Permeability of continental crust influenced by internal and external forcing
S.A. Rojstaczer, S. E. Ingebritsen, D.O. Hayba
2008, Geofluids (8) 128-139
The permeability of continental crust is so highly variable that it is often considered to defy systematic characterization. However, despite this variability, some order has been gleaned from globally compiled data. What accounts for the apparent coherence of mean permeability in the continental crust (and permeability–depth relations) on a very...
Pathogen and chemical transport in the karst limestone of the Biscayne aquifer: 1. Revised conceptualization of groundwater flow
Robert A. Renken, Kevin J. Cunningham, Allen M. Shapiro, Ronald W. Harvey, Michael R. Zygnerski, David W. Metge, Michael A. Wacker
2008, Water Resources Research (44)
The Biscayne aquifer is a highly transmissive karst limestone that serves as the sole source of drinking water to over two million residents in south Florida. The aquifer is characterized by eogenetic karst, where the most transmissive void space can be an interconnected, touching‐vug, biogenically influenced porosity of biogenic origin....
Passive microwave (SSM/I) satellite predictions of valley glacier hydrology, Matanuska Glacier, Alaska
S.E. Kopczynski, J. Ramage, D. Lawson, S. Goetz, E. Evenson, J. Denner, G. Larson
2008, Geophysical Research Letters (35)
We advance an approach to use satellite passive microwave observations to track valley glacier snowmelt and predict timing of spring snowmelt-induced floods at the terminus. Using 37 V GHz brightness temperatures (Tb) from the Special Sensor Microwave hnager (SSM/I), we monitor snowmelt onset when both Tb and the difference between...
Evaporite-karst problems and studies in the USA
K.S. Johnson
2008, Conference Paper, Environmental Geology
Evaporites, including rock salt (halite) and gypsum (or anhydrite), are the most soluble among common rocks; they dissolve readily to form the same types of karst features that commonly are found in limestones and dolomites. Evaporites are present in 32 of the 48 contiguous states in USA, and they underlie...
Susceptibility to enhanced chemical migration from depression-focused preferential flow, High Plains aquifer
Jason J. Gurdak, Michelle Ann Walvoord, Peter B. McMahon
2008, Vadose Zone Journal (7) 1172-1184
Aquifer susceptibility to contamination is controlled in part by the inherent hydrogeologic properties of the vadose zone, which includes preferential-flow pathways. The purpose of this study was to investigate the importance of seasonal ponding near leaky irrigation wells as a mechanism for depression-focused preferential flow and enhanced chemical migration through...
Understanding the relationship between audiomagnetotelluric data and models, and borehole data in a hydrological environment
D.K. McPhee, L. Pellerin
2008, Conference Paper, SEG Technical Program Expanded Abstracts
Audiomagnetotelluric (AMT) data and resulting models are analyzed with respect to geophysical and geological borehole logs in order to clarify the relationship between the two methodologies of investigation of a hydrological environment. Several profiles of AMT data collected in basins in southwestern United States are being used for groundwater exploration...
Transport and fate of nitrate at the ground-water/surface-water interface
L.J. Puckett, C. Zamora, H. Essaid, J.T. Wilson, H.M. Johnson, M.J. Brayton, J. R. Vogel
2008, Journal of Environmental Quality (37) 1034-1050
Although numerous studies of hyporheic exchange and denitrification have been conducted in pristine, high-gradient streams, few studies of this type have been conducted in nutrient-rich, low-gradient streams. This is a particularly important subject given the interest in nitrogen (N) inputs to the Gulf of Mexico and other eutrophic aquatic systems....
Peat porewater chloride concentration profiles in the Everglades during wet/dry cycles from January 1996 to June 1998: Field measurements and theoretical analysis
M.M. Reddy, M.B. Reddy, K.L. Kipp, A. Burman, Peter Schuster, P.S. Rawlik Jr.
2008, Hydrological Processes (22) 1713-1724
Water quality is a key aspect of the Everglades Restoration Project, the largest water reclamation and ecosystem management project proposed in the United States. Movement of nutrients and contaminants to and from Everglades peat porewater could have important consequences for Everglades water quality and ecosystem restoration activities. In a study...
Differences in evaporation between a floating pan and class a pan on land
J.R. Masoner, D.I. Stannard, S. C. Christenson
2008, Journal of the American Water Resources Association (44) 552-561
Research was conducted to develop a method for obtaining floating pan evaporation rates in a small (less than 10,000 m2) wetland, lagoon, or pond. Floating pan and land pan evaporation data were collected from March 1 to August 31, 2005, at a small natural wetland located in the alluvium of the...
