Hydrologic conditions may affect concertrations of organonitrogen herbicides and may be important considerations in complying with drinking water regulations.
The temporal distribution of the herbicides alachlor, atrazine, cyanazine, and metolachlor was documented from September 1991 through August 1992 in the Platte River at Louisville, Neb., the drainage of the Central Nebraska Basins. Lincoln, Omaha, and other municipalities withdraw groundwater for public supplies from the adjacent alluvium, which is hydraulically connected to the Platte River. Data were collected, in part, to provide information to managers, planners, and public utilities on the likelihood of water supplies being adversely affected by these herbicides. Three computational procedures—monthly means, monthly subsampling, and quarterly subsampling—were used to calculate annual mean herbicide concentrations. When the sampling was conducted quarterly rather than monthly, alachlor and atrazine concentrations were more likely to exceed their respective maximum contaminant levels (MCLs) of 2.0 μg/L and 3.0 μg/L, and cyanazine concentrations were more likely to exceed the health advisory level of 1.0 μg/L. The US Environmental Protection Agency has established a tentative MCL of 1.0 μg/L for cyanazine; data indicate that cyanazine is likely to exceed this level under most hydrologic conditions.
","language":"English","publisher":"American Water Works Association","doi":"10.1002/j.1551-8833.1996.tb06504.x","issn":"0003150X","usgsCitation":"Stamer, J., 1996, Water supply implications of herbicide sampling: Journal - American Water Works Association, v. 88, no. 2, p. 76-85, https://doi.org/10.1002/j.1551-8833.1996.tb06504.x.","productDescription":"10 p.","startPage":"76","endPage":"85","numberOfPages":"10","costCenters":[],"links":[{"id":226511,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.er.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"88","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505bcc83e4b08c986b32dbaf","contributors":{"authors":[{"text":"Stamer, J. K.","contributorId":47753,"corporation":false,"usgs":true,"family":"Stamer","given":"J. K.","affiliations":[],"preferred":false,"id":382371,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70019329,"text":"70019329 - 1996 - Reactive solute transport in streams: 2. Simulation of a pH modification experiment","interactions":[],"lastModifiedDate":"2019-02-20T09:43:37","indexId":"70019329","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","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}},"title":"Reactive solute transport in streams: 2. Simulation of a pH modification experiment","docAbstract":"We present an application of an equilibrium-based solute transport model to a pH-modification experiment conducted on the Snake River, an acidic, metal-rich stream located in the Rocky Mountains of Colorado. During the experiment, instream pH decreased from 4.2 to 3.2, causing a marked increase in dissolved iron concentrations. Model application requires specification of several parameters that are estimated using tracer techniques, mass balance calculations, and geochemical data. Two basic questions are addressed through model application: (1) What are the processes responsible for the observed increase in dissolved iron concentrations? (2) Can the identified processes be represented within the equilibrium-based transport model? Simulation results indicate that the increase in iron was due to the dissolution of hydrous iron oxides and the photoreduction of ferric iron. Dissolution from the streambed is represented by considering a trace compartment consisting of freshly precipitated hydrous iron oxide and an abundant compartment consisting of aged precipitates that are less soluble. Spatial variability in the solubility of hydrous iron oxide is attributed to heterogeneity in the streambed sediments, temperature effects, and/or variability in the effects of photoreduction. Solubility products estimated via simulation fall within a narrow range (pKsp from 40.2 to 40.8) relative to the 6 order of magnitude variation reported for laboratory experiments (pKsp from 37.3 to 43.3). Results also support the use of an equilibrium-based transport model as the predominate features of the iron and pH profiles are reproduced. The model provides a valuable tool for quantifying the nature and extent of pH-dependent processes within the context of hydrologic transport.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/95WR03107","usgsCitation":"Runkel, R.L., McKnight, D.M., Bencala, K.E., and Chapra, S.C., 1996, Reactive solute transport in streams: 2. Simulation of a pH modification experiment: Water Resources Research, v. 32, no. 2, p. 419-430, https://doi.org/10.1029/95WR03107.","productDescription":"12 p.","startPage":"419","endPage":"430","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":226510,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"32","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a9588e4b0c8380cd81a93","contributors":{"authors":[{"text":"Runkel, Robert L. 0000-0003-3220-481X runkel@usgs.gov","orcid":"https://orcid.org/0000-0003-3220-481X","contributorId":685,"corporation":false,"usgs":true,"family":"Runkel","given":"Robert","email":"runkel@usgs.gov","middleInitial":"L.","affiliations":[{"id":191,"text":"Colorado Water Science Center","active":true,"usgs":true}],"preferred":true,"id":382369,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"McKnight, Diane M.","contributorId":59773,"corporation":false,"usgs":false,"family":"McKnight","given":"Diane","email":"","middleInitial":"M.","affiliations":[{"id":16833,"text":"INSTAAR, University of Colorado","active":true,"usgs":false}],"preferred":false,"id":382368,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Bencala, Kenneth E. kbencala@usgs.gov","contributorId":1541,"corporation":false,"usgs":true,"family":"Bencala","given":"Kenneth","email":"kbencala@usgs.gov","middleInitial":"E.","affiliations":[],"preferred":true,"id":382370,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Chapra, Steven C.","contributorId":189667,"corporation":false,"usgs":false,"family":"Chapra","given":"Steven","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":382367,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70019315,"text":"70019315 - 1996 - Trends in the chemistry of precipitation and surface water in a national network of small watersheds","interactions":[],"lastModifiedDate":"2024-03-27T11:04:33.084233","indexId":"70019315","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","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":"Trends in the chemistry of precipitation and surface water in a national network of small watersheds","docAbstract":"Trends in precipitation and surface water chemistry at a network of 15 small watersheds ( < 10 km2) in the USA were evaluated using a statistical test for monotonic trends (the seasonal Kendall test) and a graphical smoothing technique for the visual identification of trends. Composite precipitation samples were collected weekly and surface water samples were collected at least monthly. Concentrations were adjusted before trend analysis, by volume for precipitation samples and by flow for surface water samples. A relation between precipitation and surface water trends was not evident either for individual inorganic solutes or for solute combinations, such as ionic strength, at most sites. The only exception was chloride, for which there was a similar trend at 60% of the sites. The smoothing technique indicated that short-term patterns in precipitation chemistry were not reflected in surface waters. The magnitude of the short-term variations in surface water concentration was generally larger than the overall long-term trend, possibly because flow adjustment did not adequately correct for climatic variability. Detecting the relation between precipitation and surface water chemistry trends may be improved by using a more powerful sampling strategy and by developing better methods of concentration adjustment to remove the effects of natural variation in surface waters.","language":"English","publisher":"Wiley","doi":"10.1002/(SICI)1099-1085(199602)10:2<151::AID-HYP355>3.0.CO;2-K","issn":"08856087","usgsCitation":"Aulenbach, B., Hooper, R.P., and Bricker, O., 1996, Trends in the chemistry of precipitation and surface water in a national network of small watersheds: Hydrological Processes, v. 10, no. 2, p. 151-181, https://doi.org/10.1002/(SICI)1099-1085(199602)10:2<151::AID-HYP355>3.0.CO;2-K.","productDescription":"31 p.","startPage":"151","endPage":"181","numberOfPages":"31","costCenters":[],"links":[{"id":226960,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.er.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"10","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505bb810e4b08c986b327662","contributors":{"authors":[{"text":"Aulenbach, Brent T.","contributorId":62766,"corporation":false,"usgs":true,"family":"Aulenbach","given":"Brent T.","affiliations":[],"preferred":false,"id":382327,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Hooper, R. P.","contributorId":26321,"corporation":false,"usgs":true,"family":"Hooper","given":"R.","email":"","middleInitial":"P.","affiliations":[],"preferred":false,"id":382325,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Bricker, O.P.","contributorId":33717,"corporation":false,"usgs":true,"family":"Bricker","given":"O.P.","affiliations":[],"preferred":false,"id":382326,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70019310,"text":"70019310 - 1996 - Observed and simulated movement of bank-storage water","interactions":[],"lastModifiedDate":"2020-01-07T13:44:39","indexId":"70019310","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","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":"Observed and simulated movement of bank-storage water","docAbstract":"Detailed hydrologic and water-chemistry data were collected that document the movement of bank-storage water during March 7-April 17, 1990, in an alluvial aquifer adjacent to the Cedar River, Iowa. Hydrologic data included 745 daily ground-water-level measurements from 27 observation wells. Water-chemistry data indicate that bank-storage water had smaller specific conductance and larger concentration of atrazine than ambient ground water. To quantify the movement of the bank-storage water, a two-dimensional ground-water flow model was constructed, and the resulting calibrated model accurately simulated observed conditions. Analysis of water chemistry and model results indicate that a 2-meter rise in the river stage caused bank-storage water to move horizontally at least 30 meters into the aquifer and vertically about 4 meters below the river bottom, whereas the remaining 30 percent moved laterally through the riverbank. The model also showed that bank storage caused the ground-water flux to the river to increase by a factor of five during the first three weeks of base flow after runoff and that it required about five weeks for bank-storage water to discharge from the alluvial aquifer after the peak river stage. These results quantitatively demonstrate the importance of bank storage as a source of recharge to the alluvial aquifer and as a source of water to the river during early base-flow conditions.
