bluuebunny/crossref_metadata_2025_split huggingface dataset:
Results of Seepage Meter and Mini‐Piezometer Study, Lake Mead, Nevada
Authors: Woessner William W. , Sullivan Kevin E. 
Published: March 2006

ABSTRACTThe seepage meter and the mini‐piezometer were utilized in an attempt to evaluate ground‐water reservoir interactions over a 12‐month period at Echo Bay in Lake Mead. In conjunction with these techniques three standard piezometers, refraction seismic data, and water chemistry data were utilized to interpret seepage device results. During a four‐month period, from December 1979 to March 1980, an 8 ft (2.5 m) rise in reservoir stage, the reservoir contributed water to Echo Wash bank storage at rates of up to 0.29 gpd/ft2 (12 lpd/m2). Ground‐water discharge occurred for the remainder of the project, during a stage decline from April 1980 to May 1980, a rise in June 1980, and leveling off and slight decline for the remainder of the year, July 1980 to December 1980. The maximum seepage meter ground‐water discharge rate of 3.0 gpd/ft2 (122 lpd/m2) was recorded in December 1980. Seepage meter water chemistry data for June were similar to Lake Mead water chemistry and were interpreted to be previously recharged Lake Mead water. September water chemistry data showed two possible components of ground‐water discharge, a high SpC calcium sulfate Echo Wash ground water and a lower SpC Lake Mead recharged bank storage water. December ground‐water chemistry data showed discharge to be a high SpC calcium sulfate water similar to Echo Wash ground‐water quality which was apparently unaffected by Lake Mead inflow. Mini‐piezometer data were collected at each seepage meter site. However, these data usually did not provide correlative results with seepage meter data probably because of suspended sediment in the piezometer water column and plugging of the perforated tip. Seepage meters were successfully utilized to characterize reservoir ground‐water interaction in Echo Bay.
Weighting of Observed Heads for the Inverse Problem
Authors: Ross Benjamin 
Published: March 2006

ABSTRACTIn using least‐squares parameter estimation techniques to solve for hydrogeologic parameters, one may use a weighting function to reflect differing reliabilities of head measurements. In studies published to date, the weighting function has been used in an ad boc manner or not at all. The inverse square of the observed hydraulic gradient, adjusted to reflect the modeler's perception of geologic heterogeneity and data reliability, is typically an appropriate weighting function.
Determination of the Hydrogeologic Properties of Lakebeds Using Offshore Geophysical Surveys
Authors: Bradbury Kenneth R. , Taylor Robert W. 
Published: March 2006

ABSTRACTStudies of the relationships between ground‐water systems and surface‐water systems (lakes) generally require knowledge of the hydrogeologic properties of lakebed materials. Direct measurement of these properties may be prohibitively expensive or difficult in an offshore environment. A correlation between longitudinal conductance, a geoelectric parameter, and lakebed leakance (vertical hydraulic conductivity divided by thickness) may provide a rapid and inexpensive method for estimating lakebed hydrogeological properties using data collected by offshore seismic and electrical surveys. A test of the method at three study sites in Lake Michigan shows a positive linear relationship between the logarithm of longitudinal conductance and the logarithm of lakebed leakance at the three sites.
Aquifer Classification for the UIC Program: Prototype Studies in New Mexico
Authors: Wilson Lee , Holland Michael T. 
Published: March 2006

ABSTRACTThree case studies from New Mexico illustrate methods by which aquifers can be classified for purposes of the Federal Underground Injection Control program. The principal technique involves preparation of hydrogeologic maps or cross sections which display information on the permeability of rock units and the dissolved solids content of formation fluids. Because deep water wells are lacking in most areas, the analysis normally requires considerable interpretation of geological and geophysical logs collected by energy and mineral companies, plus use of a general model or concept about regional hydrogeology. Injection of waste fluids into aquifers containing water with less than 10,000 mg/1 dissolved solids is not allowed unless an exemption is justified by economic, engineering and other factors. Based on the case studies, regulatory exemptions will be possible for aquifers which are hydrocarbon or mineral‐producing, or which are important for brine disposal purposes.
Role of Geological and Geophysical Data in Modeling a Southwestern Alluvial Basin
Authors: O'Brien Keith M. , Stone William J. 
Published: March 2006