NMR and mass spectrometry of phosphorus in wetlands
H. El-Rifai, M. Heerboth, T.E. Gedris, S. Newman, W. Orem, W.T. Cooper
2008, European Journal of Soil Science (59) 517-525
There is at present little information on the long-term stability of phosphorus sequestered in wetlands. Phosphorus sequestered during high loading periods may be relatively unstable and easily remobilized following changes in nutrient status or hydrological regime, but the chemical forms of sequestered phosphorus that do remobilize are largely unknown at...
Low-Level detections of halogenated volatile organic compounds in groundwater: Use in vulnerability assessments
Niel Plummer, E. Busenberg, S. M. Eberts, L. M. Bexfield, C. J. Brown, L.S. Fahlquist, B. G. Katz, M.K. Landon
2008, Journal of Hydrologic Engineering (13) 1049-1068
Concentrations of halogenated volatile organic compounds (VOCs) were determined by gas chromatography (GC) with an electron-capture detector (GC-ECD) and by gas chromatography with mass spectrometry (GC-MS) in 109 groundwater samples from five study areas in the United States. In each case, the untreated water sample was used...
Reply to comment by J. Szilagyi on "Comparison of 15 evaporation methods applied to a small mountain lake in the northeastern USA" [J. Hydrol. 340 (3-4) (2007) 149-166]
D.O. Rosenberry, T. C. Winter, D.C. Buso, G.E. Likens
2008, Journal of Hydrology (348) 566-567
[No abstract available]...
Potential for 4-n-nonylphenol biodegradation in stream sediments
P. M. Bradley, L. B. Barber, D.W. Kolpin, P.B. McMahon, F. H. Chapelle
2008, Environmental Toxicology and Chemistry (27) 260-265
The potential for in situ biodegradation of 4-nonylphenol (4-NP) was investigated in three hydrologically distinct streams impacted by wastewater treatment plants (WWTPs) in the United States. Microcosms were prepared with sediments from each site and amended with [U-ring-14C]4-n-nonylphenol (4-n-NP) as a model test substrate. Microcosms prepared with sediment collected upstream...
Isotopic variations of dissolved copper and zinc in stream waters affected by historical mining
David M. Borrok, David Nimick, Richard B. Wanty, William I. Ridley
2008, Geochimica et Cosmochimica Acta (72) 329-344
Zinc and Cu play important roles in the biogeochemistry of natural systems, and it is likely that these interactions result in mass-dependent fractionations of their stable isotopes. In this study, we examine the relative abundances of dissolved Zn and Cu isotopes in a variety of stream waters draining six historical...
Subsurface microbial diversity in deep-granitic-fracture water in Colorado
J.W. Sahl, R. Schmidt, E.D. Swanner, K.W. Mandernack, A.S. Templeton, Thomas L. Kieft, R. L. Smith, W. E. Sanford, R.L. Callaghan, J.B. Mitton, J.R. Spear
2008, Applied and Environmental Microbiology (74) 143-152
A microbial community analysis using 16S rRNA gene sequencing was performed on borehole water and a granite rock core from Henderson Mine, a >1,000-meter-deep molybdenum mine near Empire, CO. Chemical analysis of borehole water at two separate depths (1,044 m and 1,004 m below the mine...
Evapotranspiration rates and crop coefficients for a restored marsh in the Sacramento-San Joaquin Delta, California, USA
Judith Z. Drexler, Frank E. Anderson, Richard L. Snyder
2008, Hydrological Processes (22) 725-735
The surface renewal method was used to estimate evapotranspiration (ET) for a restored marsh on Twitchell Island in the Sacramento–San Joaquin Delta, California, USA. ET estimates for the marsh, together with reference ET measurements from a nearby climate station, were used to determine crop coefficients over a 3‐year period during...
Chromium, chromium isotopes and selected trace elements, western Mojave Desert, USA
J. A. Izbicki, J.W. Ball, T.D. Bullen, S. J. Sutley
2008, Applied Geochemistry (23) 1325-1352
Chromium(VI) concentrations in excess of the California Maximum Contaminant Level (MCL) of 50 μg/L occur naturally in alkaline, oxic ground-water in alluvial aquifers in the western Mojave Desert, southern California. The highest concentrations were measured in aquifers eroded from mafic rock, but Cr(VI)...
