bluuebunny/crossref_metadata_2025_split huggingface dataset:
An Evaluation of Sources of Nitrogen as Causes of Ground‐Water Contamination in Nassau County, Long Island
Authors: Porter Keith S. 
Published: July 2006

ABSTRACTAn evaluation of sources of nitrogen in an urban area indicates that it may be difficult to distinguish effects on the quality of underlying ground water. In Nassau County two principal sources of nitrogen are human waste water and fertilized turf. The effects of these sources, combined with other sources such as domestic animals and precipitation, are such that management of one source, i.e. the removal of waste water via sewers, may be less effective than expected.
BASIN MANAGEMENT IN THE SAN BERNARDINO BASIN AREA
Authors: Rowe Larry W. 
Published: July 2006

AbstractThe San Bernardino Valley Municipal Water District was formed in 1954 to master plan the long‐term water supply, including the importation of supplemental water, for that portion of the Upper Santa Ana River Basin area within the District.Prior to the development of a basin management program, the District first undertook to inventory the water resources available to it. Specifically, what is its quantity, distribution, quality, what stresses will the water supply be subjected to, and finally, how is it disposed of? To assemble and store this array of hydrologic data, the District, as part of its basin management program, has undertaken the creation of a hydrologic data base. To facilitate the storage and retrieval of all pertinent data, the District utilizes an on‐site high speed digital computer. Into this data base, the District has loaded all available information pertaining to ground‐water production, streamflows and diversions, rainfall, ground‐water levels, basin recharge, basin inflow/outflow, water quality, and consumptive use. Development and selection of alternative strategies is made more effective because of the availability of historic and real time hydrologic data. An additional benefit derived from the basin management program is that the updating of the operational economics associated with the importation of State Project water can be made with the benefit of the most current data available. This allows the District to optimize its programs and thus maximize the limited resources available to it.
Brine Pollution at Fresno — Twenty‐Six Years Later
Authors: Schmidt K. D. , Krancher J. A. , Bisel G. 
Published: July 2006

ABSTRACTChloride pollution of ground water was discovered in 1953 downgradient of seepage pits and wells used for disposal of waste waters. An ice plant and water softening plant at the Fresno railroad yard were the sources of pollution. A plume of polluted ground water was delineated, and the discharge from the major source (the water softening plant) was stopped in 1953. Sampling in the late 1970's indicated that high chloride contents were still present in ground water downgradient of the railroad yard. The plume expanded both vertically and horizontally in the aquifer, from a volume of about 1,500 acre‐feet (1.85 million cubic meters) in 1953 to 15,000 acre‐feet (18.5 million cubic meters) in 1979. Trilinear diagram plots of waste waters and ground water indicate that waste water from the ice plant continued to produce an impact into the 1970's. Recharge from canal seepage has created an important boundary, particularly on the west side of the plume. The rate of ground‐water flow, calculated on the basis of the advance of the chloride front, was about 200 feet (61 meters) per year, in close agreement with estimates based on water‐level slope and aquifer parameters.
An Economical Approach to Determining the Extent of Ground‐Water Contamination and Formulating a Contaminant Removal Plan
Authors: Mido Kiyoshi W. 
Published: July 2006

ABSTRACTIf past ground‐water movement in the vicinity of contamination could be shown pictorially, determination of the extent of contamination would be facilitated significantly. Furthermore, if pictorial representation of future ground‐water movement under presumed conditions reflecting alternative plans of contaminant removal or containment could be provided rapidly, an effective plan could be developed speedily and thus economically. A flow path and arrival time plot, which is developed through the use of a flow system kinematics mathematical model, provides such visualization of ground‐water movement. Contrary to the popular notion that the kinematics model requires much more geohydrologic datathan the finite difference or element models, it was found that meaningful kinematics models could be developed based on relatively limited data. Presented in this paper are: a brief description of the development of flow path and arrival time plots, information obtainable from such plots, an example of the use of the plots in determining the extent of contamination of ground water, and an example of the use of the plots in formulating a contaminant removal plan.
Ground‐Water Availability, Hockessin, Delaware
Authors: Williams Paul M. 
Published: July 2006