ABSTRACTA parameter‐estimation technique based on existing hydrological, geophysical, and geological data was developed to approximate transmissivity values for use in a ground‐water flow model of the Animas Valley, southwest New Mexico. Complete Bouguer gravity anomaly maps together with seismic‐refraction profiles, geologic maps, geologic, geophysical, and drillers' logs, water levels, and pumping‐test data provide insight into the transmissivity of bolson deposits throughout the basin.The transmissivity distribution was primarily based on reported pumping and specific‐capacity tests in conjunction with complete Bouguer gravity anomaly maps and well log data. Reported transmissivity values were characterized by gravity values and well log data. In grid blocks lacking pumping and specific‐capacity tests, transmissivity values were assigned based on the relationship of gravity values and well log data within the grid block to gravity values and well log data within other grid blocks for which transmissivity values are available.A two‐dimensional, finite‐difference, ground‐water flow computer code was used to evaluate the effectiveness of the parameter‐estimation technique. Although the trial‐and‐error method of calibration was employed, the actual computer time necessary for model calibration was minimal. The conceptually straightforward approach for parameter estimation utilizing existing hydrological, geophysical, and geological data provides realistic parameter estimates.
Thermal Impact of Residential Ground‐Water Heat Pumps
Authors: Warner Don L. , Algan Ugur 
Published: March 2006

ABSTRACTA computer simulation study was conducted to quantify the potential thermal impact of residential water‐source heat pump usage on ground‐water aquifers.In a first phase of the study, weather data for nine locations throughout the country were used to estimate the energy requirements for heating and air conditioning a typical residence. These energy requirements were then translated into the volumetric water demands for a selected heat pump at each location. A representative model aquifer was then defined and its characteristics used, along with the heat pump water requirements and design ΔT's (difference between inlet and outlet water temperature) to identify the important parameters that contribute to heat transfer and to model the movement of the thermal front resulting from injection of heat pump discharge water at the nine locations.The major factor that determines the heat pump thermal impact was found to be the net amount of heat injected into, or removed from an aquifer. Other significant factors included well design, heat pump design ΔT, and physical properties of the aquifer such as thickness, porosity and dispersivity.The study showed that, in climates where winter heating demand is very nearly equal to summer cooling demands, the injection of heat pump discharge water did not cause any significant modification of the ambient model aquifer temperature. However, in hot or cold climates where air conditioning or heating demand dominates, measurable thermal changes occurred in the model aquifer. In most cases, the maximum temperature
The Investigation of Aquifer Parameters Using Multiple Piezometers
Authors: Walthall S. , Lngram J. A. 
Published: March 2006

ABSTRACTIn order to investigate the aquifer parameters of a fissured layered sandstone aquifer, it was found necessary to construct and test an abstraction borehole using laboratory, double packer, geophysical and pumping test techniques. Good correlation was found between the techniques when the aquifer was represented by a fissured layered aquifer with low permeability bands separating layers of higher permeability. The use of multiple piezometers proved to be the only way of obtaining sensible results for field pumping tests and has given storage coefficients for both the confined and unconfined sections of the aquifer.
Impact of Land Use on Ground‐Water Quality in Southern Delawarea
Authors: Ritter William F. , Chirnside Anastasia E. M. 
Published: March 2006

ABSTRACTA ground‐water quality monitoring study was conducted in Kent and Sussex Counties, Delaware. In the coastal region of Sussex County, 210 wells were sampled 12 times each. In noncoastal Sussex and Kent Counties, 272 wells were sampled once each season over a period of one year. Over 99 percent of the wells were in the water‐table aquifer.In coastal Sussex County, 32% of the wells had average nitrate concentrations above the EPA drinking‐water standard of 10 mg/1 N. In noncoastal Sussex County and Kent County, 21% and 8% of the wells respectively, had nitrate concentrations above 10 mg/1. The highest nitrate concentrations occurred in areas with intensive broiler production or intensive crop production with excessively‐drained soils. Nitrate concentrations in forest areas were <1.5 mg/1. Poultry manure, septic tanks and fertilizers all contributed to the high nitrate concentrations. Poultry manure was one of the major causes of nitrate contamination in four out of the five top prioritized ground‐water problem areas.Bacteria contamination was low in all sampling areas. Lead, cadmium and chromium were far below drinking‐water standards in all but a few wells.
Remote Sensing and Geophysical Investigations of Glacial Buried Valleys in Northeastern Kansas
Authors: Denne Jane E. , Yarger Harold L. , Macfarlane P. Allen , Knapp Ralph W. , Sophocleous Marios A. , Lucas James R. , Steeples Don W. 
Published: March 2006