Pathogen and chemical transport in the karst limestone of the Biscayne aquifer: 2. Chemical retention from diffusion and slow advection
Allen M. Shapiro, Robert A. Renken, Ronald W. Harvey, Michael R. Zygnerski, David W. Metge
2008, Water Resources Research (44)
A tracer experiment, using a nonreactive tracer, was conducted as part of an investigation of the potential for chemical and pathogen migration to public supply wells that draw groundwater from the highly transmissive karst limestone of the Biscayne aquifer in southeastern Florida. The tracer was injected into the formation over...
Influence of variable chemical conditions on EDTA-enhanced transport of metal ions in mildly acidic groundwater
D.B. Kent, J.A. Davis, J.L. Joye, G.P. Curtis
2008, Environmental Pollution (153) 44-52
Adsorption of Ni and Pb on aquifer sediments from Cape Cod, Massachusetts, USA increased with increasing pH and metal-ion concentration. Adsorption could be described quantitatively using a semi-mechanistic surface complexation model (SCM), in which adsorption is described using chemical reactions between metal ions and adsorption sites. Equilibrium reactive transport simulations...
Concentrations and environmental fate of Ra in cation-exchange regeneration brine waste disposed to septic tanks and accumulation in sludge, New Jersey Coastal Plain, USA
Z. Szabo, E. Jacobsen, T. F. Kraemer, B. Parsa
2008, Journal of Environmental Radioactivity (99) 947-964
Concentrations of Ra in liquid and solid wastes generated from 15 softeners treating domestic well waters from New Jersey Coastal Plain aquifers (where combined Ra (226Ra plus 228Ra) concentrations commonly exceed 0.185 Bq L−1) were determined. Softeners, when maintained, reduced combined Ra about 10-fold (<0.024 Bq L−1). Combined...
Changes in the character of DOC in streams during storms in two Midwestern watersheds with contrasting land uses
P. Vidon, L.E. Wagner, E. Soyeux
2008, Biogeochemistry (88) 257-270
Dissolved organic carbon (DOC) dynamics in streams is important, yet few studies focus on DOC dynamics in Midwestern streams during storms. In this study, stream DOC dynamics during storms in two Midwestern watersheds with contrasting land uses, the change in character of stream DOC during storms, and the usability of...
Investigation and hazard assessment of the 2003 and 2007 Staircase Falls rock falls, Yosemite National Park, California, USA
G. F. Wieczorek, Gregory M. Stock, P. Reichenbach, J.B. Snyder, J. W. Borchers, J. W. Godt
2008, Natural Hazards and Earth System Sciences (8) 421-432
Since 1857 more than 600 rock falls, rock slides, debris slides, and debris flows have been documented in Yosemite National Park, with rock falls in Yosemite Valley representing the majority of the events. On 26 December 2003, a rock fall originating from west of Glacier Point sent approximately 200 m...
Soil slip/debris flow localized by site attributes and wind-driven rain in the San Francisco Bay region storm of January 1982
R.J. Pike, S. Sobieszczyk
2008, Geomorphology (94) 290-313
GIS analysis at 30-m resolution reveals that effectiveness of slope-destabilizing processes in the San Francisco Bay area varies with compass direction. Nearly half the soil slip/debris flows mapped after the catastrophic rainstorm of 3-5 January 1982 occurred on slopes that face S to WSW, whereas fewer than one-quarter have a...
Characterization of errors in a coupled snow hydrology-microwave emission model
K.M. Andreadis, D. Liang, L. Tsang, D.P. Lettenmaier, E.G. Josberger
2008, Journal of Hydrometeorology (9) 149-164
Traditional approaches to the direct estimation of snow properties from passive microwave remote sensing have been plagued by limitations such as the tendency of estimates to saturate for moderately deep snowpacks and the effects of mixed land cover within remotely sensed pixels. An alternative approach is to assimilate satellite microwave...
A multi-residue method for the analysis of pesticides and pesticide degradates in water using HLB solid-phase extraction and gas chromatography-ion trap mass spectrometry
M.L. Hladik, K.L. Smalling, K.M. Kuivila
2008, Bulletin of Environmental Contamination and Toxicology (80) 139-144
A method was developed for the analysis of over 60 pesticides and degradates in water by HLB solid-phase extraction and gas-chromatography/mass spectrometry. Method recoveries and detection limits were determined using two surface waters with different dissolved organic carbon (DOC) concentrations. In the lower DOC water, recoveries and detection limits...
