We extend the finite-volume Eulerian-Lagrangian localized adjoint method (FVELLAM) for solution of the advection-dispersion equation to two dimensions. The method can conserve mass globally and is not limited by restrictions on the size of the grid Peclet or Courant number. Therefore, it is well suited for solution of advection-dominated ground-water solute transport problems. In test problem comparisons with standard finite differences, FVELLAM is able to attain accurate solutions on much coarser space and time grids. On fine grids, the accuracy of the two methods is comparable. A critical aspect of FVELLAM (and all other ELLAMs) is evaluation of the mass storage integral from the preceding time level. In FVELLAM this may be accomplished with either a forward or backtracking approach. The forward tracking approach conserves mass globally and is the preferred approach. The backtracking approach is less computationally intensive, but not globally mass conservative. Boundary terms are systematically represented as integrals in space and time which are evaluated by a common integration scheme in conjunction with forward tracking through time. Unlike the one-dimensional case, local mass conservation cannot be guaranteed, so slight oscillations in concentration can develop, particularly in the vicinity of inflow or outflow boundaries.
","language":"English","publisher":"Elsevier","doi":"10.1016/S0309-1708(96)00033-4","issn":"03091708","usgsCitation":"Healy, R.W., and Russell, T., 1998, Solution of the advection-dispersion equation in two dimensions by a finite-volume Eulerian-Lagrangian localized adjoint method: Advances in Water Resources, v. 21, no. 1, p. 11-26, https://doi.org/10.1016/S0309-1708(96)00033-4.","productDescription":"16 p.","startPage":"11","endPage":"26","numberOfPages":"16","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":230995,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"21","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b9258e4b08c986b319e6b","contributors":{"authors":[{"text":"Healy, Richard W. 0000-0002-0224-1858 rwhealy@usgs.gov","orcid":"https://orcid.org/0000-0002-0224-1858","contributorId":658,"corporation":false,"usgs":true,"family":"Healy","given":"Richard","email":"rwhealy@usgs.gov","middleInitial":"W.","affiliations":[{"id":5044,"text":"National Research Program - Central Branch","active":true,"usgs":true}],"preferred":true,"id":778906,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Russell, T.F.","contributorId":86811,"corporation":false,"usgs":true,"family":"Russell","given":"T.F.","email":"","affiliations":[],"preferred":false,"id":386986,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70020650,"text":"70020650 - 1998 - The hyporheic zone as a source of dissolved organic carbon and carbon gases to a temperate forested stream","interactions":[],"lastModifiedDate":"2019-02-01T06:41:34","indexId":"70020650","displayToPublicDate":"1998-01-01T00:00:00","publicationYear":"1998","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 hyporheic zone as a source of dissolved organic carbon and carbon gases to a temperate forested stream","docAbstract":"The objective of this study was to examine chemical changes in porewaters that occur over small scales (cm) as groundwater flows through the hyporheic zone and discharges to a stream in a temperate forest of northern Wisconsin. Hyporheic-zone porewaters were sampled at discrete depths of 2, 10, 15, 61, and 183 cm at three study sites in the study basin. Chemical profiles of dissolved organic carbon (DOC), CO2, CH4, and pH show dramatic changes between 61 cm sediment depth and the water-sediment interface. Unless discrete samples at small depth intervals are taken, these chemical profiles are not accounted for. Similar trends were observed at the three study locations, despite each site having very different hydraulic-flow regimes. Increases in DOC concentration by an order of magnitude from 61 to 15 cm depth with a corresponding decrease in pH and rapid decreases in the molecular weight of the DOC suggest that aliphatic compounds (likely organic acids) are being generated in the hyporheic zone. Estimated efflux rates of DOC, CO2, and CH4 to the stream are 6.2, 0.79, 0.13 moles m2 d-1, respectively, with the vast majority of these materials produced in the hyporheic zone. Very little of these materials are accounted for by sampling stream water, suggesting rapid uptake and/or volatilization.","language":"English","publisher":"Springer","doi":"10.1023/A:1006005311257","issn":"01682563","usgsCitation":"Schindler, J., and Krabbenhoft, D., 1998, The hyporheic zone as a source of dissolved organic carbon and carbon gases to a temperate forested stream: Biogeochemistry, v. 43, no. 2, p. 157-174, https://doi.org/10.1023/A:1006005311257.","productDescription":"18 p.","startPage":"157","endPage":"174","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":231075,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":206876,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1023/A:1006005311257"}],"volume":"43","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505bacd3e4b08c986b323781","contributors":{"authors":[{"text":"Schindler, J.E.","contributorId":14598,"corporation":false,"usgs":true,"family":"Schindler","given":"J.E.","email":"","affiliations":[],"preferred":false,"id":387009,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Krabbenhoft, D. P. 0000-0003-1964-5020","orcid":"https://orcid.org/0000-0003-1964-5020","contributorId":90765,"corporation":false,"usgs":true,"family":"Krabbenhoft","given":"D. P.","affiliations":[],"preferred":false,"id":387010,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70020652,"text":"70020652 - 1998 - Effects of arctic temperatures on distribution and retention of the nuclear waste radionuclides 241Am, 57Co, and 137Cs in the bioindicator bivalve Macoma balthica","interactions":[],"lastModifiedDate":"2020-01-05T18:10:32","indexId":"70020652","displayToPublicDate":"1998-01-01T00:00:00","publicationYear":"1998","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2664,"text":"Marine Environmental Research","active":true,"publicationSubtype":{"id":10}},"title":"Effects of arctic temperatures on distribution and retention of the nuclear waste radionuclides 241Am, 57Co, and 137Cs in the bioindicator bivalve Macoma balthica","docAbstract":"The disposal of radioactive wastes in Arctic seas has made it important to understand the processes affecting the accumulation of radionuclides in food webs in coldwater ecosystems. We examined the effects of temperature on radionuclide assimilation and retention by the bioindicator bivalve Macoma balthica using three representative nuclear waste components, 241Am, 57Co, and 137Cs. Experiments were designed to determine the kinetics of processes that control uptake from food and water, as well as kinetic constants of loss. 137Cs was not accumulated in soft tissue from water during short exposures, and was rapidly lost from shell with no thermal dependence. No effects of temperature on 57Co assimilation or retention from food were observed. The only substantial effect of polar temperatures was that on the assimilation efficiency of 241Am from food, where 10% was assimilated at 2 °C and 26% at 12 °C. For all three radionuclides, body distributions were correlated with source, with most radioactivity obtained from water found in the shell and food in the soft tissues. These results suggest that in general Arctic conditions had relatively small effects on the biological processes which influence the bioaccumulation of radioactive wastes, and bivalve concentration factors may not be appreciably different between polar and temperate waters.
