High-pressure size exclusion chromatography analysis of dissolved organic matter isolated by tangential-flow ultra filtration
C.R. Everett, Y.-P. Chin, G. R. Aiken
1999, Limnology and Oceanography (44) 1316-1322
A 1,000-Dalton tangential-flow ultrafiltration (TFUF) membrane was used to isolate dissolved organic matter (DOM) from several freshwater environments. The TFUF unit used in this study was able to completely retain a polystyrene sulfonate 1,800-Dalton standard. Unaltered and TFUF-fractionated DOM molecular weights were assayed by high-pressure size exclusion chromatography (HPSEC). The...
Prediction of episodic acidification in North-eastern USA: An empirical/mechanistic approach
T.D. Davies, M. Tranter, P.J. Wigington Jr., K.N. Eshleman, N.E. Peters, J. Van Sickle, David R. DeWalle, Peter S. Murdoch
1999, Hydrological Processes (13) 1181-1195
Observations from the US Environmental Protection Agency's Episodic Response Project (ERP) in the North-eastern United States are used to develop an empirical/mechanistic scheme for prediction of the minimum values of acid neutralizing capacity (ANC) during episodes. An acidification episode is defined as a hydrological event during which ANC decreases. The...
Are shifts in herbicide use reflected in concentration changes in Midwestern rivers?
W.A. Battaglin, D. A. Goolsby
1999, Environmental Science & Technology (33) 2917-2925
In many Midwestern rivers, elevated concentrations of herbicides occur during runoff events for 1-3 months following application. The highest or 'peak' herbicide concentration often occurs during one of these runoff events. Herbicide concentrations in rivers are affected by a number of factors, including herbicide use patterns within the associated basin....
Tritium and 14C concentrations in unsaturated-zone gases at test hole UZB-2, Amargosa Desert Research Site, 1994-98: A section in U.S. Geological Survey Toxic Substances Hydrology Program: Proceedings of the technical meeting, Charleston, South Carolina, March 8-12, 1999: Volume 3 (Part C) (WRI 99-4018C)>
David E. Prudic, Robert G. Striegl, Richard W. Healy, Robert L. Michel, Herbert Haas
David W. Morganwalp, Herbert T. Buxton, editor(s)
1999, Report, U.S. Geological Survey Toxic Substances Hydrology Program: Proceedings of the technical meeting, Charleston, South Carolina, March 8-12, 1999: Volume 3 (Part C) (WRI 99-4018C)
Tritium concentrations have been determined yearly since April 1994 from water-vapor samples collected at test hole UZB-2. The hole was drilled about 100 m (meters) south of the southwest corner of a commercial burial site for low-level radioactive wastes in September 1993. UZB-2 is equipped with ten 2.5-cm (centimeters) diameter...
Soil respiration at the Amargosa Desert Research site: A section in U.S. Geological Survey Toxic Substances Hydrology Program: Proceedings of the technical meeting, Charleston, South Carolina, March 8-12, 1999: Volume 3 (Part C) (WRI 99-4018C)
Alan C. Riggs, Robert G. Striegl, Florentino B. Maestas
David W. Morganwalp, Herbert T. Buxton, editor(s)
1999, Report, U.S. Geological Survey Toxic Substances Hydrology Program: Proceedings of the technical meeting, Charleston, South Carolina, March 8-12, 1999: Volume 3 (Part C) (WRI 99-4018C)
Automated opaque flux-chamber measurements of soil carbon dioxide (CO2) flux (soil respiration) into the atmosphere at the Amargosa Desert Research Site show seasonal and diel cycles of soil respiration that are closely linked with soil temperature and soil moisture. During 1998, soil respiration increased with soil warming through spring, reaching...
Wetlands of the Prairie Pothole Region: Invertebrate species composition, ecology, and management
N.H. Euliss Jr., D.A. Wrubleski, D.M. Mushet
D.P. Batzer, R.B. Rader, S.A. Wissinger, editor(s)
1999, Book chapter, Invertebrates in freshwater wetlands of North America: Ecology and management
The Prairie Pothole Region (PPR) of the United States and Canada is a unique area where shallow depressions created by the scouring action of Pleistocene glaciation interact with mid-continental climate variations to create and maintain a variety of wetland classes. These wetlands possess unique environmental and biotic characteristics that add...