","language":"English","publisher":"Wiley","doi":"10.1111/j.1745-6584.1996.tb01872.x","issn":"0017467X","usgsCitation":"Squillace, P.J., 1996, Observed and simulated movement of bank-storage water: Ground Water, v. 34, no. 1, p. 121-134, https://doi.org/10.1111/j.1745-6584.1996.tb01872.x.","productDescription":"14 p.","startPage":"121","endPage":"134","numberOfPages":"14","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":351,"text":"Iowa Water Science Center","active":true,"usgs":true},{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":226874,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Iowa","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -91.53173446655273,\n 41.91415807933598\n ],\n [\n -91.53173446655273,\n 41.930219515373096\n ],\n [\n -91.50856018066406,\n 41.930219515373096\n ],\n [\n -91.50856018066406,\n 41.91415807933598\n ],\n [\n -91.53173446655273,\n 41.91415807933598\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"34","issue":"1","noUsgsAuthors":false,"publicationDate":"2005-08-04","publicationStatus":"PW","scienceBaseUri":"505a6aebe4b0c8380cd74406","contributors":{"authors":[{"text":"Squillace, P. J.","contributorId":8878,"corporation":false,"usgs":true,"family":"Squillace","given":"P.","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":382310,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70019304,"text":"70019304 - 1996 - The relationships among three habitat scales and stream benthic invertebrate community structure","interactions":[],"lastModifiedDate":"2019-02-20T08:34:34","indexId":"70019304","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1696,"text":"Freshwater Biology","active":true,"publicationSubtype":{"id":10}},"title":"The relationships among three habitat scales and stream benthic invertebrate community structure","docAbstract":"1. The relationships between three habitat scales and lotic invertebrate species composition were investigated for the 15 540 km2 Yakima River basin in south-central Washington, U.S.A.
\n2. The three spatial scales were sample (the sampled riffle), reach (a length of ten–twenty stream widths) and segment (a length of stream of nearly uniform slope and valley form having no change in stream order).
\n3. Physical variables were highly correlated between scales and expressed a relationship between altitude, basin form and small-scale physical structure.
\n4. Multiple discriminant function analyses indicated that segment- and reach-scale variables discriminated among species-defined groups better than sample-scale variables.
\n5. Species composition varied along a complex altitudinal gradient of changing basin form and resultant land use.
\n6. There was no clear relationship between species richness and altitude on a site basis. However, when viewed at the basin scale, maximum richness was observed at the transition between montane and valley sites.
","language":"English","publisher":"Wiley","doi":"10.1046/j.1365-2427.1996.d01-450.x","issn":"00465070","usgsCitation":"Carter, J., Fend, S., and Kennelly, S., 1996, The relationships among three habitat scales and stream benthic invertebrate community structure: Freshwater Biology, v. 35, no. 1, p. 109-124, https://doi.org/10.1046/j.1365-2427.1996.d01-450.x.","productDescription":"16 p.","startPage":"109","endPage":"124","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true},{"id":622,"text":"Washington Water Science Center","active":true,"usgs":true}],"links":[{"id":226781,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"35","issue":"1","noUsgsAuthors":false,"publicationDate":"2003-10-30","publicationStatus":"PW","scienceBaseUri":"505baf27e4b08c986b3245b7","contributors":{"authors":[{"text":"Carter, J.L.","contributorId":26030,"corporation":false,"usgs":true,"family":"Carter","given":"J.L.","email":"","affiliations":[],"preferred":false,"id":382298,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"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":382300,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Kennelly, S.S.","contributorId":75697,"corporation":false,"usgs":true,"family":"Kennelly","given":"S.S.","email":"","affiliations":[],"preferred":false,"id":382299,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70019299,"text":"70019299 - 1996 - The accuracy of seismic estimates of dynamic strains: an evaluation using strainmeter and seismometer data from Piñon Flat Observatory, California","interactions":[],"lastModifiedDate":"2023-10-22T14:16:21.258696","indexId":"70019299","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1135,"text":"Bulletin of the Seismological Society of America","onlineIssn":"1943-3573","printIssn":"0037-1106","active":true,"publicationSubtype":{"id":10}},"title":"The accuracy of seismic estimates of dynamic strains: an evaluation using strainmeter and seismometer data from Piñon Flat Observatory, California","docAbstract":"The dynamic strains associated with seismic waves may play a significant role in earthquake triggering, hydrological and magmatic changes, earthquake damage, and ground failure. We determine how accurately dynamic strains may be estimated from seismometer data and elastic-wave theory by comparing such estimated strains with strains measured on a three-component long-base strainmeter system at Piñon Flat, California. We quantify the uncertainties and errors through cross-spectral analysis of data from three regional earthquakes (the M0 = 4 × 1017 N-m St. George, Utah; M0 = 4 × 1017 N-m Little Skull Mountain, Nevada; and M0 = 1 × 1019 N-m Northridge, California, events at distances of 470, 345, and 206 km, respectively). Our analysis indicates that in most cases the phase of the estimated strain matches that of the observed strain quite well (to within the uncertainties, which are about ±0.1 to ±0.2 cycles). However, the amplitudes are often systematically off, at levels exceeding the uncertainties (about 20%); in one case, the predicted strain amplitudes are nearly twice those observed. We also observe significant ɛφφ strains (φ = tangential direction), which should be zero theoretically; in the worst case, the rms ɛφφ strain exceeds the other nonzero components. These nonzero ɛφφ strains cannot be caused by deviations of the surface-wave propagation paths from the expected azimuth or by departures from the plane-wave approximation. We believe that distortion of the strain field by topography or material heterogeneities give rise to these complexities.
Loss of fluids and samples during retrieval of cores of saturated, noncohesive sediments results in incorrect measures of fluid distributions and an inaccurate measure of the stratigraphic position of the sample. To reduce these errors, we developed a hollow drive shoe that freezes in place the lowest 3 inches (75 mm) of a 1.88‐inch‐diameter (48 mm), 5‐foot‐long (1.5 m) sediment sample taken using a commercial wire line piston core smapler. The end of the core is frozen by piping liquid carbon dioxide at ambient temperature through a steel tube from a bottle at the land surface to the drive shoe where it evaporates and expands, cooling the interior surface of the shoe to about ‐ 109°F (‐ 78°C). Freezing a core end takes about 10 minutes. The device was used to collect samples for a study of oil‐water‐air distributions, and for studies of water chemistry and microbial activity in unconsolidated sediments at the site of an oil spill near Bemidji, Minnesota. Before freezing was employed, samples of sandy sediments from near the water table sometimes flowed out of the core barrel as the sampler was withdrawn. Freezing the bottom of the core allowed for the retention of all material that entered the core barrel and lessened the redistribution of fluids within the core. The device is useful in the unsaturated and shallow saturated zones, but does not freeze cores well at depths greater than about 20 feet (6 m) below water, possibly because the feed tube plugs with dry ice with increased exhaust back‐pressure, or because sediment enters the annulus between the core barrel and the core barrel liner and blocks the exhaust.
Stream water was locally recharged into shallow groundwater flow paths that returned to the stream (hyporheic exchange) in St. Kevin Gulch, a Rocky Mountain stream in Colorado contaminated by acid mine drainage. Two approaches were used to characterize hyporheic exchange: sub-reach-scale measurement of hydraulic heads and hydraulic conductivity to compute streambed fluxes (hydrometric approach) and reachscale modeling of in-stream solute tracer injections to determine characteristic length and timescales of exchange with storage zones (stream tracer approach). Subsurface data were the standard of comparison used to evaluate the reliability of the stream tracer approach to characterize hyporheic exchange. The reach-averaged hyporheic exchange flux (1.5 mL s−1 m−1), determined by hydrometric methods, was largest when stream base flow was low (10 L s−1); hyporheic exchange persisted when base flow was 10-fold higher, decreasing by approximately 30%. Reliability of the stream tracer approach to detect hyporheic exchange was assessed using first-order uncertainty analysis that considered model parameter sensitivity. The stream tracer approach did not reliably characterize hyporheic exchange at high base flow: the model was apparently more sensitive to exchange with surface water storage zones than with the hyporheic zone. At low base flow the stream tracer approach reliably characterized exchange between the stream and gravel streambed (timescale of hours) but was relatively insensitive to slower exchange with deeper alluvium (timescale of tens of hours) that was detected by subsurface measurements. The stream tracer approach was therefore not equally sensitive to all timescales of hyporheic exchange. We conclude that while the stream tracer approach is an efficient means to characterize surface-subsurface exchange, future studies will need to more routinely consider decreasing sensitivities of tracer methods at higher base flow and a potential bias toward characterizing only a fast component of hyporheic exchange. Stream tracer models with multiple rate constants to consider both fast exchange with streambed gravel and slower exchange with deeper alluvium appear to be warranted.