Aqueous attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectra of 18 aliphatic di-carboxylic acids are reported as a function of pH. The spectra show isosbestic points and intensity changes which indicate that Beer's law is obeyed, and peak frequencies lie within previously reported ranges for aqueous carboxylates and pure carboxylic acids. Intensity sharing from the symmetric carboxylate stretch is evident in many cases, so that bands which are nominally due to alkyl groups show increased intensity at higher pH. The asymmetric stretch of the HA− species is linearly related to the microscopic acidity constantof the H2A species, with σpK<0.25 log units; this relationship falls on the same line as previously observed for mono-carboxylic acids. The linear relationship applies to the acidity constant of the HA− species only when the two acid groups are well separated (>2 intervening atoms). The results suggest that aqueous ATR-FTIR may be able to estimate `intrinsic' pKa values of carboxylic acids, in addition to providing quantitative estimates of ionization.
The impact on ground water quality from increasing fertilizer application rates over the past 40 years is evaluated within a glacial aquifer system beneath a thick unsaturated zone. Ground water ages within the aquifer could not be accurately determined from the measured distribution of 3H and as a result, chlorofluorocarbon (CFC) and 3H/3He dating techniques were applied. Beneath a 25 m thick unsaturated zone, ground water ages based on CFC‐11 concentrations were greater than 3H/3He ground water ages by 6 to 10 years, due to the time lag associated with the diffusion of CFCs through the unsaturated zone. Using the corrected CFC‐11 and 3H/3He ground water ages and the estimated travel time of 3H within the unsaturated zone, the approximate position of ground water recharged since the mid‐1960s was determined. Nitrate concentrations within post mid‐1960s recharge were generally elevated and near or above the drinking water limit of 10 mg‐N/L. In comparison, pre mid‐1960s recharge had nitrate concentrations <2.5 mg‐N/L. The elevated NO3− concentrations in post mid‐1960s recharge are attributed mainly to increasing fertilizer application rates between 1970 and the mid‐ to late 1980s. Anaerobic conditions suitable for denitrifkation are present within pre mid‐1960s recharge indicating that removal of DO is a slow process taking tens of years. Over the next 10 to 20 years, nitrate concentrations at municipal well fields that are currently capturing aerobic ground water recharged near the mid‐1960s are expected to increase because of the higher fertilizer application rates beginning in the 1970s and 1980s.
","language":"English","publisher":"Wiley","doi":"10.1111/j.1745-6584.1998.tb01078.x","issn":"0017467X","usgsCitation":"Johnston, C., Cook, P., Frape, S., Plummer, N., Busenberg, E., and Blackport, R., 1998, Ground water age and nitrate distribution within a glacial aquifer beneath a thick unsaturated zone: Groundwater, v. 36, no. 1, p. 171-180, https://doi.org/10.1111/j.1745-6584.1998.tb01078.x.","productDescription":"10 p.","startPage":"171","endPage":"180","costCenters":[{"id":436,"text":"National Research Program - Eastern Branch","active":true,"usgs":true},{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":230997,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"36","issue":"1","noUsgsAuthors":false,"publicationDate":"2005-08-04","publicationStatus":"PW","scienceBaseUri":"505a2aa2e4b0c8380cd5b332","contributors":{"authors":[{"text":"Johnston, C.T.","contributorId":100146,"corporation":false,"usgs":true,"family":"Johnston","given":"C.T.","email":"","affiliations":[],"preferred":false,"id":387101,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Cook, P.G.","contributorId":103807,"corporation":false,"usgs":true,"family":"Cook","given":"P.G.","email":"","affiliations":[],"preferred":false,"id":387103,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Frape, S.K.","contributorId":105335,"corporation":false,"usgs":true,"family":"Frape","given":"S.K.","affiliations":[],"preferred":false,"id":387104,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Plummer, Niel 0000-0002-4020-1013 nplummer@usgs.gov","orcid":"https://orcid.org/0000-0002-4020-1013","contributorId":190100,"corporation":false,"usgs":true,"family":"Plummer","given":"Niel","email":"nplummer@usgs.gov","affiliations":[{"id":436,"text":"National Research Program - Eastern Branch","active":true,"usgs":true}],"preferred":true,"id":387100,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Busenberg, Eurybiades ebusenbe@usgs.gov","contributorId":2271,"corporation":false,"usgs":true,"family":"Busenberg","given":"Eurybiades","email":"ebusenbe@usgs.gov","affiliations":[{"id":436,"text":"National Research Program - Eastern Branch","active":true,"usgs":true}],"preferred":true,"id":387099,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Blackport, R.J.","contributorId":100573,"corporation":false,"usgs":true,"family":"Blackport","given":"R.J.","email":"","affiliations":[],"preferred":false,"id":387102,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}} ,{"id":70020690,"text":"70020690 - 1998 - System controls on the aqueous distribution of mercury in the northern Florida Everglades","interactions":[],"lastModifiedDate":"2019-02-01T06:58:12","indexId":"70020690","displayToPublicDate":"1998-01-01T00:00:00","publicationYear":"1998","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1007,"text":"Biogeochemistry","active":true,"publicationSubtype":{"id":10}},"title":"System controls on the aqueous distribution of mercury in the northern Florida Everglades","docAbstract":"The forms and partitioning of aqueous mercury species in the canals and marshes of the Northern Florida Everglades exhibit strong spatial and temporal variability. In canals feeding Water Conservation Area (WCA) 2A, unfiltered total Hg (HgT(U)) is less than 3 ng L-1 and relatively constant. In contrast, methyl mercury (MeHg) exhibited a strong seasonal pattern, with highest levels entering WCA-2A marshes during July. Stagnation and reduced flows also lead to particle enrichment of MeHg. In the marshes of WCA-2A, 2B and 3A, HgT(U) is usually <5 ng L-1 with no consistent north-south patterns. However, for individual dates, aqueous unfiltered MeHg (MeHg(U)) levels increase from north to south with generally lowest levels in the eutrophied regions of northern WCA-2A. A strong relationship between filtered Hg species and dissolved organic carbon (DOC), evident for rivers draining wetlands in Wisconsin, was not apparent in the Everglades, suggesting either differences in the binding sites of DOC between the two regions, or non-organic Hg complexation in the Everglades.","language":"English","publisher":"Springer","doi":"10.1023/A:1005928927272","issn":"01682563","usgsCitation":"Hurley, J., Krabbenhoft, D., Cleckner, L., Olson, M., Aiken, G., and Rawlik, P., 1998, System controls on the aqueous distribution of mercury in the northern Florida Everglades: Biogeochemistry, v. 40, no. 2-3, p. 293-311, https://doi.org/10.1023/A:1005928927272.","productDescription":"19 p.","startPage":"293","endPage":"311","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":231194,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"40","issue":"2-3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505ba366e4b08c986b31fcb5","contributors":{"authors":[{"text":"Hurley, J.P.","contributorId":97645,"corporation":false,"usgs":true,"family":"Hurley","given":"J.P.","email":"","affiliations":[],"preferred":false,"id":387155,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Krabbenhoft, D. P. 