Altitude of the top of the Minnekahta Limestone in the Black Hills area, South Dakota
Janet M. Carter, Jack A. Redden
1999, Hydrologic Atlas 744-B
This map is a product of the Black Hills Hydrology Study, which was initiated in 1990 to assess the quantity, quality, and distribution of surface water and groundwater in the Black Hills area of South Dakota (Driscoli, 1992). This long-term study is a cooperative effort between the U.S. Geological Survey...
Altitude of the top of the Deadwood Formation in the Black Hills area, South Dakota
Janet M. Carter, Jack A. Redden
1999, Hydrologic Atlas 744-E
This map is a product of the Black Hills Hydrology Study, which was initiated in 1990 to assess the quantity, quality, and distribution of surface water and ground water in the Black Hills area of South Dakota (Driscoll, 1992). This long-term study is a cooperative effort between the U.S. Geological...
Upper Klamath Lake Basin nutrient-loading study: Assessment of historic flows in the Williamson and Sprague rivers
John C. Risley, Antonius Laenen
1999, Water-Resources Investigations Report 98-4198
The Williamson River Basin, located in south-central Oregon, has a drainage area of approximately 3,000 square miles. The Sprague River, which flows into the Williamson River Basin, has a drainage area of 1,580 square miles. Together, the Williamson and Sprague Rivers supply about one-half of the inflow to Upper Klamath...
Hydrologic units
Water Resources Division, U.S. Geological Survey
1999, Report
Adsorption of bacteriophages on clay minerals
Sandip Chattopadhyay, Robert W. Puls
1999, Environmental Science & Technology (33) 3609-3614
The ability to predict the fate of microorganisms in soil is dependent on an understanding of the process of their sorption on soil and subsurface materials. Presently, we have focused on studying the thermodynamics of sorption of bacteriophages (T-2, MS-2, and φX-174) on clays (hectorite, saponite, kaolinite, and clay fraction...
Correlated factors in amphibian decline: Exotic species and habitat change in western Washington
M. J. Adams
1999, Journal of Wildlife Management (63) 1162-1171
Amphibian declines may frequently be associated with multiple, correlated factors. In western North America, exotic species and hydrological changes are often correlated and are considered 2 of the greatest threats to freshwater systems. Bullfrog (Rana catesbeiana) introductions are frequently cited as a threat to lentic-breeding anurans native to western North...
Regional hydrology of the Dixie Valley geothermal field, Nevada: preliminary interpretations of chemical and isotopic data
Gregory Nimz, Cathy Janik, Fraser Goff, Charles Dunlap, Mark Huebner, Dale Counce, Stuart D. Johnson
1999, Book chapter, Global geothermal resources: sustainable energy for the future
Chemical and isotopic analyses of Dixie Valley regional waters indicated several distinct groups ranging in recharge age from Pleistocene (1000a). Geothermal field fluids (~12-14 ka) appear derived from water similar in composition to non thermal groundwater observed today in valley artesian well (also ~14 ka). Geothermal fluid interaction with mafic...
Geochronologic and isotope studies of calcite and silica constraining Quaternary unsaturated- and saturated zone hydrologic flux at Yucca Mountain, Nevada, USA
James B. Paces, Zell E. Peterman, Leonid A. Neymark, Joseph F. Whelan, Brian D. Marshall
1999, Conference Paper, Use of hydrogeochemical information in testing groundwater flow models: Technical summary and proceedings of a workshop
Both unsaturated- and saturated-zone aqueous solutions are capable of precipitating secondary mineral deposits that document the history and origins of past water flux. Calcite and opal occur as thin coatings on open fractures and cavity floors within the thick unsaturated zone at Yucca Mountain. Outermost surfaces of calcite have 14C ages...
Field methods for measurement of fluvial sediment
Thomas K. Edwards, G. Douglas Glysson
1999, Techniques of Water-Resources Investigations 03-C2
This chapter describes equipment and procedures for collection and measurement of fluvial sediment. The complexity of the hydrologic and physical environments and man's ever-increasing data needs make it essential for those responsible for the collection of sediment data to be aware of basic concepts involved in processes of erosion, transport,...