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/96WR01268","usgsCitation":"Harvey, J.W., Wagner, B.J., and Bencala, K.E., 1996, Evaluating the reliability of the stream tracer approach to characterize stream-subsurface water exchange: Water Resources Research, v. 32, no. 8, p. 2441-2451, https://doi.org/10.1029/96WR01268.","productDescription":"11 p.","startPage":"2441","endPage":"2451","costCenters":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true},{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":226356,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"32","issue":"8","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a0bfee4b0c8380cd529b3","contributors":{"authors":[{"text":"Harvey, Judson W. 0000-0002-2654-9873 jwharvey@usgs.gov","orcid":"https://orcid.org/0000-0002-2654-9873","contributorId":1796,"corporation":false,"usgs":true,"family":"Harvey","given":"Judson","email":"jwharvey@usgs.gov","middleInitial":"W.","affiliations":[{"id":436,"text":"National Research Program - Eastern Branch","active":true,"usgs":true}],"preferred":true,"id":381375,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Wagner, Brian J. bjwagner@usgs.gov","contributorId":427,"corporation":false,"usgs":true,"family":"Wagner","given":"Brian","email":"bjwagner@usgs.gov","middleInitial":"J.","affiliations":[],"preferred":true,"id":381374,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Bencala, Kenneth E. kbencala@usgs.gov","contributorId":1541,"corporation":false,"usgs":true,"family":"Bencala","given":"Kenneth","email":"kbencala@usgs.gov","middleInitial":"E.","affiliations":[],"preferred":true,"id":381376,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70018978,"text":"70018978 - 1996 - Inferring shallow groundwater flow in saprolite and fractured rock using environmental tracers","interactions":[],"lastModifiedDate":"2020-01-07T13:01:37","indexId":"70018978","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","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}},"title":"Inferring shallow groundwater flow in saprolite and fractured rock using environmental tracers","docAbstract":"The Ridge and Valley Province of eastern Tennessee is characterized by (1) substantial topographic relief, (2) folded and highly fractured rocks of various lithologies that have low primary permeability and porosity, and (3) a shallow residuum of medium permeability and high total porosity. Conceptual models of shallow groundwater flow and solute transport in this system have been developed but are difficult to evaluate using physical characterization or short‐term tracer methods due to extreme spatial variability in hydraulic properties. In this paper we describe how chlorofluorocarbon 12, 3H, and 3He were used to infer groundwater flow and solute transport in saprolite and fractured rock near Oak Ridge, Tennessee. In the shallow residuum, fracture spacings are <0.05 m, suggesting that concentrations of these tracers in fractures and in the matrix have time to diffusionally equilibrate. The relatively smooth nature of tracer concentrations with depth in the residuum is consistent with this model and quantitatively suggests recharge fluxes of 0.2 to 0.4 m yr−1. In contrast, groundwater flow within the unweathered rock appears to be controlled by fractures with spacings of the order of 2 to 5 m, and diffusional equilibration of fractures and matrix has not occurred. For this reason, vertical fluid fluxes in the unweathered rock cannot be estimated from the tracer data.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/96WR00354","usgsCitation":"Cook, P., Solomon, D.K., Sanford, W., Busenberg, E., Plummer, N., and Poreda, R., 1996, Inferring shallow groundwater flow in saprolite and fractured rock using environmental tracers: Water Resources Research, v. 32, no. 6, p. 1501-1509, https://doi.org/10.1029/96WR00354.","productDescription":"9 p.","startPage":"1501","endPage":"1509","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":226531,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"32","issue":"6","noUsgsAuthors":false,"publicationDate":"2010-07-09","publicationStatus":"PW","scienceBaseUri":"505a3aebe4b0c8380cd620a4","contributors":{"authors":[{"text":"Cook, P.G.","contributorId":103807,"corporation":false,"usgs":true,"family":"Cook","given":"P.G.","email":"","affiliations":[],"preferred":false,"id":381266,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Solomon, D. K.","contributorId":98324,"corporation":false,"usgs":false,"family":"Solomon","given":"D.","email":"","middleInitial":"K.","affiliations":[],"preferred":false,"id":381264,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Sanford, W. E. 0000-0002-6624-0280","orcid":"https://orcid.org/0000-0002-6624-0280","contributorId":102112,"corporation":false,"usgs":true,"family":"Sanford","given":"W. E.","affiliations":[],"preferred":false,"id":381265,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Busenberg, E.","contributorId":56796,"corporation":false,"usgs":true,"family":"Busenberg","given":"E.","affiliations":[],"preferred":false,"id":381261,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"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":381262,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Poreda, R.J.","contributorId":97138,"corporation":false,"usgs":true,"family":"Poreda","given":"R.J.","email":"","affiliations":[],"preferred":false,"id":381263,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}} ,{"id":70018967,"text":"70018967 - 1996 - Integrated borehole logging methods for wellhead protection applications","interactions":[],"lastModifiedDate":"2019-03-04T20:08:56","indexId":"70018967","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1517,"text":"Engineering Geology","active":true,"publicationSubtype":{"id":10}},"title":"Integrated borehole logging methods for wellhead protection applications","docAbstract":"Modeling of ground water infiltration and movement in the wellhead area is a critical part of an effective wellhead protection program. Such models depend on an accurate description of the aquifer in the wellhead area so that reliable estimates of contaminant travel times can be used in defining a protection area. Geophysical and hydraulic measurements in boreholes provide one of the most important methods for obtaining the data needed to specify wellhead protection measures. Most effective characterization of aquifers in the wellhead vicinity results when a variety of geophysical and hydraulic measurements are made where geophysical measurements can be calibrated in terms of hydraulic variables, and where measurements are made at somewhat different scales of investigation. The application of multiple geophysical measurements to ground water flow in the wellhead area is illustrated by examples in alluvial, fractured sedimentary, and fractured crystalline rock aquifers. Data obtained from a single test well are useful, but cannot indicate how conductive elements in the aquifer are connected to form large-scale flow paths. Geophysical and hydraulic measurements made in arrays of observation boreholes can provide information about such large-scale flow paths, and are especially useful in specifying aquifer properties in wellhead protection studies.","language":"English","publisher":"Elsevier","doi":"10.1016/0013-7952(95)00077-1","issn":"00137952","usgsCitation":"Paillet, F.L., and Pedler, W., 1996, Integrated borehole logging methods for wellhead protection applications: Engineering Geology, v. 42, no. 2-3, p. 155-165, https://doi.org/10.1016/0013-7952(95)00077-1.","productDescription":"11 p.","startPage":"155","endPage":"165","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":226396,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"42","issue":"2-3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a3c5de4b0c8380cd62ca7","contributors":{"authors":[{"text":"Paillet, Frederick L.","contributorId":63820,"corporation":false,"usgs":true,"family":"Paillet","given":"Frederick","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":381233,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Pedler, W.H.","contributorId":26456,"corporation":false,"usgs":true,"family":"Pedler","given":"W.H.","affiliations":[],"preferred":false,"id":381232,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70018913,"text":"70018913 - 1996 - Properties and variability of soil and trench fill at an arid waste-burial site","interactions":[],"lastModifiedDate":"2019-02-14T07:42:56","indexId":"70018913","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3420,"text":"Soil Science Society of America Journal","active":true,"publicationSubtype":{"id":10}},"title":"Properties and variability of soil and trench fill at an arid waste-burial site","docAbstract":"Arid sites commonly are assumed to be ideal for long-term isolation of wastes. Information on properties and variability of desert soils is limited, however, and little is known about how the natural site environment is altered by installation of a waste facility. During fall construction of two test trenches next to the waste facility on the Amargosa Desert near Beatty, NV, samples were collected to: (i) characterize physical and hydraulic properties of native soil (upper 5 m) and trench fill, (ii) determine effects of trench construction on selected properties and vertical variability of these properties, and (iii) develop conceptual models of vertical variation within the soil profile and trench fill. Water retention was measured to air dryness (ψ = 2 × 106 cm water suction). The 15 300-cm pressure-plate data were omitted from the analysis because water-activity measurements showed the actual suction values were significantly less than the expected 15 300-cm value (avg. difference = 8550 ± 2460 cm water). Trench construction significantly altered properties and variability of the natural site environment. For example, water content ranged from 0.029 to 0.041 m3 m-3 for fill vs. 0.030 to 0.095 m3 m-3 for soil; saturated hydraulic conductivity was ≈ 10-4 cm s-1 for fill vs. 10-2 to ≈ 10-4 cm s-1 for soil. Statistical analyses showed that the native soil may be represented by three major horizontal components and the fill by a single component. Under initial conditions, calculated liquid conductivity (Kl) plus isothermal vapor conductivity (Kv) for the upper two soil layers and the trench fill was ≈ 10-13 cm s-1, and Kl was ≤ Kv. For the deeper (2–5 m) soil, total conductivity was ≈ 10-10 cm s-1, and Kl was >Kv. This study quantitatively describes hydraulic characteristics of a site using data measured across a water-content range that is representative of arid conditions, but is seldom studied.