0000-0003-1964-5020","orcid":"https://orcid.org/0000-0003-1964-5020","contributorId":90765,"corporation":false,"usgs":true,"family":"Krabbenhoft","given":"D. P.","affiliations":[],"preferred":false,"id":387154,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Cleckner, L.B.","contributorId":29966,"corporation":false,"usgs":true,"family":"Cleckner","given":"L.B.","email":"","affiliations":[],"preferred":false,"id":387153,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Olson, M.L.","contributorId":21989,"corporation":false,"usgs":true,"family":"Olson","given":"M.L.","email":"","affiliations":[],"preferred":false,"id":387152,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Aiken, G. R. 0000-0001-8454-0984","orcid":"https://orcid.org/0000-0001-8454-0984","contributorId":14452,"corporation":false,"usgs":true,"family":"Aiken","given":"G. R.","affiliations":[],"preferred":false,"id":387150,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Rawlik, P.S. Jr.","contributorId":19329,"corporation":false,"usgs":true,"family":"Rawlik","given":"P.S.","suffix":"Jr.","affiliations":[],"preferred":false,"id":387151,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}} ,{"id":70020693,"text":"70020693 - 1998 - A comparison of zero-order, first-order, and monod biotransformation models","interactions":[],"lastModifiedDate":"2018-12-21T07:43:38","indexId":"70020693","displayToPublicDate":"1998-01-01T00:00:00","publicationYear":"1998","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1861,"text":"Ground Water","active":true,"publicationSubtype":{"id":10}},"title":"A comparison of zero-order, first-order, and monod biotransformation models","docAbstract":"Under some conditions, a first-order kinetic model is a poor representation of biodegradation in contaminated aquifers. Although it is well known that the assumption of first-order kinetics is valid only when substrate concentration, S, is much less than the half-saturation constant, K(s), this assumption is often made without verification of this condition. We present a formal error analysis showing that the relative error in the first-order approximation is S/K(S) and in the zero-order approximation the error is K(s)/S. We then examine the problems that arise when the first-order approximation is used outside the range for which it is valid. A series of numerical simulations comparing results of first- and zero-order rate approximations to Monod kinetics for a real data set illustrates that if concentrations observed in the field are higher than K(s), it may better to model degradation using a zero-order rate expression. Compared with Monod kinetics, extrapolation of a first-order rate to lower concentrations under-predicts the biotransformation potential, while extrapolation to higher concentrations may grossly over-predict the transformation rate. A summary of solubilities and Monod parameters for aerobic benzene, toluene, and xylene (BTX) degradation shows that the a priori assumption of first-order degradation kinetics at sites contaminated with these compounds is not valid. In particular, out of six published values of KS for toluene, only one is greater than 2 mg/L, indicating that when toluene is present in concentrations greater than about a part per million, the assumption of first-order kinetics may be invalid. Finally, we apply an existing analytical solution for steady-state one-dimensional advective transport with Monod degradation kinetics to a field data set.A formal error analysis is presented showing that the relative error in the first-order approximation is S/KS and in the zero-order approximation the error is KS/S where S is the substrate concentration and KS is the half-saturation constant. The problems that arise when the first-order approximation is used outside the range for which it is valid are examined. A series of numerical simulations comparing results of first- and zero-order rate approximations to Monod kinetics for a real data set illustrates that if concentrations observed in the field are higher than KS, it may be better to model degradation using a zero-order rate expression.","language":"English","publisher":"Wiley","doi":"10.1111/j.1745-6584.1998.tb01091.x","issn":"0017467X","usgsCitation":"Bekins, B., Warren, E., and Godsy, E., 1998, A comparison of zero-order, first-order, and monod biotransformation models: Ground Water, v. 36, no. 2, p. 261-268, https://doi.org/10.1111/j.1745-6584.1998.tb01091.x.","productDescription":"8 p.","startPage":"261","endPage":"268","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":231235,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"36","issue":"2","noUsgsAuthors":false,"publicationDate":"2005-08-04","publicationStatus":"PW","scienceBaseUri":"5059e37ce4b0c8380cd46075","contributors":{"authors":[{"text":"Bekins, B.A.","contributorId":98309,"corporation":false,"usgs":true,"family":"Bekins","given":"B.A.","email":"","affiliations":[],"preferred":false,"id":387165,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Warren, E.","contributorId":15360,"corporation":false,"usgs":true,"family":"Warren","given":"E.","email":"","affiliations":[],"preferred":false,"id":387163,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Godsy, E.M.","contributorId":56685,"corporation":false,"usgs":true,"family":"Godsy","given":"E.M.","email":"","affiliations":[],"preferred":false,"id":387164,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70020697,"text":"70020697 - 1998 - Multi-level slug tests in highly permeable formations: 2. Hydraulic conductivity identification, method verification, and field applications","interactions":[],"lastModifiedDate":"2012-03-12T17:20:18","indexId":"70020697","displayToPublicDate":"1998-01-01T00:00:00","publicationYear":"1998","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2342,"text":"Journal of Hydrology","active":true,"publicationSubtype":{"id":10}},"title":"Multi-level slug tests in highly permeable formations: 2. Hydraulic conductivity identification, method verification, and field applications","docAbstract":"Using the developed theory and modified Springer-Gelhar (SG) model, an identification method is proposed for estimating hydraulic conductivity from multi-level slug tests. The computerized algorithm calculates hydraulic conductivity from both monotonic and oscillatory well responses obtained using a double-packer system. Field verification of the method was performed at a specially designed fully penetrating well of 0.1-m diameter with a 10-m screen in a sand and gravel alluvial aquifer (MSEA site, Shelton, Nebraska). During well installation, disturbed core samples were collected every 0.6 m using a split-spoon sampler. Vertical profiles of hydraulic conductivity were produced on the basis of grain-size analysis of the disturbed core samples. These results closely correlate with the vertical profile of horizontal hydraulic conductivity obtained by interpreting multi-level slug test responses using the modified SG model. The identification method was applied to interpret the response from 474 slug tests in 156 locations at the MSEA site. More than 60% of responses were oscillatory. The method produced a good match to experimental data for both oscillatory and monotonic responses using an automated curve matching procedure. The proposed method allowed us to drastically increase the efficiency of each well used for aquifer