Chloride interference in the analysis of dissolved organic carbon by the wet oxidation method
George R. Aiken
1992, Environmental Science & Technology (26) 2435-2439
The presence of Cl- in concentrations greater than 0.02 M is shown to interfere with the analysis of aqueous DOC concentrations by the wet oxidation method of analysis when a reaction time of 5 min is employed. Chloride competes with DOC for S2O82-, lowering the overall oxidation efficiency. The resulting...
Consumption of freons CFC-11 and CFC-12 by anaerobic sediments and soils
Derek R. Lovley, J.C. Woodward
1992, Environmental Science & Technology (26) 925-929
A variety of anaerobic sediments and soils consumed CFC-11 (CFCl3) and CFC-12 (CF2Cl2). An aerobic soil did not. Active microbial metabolism was required for CFC-12 uptake in all of the sediments examined. CFC-11 uptake was faster in the presence of microbial activity, but reduced components in the sediments also resulted...
Groundwater flow, velocity, and age in a thick, fine-grained till unit in southeastern Wisconsin
W.W. Simpkins, K. R. Bradbury
1992, Journal of Hydrology (132) 283-319
Piezometer nests were installed at study sites in each of five north-south-trending end moraines of the late Pleistocene Oak Creek Formation in southeastern Wisconsin. The formation is composed primarily of a fine-grained glacial diamicton (till) and laterally continuous and discontinuous, coarse-grained lake and meltwater stream sediment. It overlies the Silurian...
Use of a regional atmospheric model to simulate lake-atmosphere feedbacks associated with Pleistocene Lakes Lahontan and Bonneville
S. W. Hostetler, F. Giorgi
1992, Climate Dynamics (7) 39-44
A regional model of the atmosphere (version 4 of the NCAR mesoscale model, MM4) was used to assess whether lake-effect precipitation was a significant component of the late-Pleistocene hydrologic budgets of Lakes Lahontan and Bonneville. Control simulations for January and July of 1979 were made using MM4, and the Pleistocene...
Residence times in river basins as determined by analysis of long-term tritium records
R. L. Michel
1992, Journal of Hydrology (130) 367-378
The US Geological Survey has maintained a network of stations to collect samples for the measurement of tritium concentrations in precipitation and streamflow since the early 1960s. Tritium data from outflow waters of river basins draining 4500–75000 km2 are used to determine average residence times of water within the basins. The...
Pesticide residues in ground water of the San Joaquin Valley, California
Joseph L. Domagalski, N. M. Dubrovsky
1992, Journal of Hydrology (130) 299-338
A regional assessment of non-point-source contamination of pesticide residues in ground water was made of the San Joaquin Valley, an intensively farmed and irrigated structural trough in central California. About 10% of the total pesticide use in the USA is in the San Joaquin Valley. Pesticides detected include atrazine,...
Classifying and mapping wetlands and peat resources using digital cartography
Cornelia C. Cameron, David A. Emery
1992, Conference Paper, ASTM Special Technical Publication
Digital cartography allows the portrayal of spatial associations among diverse data types and is ideally suited for land use and resource analysis. We have developed methodology that uses digital cartography for the classification of wetlands and their associated peat resources and applied it to a 1:24 000 scale map area...
Solution of the advection-dispersion equation by a finite-volume eulerian-lagrangian local adjoint method
R. W. Healy, T.F. Russell
1992, Conference Paper, Finite Elements in Water Resources, Proceedings of the International Conference
A finite-volume Eulerian-Lagrangian local adjoint method for solution of the advection-dispersion equation is developed and discussed. The method is mass conservative and can solve advection-dominated ground-water solute-transport problems accurately and efficiently. An integrated finite-difference approach is used in the method. A key component of the method is that the integral...
Semiempirical model of soil water hysteresis
J. R. Nimmo
1992, Soil Science Society of America Journal (56) 1723-1730
In order to represent hysteretic soil water retention curves accurately using as few measurements as possible, a new semiempirical model has been developed. It has two postulates related to physical characteristics of the medium, and two parameters, each with a definite physical interpretation, whose values are determined empirically for a...
Atrazine mineralization potential of alluvial-aquifer sediments under aerobic conditions
P.B. McMahon, F. H. Chapelle, M.L. Jagucki
1992, Environmental Science & Technology (26) 1556-1559
No abstract available....
Comparison of purge and trap GC/MS and purgeable organic chloride analysis for monitoring volatile chlorinated hydrocarbons
Larry B. Barber, E. Michael Thurman, Yoshi Takahashi, Mary C. Noriega
1992, Ground Water (30) 836-842
A combined field and laboratory study was conducted to compare purge and trap gas chromatography/mass spectrometry (PT‐GC/MS) and purgeable organic chloride (POC1) analysis for measuring volatile chlorinated hydro‐carbons (VCH) in ground water. Distilled‐water spike and recovery experiments using 10 VCH indicate that at concentrations greater than...
Humic substances and trace metals associated with Fe and Al oxides deposited in an acidic mountain stream
Diane M. McKnight, R.L. Wershaw, K.E. Bencala, G. W. Zellweger, G. L. Feder
1992, Science of Total Environment (117-118) 485-498
Hydrous iron and aluminum oxides are deposited on the streambed in the confluence of the Snake River and Deer Creek, two streams in the Colorado Rocky Mountains. The Snake River is acidic and has high concentrations of dissolved Fe and Al. These metals precipitate at the confluence with the pristine,...
Patterns and rates of ground-water flow on Long Island, New York
Herbert T. Buxton, Edward Modica
1992, Groundwater (30) 857-866
Increased ground-water contamination from human activities on Long Island has prompted studies to define the pattern and rate of ground-water movement. A two-dimensional, fine-mesh, finite-element model consisting of 11,969 nodes and 22,880 elements was constructed to represent ground-water flow along a north-south section through central Long Island. The model represents...
