic and geochemical conditions that characterized the two locations prior to oxygen addition. The lack of recharge to ground water in the paved UST source area led to a much larger geochemical sink for DO compared to ground water in the unpaved area.","language":"English","publisher":"Taylor and Francis","doi":"10.1080/713607983","issn":"10889868","usgsCitation":"Landmeyer, J., and Bradley, P., 2003, Effect of hydrologic and geochemical conditions on oxygen-enhanced bioremediation in a gasoline-contaminated aquifer: Bioremediation Journal, v. 7, no. 3-4, p. 165-177, https://doi.org/10.1080/713607983.","productDescription":"13 p.","startPage":"165","endPage":"177","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":232834,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":269728,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1080/713607983"}],"volume":"7","issue":"3-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a05b6e4b0c8380cd50f07","contributors":{"authors":[{"text":"Landmeyer, J. E.","contributorId":91140,"corporation":false,"usgs":true,"family":"Landmeyer","given":"J. E.","affiliations":[],"preferred":false,"id":403227,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Bradley, P. M. 0000-0001-7522-8606","orcid":"https://orcid.org/0000-0001-7522-8606","contributorId":29465,"corporation":false,"usgs":true,"family":"Bradley","given":"P. M.","affiliations":[],"preferred":false,"id":403226,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70024926,"text":"70024926 - 2003 - Modeling radium and radon transport through soil and vegetation","interactions":[],"lastModifiedDate":"2012-03-12T17:20:05","indexId":"70024926","displayToPublicDate":"2003-01-01T00:00:00","publicationYear":"2003","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2233,"text":"Journal of Contaminant Hydrology","active":true,"publicationSubtype":{"id":10}},"title":"Modeling radium and radon transport through soil and vegetation","docAbstract":"A one-dimensional flow and transport model was developed to describe the movement of two fluid phases, gas and water, within a porous medium and the transport of 226Ra and 222Rn within and between these two phases. Included in this model is the vegetative uptake of water and aqueous 226Ra and 222Rn that can be extracted from the soil via the transpiration stream. The mathematical model is formulated through a set of phase balance equations and a set of species balance equations. Mass exchange, sink terms and the dependence of physical properties upon phase composition couple the two sets of equations. Numerical solution of each set, with iteration between the sets, is carried out leading to a set-iterative compositional model. The Petrov-Galerkin finite element approach is used to allow for upstream weighting if required for a given simulation. Mass lumping improves solution convergence and stability behavior. The resulting numerical model was applied to four problems and was found to produce accurate, mass conservative solutions when compared to published experimental and numerical results and theoretical column experiments. Preliminary results suggest that the model can be used as an investigative tool to determine the feasibility of phytoremediating radium and radon-contaminated soil. ?? 2003 Elsevier Science B.V. All rights reserved.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Contaminant Hydrology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0169-7722(03)00032-9","issn":"01697722","usgsCitation":"Kozak, J., Reeves, H.W., and Lewis, B., 2003, Modeling radium and radon transport through soil and vegetation: Journal of Contaminant Hydrology, v. 66, no. 3-4, p. 179-200, https://doi.org/10.1016/S0169-7722(03)00032-9.","startPage":"179","endPage":"200","numberOfPages":"22","costCenters":[],"links":[{"id":207815,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0169-7722(03)00032-9"},{"id":233039,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"66","issue":"3-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a5c1fe4b0c8380cd6fa59","contributors":{"authors":[{"text":"Kozak, J.A.","contributorId":50326,"corporation":false,"usgs":true,"family":"Kozak","given":"J.A.","email":"","affiliations":[],"preferred":false,"id":403145,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Reeves, H. W.","contributorId":53739,"corporation":false,"usgs":true,"family":"Reeves","given":"H.","email":"","middleInitial":"W.","affiliations":[],"preferred":false,"id":403146,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Lewis, B.A.","contributorId":66450,"corporation":false,"usgs":true,"family":"Lewis","given":"B.A.","email":"","affiliations":[],"preferred":false,"id":403147,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70024925,"text":"70024925 - 2003 - The typological approach to submarine groundwater discharge (SGD)","interactions":[],"lastModifiedDate":"2012-03-12T17:20:05","indexId":"70024925","displayToPublicDate":"2003-01-01T00:00:00","publicationYear":"2003","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1007,"text":"Biogeochemistry","active":true,"publicationSubtype":{"id":10}},"title":"The typological approach to submarine groundwater discharge (SGD)","docAbstract":"Coastal zone managers need to factor submarine groundwater discharge (SGD) in their integration. SGD provides a pathway for the transfer of freshwater, and its dissolved chemical burden, from the land to the coastal ocean. SGD reduces salinities and provides nutrients to specialized coastal habitats. It also can be a pollutant source, often undetected, causing eutrophication and triggering nuisance algal blooms. Despite its importance, SGD remains somewhat of a mystery in most places because it is usually unseen and difficult to measure. SGD has been directly measured at only about a hundred sites worldwide. A typology generated by the Land-Ocean Interaction in the Coastal Zone (LOICZ) Project is one of the few tools globally available to coastal resource managers for identifying areas in their jurisdiction where SGD may be a confounding process. (LOICZ is a core project of the International Geosphere/Biosphere Programme.) Of the hundreds of globally distributed parameters in the LOICZ typology, a SGD subset of potentially relevant parameters may be culled. A quantitative combination of the relevant hydrological parameters can serve as a proxy for the SGD conditions not directly measured. Web-LOICZ View, geospatial software then provides an automated approach to clustering these data into groups of locations that have similar characteristics. It permits selection of variables, of the number of clusters desired, and of the clustering criteria, and provides means of testing predictive results against independent variables. Information on the occurrence of a variety of SGD indicators can then be incorporated into regional clustering analysis. With such tools, coastal managers can focus attention on the most likely sites of SGD in their jurisdiction and design the necessary measurement and modeling programs needed for integrated management.