characterization and to process massive arrays of field data. Recommendations generalizing this experience to massive application of the proposed method are developed.Using the developed theory and modified Springer-Gelhar (SG) model, an identification method is proposed for estimating hydraulic conductivity from multi-level slug tests. The computerized algorithm calculates hydraulic conductivity from both monotonic and oscillatory well responses obtained using a double-packer system. Field verification of the method was performed at a specially designed fully penetrating well of 0.1-m diameter with a 10-m screen in a sand and gravel alluvial aquifer (MSEA site, Shelton, Nebraska). During well installation, disturbed core samples were collected every 0.6 m using a split-spoon sampler. Vertical profiles of hydraulic conductivity were produced on the basis of grain-size analysis of the disturbed core samples. These results closely correlate with the vertical profile of horizontal hydraulic conductivity obtained by interpreting multi-level slug test responses using the modified SG model. The identification method was applied to interpret the response from 474 slug tests in 156 locations at the MSEA site. More than 60% of responses were oscillatory. The method produced a good match to experimental data for both oscillatory and monotonic responses using an automated curve matching procedure. The proposed method allowed us to drastically increase the efficiency of each well used for aquifer characterization and to process massive arrays of field data. Recommendations generalizing this experience to massive application of the proposed method are developed.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Hydrology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"Elsevier Sci B.V.","publisherLocation":"Amsterdam, Netherlands","doi":"10.1016/S0022-1694(97)00127-3","issn":"00221694","usgsCitation":"Zlotnik, V., and McGuire, V., 1998, Multi-level slug tests in highly permeable formations: 2. Hydraulic conductivity identification, method verification, and field applications: Journal of Hydrology, v. 204, no. 1-4, p. 283-296, https://doi.org/10.1016/S0022-1694(97)00127-3.","startPage":"283","endPage":"296","numberOfPages":"14","costCenters":[],"links":[{"id":231313,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":206944,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0022-1694(97)00127-3"}],"volume":"204","issue":"1-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a5fb7e4b0c8380cd710c1","contributors":{"authors":[{"text":"Zlotnik, V.A.","contributorId":102660,"corporation":false,"usgs":true,"family":"Zlotnik","given":"V.A.","email":"","affiliations":[],"preferred":false,"id":387174,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"McGuire, V. L. 0000-0002-3962-4158","orcid":"https://orcid.org/0000-0002-3962-4158","contributorId":94702,"corporation":false,"usgs":true,"family":"McGuire","given":"V. L.","affiliations":[],"preferred":false,"id":387173,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70020698,"text":"70020698 - 1998 - The use of synthesized aqueous solutions for determining strontium sorption isotherms","interactions":[],"lastModifiedDate":"2012-03-12T17:20:18","indexId":"70020698","displayToPublicDate":"1998-01-01T00:00:00","publicationYear":"1998","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":"The use of synthesized aqueous solutions for determining strontium sorption isotherms","docAbstract":"The use of synthesized aqueous solutions for determining experimentally derived strontium sorption isotherms of sediment was investigated as part of a study accessing strontium chemical transport properties. Batch experimental techniques were used to determine strontium sorption isotherms using synthesized aqueous solutions designed to chemically represent water from a natural aquifer with respect to major ionic character and pH. A strontium sorption isotherm for a sediment derived using a synthesized aqueous solution was found to be most comparable to an isotherm derived using natural water when the synthesized aqueous solution contained similar concentrations of calcium and magnesium. However, it is difficult to match compositions exactly due to the effects of disequilibrium between the solution and the sediment. Strong linear relations between sorbed strontium and solution concentrations of calcium and magnesium confirm that these cations are important co-constituents in these synthesized aqueous solutions. Conversely, weak linear relations between sorbed strontium and solution concentrations of sodium and potassium indicate that these constituents do not affect sorption of strontium. The addition of silica to the synthesized aqueous solution does not appreciably affect the resulting strontium sorption isotherm.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Contaminant Hydrology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0169-7722(96)00098-8","issn":"01697722","usgsCitation":"Liszewski, M.J., Bunde, R., Hemming, C., Rosentreter, J., and Welhan, J., 1998, The use of synthesized aqueous solutions for determining strontium sorption isotherms: Journal of Contaminant Hydrology, v. 29, no. 2, p. 93-108, https://doi.org/10.1016/S0169-7722(96)00098-8.","startPage":"93","endPage":"108","numberOfPages":"16","costCenters":[],"links":[{"id":206956,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0169-7722(96)00098-8"},{"id":231348,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"29","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505bb19ce4b08c986b325368","contributors":{"authors":[{"text":"Liszewski, M. J.","contributorId":107308,"corporation":false,"usgs":true,"family":"Liszewski","given":"M.","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":387179,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Bunde, R.L.","contributorId":35885,"corporation":false,"usgs":true,"family":"Bunde","given":"R.L.","email":"","affiliations":[],"preferred":false,"id":387177,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Hemming, C.","contributorId":87326,"corporation":false,"usgs":true,"family":"Hemming","given":"C.","email":"","affiliations":[],"preferred":false,"id":387178,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Rosentreter, J.","contributorId":25727,"corporation":false,"usgs":true,"family":"Rosentreter","given":"J.","email":"","affiliations":[],"preferred":false,"id":387176,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Welhan, J.","contributorId":14127,"corporation":false,"usgs":true,"family":"Welhan","given":"J.","email":"","affiliations":[],"preferred":false,"id":387175,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":70020724,"text":"70020724 - 1998 - Contribution of hydroxylated atrazine degradation products to the total atrazine load in midwestern streams","interactions":[],"lastModifiedDate":"2019-02-04T10:12:13","indexId":"70020724","displayToPublicDate":"1998-01-01T00:00:00","publicationYear":"1998","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":"Contribution of hydroxylated atrazine degradation products to the total atrazine load in midwestern streams","docAbstract":"The contribution of hydroxylated atrazine degradation products (HADPs) to the total atrazine load (i.e., atrazine plus stable metabolites) in streams needs to be determined in order to fully assess the impact of atrazine contamination on stream ecosystems and human health. The objectives of this study were (1) to determine the contribution of HADPs to the total atrazine load in streams of nine midwestern states and (2) to discuss the mechanisms controlling the concentrations of HADPs in streams. Stream samples were collected from 95 streams in northern Missouri at preplant and postplant of 1994 and 1995, and an additional 46 streams were sampled in eight midwestern states at postplant of 1995. Samples were analyzed for atrazine, deethylatrazine (DEA), deisopropylatrazine (DIA), and three HADPs. Overall, HADP prevalence (i.e., frequency of detection) ranged from 87 to 100% for hydroxyatrazine (HA), 0 to 58% for deethylhydroxyatrazine (DEHA), and 0% for deisopropylhydroxyatrazine (DIHA) with method detection limits of 0.04−0.10 μg L-1. Atrazine metabolites accounted for nearly 60% of the atrazine load in northern Missouri streams at preplant, with HA the predominant metabolite present. Data presented in this study and a continuous monitoring study are used to support the hypothesis that a combination of desorption from stream sediments and dissolved-phase transport control HADP concentrations in streams.