ABSTRACTA four‐year case study evaluation of the ground‐water availability in a small multiaquifer basin in northern Delaware has been performed to determine the hydrologic conditions when pumpage approaches the expected long‐term basin‐wide rate of ground‐water recharge. The basin is located in the Piedmont physiographic province and includes rocks of the Cockeysville marble and Wissahickon schist.Only about one‐third of the basin (the marble area) contains favorable geologic conditions for large production well development (∼ 1 MGD/well); however, the entire basin serves as a recharge area for the marble sector. The manageable storage area is limited to the marble area; consequently, accurate ground‐water recharge and storage characteristics of this basin are critical to maximizing the long‐term yield while minimizing adverse impacts of pumpage. The analysis was performed using the Thornthwaite‐Mather water balance accounting procedure to determine the long‐term significance of the exported pumpage.
Resistivity Study of a Coastal Karst Terrain, Florida
Authors: Fretwell Judy D. , Stewart Mark T. 
Published: July 2006

ABSTRACTTwenty‐eight vertical electrical soundings were completed in the west‐central Gulf Coast area of Florida. The objective of the survey was to evaluate the resistivity method for locating the fresh‐water/salt‐water interface in the karstic Floridan aquifer.Four geoelectric layers dominate the study area. The upper three are related to lithostratigraphy and correspond to: (1) surficial sands; (2) a karstic, highly‐transmissive carbonate zone; and (3) a less porous carbonate zone. The lowest layer represents a zone saturated with salt water and with a resistivity of less than one ohmmeter. Toward the coast, the fresh‐water/salt‐water interface rises, and fewer geoelectric layers are observed because pore‐water conductivity masks lithostratigraphic changes.Interface data interpreted from resistivity measurements agree with other hydrologic data. The study indicates that surface electrical methods can provide information on the interface position and can provide hydrologic information between wells used for control.
Well‐Field Drawdowns Using Coupled Aquifer Model
Authors: Motz Louis H. 
Published: July 2006

ABSTRACTWell‐field drawdowns in the Jay B. Starkey Wilderness Park in southwestern Pasco County, Florida were investigated using a coupled aquifer model developed by Motz (1978). In the model, water pumped from an underlying artesian aquifer is derived from leakage through an overlying confining bed. It is assumed that the leakage is derived from a reduction in evapotranspiration from the overlying water‐table aquifer. This process is represented by a coefficient (e) that is a linear representation of the rate at which evapotranspiration is reduced per unit of water‐table drawdown. This investigation in the Jay B. Starkey Wilderness Park provides an example of how the hydrologic coefficients in the coupled aquifer model can be calibrated from observed pumping and water‐level data and how water‐table and artesian aquifer drawdowns resulting from an increase in the pumping rate subsequently can be estimated. A value of e = 1.12 × 10−3 gpd/ft3 (1.76 × 10−9 sec−1) was obtained by matching calculated water‐table drawdowns to water‐table drawdowns attributed to the pumping effects of five production wells in the western part of the park. Five alternative plans for expanding the well field were examined, and it was recommended that the central and eastern parts of the park be developed as a well field.
Interstate Conflict Over Ground Water: Wisconsin‐Illinois
Authors: Fetter C. W. 
Published: July 2006