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Biogeochemistry","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1023/B:BIOG.0000006125.10467.75","issn":"01682563","usgsCitation":"Bokuniewicz, H., Buddemeier, R., Maxwell, B., and Smith, C., 2003, The typological approach to submarine groundwater discharge (SGD): Biogeochemistry, v. 66, no. 1-2, p. 145-158, https://doi.org/10.1023/B:BIOG.0000006125.10467.75.","startPage":"145","endPage":"158","numberOfPages":"14","costCenters":[],"links":[{"id":207791,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1023/B:BIOG.0000006125.10467.75"},{"id":233005,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"66","issue":"1-2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505bb145e4b08c986b3252a2","contributors":{"authors":[{"text":"Bokuniewicz, H.","contributorId":68928,"corporation":false,"usgs":true,"family":"Bokuniewicz","given":"H.","email":"","affiliations":[],"preferred":false,"id":403142,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Buddemeier, R.","contributorId":84543,"corporation":false,"usgs":true,"family":"Buddemeier","given":"R.","affiliations":[],"preferred":false,"id":403143,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Maxwell, B.","contributorId":56615,"corporation":false,"usgs":true,"family":"Maxwell","given":"B.","email":"","affiliations":[],"preferred":false,"id":403141,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Smith, C.","contributorId":96429,"corporation":false,"usgs":true,"family":"Smith","given":"C.","affiliations":[],"preferred":false,"id":403144,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70024612,"text":"70024612 - 2003 - Vegetation, soil, and flooding relationships in a blackwater floodplain forest","interactions":[],"lastModifiedDate":"2012-03-12T17:20:06","indexId":"70024612","displayToPublicDate":"2003-01-01T00:00:00","publicationYear":"2003","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3750,"text":"Wetlands","onlineIssn":"1943-6246","printIssn":"0277-5212","active":true,"publicationSubtype":{"id":10}},"title":"Vegetation, soil, and flooding relationships in a blackwater floodplain forest","docAbstract":"Hydroperiod is considered the primary determinant of plant species distribution in temperate floodplain forests, but most studies have focused on alluvial (sediment-laden) river systems. Few studies have evaluated plant community relationships in blackwater river systems of the South Atlantic Coastal Plain of North America. In this study, we characterized the soils, hydroperiod, and vegetation communities and evaluated relationships between the physical and chemical environment and plant community structure on the floodplain of the Coosawhatchie River, a blackwater river in South Carolina, USA. The soils were similar to previous descriptions of blackwater floodplain soils but had greater soil N and P availability, substantially greater clay content, and lower soil silt content than was previously reported for other blackwater river floodplains. Results of a cluster analysis showed there were five forest communities on the site, and both short-term (4 years) and long-term (50 years) flooding records documented a flooding gradient: water tupelo community > swamp tupelo > laurel oak = overcup oak > mixed oak. The long-term hydrologic record showed that the floodplain has flooded less frequently from 1994 to present than in previous decades. Detrended correspondence analysis of environmental and relative basal area values showed that 27% of the variation in overstory community structure could be explained by the first two axes; however, fitting the species distributions to the DCA axes using Gaussian regression explained 67% of the variation. Axes were correlated with elevation (flooding intensity) and soil characteristics related to rooting volume and cation nutrient availability. Our study suggests that flooding is the major factor affecting community structure, but soil characteristics also may be factors in community structure in blackwater systems. ?? 2003, The Society of Wetland Scientists.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Wetlands","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","issn":"02775212","usgsCitation":"Burke, M., King, S., Gartner, D., and Eisenbies, M., 2003, Vegetation, soil, and flooding relationships in a blackwater floodplain forest: Wetlands, v. 23, no. 4, p. 988-1002.","startPage":"988","endPage":"1002","numberOfPages":"15","costCenters":[],"links":[{"id":233199,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"23","issue":"4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505bc1eae4b08c986b32a80a","contributors":{"authors":[{"text":"Burke, M.K.","contributorId":87248,"corporation":false,"usgs":true,"family":"Burke","given":"M.K.","email":"","affiliations":[],"preferred":false,"id":401905,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"King, S.L.","contributorId":105663,"corporation":false,"usgs":true,"family":"King","given":"S.L.","email":"","affiliations":[],"preferred":false,"id":401907,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Gartner, D.","contributorId":87249,"corporation":false,"usgs":true,"family":"Gartner","given":"D.","email":"","affiliations":[],"preferred":false,"id":401906,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Eisenbies, M.H.","contributorId":82420,"corporation":false,"usgs":true,"family":"Eisenbies","given":"M.H.","affiliations":[],"preferred":false,"id":401904,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ]}