ABSTRACT: A hydrologic modeling study, using the Hydrologic Simulation Program - FORTRAN (HSPF), was conducted in two glaciated watersheds, Purdy Creek and Ariel Creek in northeastern Pennsylvania. Both watersheds have wetlands and poorly drained soils due to low hydraulic conductivity and presence of fragipans. The HSPF model was calibrated in the Purdy Creek watershed and verified in the Ariel Creek watershed for June 1992 to December 1993 period. In Purdy Creek, the total volume of observed stream-flow during the entire simulation period was 13.36 × 106 m3 and the simulated streamflow volume was 13.82 × 106 m3 (5 percent difference). For the verification simulation in Ariel Creek, the difference between the total observed and simulated flow volumes was 17 percent. Simulated peak flow discharges were within two hours of the observed for 30 of 46 peak flow events (discharge greater than 0.1 m3/sec) in Purdy Creek and 27 of 53 events in Ariel Creek. For 22 of the 46 events in Purdy Creek and 24 of 53 in Ariel Creek, the differences between the observed and simulated peak discharge rates were less than 30 percent. These 22 events accounted for 63 percent of total volume of streamflow observed during the selected 46 peak flow events in Purdy Creek. In Ariel Creek, these 24 peak flow events accounted for 62 percent of the total flow observed during all peak flow events. Differences in observed and simulated peak flow rates and volumes (on a percent basis) were greater during the snowmelt runoff events and summer periods than for other times.
Arsenic concentrations in ground water of the lower Madison River valley, Montana, are high (16 to 176 μg/L). Previous studies hypothesized that arsenic-rich river water, applied as irrigation, was evapoconcentrated during recharge and contaminated the thin alluvial aquifer. Based on additional data collection and a reevaluation of the hydrology and geochemistry of the valley, the high arsenic concentrations in ground water are caused by a unique combination of natural hydrologic and geochemical factors, and irrigation appears to play a secondary role. The high arsenic concentrations in ground water have several causes: direct aquifer recharge by Madison River water having arsenic concentrations as high as 100 μg/L, leaching of arsenic from Tertiary volcano-clastic sediment, and release of sorbed arsenic where redox conditions in ground water are reduced. The findings are consistent with related studies that demonstrate that arsenic is sorbed by irrigated soils in the valley. Although evaporation of applied irrigation water does not significantly increase arsenic concentrations in ground water, irrigation with arsenic-rich water raises other environmental concerns.
Anaerobic oxidation of [1,2-14C]vinyl chloride and [1,2-14C]dichloroethene to 14CO2under humic acid-reducing conditions was demonstrated. The results indicate that waterborne contaminants can be oxidized by using humic acid compounds as electron acceptors and suggest that natural aquatic systems have a much larger capacity for contaminant oxidation than previously thought.
","language":"English","publisher":"American Society for Microbiology","doi":"10.1128/AEM.64.8.3102-3105.1998","issn":"00992240","usgsCitation":"Bradley, P., Chapelle, F.H., and Lovley, D.R., 1998, Humic acids as electron acceptors for anaerobic microbial oxidation of vinyl chloride and dichloroethene: Applied and Environmental Microbiology, v. 64, no. 8, p. 3102-3105, https://doi.org/10.1128/AEM.64.8.3102-3105.1998.","productDescription":"4 p.","startPage":"3102","endPage":"3105","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":479730,"rank":2,"type":{"id":41,"text":"Open Access External Repository Page"},"url":"https://doi.org/10.1128/aem.64.8.3102-3105.1998","text":"External Repository"},{"id":231005,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"64","issue":"8","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a3289e4b0c8380cd5e8aa","contributors":{"authors":[{"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":387549,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Chapelle, F. H.","contributorId":101697,"corporation":false,"usgs":true,"family":"Chapelle","given":"F.","email":"","middleInitial":"H.","affiliations":[],"preferred":false,"id":387550,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Lovley, Derek R.","contributorId":107852,"corporation":false,"usgs":true,"family":"Lovley","given":"Derek","middleInitial":"R.","affiliations":[],"preferred":false,"id":387551,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70020796,"text":"70020796 - 1998 - Characterizing a ground water basin in a New England mountain and valley terrain","interactions":[],"lastModifiedDate":"2019-03-29T09:21:14","indexId":"70020796","displayToPublicDate":"1998-01-01T00:00:00","publicationYear":"1998","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3825,"text":"Groundwater","active":true,"publicationSubtype":{"id":10}},"title":"Characterizing a ground water basin in a New England mountain and valley terrain","docAbstract":"A ground water basin is defined as the volume of subsurface through which ground water flows from the water table to a specified discharge location. Delineating the topographically defined surface water basin and extending it vertically downward does not always define the ground water basin. Instead, a ground water basin is more appropriately delineated by tracking ground water flowpaths with a calibrated, three‐dimensional ground water flow model. To determine hydrologic and chemical budgets of the basin, it is also necessary to quantify flow through each hydrogeologic unit in the basin. In particular, partitioning ground water flow through unconsolidated deposits versus bedrock is of significant interest to hillslope hydrologic studies. To address these issues, a model is developed and calibrated to simulate ground water flow through glacial deposits and fractured crystalline bedrock in the vicinity of Mirror Lake, New Hampshire. Tracking of ground water flowpaths suggests that Mirror Lake and its inlet streams drain a ground water recharge area that is about 1.5 times the area of the surface water basin. Calculation of the ground water budget suggests that, of the recharge that enters the Mirror Lake ground water basin, about 40% travels through the basin along flowpaths that stay exclusively in the glacial deposits, and about 60% travels along flowpaths that involve movement in bedrock.