","language":"English","publisher":"ACSESS","doi":"10.2136/sssaj1996.03615995006000010011x","usgsCitation":"Andraski, B.J., 1996, Properties and variability of soil and trench fill at an arid waste-burial site: Soil Science Society of America Journal, v. 60, no. 1, p. 54-66, https://doi.org/10.2136/sssaj1996.03615995006000010011x.","productDescription":"13 p.","startPage":"54","endPage":"66","costCenters":[{"id":465,"text":"Nevada Water Science Center","active":true,"usgs":true},{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":226264,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"60","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a8f21e4b0c8380cd7f5c9","contributors":{"authors":[{"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":465,"text":"Nevada Water Science Center","active":true,"usgs":true},{"id":438,"text":"National Research Program - Western Branch","active":true,"usgs":true},{"id":38175,"text":"Toxics Substances Hydrology Program","active":true,"usgs":true}],"preferred":false,"id":381087,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70018889,"text":"70018889 - 1996 - Reactive solute transport in an acidic stream: Experimental pH increase and simulation of controls on pH, aluminum, and iron","interactions":[],"lastModifiedDate":"2019-02-20T09:13:36","indexId":"70018889","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","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":"Reactive solute transport in an acidic stream: Experimental pH increase and simulation of controls on pH, aluminum, and iron","docAbstract":"Solute transport simulations quantitatively constrained hydrologic and geochemical hypotheses about field observations of a pH modification in an acid mine drainage stream. Carbonate chemistry, the formation of solid phases, and buffering interactions with the stream bed were important factors in explaining the behavior of pH, aluminum, and iron. The precipitation of microcrystalline gibbsite accounted for the behavior of aluminum; precipitation of Fe(OH)3 explained the general pattern of iron solubility. The dynamic experiment revealed limitations on assumptions that reactions were controlled only by equilibrium chemistry. Temporal variation in relative rates of photoreduction and oxidation influenced iron behavior. Kinetic limitations on ferrous iron oxidation and hydrous oxide precipitation and the effects of these limitations on field filtration were evident. Kinetic restraints also characterized interaction between the water column and the stream bed, including sorption and desorption of protons from iron oxides at the sediment-water interface and post-injection dissolution of the precipitated aluminum solid phase.","language":"English","publisher":"ACS","doi":"10.1021/es960055u","issn":"0013936X","usgsCitation":"Broshears, R.E., Runkel, R., Kimball, B.A., McKnight, D.M., and Bencala, K., 1996, Reactive solute transport in an acidic stream: Experimental pH increase and simulation of controls on pH, aluminum, and iron: Environmental Science & Technology, v. 30, no. 10, p. 3016-3024, https://doi.org/10.1021/es960055u.","productDescription":"9 p.","startPage":"3016","endPage":"3024","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":205776,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1021/es960055u"},{"id":226711,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"30","issue":"10","noUsgsAuthors":false,"publicationDate":"1996-09-26","publicationStatus":"PW","scienceBaseUri":"505a9586e4b0c8380cd81a87","contributors":{"authors":[{"text":"Broshears, R. E.","contributorId":75552,"corporation":false,"usgs":true,"family":"Broshears","given":"R.","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":381028,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Runkel, R.L.","contributorId":97529,"corporation":false,"usgs":true,"family":"Runkel","given":"R.L.","affiliations":[],"preferred":false,"id":381030,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Kimball, B. A.","contributorId":87583,"corporation":false,"usgs":false,"family":"Kimball","given":"B.","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":381029,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"McKnight, Diane M.","contributorId":59773,"corporation":false,"usgs":false,"family":"McKnight","given":"Diane","email":"","middleInitial":"M.","affiliations":[{"id":16833,"text":"INSTAAR, University of Colorado","active":true,"usgs":false}],"preferred":false,"id":381027,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Bencala, K.E.","contributorId":105312,"corporation":false,"usgs":true,"family":"Bencala","given":"K.E.","email":"","affiliations":[],"preferred":false,"id":381031,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":1001139,"text":"1001139 - 1996 - A test of vegetation-related indicators of wetland quality in the prairie pothole region","interactions":[],"lastModifiedDate":"2017-12-29T12:48:42","indexId":"1001139","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2178,"text":"Journal of Aquatic Ecosystem Health","active":true,"publicationSubtype":{"id":10}},"title":"A test of vegetation-related indicators of wetland quality in the prairie pothole region","docAbstract":"This study was part of an effort by the U.S. Environmental Protection Agency to quantitatively assess the environmental quality or 'health' of wetland resources on regional and national scales. During a two-year pilot study, we tested selected indicators of wetland quality in the U.S. portion of the prairie pothole region (PPR). We assumed that the amount of cropland versus non-cropland (mostly grassland) in the plots containing these basins was a proxy for their quality. We then tested indicators by their ability to discriminate between wetlands at the extremes of that proxy. Amounts of standing dead vegetation were greater in zones of greater water permanence. Depth of litter was greater in zones of greater water permanence and in zones of basins in poor-quality watersheds. Amounts of unvegetated bottom were greater in basins in poor-quality watersheds; lesser amounts occurred in all wetlands during a wetter year. Greater amounts of open water occurred during a wetter year and in zones of greater water permanence. When unadjusted for areas (ha) of communities, plant taxon richness was higher in wet-meadow and shallow-marsh zones in good-quality watersheds than in similar zones in poor-quality watersheds. Wet-meadow zones in good-quality watersheds had greater numbers of native perennials than those in poor-quality watersheds. This relation held when we eliminated all communities in good-quality watersheds larger than the largest communities in poor-quality watersheds from the data set. We conclude that although amounts of unvegetated bottom and plant taxon richness in wet-meadow zones were useful indicators of wetland quality during our study, the search for additional such indicators should continue. The value of these indicators may change with the notoriously unstable hydrological conditions in the PPR. Most valuable would be indicators that could be photographed or otherwise remotely sensed and would remain relatively stable under various hydrological conditions. An ideal set of indicators could detect the absence of stressors, as well as the presence of structures or functions, of known value to major groups of organisms.
","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Aquatic Ecosystem Health","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1007/BF00124105","usgsCitation":"Kantrud, H., and Newton, W., 1996, A test of vegetation-related indicators of wetland quality in the prairie pothole region: Journal of Aquatic Ecosystem Health, v. 5, p. 177-191, https://doi.org/10.1007/BF00124105.","productDescription":"15 p.","startPage":"177","endPage":"191","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":480,"text":"Northern Prairie Wildlife Research Center","active":true,"usgs":true}],"links":[{"id":133835,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"5","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4b05e4b07f02db699cbb","contributors":{"authors":[{"text":"Kantrud, H.A.","contributorId":28553,"corporation":false,"usgs":true,"family":"Kantrud","given":"H.A.","email":"","affiliations":[],"preferred":false,"id":310572,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Newton, W.E.","contributorId":13567,"corporation":false,"usgs":true,"family":"Newton","given":"W.E.","email":"","affiliations":[],"preferred":false,"id":310571,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70018834,"text":"70018834 - 1996 - Occurrence of selected pesticides and their metabolites in near-surface aquifers of the midwestern United States","interactions":[],"lastModifiedDate":"2019-02-19T06:27:59","indexId":"70018834","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","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":"Occurrence of selected pesticides and their metabolites in near-surface aquifers of the midwestern United States","docAbstract":"The occurrence and distribution of selected pesticides and their metabolites were investigated through the collection of 837 water-quality samples from 303 wells across the Midwest. Results of this study showed that five of the six most frequently detected compounds were pesticide metabolites. Thus, it was common for a metabolite to be found more frequently in groundwater than its parent compound. The metabolite alachlor ethanesulfonic acid (alachlor-ESA; 2-[(2,6-diethylphenyl)(methoxymethyl)amino]-2-oxoethanesulfonic acid) was detected almost 10 times as frequently and at much higher concentrations than its parent compound alachlor (2-chloro-2‘,6‘-diethyl-N-(methoxymethyl)acetamide). The median detectable atrazine (2-chloro-4-ethylamino-6- isopropylamino-s-triazine) concentration was almost half that of atrazine residue (atrazine plus the two atrazine metabolites analyzed). Cyanazine amide [2-chloro-4-(1-carbamoyl-1-methylethylamino)-6-ethylamino-s-triazine] was detected almost twice as frequently as cyanazine (2-chloro-4-ethylamino-6-methylpropionitrileamino-s-triazine). Results show that information on pesticide metabolites is necessary to understand the environmental fate of pesticides. Consequently, if pesticide metabolites are not quantified, the effects of chemical use on groundwater quality would be substantially underestimated. Thus, continued research is needed to identify major degradation pathways for all pesticides and to develop analytical methods to determine their concentrations in water and other environmental media.