ABSTRACTThe Cambrian‐Ordovician aquifer (deep sandstone aquifer) of northeastern Illinois and southeastern Wisconsin consists of a number of hydraulically connected sandstone and dolomite units. The aquifer dips gently to the east beneath Lake Michigan and is regionally confined by the Maquoketa shale, which has been thinned and removed by erosion to the west. Recharge to the regional aquifer system occurs where the shale is missing and to a lesser extent across the shale wherever there are downward hydraulic gradients. The practical sustained yield from the aquifer is 46 million gallons per day (mgd) (170,000 m3/day) in Illinois and approximately 34 mgd (129,000 m3/day) in Wisconsin. In 1978, pumpage from the aquifer amounted to 142 mgd (537,000 m3/day) in the eight counties of northeastern Illinois compared with an estimated 38 mgd (144,000 m3/day) in Wisconsin. Pumpage in Illinois has exceeded the practical sustained yield every year since 1958 while in Wisconsin the practical sustained yield was reached about 1975. Two regional pumping cones have developed. One centered in the Chicago region has maximum drawdowns of more than 900 feet (275 m) while in the Milwaukee pumping cone water levels have fallen about 350 feet (106 m). The greater drawdown in the Chicago pumping cone has changed the regional hydraulic gradient and 9.3 mgd (35,200 m3/day) of ground water is now being drained from beneath Wisconsin into Illinois. A digital computer model of the aquifer system was used to separate the amount of total drawdown in the aquifer attributable to each pumping center as well as to predict future ground‐water levels. At the Illinois‐Wisconsin border in 1973, there was 265 feet (81 m) of drawdown of which 94 feet (28 m) were due to pumpage in Wisconsin and 171 feet (52 m) due to pumpage in Illinois. Allocations of Lake Michigan water to ground‐water users in Illinois could result in a reduction of pumpage to less than 46 mgd (174,000 m3/day) by 1985. In order to obtain a modification of the U.S. Supreme Court decree permitting Illinois to divert 3,200 cubic feet per second (cfs) (7,829,000 m3/day) of water from Lake Michigan, Illinois must agree that future allocations of Lake Michigan water will be done in such a manner as to reduce Cambrian‐Ordovocian aquifer pumpage. The rate of ground‐water decline will decrease substantially if this occurs. Water resources managers in southeastern Wisconsin should limit pumpage from the deep sandstone aquifer to approximately the current rate.
The Declining Ground‐Water Resources of Alluvial Valleys: A Case Study
Authors: Sophocleous Marios 
Published: July 2006

ABSTRACTThe use of ground water increased rapidly in the Pawnee Valley, Kansas, during the last two decades, causing ground‐water levels to decline and streamflow to diminish. Therefore, this study was undertaken to evaluate the impact of present and future ground‐water withdrawals in the region. This report documents the depleting water resource of the area and calculates a preliminary hydrologic budget for the region. It also adapts, automatically calibrates, and applies a mathematical model that adequately simulates the operation of the hydrogeologic system for the purpose of evaluating several schemes for managing the ground‐water resource. Two different estimates of regional ground‐water recharge in the area indicated that the average natural recharge is approximately 0.5 inch per year. On the other hand, it was found that the amount of appropriated ground water in the area exceeded the natural recharge figure by about 11 times. Digital simulations of the aquifer system indicated that, even without any additional development or with very wet periods, water‐level declines will continue indefinitely, since ground‐water withdrawals in the Pawnee Valley are of such magnitude. One option put forth for consideration is to prolong the life of the ground‐water resource through the application of all the following recommendations: concerted efforts to reduce water wasting and to increase efficiency of water use; implementation of not more than a 40 percent saturated‐thickness depletion allowance for the next several years; imposition of a freeze on the number of irrigation wells to the present levels; and engagement in an artifical‐recharge program.
Impact of Dredged Material Disposal Upon Ground‐Water Quality
Authors: Morrison Robert D. , Yu Kar Yuk 
Published: July 2006

ABSTRACTA two‐year ground‐water monitoring program at three upland dredge disposal sites in the United States was conducted to determine whether the sites were contributing to ground‐water degradation. Facilities were located at Grand Haven, Michigan, Sayreville, New Jersey, and Mobile, Alabama. Leachate samples were collected from vacuum/pressure lysimeters and ground‐water wells. Ground‐water wells were situated directly under the fill, downgradient, and in an area representative of indigeneous ground‐water quality. Analyses of 27 parameters from 10 sampling periods indicated that calcium and manganese represent major water quality problems due to their contribution to water hardness. Of the trace metals, manganese and iron were found to exceed recommended EPA drinking‐water quality standards at all sites. Levels of potassium, total organic carbon (TOC), chloride, sodium, calcium, alkalinity, and magnesium appear to affect local ground‐water quality. Possible controlling mechanisms for observed leachate concentrations for these parameters include absorption, adsorption, ion exchange complexation, dilution and biological activity.
Ground‐Water Recharge from Rectangular Areas
Authors: Rao N. H. , Sarma P.B.S. 
Published: July 2006