","language":"English","publisher":"NGWA","doi":"10.1111/j.1745-6584.1998.tb02835.x","issn":"0017467X","usgsCitation":"Tiedeman, C.R., Goode, D., and Hsieh, P.A., 1998, Characterizing a ground water basin in a New England mountain and valley terrain: Groundwater, v. 36, no. 4, p. 611-620, https://doi.org/10.1111/j.1745-6584.1998.tb02835.x.","productDescription":"10 p.","startPage":"611","endPage":"620","costCenters":[{"id":532,"text":"Pennsylvania Water Science Center","active":true,"usgs":true},{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":231082,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"New Hampshire","otherGeospatial":"Mirror Lake","volume":"36","issue":"4","noUsgsAuthors":false,"publicationDate":"2005-12-23","publicationStatus":"PW","scienceBaseUri":"5059f4ede4b0c8380cd4bfee","contributors":{"authors":[{"text":"Tiedeman, Claire R. 0000-0002-0128-3685 tiedeman@usgs.gov","orcid":"https://orcid.org/0000-0002-0128-3685","contributorId":196777,"corporation":false,"usgs":true,"family":"Tiedeman","given":"Claire","email":"tiedeman@usgs.gov","middleInitial":"R.","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":387556,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Goode, Daniel J. 0000-0002-8527-2456 djgoode@usgs.gov","orcid":"https://orcid.org/0000-0002-8527-2456","contributorId":2433,"corporation":false,"usgs":true,"family":"Goode","given":"Daniel J.","email":"djgoode@usgs.gov","affiliations":[{"id":532,"text":"Pennsylvania Water Science Center","active":true,"usgs":true}],"preferred":false,"id":649679,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Hsieh, Paul A. 0000-0003-4873-4874 pahsieh@usgs.gov","orcid":"https://orcid.org/0000-0003-4873-4874","contributorId":1634,"corporation":false,"usgs":true,"family":"Hsieh","given":"Paul","email":"pahsieh@usgs.gov","middleInitial":"A.","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},{"id":39113,"text":"WMA - Office of Quality Assurance","active":true,"usgs":true}],"preferred":true,"id":649680,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70020801,"text":"70020801 - 1998 - Application of the top specified boundary layer (TSBL) approximation to initial characterization of an inland aquifer mineralization: 2. Seepage of saltwater through semi-confining layers","interactions":[],"lastModifiedDate":"2012-03-12T17:19:52","indexId":"70020801","displayToPublicDate":"1998-01-01T00:00:00","publicationYear":"1998","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":"Application of the top specified boundary layer (TSBL) approximation to initial characterization of an inland aquifer mineralization: 2. Seepage of saltwater through semi-confining layers","docAbstract":"This paper presents a generalized basic study that addresses practical needs for an understanding of the major mechanisms involved in the mineralization of groundwater in the Great Bend Prairie aquifer in south- central Kansas. This Quaternary alluvial aquifer and associated surface waters are subject to contamination by saltwater, which in some areas seeps from the deeper Permian bedrock formation into the overlying freshwater aquifer through semiconfining layers. A simplified conceptual model is adopted. It incorporates the freshwater aquifer whose bottom is comprised of a semiconfining layer through which a hydrologically minor but geochemically important saline water discharge seeps into the aquifer. A hierarchy of approximate approaches is considered to analyze the mineralization processes taking place in the aquifer. The recently developed top specified boundary layer (TSBL) approach is very convenient to use for the initial characterization of these processes, and is further adapted to characterization of head-driven seepage through semi-confining layers. TSBL calculations indicate that the seeping saline water may create two distinct new zones in the aquifer: (1) a completely saline zone (CSZ) adjacent to the semiconfining bottom of the aquifer, and (2) a transition zone (TZ) which develops between the CSZ and the freshwater zone. Some possible scenarios associated with the various mineralization patterns are analyzed and discussed.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Contaminant Hydrology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0169-7722(98)00055-2","issn":"01697722","usgsCitation":"Rubin, H., and Buddemeier, R., 1998, Application of the top specified boundary layer (TSBL) approximation to initial characterization of an inland aquifer mineralization: 2. Seepage of saltwater through semi-confining layers: Journal of Contaminant Hydrology, v. 32, no. 3-4, p. 377-402, https://doi.org/10.1016/S0169-7722(98)00055-2.","startPage":"377","endPage":"402","numberOfPages":"26","costCenters":[],"links":[{"id":229914,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":206476,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0169-7722(98)00055-2"}],"volume":"32","issue":"3-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059ecbbe4b0c8380cd49458","contributors":{"authors":[{"text":"Rubin, H.","contributorId":54358,"corporation":false,"usgs":true,"family":"Rubin","given":"H.","email":"","affiliations":[],"preferred":false,"id":387579,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Buddemeier, R. W.","contributorId":86492,"corporation":false,"usgs":true,"family":"Buddemeier","given":"R. W.","affiliations":[],"preferred":false,"id":387580,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70020816,"text":"70020816 - 1998 - Determining rates of chemical weathering in soils - Solute transport versus profile evolution","interactions":[],"lastModifiedDate":"2018-01-30T19:27:36","indexId":"70020816","displayToPublicDate":"1998-01-01T00:00:00","publicationYear":"1998","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2342,"text":"Journal of Hydrology","active":true,"publicationSubtype":{"id":10}},"title":"Determining rates of chemical weathering in soils - Solute transport versus profile evolution","docAbstract":"SiO2 fluxes associated with contemporary solute transport in three deeply weathered granitoid profiles are compared to bulk SiO2 losses that have occurred during regolith development. Climates at the three profiles range from Mediterranean to humid to tropical. Due to shallow impeding alluvial layers at two of the profiles, and seasonally uniform rainfall at the third, temporal variations in hydraulic and chemical state variables are largely attenuated below depths of 1-2 m. This allows current SiO2 fluxes below