ABSTRACTAquifers found in glacial buried valleys are a major source of good‐quality ground water in northeastern Kansas. The extent and character of many of these deposits are not precisely known, so a detailed study of the buried valleys was undertaken. Test drilling, Landsat imagery, shallow‐earth temperature measurements, seismic refraction, surface electrical resistivity, and gravity data were used to evaluate two sites in Nemaha and Jefferson Counties. Tonal patterns on springtime Landsat imagery and winter/summer anomalies in shallow‐earth temperatures were quick and inexpensive methods for locating some glacial buried aquifers and suggested areas for more intensive field studies. Reversed seismic refraction and resistivity surveys were generally reliable indicators of the presence or absence of glacial buried valleys, with most depth determinations being within 25% of test‐drilling results. The effectiveness of expensive test‐hole drilling was greatly increased by integrating remote sensing, shallow‐earth temperature, seismic, and resistivity techniques in the two buried valley test areas. A gravity profile allowed precise definition of the extent of one of the channels after the other techniques had been used for general information.
Ground‐Water Mounding Beneath a Large Leaching Bed
Authors: Chan H. T. , Sykes J. F. 
Published: March 2006

ABSTRACTAn 84 m (276 ft) by 64 m (205 ft) experimental leaching bed was constructed to receive the secondary effluent from the Norwood, Ontario sewage treatment plant. The distribution system consisted of 100 mm diameter perforated pipes laid 2.1 m apart in 0.45 m wide trenches. The main soil layer at the test site was sandy silt. Ground‐water levels at the site were measured approximately weekly at 36 piezometers for a period of about 2½ years. An initial hydraulic loading of 122,700 1/day caused surface ponding. A reduced loading of 40,900 1/day was then used for most of the study period. Ground‐water level fluctuations beneath and adjacent to the leaching bed were attributed to seasonally varying infiltration and hydraulic loading. The experimental data were simulated using a transient two‐dimensional, phreatic integrated depth finite‐element model and an analytic solution for ground‐water mounding. Results from the study indicated that seasonal infiltration was a controlling factor in determining leaching bed design loads. Both mathematical models were found adequate for design.
The Hydrological Effects of Gravel Winning in an Area West of London, United Kingdom
Authors: Morgan‐Jones M. , Bennett S. , Kinsella J. V. 
Published: March 2006

ABSTRACTThe ground‐water flow and ground‐water quality of extensive gravel deposits in the Lower Colne Valley, near London, England are described. The great demand for aggregates in southeast England over the past 30 years has resulted in extensive exploitation of these gravels, the worked‐out pits being either left water‐filled for recreational purposes, or filled with a variety of waste materials. Both after‐uses are shown to alter the ground‐water situation either by locally lowering or raising ground‐water levels, such effects having been described in both French and German literature, or by causing ground‐water and surface‐water pollution problems. If the scale of pit development or landfilling is large as in the Lower Colne Valley, then remedial measures have to be undertaken to minimize the pollution risk and to obviate problems caused by raised or lowered ground‐water levels.
Analysis of Conceptual Designs for Remedial Measures at Lipari Landfill, New Jersey
Authors: Andersen Peter F. , Faust Charles R. , Mercer James W. 
Published: March 2006