","language":"English","publisher":"American Chemical Society","doi":"10.1021/es950462q","issn":"0013936X","usgsCitation":"Kolpin, D., Michael, T.E., and Goolsby, D.A., 1996, Occurrence of selected pesticides and their metabolites in near-surface aquifers of the midwestern United States: Environmental Science & Technology, v. 30, no. 1, p. 335-340, https://doi.org/10.1021/es950462q.","productDescription":"6 p.","startPage":"335","endPage":"340","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":351,"text":"Iowa Water Science Center","active":true,"usgs":true},{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":226662,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":205767,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1021/es950462q"}],"country":"United States","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -81.298828125, 41.705728515237524 ], [ -80.52978515625, 41.36031866306708 ], [ -80.52978515625, 40.613952441166596 ], [ -81.49658203125, 40.195659093364654 ], [ -81.8701171875, 39.825413103424786 ], [ -82.9248046875, 39.35129035526705 ], [ -83.78173828125, 39.30029918615029 ], [ -84.83642578125, 39.14710270770074 ], [ -85.53955078125, 38.788345355085625 ], [ -85.97900390625, 38.496593518947556 ], [ -86.37451171875, 38.11727165830543 ], [ -86.66015624999999, 37.89219554724437 ], [ -86.923828125, 38.013476231041935 ], [ -87.0556640625, 37.78808138412046 ], [ -87.42919921875, 37.89219554724437 ], [ -87.890625, 37.80544394934274 ], [ -88.11035156249999, 37.579412513438385 ], [ -88.08837890625, 37.474858084971046 ], [ -88.43994140625, 37.33522435930641 ], [ -88.3740234375, 37.055177106660814 ], [ -88.72558593749999, 37.03763967977139 ], [ -88.9892578125, 37.142803443716836 ], [ -88.96728515624999, 36.932330061503144 ], [ -89.6044921875, 37.19533058280065 ], [ -89.47265625, 37.37015718405753 ], [ -89.53857421875, 37.61423141542417 ], [ -89.97802734375, 37.94419750075404 ], [ -90.41748046874999, 38.20365531807149 ], [ -91.12060546875, 38.013476231041935 ], [ -92.1533203125, 37.90953361677018 ], [ -93.01025390625, 37.96152331396616 ], [ -93.80126953124999, 37.96152331396616 ], [ -94.5703125, 38.20365531807149 ], [ -94.68017578125, 38.70265930723801 ], [ -94.921875, 39.06184913429154 ], [ -95.2734375, 39.707186656826565 ], [ -95.44921875, 39.8928799002948 ], [ -101.2060546875, 39.926588421909436 ], [ -101.42578124999999, 40.3130432088809 ], [ -101.66748046874999, 40.64730356252251 ], [ -102.0849609375, 40.979898069620155 ], [ -102.041015625, 41.27780646738183 ], [ -100.96435546875, 42.114523952464246 ], [ -100.107421875, 42.66628070564928 ], [ -99.55810546875, 42.97250158602597 ], [ -98.81103515625, 43.42100882994726 ], [ -97.119140625, 43.75522505306928 ], [ -96.591796875, 43.8186748554532 ], [ -96.65771484375, 44.512176171071054 ], [ -96.61376953125, 45.22848059584359 ], [ -96.96533203125, 45.61403741135093 ], [ -98.26171875, 45.85941212790755 ], [ -98.37158203125, 46.10370875598026 ], [ -97.71240234375, 46.13417004624326 ], [ -95.5810546875, 46.604167162931844 ], [ -95.29541015625, 46.33175800051563 ], [ -92.724609375, 45.62940492064501 ], [ -91.7578125, 45.42929873257377 ], [ -90.94482421875, 45.042478050891546 ], [ -89.9560546875, 44.762336674810996 ], [ -89.14306640625, 44.731125592643274 ], [ -88.4619140625, 44.55916341529184 ], [ -88.0224609375, 44.33956524809713 ], [ -87.5830078125, 44.15068115978091 ], [ -87.91259765625, 43.89789239125797 ], [ -88.13232421875, 43.628123412124616 ], [ -88.1982421875, 43.14909399920127 ], [ -88.1982421875, 42.293564192170095 ], [ -88.00048828124999, 41.78769700539063 ], [ -87.60498046875, 41.393294288784865 ], [ -86.72607421875, 41.50857729743935 ], [ -86.0009765625, 41.902277040963696 ], [ -85.93505859374999, 42.48830197960227 ], [ -86.1328125, 42.85985981506279 ], [ -86.484375, 43.35713822211053 ], [ -86.2646484375, 43.51668853502909 ], [ -85.62744140625, 43.51668853502909 ], [ -85.25390625, 43.43696596521823 ], [ -84.39697265625, 43.37311218382002 ], [ -83.56201171875, 43.35713822211053 ], [ -83.03466796874999, 43.35713822211053 ], [ -82.96875, 43.02071359427862 ], [ -83.1884765625, 42.81152174509788 ], [ -83.3642578125, 42.391008609205045 ], [ -83.69384765625, 41.918628865183045 ], [ -83.56201171875, 41.64007838467894 ], [ -83.25439453125, 41.64007838467894 ], [ -82.7490234375, 41.393294288784865 ], [ -82.30957031249999, 41.393294288784865 ], [ -81.84814453125, 41.492120839687786 ], [ -81.298828125, 41.705728515237524 ] ] ] } } ] }","volume":"30","issue":"1","noUsgsAuthors":false,"publicationDate":"1995-12-27","publicationStatus":"PW","scienceBaseUri":"505a6c30e4b0c8380cd74acb","contributors":{"authors":[{"text":"Kolpin, D.W.","contributorId":87565,"corporation":false,"usgs":true,"family":"Kolpin","given":"D.W.","email":"","affiliations":[],"preferred":false,"id":380889,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Michael, Thurman E.","contributorId":86116,"corporation":false,"usgs":true,"family":"Michael","given":"Thurman","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":380888,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Goolsby, D. A.","contributorId":50508,"corporation":false,"usgs":true,"family":"Goolsby","given":"D.","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":380887,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70018808,"text":"70018808 - 1996 - Acetochlor in the hydrologic system in the midwestern United States, 1994","interactions":[],"lastModifiedDate":"2019-02-19T06:23:01","indexId":"70018808","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","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":"Acetochlor in the hydrologic system in the midwestern United States, 1994","docAbstract":"The herbicide acetochlor [2-chloro-N-(ethoxymethyl)-N-(2-ethyl-6-methylphenyl)acetamide] was given conditional registration in the United States by the U.S. Environmental Protection Agency in March 1994. This registration provided a rare opportunity to investigate the occurrence of a pesticide during its first season of extensive use in the midwestern United States. Water samples collected and analyzed by the U.S. Geological Survey during 1994 documented the distribution of acetochlor in the hydrologic system; it was detected in 29% of the rain samples from four sites in Iowa, 17% of the stream samples from 51 sites across nine states, and 0% of the groundwater samples from 38 wells across eight states. Acetochlor exhibited concentration increases in rain and streams following its application to corn in the midwestern United States, with 75% of the rainwater and 35% of the stream samples having acetochlor detected during this time period. Acetochlor concentrations in rain decreased as the growing season progressed. Based on the limited data collected for this study, it is anticipated that acetochlor concentrations will have a seasonal pattern in rain and streams similar to those of other acetanilide herbicides examined. Possible explanations for the absence of acetochlor in groundwater for this study include the rapid degradation of acetochlor in the soil zone, insufficient time for this first extensive use of acetochlor to have reached the aquifers sampled, and the possible lack of acetochlor use in the recharge areas for the wells examined.
","language":"English","publisher":"American Chemical Society","doi":"10.1021/es9503241","issn":"0013936X","usgsCitation":"Kolpin, D., Nations, B., Goolsby, D.A., and Thurman, E., 1996, Acetochlor in the hydrologic system in the midwestern United States, 1994: Environmental Science & Technology, v. 30, no. 5, p. 1459-1464, https://doi.org/10.1021/es9503241.","productDescription":"6 p.","startPage":"1459","endPage":"1464","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":351,"text":"Iowa Water Science Center","active":true,"usgs":true},{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":227052,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":205840,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1021/es9503241"}],"country":"United States","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -80.5517578125,\n 41.934976500546604\n ],\n [\n -80.4638671875,\n 40.58058466412764\n ],\n [\n -80.68359375,\n 40.56389453066509\n ],\n [\n -80.8154296875,\n 39.9434364619742\n ],\n [\n -80.947265625,\n 39.65645604812829\n ],\n [\n -81.32080078125,\n 39.35129035526705\n ],\n [\n -81.5625,\n 39.402244340292775\n ],\n [\n -81.73828125,\n 39.13006024213511\n ],\n [\n -81.650390625,\n 38.839707613545144\n ],\n [\n -81.8701171875,\n 38.839707613545144\n ],\n [\n -82.06787109374999,\n 38.87392853923629\n ],\n [\n -83.91357421875,\n 38.77121637244273\n ],\n [\n -84.26513671875,\n 38.805470223177466\n ],\n [\n -84.30908203125,\n 38.94232097947902\n ],\n [\n -84.4189453125,\n 39.027718840211605\n ],\n [\n -84.814453125,\n 39.095962936305504\n ],\n [\n -84.74853515625,\n 38.87392853923629\n ],\n [\n -85.341796875,\n 38.736946065676\n ],\n [\n -85.49560546875,\n 38.5825261593533\n ],\n [\n -85.6494140625,\n 38.30718056188316\n ],\n [\n -85.869140625,\n 38.22091976683121\n ],\n [\n -85.9130859375,\n 37.97884504049713\n ],\n [\n -86.220703125,\n 38.013476231041935\n ],\n [\n -86.33056640625,\n 38.18638677411551\n ],\n [\n -86.572265625,\n 37.85750715625203\n ],\n [\n -86.77001953125,\n 37.89219554724437\n ],\n [\n -87.0556640625,\n 37.78808138412046\n ],\n [\n -87.34130859375,\n 37.87485339352928\n ],\n [\n -87.64892578125,\n 37.77071473849609\n ],\n [\n -88.0224609375,\n 37.82280243352756\n ],\n [\n -88.17626953125,\n 37.61423141542417\n ],\n [\n -87.978515625,\n 37.45741810262938\n ],\n [\n -88.39599609375,\n 37.35269280367274\n ],\n [\n -89.20898437499999,\n 37.16031654673677\n ],\n [\n -89.12109375,\n 36.8092847020594\n ],\n [\n -89.4287109375,\n 36.50963615733049\n ],\n [\n -89.69238281249999,\n 35.96022296929667\n ],\n [\n -90.46142578125,\n 35.99578538642032\n ],\n [\n -90.1318359375,\n 36.35052700542763\n ],\n [\n -90.1318359375,\n 36.491973470593685\n ],\n [\n -90.41748046874999,\n 37.579412513438385\n ],\n [\n -93.779296875,\n 37.63163475580643\n ],\n [\n -93.91113281249999,\n 37.23032838760387\n ],\n [\n -96.56982421875,\n 37.35269280367274\n ],\n [\n -96.61376953125,\n 36.932330061503144\n ],\n [\n -102.01904296874999,\n 37.00255267215955\n ],\n [\n -102.10693359375,\n 40.979898069620155\n ],\n [\n -103.73291015625,\n 41.02964338716638\n ],\n [\n -103.68896484375,\n 41.590796851056005\n ],\n [\n -104.08447265624999,\n 41.590796851056005\n ],\n [\n -104.1064453125,\n 42.08191667830631\n ],\n [\n -103.447265625,\n 42.17968819665961\n ],\n [\n -103.4033203125,\n 42.956422511073335\n ],\n [\n -103.99658203125,\n 43.004647127794435\n ],\n [\n -104.1064453125,\n 43.42100882994726\n ],\n [\n -102.7880859375,\n 43.46886761482925\n ],\n [\n -102.67822265625,\n 43.004647127794435\n ],\n [\n -101.53564453124999,\n 43.08493742707592\n ],\n [\n -101.689453125,\n 43.46886761482925\n ],\n [\n -102.26074218749999,\n 43.97700467496408\n ],\n [\n -102.26074218749999,\n 44.18220395771566\n ],\n [\n -104.0625,\n 44.37098696297173\n ],\n [\n -104.0185546875,\n 45.30580259943578\n ],\n [\n -103.20556640625,\n 45.321254361171476\n ],\n [\n -103.1396484375,\n 45.935870621190546\n ],\n [\n -100.5029296875,\n 45.9511496866914\n ],\n [\n -100.72265625,\n 46.13417004624326\n ],\n [\n -100.61279296875,\n 46.255846818480336\n ],\n [\n -100.56884765624999,\n 46.49839225859763\n ],\n [\n -100.8984375,\n 46.7549166192819\n ],\n [\n -100.87646484375,\n 47.14489748555398\n ],\n [\n -101.00830078125,\n 47.26432008025478\n ],\n [\n -100.2392578125,\n 47.368594345213374\n ],\n [\n -100.1953125,\n 47.87214396888731\n ],\n [\n -98.525390625,\n 47.857402894658236\n ],\n [\n -98.54736328125,\n 48.58932584966972\n ],\n [\n -98.23974609375,\n 48.647427805533546\n ],\n [\n -98.23974609375,\n 48.951366470947725\n ],\n [\n -97.20703125,\n 49.03786794532644\n ],\n [\n -97.119140625,\n 48.777912755501845\n ],\n [\n -97.1630859375,\n 48.58932584966972\n ],\n [\n -95.69091796875,\n 48.48748647988415\n ],\n [\n -95.537109375,\n 47.87214396888731\n ],\n [\n -93.40576171875,\n 47.84265762816535\n ],\n [\n -93.14208984375,\n 47.84265762816535\n ],\n [\n -92.96630859375,\n 46.392411189814645\n ],\n [\n -92.30712890625,\n 46.37725420510028\n ],\n [\n -92.28515625,\n 46.11894150610708\n ],\n [\n -90.90087890624999,\n 46.08847179577592\n ],\n [\n -90.46142578125,\n 45.920587344733654\n ],\n [\n -90.439453125,\n 45.5679096098613\n ],\n [\n -88.48388671874999,\n 45.38301927899065\n ],\n [\n -88.35205078124999,\n 45.66012730272194\n ],\n [\n -88.0224609375,\n 45.75219336063106\n ],\n [\n -87.802734375,\n 45.73685954736049\n ],\n [\n -87.86865234374999,\n 45.398449976304086\n ],\n [\n -87.64892578125,\n 45.460130637921004\n ],\n [\n -87.6708984375,\n 45.213003555993964\n ],\n [\n -87.51708984375,\n 45.089035564831036\n ],\n [\n -87.6708984375,\n 44.933696389694674\n ],\n [\n -88.0224609375,\n 44.55916341529184\n ],\n [\n -87.4951171875,\n 44.87144275016589\n ],\n [\n -86.90185546874999,\n 45.460130637921004\n ],\n [\n -87.29736328125,\n 44.69989765840318\n ],\n [\n -87.56103515625,\n 44.213709909702054\n ],\n [\n -87.69287109375,\n 43.94537239244209\n ],\n [\n -87.73681640625,\n 43.6599240747891\n ],\n [\n -87.91259765625,\n 43.26120612479979\n ],\n [\n -87.802734375,\n 42.74701217318067\n ],\n [\n -87.802734375,\n 42.309815415686664\n ],\n [\n -87.62695312499999,\n 42.06560675405716\n ],\n [\n -87.51708984375,\n 41.72213058512578\n ],\n [\n -87.12158203125,\n 41.68932225997044\n ],\n [\n -86.55029296875,\n 42.06560675405716\n ],\n [\n -86.220703125,\n 42.569264372193864\n ],\n [\n -86.2646484375,\n 43.11702412135048\n ],\n [\n -86.5283203125,\n 43.50075243569041\n ],\n [\n -86.4404296875,\n 43.8186748554532\n ],\n [\n -86.59423828125,\n 44.10336537791152\n ],\n [\n -86.28662109375,\n 44.35527821160296\n ],\n [\n -86.220703125,\n 44.77793589631623\n ],\n [\n -85.62744140625,\n 45.182036837015886\n ],\n [\n -85.53955078125,\n 44.809121700077355\n ],\n [\n -85.25390625,\n 45.089035564831036\n ],\n [\n -85.341796875,\n 45.35214524585177\n ],\n [\n -85.01220703125,\n 45.42929873257377\n ],\n [\n -85.10009765625,\n 45.598665689820656\n ],\n [\n -84.8583984375,\n 45.73685954736049\n ],\n [\n -84.462890625,\n 45.67548217560647\n ],\n [\n -84.08935546875,\n 45.598665689820656\n ],\n [\n -83.29833984375,\n 44.43377984606825\n ],\n [\n -83.43017578125,\n 44.29240108529005\n ],\n [\n -83.6279296875,\n 44.05601169578525\n ],\n [\n -83.84765625,\n 43.929549935614595\n ],\n [\n -83.8037109375,\n 43.691707903073805\n ],\n [\n -83.64990234375,\n 43.61221676817573\n ],\n [\n -83.27636718749999,\n 43.992814500489914\n ],\n [\n -82.99072265625,\n 44.05601169578525\n ],\n [\n -82.63916015625,\n 43.866218006556394\n ],\n [\n -82.50732421875,\n 43.389081939117496\n ],\n [\n -82.41943359375,\n 42.97250158602597\n ],\n [\n -82.55126953124999,\n 42.601619944327965\n ],\n [\n -82.880859375,\n 42.391008609205045\n ],\n [\n -83.12255859375,\n 42.17968819665961\n ],\n [\n -83.1884765625,\n 41.918628865183045\n ],\n [\n -83.43017578125,\n 41.75492216766298\n ],\n [\n -82.6611328125,\n 41.409775832009565\n ],\n [\n -82.0458984375,\n 41.52502957323801\n ],\n [\n -81.6943359375,\n 41.52502957323801\n ],\n [\n -81.1669921875,\n 41.80407814427237\n ],\n [\n -80.5517578125,\n 41.934976500546604\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"30","issue":"5","noUsgsAuthors":false,"publicationDate":"1996-04-25","publicationStatus":"PW","scienceBaseUri":"5059e68ee4b0c8380cd474c7","contributors":{"authors":[{"text":"Kolpin, D.W.","contributorId":87565,"corporation":false,"usgs":true,"family":"Kolpin","given":"D.W.","email":"","affiliations":[],"preferred":false,"id":380817,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Nations, B.K.","contributorId":67667,"corporation":false,"usgs":true,"family":"Nations","given":"B.K.","email":"","affiliations":[],"preferred":false,"id":380816,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Goolsby, D. A.","contributorId":50508,"corporation":false,"usgs":true,"family":"Goolsby","given":"D.","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":380815,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Thurman, E.M.","contributorId":102864,"corporation":false,"usgs":true,"family":"Thurman","given":"E.M.","affiliations":[],"preferred":false,"id":380818,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70018798,"text":"70018798 - 1996 - Distributions and fate of chlorinated pesticides, biomarkers and polycyclic aromatic hydrocarbons in sediments along a contamination gradient from a point-source in San Francisco Bay, California","interactions":[],"lastModifiedDate":"2019-02-22T07:05:40","indexId":"70018798","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","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":"Distributions and fate of chlorinated pesticides, biomarkers and polycyclic aromatic hydrocarbons in sediments along a contamination gradient from a point-source in San Francisco Bay, California","docAbstract":"The distribution and fate of chlorinated pesticides, biomarkers, and polycyclic aromatic hydrocarbons (PAHs) in surficial sediments along a contamination gradient in the Lauritzen Canal and Richmond Harbor in San Francisco Bay was investigated. Compounds were identified and quantified using gas chromatography-ion trap mass spectrometry. Biomarkers and PAHs were derived primarily from weathered petroleum. DDT was reductively dechlorinated under anoxic conditions to DDD and several minor degradation products, DDMU, DDMS, and DDNU. Under aerobic conditions, DDT was dehydrochlorinated to DDE and DBP. Aerobic degradation of DDT was diminished or inhibited in zones of high concentration, and increased significantly in zones of lower concentration: Other chlorinated pesticides identified in sediment included dieldrin and chlordane isomers. Multivariate analysis of the distributions of the DDTs suggested that there are probably two sources of DDD. In addition, DDE and DDMU are probably formed by similar mechanisms, i.e. dehydrochlorination. A steep concentration gradient existed from the Canal to the Outer Richmond Harbor, but higher levels of DDD than those found in the remainder of the Bay indicated that these contaminants are transported on particulates and colloidal organic matter from this source into San Francisco Bay. Chlorinated pesticides and PAHs may pose a potential problem to biota in San Francisco Bay.