Oxygen isotopes of dissolved sulfate as a tool to distinguish natural and mining-related dissolved constituents
Winfield G. Wright, D. Kirk Nordstrom
1999, Report
Natural and mining-related dissolved-constituent concentrations need to be distinguished in a watershed affected by abandoned mines to prioritize subbasins for remediation and to assist with the establishment of water-quality standards. The oxygen isotopes of dissolved sulfate can be used to distinguish between natural and mining-related sources of dissolved constituents. Several...
Water-quality variability in San Francisco Bay: general patterns of change during 1997
J. E. Cloern, B.E. Cole, J.L. Edmunds, J.I. Baylosis
1999, Report, 1997 annual report, San Francisco estuary regional monitoring program for trace substances
The 1997 Annual Report is the fifth Annual Report from the Regional Monitoring Program for Trace Substances (RMP) and contains a comprehensive description of RMP results from the 1997 monitoring year. As in previous years, the report includes results from the Base Program (water, sediment, and bivalve monitoring) and results...
Ground Water Atlas of the United States: Introduction and national summary
James A. Miller
1999, Hydrologic Atlas 730-A
The Ground Water Atlas of the United States provides a summary of the most important information available for each principal aquifer, or rock unit that will yield usable quantities of water to wells, throughout the 50 States, Puerto Rico, and the U.S. Virgin Islands. The Atlas is an outgrowth of...
Hydrologic data for the Columbia/Eagle Bluffs Wetland Complex, Columbia, Missouri-1993-96
Joseph M. Richards
1999, Open-File Report 99-607
The U.S. Geological Survey, in cooperation with the Missouri Department of Conservation and the city of Columbia, Missouri, collected hydrologic data from September 1993 through October 1996 as part of a hydrologic characterization of the Columbia/Eagle Bluffs Wetland Complex. The wetland complex was constructed in the Missouri River alluvial plain...
Distribution of major herbicides in ground water of the United States
Jack E. Barbash, Gail P. Thelin, Dana W. Kolpin, Robert J. Gilliom
1999, Water-Resources Investigations Report 98-4245
Information on the concentrations and spatial distributions of pesticides and their transformation products, or degradates, in the hydrologic system is essential for managing pesticide use in both agricultural and nonagricultural settings to protect water resources. This report examines the occurrence of selected herbicides and their degradates in ground water, primarily...
Selected hydrologic features of the Lake Tahoe Basin and surrounding area, California and Nevada, 1998
J. LaRue Smith, J.C. Stone, T.G. Rowe, J.V. Gardener
1999, Water-Resources Investigations Report 99-4031
Bioaccumulation of metals by the bivalve Macoma balthica at a site in South San Francisco Bay between 1977 and 1997: Long-term trends and associated biological effects with changing pollutant loadings
Michelle I. Hornberger, S. N. Luoma, D. Cain, F. Parchaso, C. Brown, R. Bouse, C.J. Wellise, John Thompson
1999, Open-File Report 99-55
No abstract available....
ERF1 -- Enhanced River Reach File 1.2
Richard B. Alexander, John W. Brakebill, Robert E. Brew, Richard A. Smith
1999, Open-File Report 99-457
U.S. Environmental Protection Agency's River Reach File 1 (RF1) to ensure the hydrologic integrity of the digital reach traces and to quantify the mean water time of travel in river reaches and reservoirs [see USEPA (1996) for a description of the original RF1]....
Synoptic survey of septic indicators in streams and springs at Monte Sano Mountain, Madison County, Alabama, January 29-31, 1998
Ann K. McPherson, Will S. Mooty
1999, Water-Resources Investigations Report 98-4230
The U.S. Geological Survey conducted a synoptic investigation of fecal bacterial pollution in headwater streams and springs on Monte Sano Mountain. A total of 18 sites were sampled over a 3 day period in late January 1998. Fifteen of the sites were located hydrologically downgradient from residential areas on top...
Hourly and daily variation of sediment redox potential in tidal wetland sediments
W. James Catallo, editor(s)
1999, Biological Science Report 1999-0001
Variation of electrochemical oxidation-reduction (redox) potential was examined in surface salt march sediments under conditions of flooding and tidal simulation in mesocosms and field sites. Time series were generated of redox potential measured in sediment profiles at 2-10 cm depth using combination Pt-Ag/AgCl (ORP) electrodes. Redox potential data were...