ABSTRACTDuring the two‐week period from March 12 through March 26, 1982, a preliminary conceptual design analysis on various remedial measures for the Lipari Landfill, New Jersey, was performed. This site is currently ranked at the top of the EPA's Superfund Cleanup List. This report demonstrates the practical benefits and limitations of applying models (both analytical and numerical) to a hazardous waste site in a restricted period of time. The numerical model was used to simulate current flow conditions at the site and provide initial conditions for a series of sensitivity simulations. These sensitivity simulations were designed to test (1) a slurry wall, (2) drain location, (3) drain depth, and (4) a clay cap. Analytical solutions were designed to analyze (1) water in place, (2) flow through an underlying layer, the lower Cohansey, (3) draining the lower Cohansey, (4) flushing the contaminated area using wells, and (5) convective arrival time of contaminants to drains. This analysis quantified discharge to drains, flow rates to a swamp downstream of the landfill, time required to drain the landfill, and contaminant travel times that would result from the implementation of each of the remedial measures that were suggested. The conclusions from this study were used by engineers and planners who incorporated, economics and engineering decisions for the various remedial measures considered.
Algorithm for Theis Solution
Authors: Gupta A. Das , Joshi S. G. 
Published: March 2006

ABSTRACTAn algorithm for the Theis solution of pumping test data has been developed taking into account the basic principles of graphical approach of curve‐matching. The method is simple and does not need initial approximation of transmissivity and storativity as required by approaches suggested by Saleem (1970) and McElwee (1980). As a measure of error of fitting, integral square error is computed between the observed drawdown and drawdown calculated from the theoretical equation with the values of coefficients estimated by the procedure. Also root mean square deviation in drawdown is calculated. The algorithm is capable of identifying data with errors in observation or recording. The reliability of the algorithm and its limitations are discussed on the basis of test runs with synthetic data having varying magnitudes of error and varying distributions of error points in the data set. The estimates of parameters by the proposed algorithm for a typical field test data compare very well with the estimates by the sensitivity approach developed by McElwee (1980).
Contamination of Aquifers by Overpressuring the Annulus of Oil and Gas Wells
Authors: Harrison Samuel S. 
Published: March 2006

ABSTRACTMedina gas wells and oil wells in northwestern Pennsylvania, northeastern Ohio, and western New York create a potential for contamination of the fresh‐water aquifers that overlie the production zones of these wells. Most of these wells are constructed in a manner which results in an open annulus which is a few hundred to a few thousand feet long below the surface casing of the well. This annulus is a potential avenue of migration of contaminants from strata of higher hydrodynamic pressure into formations of lower hydrodynamic pressure. If gas from the strata exposed to the annulus is not permitted to escape to the atmosphere, the annulus may become pressurized, and a hydraulic gradient may be created between the potential contaminants in the annulus (e.g., brine and/or natural gas) and the overlying fresh‐water aquifers. If a permeability pathway exists between the pressurized annulus and an overlying fresh‐water aquifer, contamination of the aquifer will result.The risk of contaminating fresh ground water with the contents of a gas‐ or oil‐well annulus could be greatly reduced by filling the annulus with cement. An alternative precaution would be to operate the well in a manner that does not allow the annulus pressure to exceed the normal pressure of the formations exposed to the annulus.
Performance and Analysis of Drillstem Tests in Small‐Diameter Boreholes
Authors: Marinelli Fred , Rowe Jerry W. 
Published: March 2006

ABSTRACTWhile drillstem tests have been used extensively in the petroleum industry to obtain reliable measurements of hydraulic parameters in single boreholes, the technique has been used only to a limited extent in ground‐water investigations. This is due in part to the limited availability and high cost of suitable equipment for small‐diameter boreholes. In this study, drillstem tests were performed in exploratory boreholes to evaluate the hydraulic characteristics of a proposed compressed air energy storage site in central Illinois. The tests were conducted in small‐diameter coreholes (vertical and inclined) at depths up to 610 meters (2000 ft) using a drillstem tool designed and field‐tested by the authors. Field data were analyzed using semilog and curve‐matching techniques. Values of hydraulic conductivity obtained by the two methods were generally in very good agreement. The curve‐matching method allowed for calculation of wellbore storage and an estimation of well‐bore damage (skin effect). Test results indicate that exploratory boreholes were severely damaged by the coring process. In the presence of wellbore damage, slug test hydraulic conductivities were significantly lower than those given by drillstem tests conducted in the same zones. The sole use of slug tests would have underestimated hydraulic conductivity and led to erroneous conclusions regarding site conditions. The drillstem test methodology described herein offers a cost‐effective technique for measuring representative values of hydraulic conductivity in single boreholes.
Characterization of Dye Tracer Plumes: In Situ Field Experiments
Authors: Naymik Thomas G. , Sievers Mark E. 
Published: March 2006