","language":"English","publisher":"Elsevier","doi":"10.1016/0141-1136(95)00021-6","issn":"01411136","usgsCitation":"Pereira, W.E., Hostettler, F., and Rapp, J.B., 1996, Distributions and fate of chlorinated pesticides, biomarkers and polycyclic aromatic hydrocarbons in sediments along a contamination gradient from a point-source in San Francisco Bay, California: Marine Environmental Research, v. 41, no. 3, p. 299-314, https://doi.org/10.1016/0141-1136(95)00021-6.","productDescription":"16 p.","startPage":"299","endPage":"314","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true},{"id":552,"text":"San Francisco Bay-Delta","active":false,"usgs":true},{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true},{"id":5079,"text":"Pacific Regional Director's Office","active":true,"usgs":true}],"links":[{"id":227628,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":205958,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/0141-1136(95)00021-6"}],"volume":"41","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a0328e4b0c8380cd5037f","contributors":{"authors":[{"text":"Pereira, W. E.","contributorId":46981,"corporation":false,"usgs":true,"family":"Pereira","given":"W.","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":380787,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Hostettler, F. D.","contributorId":99563,"corporation":false,"usgs":true,"family":"Hostettler","given":"F. D.","affiliations":[],"preferred":false,"id":380788,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Rapp, J. B.","contributorId":28987,"corporation":false,"usgs":true,"family":"Rapp","given":"J.","email":"","middleInitial":"B.","affiliations":[],"preferred":false,"id":380786,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70018782,"text":"70018782 - 1996 - Simulation of phosphate transport in sewage-contaminated groundwater, Cape Cod, Massachusetts","interactions":[],"lastModifiedDate":"2019-02-20T08:40:17","indexId":"70018782","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":835,"text":"Applied Geochemistry","active":true,"publicationSubtype":{"id":10}},"title":"Simulation of phosphate transport in sewage-contaminated groundwater, Cape Cod, Massachusetts","docAbstract":"Sewage-contaminated groundwater currently discharges to Ashumet Pond, located on Cape Cod, Massachusetts. Phosphate concentrations as high as 60 μmol l−1 have been measured in groundwater entering Ashumet Pond, and there is concern that the rate of eutrophication could increase. Phosphate in the sewage plume is sorbed by aquifer sediment; the amount is a function of phosphate concentration and pH. A nonelectrostatic surface-complexation model coupled with a one-dimensional solute-transport code was used to simulate sorption and desorption of phosphate in laboratory column experiments. The model simulated sorption of phosphate reasonably well, although the slow rate of approach to complete breakthrough indicated a nonequilibrium process that was not accounted for in the solute-transport model. The rate of phosphate desorption in the column experiments was relatively slow. Phosphate could still be measured in effluent after 160 pore volumes of uncontaminated groundwater had been flushed through the columns. Desorption was partly a function of the slowly decreasing pH in the columns and could be modeled quantitatively. Disposal of sewage at this site is scheduled to stop in 1995; however, a large reservoir of sorbed phosphate exists on aquifer sediment upgradient from Ashumet Pond. Computer simulations predict that desorption of phosphate could result in contamination of Ashumet Pond for decades.
In the past, ice-core records from mid-latitude glaciers in alpine areas of the continental United States were considered to be poor candidates for paleoclimate records because of the influence of meltwater on isotopic stratigraphy. To evaluate the existence of reliable paleoclimatic records, a 160-m ice core, containing about 250 yr of record was obtained from Upper Fremont Glacier, at an altitude of 4000 m in the Wind River Range of south-central North America. The δ18O (SMOW) profile from the core shows a -0.95‰ shift to lighter values in the interval from 101.8 to 150 m below the surface, corresponding to the latter part of the Little Ice Age (LIA). Numerous high-amplitude oscillations in the section of the core from 101.8 to 150 m cannot be explained by site-specific lateral variability and probably reflect increased seasonality or better preservation of annual signals as a result of prolonged cooler temperatures that existed in this alpine setting. An abrupt decrease in these large amplitude oscillations at the 101.8-m depth suggests a sudden termination of this period of lower temperatures which generally coincides with the termination of the LIA. Three common features in the δ18O profiles between Upper Fremont Glacier and the better dated Quelccaya Ice Cap cores indicate a global paleoclimate linkage, further supporting the first documented occurrence of the LIA in an ice-core record from a temperate glacier in south-central North America.
","language":"English","publisher":"INSTAAR, University of Colorado","doi":"10.2307/1552083","issn":"00040851","usgsCitation":"Naftz, D.L., Klusman, R., Michel, R.L., Schuster, P., Ready, M., Taylor, H.E., Yanosky, T., and McConnaughey, E., 1996, Little Ice Age evidence from a south-central North American ice core, U.S.A.: Arctic and Alpine Research, v. 28, no. 1, p. 35-41, https://doi.org/10.2307/1552083.","productDescription":"7 p.","startPage":"35","endPage":"41","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":227402,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","otherGeospatial":"Upper Fremont Glacier, Wind River Range","volume":"28","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a48b1e4b0c8380cd68066","contributors":{"authors":[{"text":"Naftz, D. L.","contributorId":40624,"corporation":false,"usgs":true,"family":"Naftz","given":"D.","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":380734,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Klusman, R.W.","contributorId":93108,"corporation":false,"usgs":true,"family":"Klusman","given":"R.W.","email":"","affiliations":[],"preferred":false,"id":380738,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Michel, R. L.","contributorId":86375,"corporation":false,"usgs":true,"family":"Michel","given":"R.","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":380737,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Schuster, P. F.","contributorId":30197,"corporation":false,"usgs":true,"family":"Schuster","given":"P. F.","affiliations":[],"preferred":false,"id":380732,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Ready, M.M.","contributorId":63968,"corporation":false,"usgs":true,"family":"Ready","given":"M.M.","email":"","affiliations":[],"preferred":false,"id":380736,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Taylor, Howard E. hetaylor@usgs.gov","contributorId":1551,"corporation":false,"usgs":true,"family":"Taylor","given":"Howard","email":"hetaylor@usgs.gov","middleInitial":"E.","affiliations":[{"id":5044,"text":"National Research Program - Central Branch","active":true,"usgs":true}],"preferred":true,"id":380733,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Yanosky, T.M.","contributorId":42263,"corporation":false,"usgs":true,"family":"Yanosky","given":"T.M.","email":"","affiliations":[],"preferred":false,"id":380735,"contributorType":{"id":1,"text":"Authors"},"rank":7},{"text":"McConnaughey, E.A.","contributorId":97265,"corporation":false,"usgs":true,"family":"McConnaughey","given":"E.A.","email":"","affiliations":[],"preferred":false,"id":380739,"contributorType":{"id":1,"text":"Authors"},"rank":8}]}} ,{"id":70018769,"text":"70018769 - 1996 - Processes affecting the fate of monoaromatic hydrocarbons in an aquifer contaminated by crude oil","interactions":[],"lastModifiedDate":"2019-02-20T09:54:36","indexId":"70018769","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","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":"Processes affecting the fate of monoaromatic hydrocarbons in an aquifer contaminated by crude oil","docAbstract":"Crude oil spilled from a subsurface pipeline in north-central Minnesota has dissolved in the groundwater, resulting in the formation of a plume of aliphatic, aromatic, and alicyclic hydrocarbons. Comparison of paired oil and groundwater samples collected along the central axis of the residual oil body shows that the trailing edge of the oil is depleted in the more soluble aromatic hydrocarbons (e.g., benzene, toluene, etc.) when compared with the leading edge. At the same time, concentrations of monoaromatic hydrocarbons in groundwater beneath the oil increase as the water moves toward the leading edge of the oil. Immediately downgradient from the leading edge of the oil body, certain aromatic hydrocarbons (e.g., benzene) are found at concentrations near those expected of a system at equilibrium, and the concentrations exhibit little variation over time (???8-20%). Other compounds (e.g., toluene) appear to be undersaturated, and their concentrations show considerably more temporal variation (???20-130%). The former are persistent within the anoxic zone downgradient from the oil, whereas concentrations of the latter decrease rapidly. Together, these observations suggest that the volatile hydrocarbon composition of the anoxic groundwater near the oil body is controlled by a balance between dissolution and removal rates with only the most persistent compounds reaching saturation. Examination of the distributions of homologous series and isomeric assemblages of alkylbenzenes reveals that microbial degradation is the dominant process controlling the fate of these compounds once groundwater moves away from the oil. For all but the most persistent compounds, the distal boundary of the plume at the water table extends no more than 10-15 m down-gradient from the oxic/anoxic transition zone. Thus, transport of the monoaromatic hydrocarbons is limited by redox conditions that are tightly coupled to biological degradation processes.","language":"English","publisher":"ACS","doi":"10.1021/es960073b","issn":"0013936X","usgsCitation":"Eganhouse, R., Dorsey, T., Phinney, C., and Westcott, A., 1996, Processes affecting the fate of monoaromatic hydrocarbons in an aquifer contaminated by crude oil: Environmental Science & Technology, v. 30, no. 11, p. 3304-3312, https://doi.org/10.1021/es960073b.","productDescription":"9 