Herbicide transport in rivers: Importance of hydrology and geochemistry in nonpoint-source contamination
P. J. Squillace, E.M. Thurman
1992, Environmental Science & Technology (26) 538-545
Alachlor, atrazine, cyanazine, metolachlor, and metribuzin were measured at six sites during 1984 and 1985 in large subbasins within the Cedar River, IA. A computer model separated the Cedar River discharge hydrograph into groundwater and overland-flow components. The concentration of herbicides in the river when groundwater was the...
Floodplain storage of mine tailings in the Belle Fourche river system: a sediment budget approach
D. C. Marron
1992, Earth Surface Processes and Landforms (17) 675-685
Arsenic‐contaminated mine tailings that were discharged into Whitewood Creek at Lead, South Dakota, from 1876 to 1978, were deposited along the floodplains of Whitewood Creek and the Belle Fourche River. The resulting arsenic‐contaminated floodplain deposit consists mostly of overbank sediments and filled abandoned meanders along White‐wood Creek, and overbank and...
Importance of methane-oxidizing bacteria in the methane budget as revealed by the use of a specific inhibitor
Ronald S. Oremland, Charles W. Culbertson
1992, Nature (356) 421-423
METHANE is a greenhouse gas whose concentration in the atmosphere is increasing. Much of this methane is derived from the metabolism of methane-generating (methanogenic) bacteria and over the past two decades much has been learned about the ecology of methanogens; specific inhibitors of methanogenesis, such as 2-bromoethanesulphonic acid, have proved useful...
Gravel-bed deposition and erosion by bedform migration observed ultrasonically during storm flow, North Fork Toutle River, Washington
R.L. Dinehart
1992, Journal of Hydrology (136) 51-71
Ultrasonic depth sounding provides useful and unexpected information about peak discharge and sediment transport when applied during storm flow in channels with erodible beds. Streambed elevation was measured with dual ultrasonic depth sounders during the rise, crest, and recession of a storm flow in the North Fork Toutle River,...
Use of geochemical biomarkers in bottom sediment to track oil from a spill, San Francisco Bay, California
F. D. Hostettler, J. B. Rapp, K.A. Kvenvolden
1992, Marine Pollution Bulletin (24) 15-20
In April 1988, approximately 1500 m3 of a San Joaquin Valley crude oil were accidentally released from a Shell Oil Co. refinery near Martinez, Californa. The oil flowed into Carquinez Strait and Suisun Bay in northern San Francisco Bay Sediment and oil samples were collected within a week and analysed...
Comparison of methods for the removal of organic carbon and extraction of chromium, iron and manganese from an estuarine sediment standard and sediment from the Calcasieu River estuary, Louisiana, U.S.A.
N.S. Simon, S.A. Hatcher, C. Demas
1992, Chemical Geology (100) 175-189
U.S. National Bureau of Standards (NBS) estuarine sediment 1646 from the Chesapeake Bay, Maryland, and surface sediment collected at two sites in the Calcasieu River estuary, Louisiana, were used to evaluate the dilute hydrochloric acid extraction of Cr, Fe and Mn from air-dried and freeze-dried samples that had been treated...
A spatial model to aggregate point-source and nonpoint-source water-quality data for large areas
D.A. White, R. A. Smith, C. V. Price, R. B. Alexander, K. W. Robinson
1992, Computers & Geosciences (18) 1055-1073
More objective and consistent methods are needed to assess water quality for large areas. A spatial model, one that capitalizes on the topologic relationships among spatial entities, to aggregate pollution sources from upstream drainage areas is described that can be implemented on land surfaces having heterogeneous water-pollution effects. An infrastructure...
Discussion of "Aeration at Ohio River basin navigation dams"
John S. Gulliver, Steven C. Wilhelms
1992, Journal of Environmental Engineering (118) 446-447
No abstract available....
Hydrology of Heber and Round Valleys, Wasatch County, Utah, with emphasis on simulation of ground-water flow in Heber Valley
D. Michael Roark, Walter F. Holmes, Heidi K. Shlosar
1991, Technical Publication 101
An investigation of the hydrologic system in Heber and Round Valleys was conducted to improve understanding of the surface-water and ground-water hydrology and the effects caused by changes in recharge. Ground water is present in consolidated rocks and in unconsolidated valley-fill deposits, but the principal ground-water reservoir is in the...
Hydrologic reconnaissance of the Sevier Lake area, west-central Utah
Dale E. Wilberg
1991, Technical Publication 96
The hydrologic system of the Sevier Lake area, at the terminus of the Sevier Lake drainage basin in west-central Utah, was studied during 1987-88 to determine baseline hydrologic conditions prior to anticipated development. Sevier Lake was reestablished during 1983-87 on the normally dry playa as a result of record volumes...
Hydrologic monitoring for effects of geothermal and ground-water development, Long Valley caldera, California
C. D. Farrar, D. L. Lyster
1991, Conference Paper, Symposium on Subsurface Injection of Geothermal Fluids, Santa Rosa, California
Groundwater flow and solute movement to drain laterals, western San Joaquin Valley, California: 2. Quantitative hydrologic assessment
John L. Fio, S. J. Deverel
1991, Water Resources Research (27) 2247-2257
Groundwater flow modeling was used to quantitatively assess the hydrologic processes affecting ground water and solute movement to drain laterals. Modeling results were used to calculate the depth distribution of groundwater flowing into drain laterals at 1.8 m (drain lateral 1) and 2.7 m (drain lateral 2) below land surface....