ABSTRACTThe second ground‐water dye tracer experiment at Sand Ridge State Forest, Illinois, was conducted during the Spring of 1983. Slugs of three different fluorescent dyes (Rhodamine WT, Amino G Acid, and Lissamine FF) were allowed to migrate under natural hydraulic gradient conditions through a water‐table aquifer composed of wind‐blown sand overlaying glacial outwash sand and gravel. The plumes in the outwash deposit and in the dune sand were monitored first by a line of sand point wells placed perpendicular to flow at a distance of 10 ft and 5 ft, respectively, from the source wells. A trilevel nest of sand points was then placed in the path of each plume at a greater distance (50 feet from the sources of the deep plumes). The field data suggest that the plume geometry varied with distance from the source. A solute transport model, calibrated to the field data, provided estimates of longitudinal dispersivity (0.10 ft and 0.17 ft for the plumes in the lower unit) and average linear velocity (approximately 1.5 and 1.7 ft/day in the lower unit and 0.21 ft/day in the upper unit). The model was then used as a mass accounting system to relate the tracer concentrations detected in monitoring wells to the mass within the plumes.
Waste‐Water Injection: Geochemical and Biogeochemical Clogging Processes
Authors: Oberdorfer June A. , Peterson Frank L. 
Published: March 2006

ABSTRACTExamination of near‐well clogging processes at two experimental injection sites in Hawaii shows that filtration of suspended solids is not a long‐term cause of clogging. While particulate filtration is probably a short‐term cause of clogging at the start‐up of injection, the injected organics are biodegraded once the microbial biomass becomes established. The injection head gradient determined from monitoring wells shows that most of the initial head loss is immediately adjacent to the well, but that after several weeks it shifts to a region over 0.5 m from the well. Denitrifying bacteria become sufficiently numerous to produce significant amounts of nitrogen gas, which in turn produces a gas‐bound zone about 0.5 to 1 m from the well. With continued injection the nitrogen gas‐bound zone is slowly extended farther out into the injection stratum. Dissolution of the carbonate aquifer also occurs, but its effects are partially masked by gas binding.
Estimating Aquifer Permeability from Formation Resistivity Factors
Authors: Kwader Thomas 
Published: March 2006

ABSTRACTA comparison of permeability results for individual producing zones obtained from pumping tests and flow‐meter logs showed a good correlation to calculated corresponding formation resistivity factors (F). Where F = a/Øm or F = R0/RW, and porosity (Ø) is obtained from the neutron log, m is the formation cementation factor, Ro is saturated formation resistivity from normal electric logs, and Rw is formation pore‐water resistivity. Unlike formations containing saline water where the electrical current is conducted through the pore fluid, in fresh‐water aquifers the electrical current appears to be conducted along the grain‐aqueous interface by surface conductance rather than through the grain or pore fluid. Surface conductance of the current serves to increase the current path length which is recorded as an increase in the measured saturated resistivity (Ro). The current path direction and length through the formation is directly related to the shape, diameter, and sorting of the grains, geometric packing arrangement, and degree of matrix cementation. Fortunately, all of these factors that serve to increase the current path [which in turn directly increase saturated formation resistivity (Ro) and F] also are factors that increase formation permeability.Relative changes in F values can be matched with known permeabilities from aquifer tests and flowmeter logs to quantify the relative productivity of the various zones analyzed. Once this relationship is established, F values can be used to assign relative permeabilities within a single borehole or from borehole to borehole for a given geographical area.This method has been successfully used to estimate permeability in both unconsolidated sands and Tertiary carbonate aquifers in the southeastern Coastal Plain of the United States.