Search Results

No abstract available....

Saturation indices computed with WATEQ4F chemical analyses from a groundwater in crystalline bedrock and a surface water receiving acid mine drainage are frequently at or above saturation with respect to calcite, fluorite, barite, gibbsite and ferrihydrite. Deep granitic groundwaters from Stripa, Sweden, are supersaturated with respect to calcite and fluorite....

Increased solubility of quartz and mobilization in contaminated groundwater due to the complexation with dissolved organic acids has been recently proposed [Bennett and Siegel, Nature326, 684–686 (1987)]. Using laser Raman and Fourier transform infrared spectroscopies, we have examined mixed solutions of oxalic and silicic acids at near neutral pH in...

No abstract available....

Because of the common occurrence of 15 to 25 mole percent hydronium substitution on the alkali site in jarosites, it is necessary to consider the hydronium content of jarosites in any attempt at rigorous evaluation of jarosite solubility or of the saturation state of natural waters with respect to jarosite....

Characteristics of an obligately methylotrophic coccoid methanogen (strain GS-16) previously isolated from estuarine sediment are described. Growth was demonstrated on dimethyl sulfide (DMS) or trimethylamine (TMA), but not on methane thiol, methane thiol plus hydrogen, dimethyl disulfide, or methionine. DMS-grown cells were able to metabolize DMS...

No abstract available....

Hydrologic data for Chester County, Pennsylvania are given for 3,010 wells and 32 springs. Water levels are given for 48 observation wells measured monthly during 1936-86. Chemical analyses of ground water are given for major ions, physical properties, nutrients, metals and other trace constituents, volatile organic compounds, acid organic compounds,...

Since 1979 the Geothermal Research Program of the U.S. Geological Survey has carried out multidisciplinary research in the Cascade Range. The goal of this research is to understand the geology, tectonics, and hydrology of the Cascades in order to characterize and quantify geothermal resource potential. A major goal of the...

No abstract available....

No abstract available....

No abstract available....

A Laplace transform solution was obtained for the injection of a tracer in a well situated in a homogeneous aquifer where steady, horizontal, radially convergent flow has been established due to pumping at a second well. The standard advection-dispersion equation for mass transfer was used as the controlling equation. For...

Geographic information systems allow for the interactive analysis of spatial data related to water-resources investigations. A conceptual design for an interface between a geographic information system and a watershed model includes functions for the estimation of model parameter values. Design criteria include ease of use, minimal equipment requirements, a generic...

Digital elevation models (DEMs) are being used to determine variable inputs for hydrologic models in the Delaware River basin. Recently developed software for analysis of DEMs has been applied to watershed and streamline delineation. The results compare favorably with similar delineations taken from topographic maps. Additionally, output from this software...

This abstract refers to technical recommendations for avoiding, minimizing, and restoring (i.e., mitigating) drilling site access impacts related to oil and gas activities in coastal wetlands through regulatory review, drawing mostly from the Louisiana experience. The two standard methods used to access wetland drilling locations are canals and roads, both...

On January 15, 1889, the U.S. Geological Survey began collecting sediment data on the Rio Grande at Embudo, New Mexico. During the past 100 years the U.S. Geological Survey's Water Resources Division (WRD) has collected daily sediment data at more than 1,200 sites. Projects have addressed the problems associated with...

Water extracted from fluid inclusions in quartz from shallow epithermal ore deposits often has a hydrogen isotope composition (δD) different from that of water extracted from inclusions in associated minerals. This difference is usually attributed to the involvement of primary fluids from multiple sources. Isotopic and homogenization and freezing temperature...

The role of cation exchange in the retardation of ammonium (NH4+) and potassium (K+) transport in a shallow sand and gravel aquifer was evaluated by use of observed distributions of NH4+ and K+ within a plume of sewage-contaminated groundwater, small-scale tracer injection tests, and batch sorption experiments on aquifer material....

This paper examines forecasts of changes in watershed runoff in the Delaware River basin that result from a range of predicted effects of increased atmospheric carbon dioxide (CO2) on future precipitation, temperature, and stomatal resistance of plants. A deterministic hydrologic model, TOPMODEL, was driven with stochastic inputs of temperature and...

Water solubility enhancements of 1,1-bis(p-chlorophenyl)-2,2,2-trichloroethane (DDT) and 1,2,3-trichlorobenzene (TCB) by aqueous surfactants below and above their critical micelle concentrations (CMCs) have been studied at room temperature with the following surfactants: Triton X-100, Triton X-114, Triton X-405, Brij 35, sodium dodecyl sulfate, and cetyltrimethylammonium bromide. While the solubilities of DDT and...

In various sediments in which Fe(III) reduction was the terminal electron-accepting process, [14C]glucose was fermented to 14C-fatty acids in a manner similar to that observed in methanogenic sediments. These results are consistent with the hypothesis that, in Fe(III)-reducing sediments, fermentable substrates are oxidized to carbon dioxide by the combined activity of...

A field study approach is proposed for reliably estimating hydraulic gradients in subregions within a region of variable-salinity ground water. It is based upon Hubbert's concept about the kind of density distributions that are required for ground water to have a potential. The approach consists of dividing a region of...

Multiple linear regression models calculated from readily obtainable chemical and physical parameters can explain a high percentage (70 per cent or greater) of observed sediment-trace element variance for Cu, Zn, Pb, Cr, Ni, Co, As, Sb, Se, and Hg in a widely divergent suite of...

Measurements on fluid inclusions in hydrothermal dolomite cements place constraints on sulfide precipitation mechanisms and on the thermal-hydrologic processes which formed the Viburnum Trend Mississippi Valley-type lead district. Homogenization temperatures and freezing point depressions were determined for fluid inclusions in Bonneterre Dolomite-hosted dolomite cements in mine samples, as well as...