p.","startPage":"3304","endPage":"3312","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":227270,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":205881,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1021/es960073b"}],"volume":"30","issue":"11","noUsgsAuthors":false,"publicationDate":"1996-10-29","publicationStatus":"PW","scienceBaseUri":"505a8da9e4b0c8380cd7ed5a","contributors":{"authors":[{"text":"Eganhouse, R.P.","contributorId":67555,"corporation":false,"usgs":true,"family":"Eganhouse","given":"R.P.","email":"","affiliations":[],"preferred":false,"id":380703,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Dorsey, T.F.","contributorId":34278,"corporation":false,"usgs":true,"family":"Dorsey","given":"T.F.","email":"","affiliations":[],"preferred":false,"id":380700,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Phinney, C.S.","contributorId":50302,"corporation":false,"usgs":true,"family":"Phinney","given":"C.S.","email":"","affiliations":[],"preferred":false,"id":380702,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Westcott, A.M.","contributorId":37484,"corporation":false,"usgs":true,"family":"Westcott","given":"A.M.","email":"","affiliations":[],"preferred":false,"id":380701,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70018760,"text":"70018760 - 1996 - Identification of a new sulfonic acid metabolite of metolachlor in soil","interactions":[],"lastModifiedDate":"2019-02-19T06:14:03","indexId":"70018760","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","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":"Identification of a new sulfonic acid metabolite of metolachlor in soil","docAbstract":"An ethanesulfonic acid metabolite of metolachlor (metolachlor ESA) was identified in soil-sample extracts by negative-ion, fast-atom bombardment mass spectrometry (FAB-MS) and FAB tandem mass spectrometry (FAB-MS/MS). Production fragments from MS/MS analysis of the deprotonated molecular ion of metolachlor ESA in the soil extract can be reconciled with the structure of the synthesized standard. The elemental compositions of the (M - H)- ions of the metolachlor ESA standard and the soil-sample extracts were confirmed by high-resolution mass spectrometry. A dissipation study revealed that metolachlor ESA is formed in soil under field conditions corresponding to a decrease in the concentration of the parent herbicide, metolachlor. The identification of the sulfonated metabolite of metolachlor suggests that the glutathione conjugation pathway is a common detoxification pathway shared by chloroacetanilide herbicides.","language":"English","publisher":"ACS","doi":"10.1021/es9503600","issn":"0013936X","usgsCitation":"Aga, D., Thurman, E., Yockel, M., Zimmerman, L., and Williams, T., 1996, Identification of a new sulfonic acid metabolite of metolachlor in soil: Environmental Science & Technology, v. 30, no. 2, p. 592-597, https://doi.org/10.1021/es9503600.","productDescription":"6 p.","startPage":"592","endPage":"597","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":227090,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":205847,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1021/es9503600"}],"volume":"30","issue":"2","noUsgsAuthors":false,"publicationDate":"1996-01-29","publicationStatus":"PW","scienceBaseUri":"505a381fe4b0c8380cd6144e","contributors":{"authors":[{"text":"Aga, D.S.","contributorId":18521,"corporation":false,"usgs":true,"family":"Aga","given":"D.S.","affiliations":[],"preferred":false,"id":380674,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Thurman, E.M.","contributorId":102864,"corporation":false,"usgs":true,"family":"Thurman","given":"E.M.","affiliations":[],"preferred":false,"id":380678,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Yockel, M.E.","contributorId":72943,"corporation":false,"usgs":true,"family":"Yockel","given":"M.E.","email":"","affiliations":[],"preferred":false,"id":380677,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Zimmerman, L.R.","contributorId":28624,"corporation":false,"usgs":true,"family":"Zimmerman","given":"L.R.","email":"","affiliations":[],"preferred":false,"id":380675,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Williams, T.D.","contributorId":53968,"corporation":false,"usgs":false,"family":"Williams","given":"T.D.","email":"","affiliations":[{"id":6953,"text":"Monterey Bay Aquarium","active":true,"usgs":false}],"preferred":false,"id":380676,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":70018747,"text":"70018747 - 1996 - Bacterial dissimilatory reduction of arsenic(V) to arsenic(III) in anoxic sediments","interactions":[],"lastModifiedDate":"2023-01-17T18:22:31.733039","indexId":"70018747","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":850,"text":"Applied and Environmental Microbiology","active":true,"publicationSubtype":{"id":10}},"title":"Bacterial dissimilatory reduction of arsenic(V) to arsenic(III) in anoxic sediments","docAbstract":"Incubation of anoxic salt marsh sediment slurries with 10 mM As(V) resulted in the disappearance over time of the As(V) in conjunction with its recovery as As(III). No As(V) reduction to As(III) occurred in heat- sterilized or formalin-killed controls or in live sediments incubated in air. The rate of As(V) reduction in slurries was enhanced by addition of the electron donor lactate, H2, or glucose, whereas the respiratory inhibitor/uncoupler dinitrophenol, rotenone, or 2-heptyl-4-hydroxyquinoline N-oxide blocked As(V) reduction. As(V) reduction was also inhibited by tungstate but not by molybdate, sulfate, or phosphate. Nitrate inhibited As(V) reduction by its action as a preferred respiratory electron acceptor rather than as a structural analog of As(V). Nitrate-respiring sediments could reduce As(V) to As(III) once all the nitrate was removed. Chloramphenicol blocked the reduction of As(V) to As(III) in nitrate- respiring sediments, suggesting that nitrate and arsenate were reduced by separate enzyme systems. Oxidation of [2-14C]acetate to 14CO2 by salt marsh and freshwater sediments was coupled to As(V). Collectively, these results show that reduction of As(V) in sediments proceeds by a dissimilatory process. Bacterial sulfate reduction was completely inhibited by As(V) as well as by As(III).
","language":"English","publisher":"American Society for Microbiology","doi":"10.1128/aem.62.5.1664-1669.1996","issn":"00992240","usgsCitation":"Dowdle, P., Laverman, A., and Oremland, R., 1996, Bacterial dissimilatory reduction of arsenic(V) to arsenic(III) in anoxic sediments: Applied and Environmental Microbiology, v. 62, no. 5, p. 1664-1669, https://doi.org/10.1128/aem.62.5.1664-1669.1996.","productDescription":"6 p.","startPage":"1664","endPage":"1669","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":479063,"rank":2,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1128/aem.62.5.1664-1669.1996","text":"Publisher Index Page"},{"id":227625,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"California, Nevada","city":"Palo Alto","otherGeospatial":"Lahontan Reservoir, San Francisco Bay","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -122.18074022293001,\n 37.486952872013276\n ],\n [\n -122.12718187332061,\n 37.45098427129997\n ],\n [\n -122.08289323806696,\n 37.413634924164086\n ],\n [\n -122.03860460281297,\n 37.42372381099733\n ],\n [\n -122.04890428543015,\n 37.46542828886591\n ],\n [\n -122.08289323806696,\n 37.50356887782067\n ],\n [\n -122.0942228889459,\n 37.518547352838866\n ],\n [\n -122.10383592605513,\n 37.533250567381344\n ],\n [\n -122.18074022293001,\n 37.486952872013276\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n },\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -119.1345078593209,\n 39.32525855997096\n ],\n [\n -119.09021922406694,\n 39.34384676341648\n ],\n [\n -119.08472606000439,\n 39.36349177591711\n ],\n [\n -119.11013194379368,\n 39.36561523018946\n ],\n [\n -119.1726166850044,\n 39.39003031367665\n ],\n [\n -119.16437693891072,\n 39.39878581707654\n ],\n [\n -119.10086222943792,\n 39.39507149528393\n ],\n [\n -119.08369609174261,\n 39.408070756315965\n ],\n [\n -119.08438273725056,\n 39.41815014789276\n ],\n [\n -119.06447001752414,\n 39.43247098706226\n ],\n [\n -119.05485698041457,\n 39.431940638090424\n ],\n [\n -119.03975077924278,\n 39.4401605934836\n ],\n [\n -119.06755992230907,\n 39.46879028124664\n ],\n [\n -119.08026286420355,\n 39.46269420482139\n ],\n [\n -119.08781596478963,\n 39.45076555431987\n ],\n [\n -119.09742900189886,\n 39.44069087987978\n ],\n [\n -119.11768504437941,\n 39.41443685737025\n ],\n [\n -119.14961406049272,\n 39.41761968992745\n ],\n [\n -119.18497630414507,\n 39.427697700988375\n ],\n [\n -119.2090088969185,\n 39.41815014789276\n ],\n [\n -119.21003886518025,\n 39.40992759583173\n ],\n [\n -119.19939585980926,\n 39.40249994110201\n ],\n [\n -119.19973918256308,\n 39.39719398909571\n ],\n [\n -119.21690532025838,\n 39.3879076019268\n ],\n [\n -119.196305955024,\n 39.374108401648016\n ],\n [\n -119.18016978559046,\n 39.35924467368929\n ],\n [\n -119.16437693891072,\n 39.365349801935935\n ],\n [\n -119.15442057904733,\n 39.364022645537716\n ],\n [\n -119.14171763715285,\n 39.3542009043891\n ],\n [\n -119.14824076947716,\n 39.34278471349546\n ],\n [\n -119.1345078593209,\n 39.32525855997096\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","volume":"62","issue":"5","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059ef9ee4b0c8380cd4a362","contributors":{"authors":[{"text":"Dowdle, P.R.","contributorId":77678,"corporation":false,"usgs":true,"family":"Dowdle","given":"P.R.","email":"","affiliations":[],"preferred":false,"id":380642,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Laverman, A.M.","contributorId":8238,"corporation":false,"usgs":true,"family":"Laverman","given":"A.M.","affiliations":[],"preferred":false,"id":380641,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Oremland, R.S.","contributorId":97512,"corporation":false,"usgs":true,"family":"Oremland","given":"R.S.","email":"","affiliations":[],"preferred":false,"id":380643,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70018738,"text":"70018738 - 1996 - Copper speciation and binding by organic matter in copper-contaminated streamwater","interactions":[],"lastModifiedDate":"2019-02-20T09:18:13","indexId":"70018738","displayToPublicDate":"1996-01-01T00:00:00","publicationYear":"1996","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":"Copper speciation and binding by organic matter in copper-contaminated streamwater","docAbstract":"Fulvic acid binding sites (1.3−70 μM) and EDTA (0.0017−0.18 μM) accounted for organically bound Cu in seven stream samples measured by potentiometric titration. Cu was 84−99% organically bound in filtrates with 200 nM total Cu. Binding of Cu by EDTA was limited by competition from other trace metals. Water hardness was inversely related to properties of dissolved organic carbon (DOC) that enhance fulvic acid binding: DOC concentration, percentage of DOC that is fulvic acid, and binding sites per fulvic acid carbon. Dissolved trace metals, stabilized by organic binding, occurred at increased concentration in soft water as compared to hard water.