the zone of seasonal variations to be estimated from pore-water concentrations and average hydraulic flux densities. Mean-annual SiO2 concentrations were 0.1-1.5 mM. Hydraulic conductivities for the investigated range of soil-moisture saturations ranged from < 10-9 to > 10-6 m s-1. Estimated hydraulic flux densities for quasi-steady portions of the profiles varied from 6 x 10-9 to 14 x 10-9 m s-1 based on Darcy's law and field measurements of moisture saturations and pressure heads. Corresponding fluid-residence times in the profiles ranged from 10 to 44 years. Total SiO2 losses, based on chemical and volumetric changes in the respective profiles, ranged from 19 to 110 kmoles SiO2 m-2 of land surface as a result of 0.2-0.4 Ma of chemical weathering. Extrapolation of contemporary solute fluxes to comparable time periods reproduced these SiO2 losses to about an order of magnitude. Despite the large range and non-linearity of measured hydraulic conductivities, solute transport rates in weathering regoliths can be estimated from characterization of hydrologic conditions at sufficiently large depths. The agreement suggests that current weathering rates are representative of long-term average weathering rates in the regoliths.SiO2 fluxes associated with contemporary solute transport in three deeply weathered granitoid profiles are compared to bulk SiO2 losses during regolith development. Due to shallow impeding alluvial layers at two of the profiles, and seasonally uniform rainfall at the third, temporal variations in hydraulic and chemical state variables are largely attenuated below depths of 1-2 m. Hydraulic conductivities for the investigated range of soil-moisture saturations of <10-9 to >10-6 m/s-1. Estimated hydraulic flux densities for quasi-steady portions of the profiles varied from 6??10-9 to 14??10-9 m/s based on Darcy's law and field measurements of moisture saturations and pressure heads.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Hydrology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"Elsevier Sci B.V.","publisherLocation":"Amsterdam, Netherlands","doi":"10.1016/S0022-1694(98)00158-9","issn":"00221694","usgsCitation":"Stonestrom, D.A., White, A.F., and Akstin, K., 1998, Determining rates of chemical weathering in soils - Solute transport versus profile evolution: Journal of Hydrology, v. 209, no. 1-4, p. 331-345, https://doi.org/10.1016/S0022-1694(98)00158-9.","startPage":"331","endPage":"345","numberOfPages":"15","costCenters":[],"links":[{"id":206538,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0022-1694(98)00158-9"},{"id":230155,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"209","issue":"1-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059fff3e4b0c8380cd4f4c2","contributors":{"authors":[{"text":"Stonestrom, David A. 0000-0001-7883-3385 dastones@usgs.gov","orcid":"https://orcid.org/0000-0001-7883-3385","contributorId":2280,"corporation":false,"usgs":true,"family":"Stonestrom","given":"David","email":"dastones@usgs.gov","middleInitial":"A.","affiliations":[{"id":438,"text":"National Research Program - Western Branch","active":true,"usgs":true}],"preferred":true,"id":387640,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"White, A. F.","contributorId":36546,"corporation":false,"usgs":true,"family":"White","given":"A.","email":"","middleInitial":"F.","affiliations":[],"preferred":false,"id":387639,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Akstin, K.C.","contributorId":105445,"corporation":false,"usgs":true,"family":"Akstin","given":"K.C.","affiliations":[],"preferred":false,"id":387641,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70020819,"text":"70020819 - 1998 - Effect of groundwater springs on NO3− concentrations during summer in Catskill Mountain streams","interactions":[],"lastModifiedDate":"2018-03-16T10:01:07","indexId":"70020819","displayToPublicDate":"1998-01-01T00:00:00","publicationYear":"1998","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3722,"text":"Water Resources Research","onlineIssn":"1944-7973","printIssn":"0043-1397","active":true,"publicationSubtype":{"id":10}},"displayTitle":"Effect of groundwater springs on NO3− concentrations during summer in Catskill Mountain streams","title":"Effect of groundwater springs on NO3− concentrations during summer in Catskill Mountain streams","docAbstract":"Groundwater and stream water data collected at three headwater catchments in the Neversink River watershed indicate that base flow is sustained by groundwater from two sources: a shallow flow system within the till and soil and a deep flow system within bedrock fractures and bedding planes that discharges as perennial springs. Data from eight wells finished near the till/bedrock interface indicate that saturated conditions are not maintained in the shallow flow system during most summers. In contrast, the discharge of a perennial spring remained constant during two summer rainstorms, providing evidence that the deep flow system is disconnected from the shallow flow system in summer. Discharge from perennial springs was the principal source of streamflow in a headwater reach during low flow. Mean NO3− concentrations were 20–25 μmol L−1 in five perennial springs during the summer but only 5–10 μmol L−1 in shallow groundwater. Thus the deep flow system does not reflect typical NO3− concentrations in the soil during summer. A hydrologic budget at a headwater drainage reveals that March and late fall are the principal groundwater recharge periods. Residence time modeling based on analyses of 18O and 35S indicates that groundwater in the deep flow system is 6–22 months old. These data indicate that summer base flow largely originates from previous dormant seasons when available soil NO3− is greater. In these Catskill watersheds, high base flow concentrations of NO3− during summer do not provide sufficient evidence that the atmospheric N deposition rate exceeds the demand of terrestrial vegetation.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/98WR01282","usgsCitation":"Burns, D.A., Murdoch, P.S., Lawrence, G.B., and Michel, R.L., 1998, Effect of groundwater springs on NO3− concentrations during summer in Catskill Mountain streams: Water Resources Research, v. 34, no. 8, p. 1987-1996, https://doi.org/10.1029/98WR01282.","productDescription":"10 p.","startPage":"1987","endPage":"1996","costCenters":[],"links":[{"id":487361,"rank":1,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/98wr01282","text":"Publisher Index Page"},{"id":230195,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","volume":"34","issue":"8","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a05e6e4b0c8380cd50ff8","contributors":{"authors":[{"text":"Burns, Douglas A. 0000-0001-6516-2869 daburns@usgs.gov","orcid":"https://orcid.org/0000-0001-6516-2869","contributorId":1237,"corporation":false,"usgs":true,"family":"Burns","given":"Douglas","email":"daburns@usgs.gov","middleInitial":"A.","affiliations":[{"id":474,"text":"New York Water Science Center","active":true,"usgs":true}],"preferred":true,"id":387650,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Murdoch, Peter S. 0000-0001-9243-505X pmurdoch@usgs.gov","orcid":"https://orcid.org/0000-0001-9243-505X","contributorId":2453,"corporation":false,"usgs":true,"family":"Murdoch","given":"Peter","email":"pmurdoch@usgs.gov","middleInitial":"S.","affiliations":[{"id":5067,"text":"Northeast Regional Director's Office","active":true,"usgs":true}],"preferred":true,"id":387651,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Lawrence, Gregory B. 0000-0002-8035-2350 glawrenc@usgs.gov","orcid":"https://orcid.org/0000-0002-8035-2350","contributorId":867,"corporation":false,"usgs":true,"family":"Lawrence","given":"Gregory","email":"glawrenc@usgs.gov","middleInitial":"B.","affiliations":[{"id":474,"text":"New York Water Science Center","active":true,"usgs":true}],"preferred":true,"id":387652,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Michel, Robert L. rlmichel@usgs.gov","contributorId":823,"corporation":false,"usgs":true,"family":"Michel","given":"Robert","email":"rlmichel@usgs.gov","middleInitial":"L.","affiliations":[{"id":148,"text":"Branch of Regional Research-Western Region","active":false,"usgs":true}],"preferred":true,"id":387653,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70020829,"text":"70020829 - 1998 - Modeling CO2 degassing and pH in a stream-aquifer system","interactions":[],"lastModifiedDate":"2018-09-10T09:48:58","indexId":"70020829","displayToPublicDate":"1998-01-01T00:00:00","publicationYear":"1998","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2342,"text":"Journal of Hydrology","active":true,"publicationSubtype":{"id":10}},"title":"Modeling CO2 degassing and pH in a stream-aquifer system","docAbstract":"Pinal Creek, Arizona receives an inflow of ground water with high dissolved inorganic carbon (57-75 mg/l) and low pH (5.8-6.3). There is an observed increase of in-stream pH from approximately 6.0-7.8 over the 3 km downstream of the point of groundwater inflow. We hypothesized that CO2 gas-exchange was the most important factor causing the pH increase in this stream-aquifer system. An existing transport model, for coupled ground water-surface water systems (OTIS), was modified to include carbonate equilibria and CO2 degassing, used to simulate alkalinity, total dissolved inorganic carbon (C(T)), and pH in Pinal Creek. Because of the non-linear relation between pH and C(T), the modified transport model used the numerical iteration method to solve the non-linearity. The transport model parameters were determined by the injection of two tracers, bromide and propane. The resulting simulations of alkalinity, C(T) and pH reproduced, without fitting, the overall trends in downstream concentrations. A multi-parametric sensitivity analysis (MPSA) was used to identify the relative sensitivities of the predictions to six of the physical and chemical parameters used in the transport model. MPSA results implied that C(T) and pH in stream water were controlled by the mixing of ground water with stream water and CO2 degassing. The relative importance of these two processes varied spatially depending on the hydrologic conditions, such as stream flow velocity and whether a reach gained or lost stream water caused by the interaction with the ground water. The coupled transport model with CO2 degassing and generalized sensitivity analysis presented in this study can be applied to evaluate carbon transport and pH in other coupled stream-ground water systems.An existing transport model for coupled groundwater-surface water systems was modified to include carbonate equilibria and CO2 degassing. The modified model was used to simulate alkalinity, total dissolved inorganic carbon (CT) and pH in Pinal Creek. The model used the numerical iteration method to solve the nonlinear relation between pH and CT. A multi-parametric sensitivity analysis (MPSA) was used to identify the relative sensitivities of the predictions to six of the physical and chemical parameters used in the transport model. MPSA results implied that CT and pH in the stream water were controlled by the mixing of groundwater with stream water and CO2 degassing.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Hydrology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"Elsevier Sci B.V.","publisherLocation":"Amsterdam, Netherlands","doi":"10.1016/S0022-1694(98)00093-6","issn":"00221694","usgsCitation":"Choi, J., Hulseapple, S., Conklin, M., and Harvey, J., 1998, Modeling CO2 degassing and pH in a stream-aquifer system: Journal of Hydrology, v. 209, no. 1-4, p. 297-310, https://doi.org/10.1016/S0022-1694(98)00093-6.","productDescription":"14 p.","startPage":"297","endPage":"310","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":229719,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":206429,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0022-1694(98)00093-6"}],"volume":"209","issue":"1-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a5bc0e4b0c8380cd6f7a8","contributors":{"authors":[{"text":"Choi, J.","contributorId":42741,"corporation":false,"usgs":true,"family":"Choi","given":"J.","email":"","affiliations":[],"preferred":false,"id":387682,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Hulseapple, S.M.","contributorId":10945,"corporation":false,"usgs":true,"family":"Hulseapple","given":"S.M.","email":"","affiliations":[],"preferred":false,"id":387680,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Conklin, M.H.","contributorId":82875,"corporation":false,"usgs":true,"family":"Conklin","given":"M.H.","email":"","affiliations":[],"preferred":false,"id":387683,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Harvey, J. W. 0000-0002-2654-9873","orcid":"https://orcid.org/0000-0002-2654-9873","contributorId":39725,"corporation":false,"usgs":true,"family":"Harvey","given":"J. W.","affiliations":[],"preferred":false,"id":387681,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ]}