ABSTRACTThe formation of ground‐water mounds in response to recharge from ponds has been described earlier by equations that have been developed for infinite aquifers. In this paper, an equation for the formation of ground‐water mounds on recharge from a rectangular area to a finite aquifer was derived. The validity of the equation was tested by comparison with field data of recharge from square ponds. The solution derived here appears to describe the actual field response of water table to recharge better than the equation derived for infinite aquifers.
The Selection of a Computer for a Wide Range of Ground‐Water Related Applications
Authors: Holzschuh Joseph C. 
Published: July 2006

ABSTRACTDue to inexperience on the part of those assigned to purchase computer facilities for water resource tasks, a poor or unacceptable choice of equipment is often made. The political realities of introducing new computing equipment into a firm which has several departments which will vie for the use of that equipment must be faced.The size, complexity, and capabilities of the machine to be purchased as well as the software and personnel involved must be considered carefully in relation to the specific tasks at hand. The bidding process, demonstrations, and reference materials offer some assistance in deciding among the often confusing array of systems available on the market.
Regional Hydrogeologic Concepts of Homoclinal Flanks
Authors: LeGrand Harry E. , Pettyjohn Wayne A. 
Published: July 2006

ABSTRACTA worldwide overview of structural geologic settings indicates that the homoclinal flank is one of the most widespread and common of hydrogeologic systems. The geomorphic conditions on the structural basin flanks correlate with distinctive ground‐water flow patterns.Relatively undisturbed coastal plain formations and all other sedimentary rocks that are arched or warped into marginal basins are flanked at the land surface by dynamic hydrologie systems. Their aquifers, on a local scale considered to be horizontal, extend into regional tilted and beveled systems. Dips of strata that are only slightly greater than the gross slope of the land surface, but in the same direction, are prominent and produce exposures of alternating permeable and less permeable beveled formations in elongated regional bands. Differential erosion has led to cuesta landscapes in varying degrees. On these step‐like plateaus, subsequent and consequent streams have distinctive streamflow characteristics.One common type of hydrologic system is that dominated by consequent streams flowing down the structural basin, generally through reentrants in scarps. These streams capture much ground‐water runoff at the lowest exposed point in the aquifer (at the apex of the V that the stream makes with an overlying aquitard). The discharging ground water forms a natural cone of depression in the aquifer, representing a chief core of the ground‐water circulation system. An example is the large cone of depression in a Cretaceous sand aquifer in the Savannah River valley 15 to 25 kilometers south of Augusta, Georgia.Graphic modeling of hydrogeologic systems in homoclinal flanks explains the uneven distribution of ground‐water discharge. Stretches of each stream can be classified readily according to the degree of ground‐water discharge on a homoclinal flank.
Hydraulic Connection Between Lake Michigan and a Shallow Ground‐Water Aquifera
Authors: Cherkauer D. S. , Zvibleman B. 
Published: July 2006

ABSTRACTPumping from a dolomite aquifer adjacent to Lake Michigan has reversed the natural hydraulic gradient so that lake water has been induced to flow into the aquifer. Because lake water is muchlower in dissolved solids than the ambient ground water, the induced recharge is traceable as adistinct plume of high‐quality water over a mile long. The configuration of the plume allows interpretation of the hydraulic connection between the lake and the aquifer. Most of the induced recharge enters the aquifer through the lake bed at locations where the most permeable parts ofthe aquifer are overlain by relatively thin lake‐bed sediments which, in turn, are at least partly sand and gravel. It continues inland along zones of high hydraulic conductivity.
Inverse Solutions of the Theis Equation Determined with Programmable Calculators I—Single Parameter Calculations
Authors: Grimestad Garry 
Published: July 2006

ABSTRACTThis is the first of two articles on calculator programs for inverse solutions of the Theis equation.Newton's method is used to solve the Theis equation in terms of its principal well function argument parameters. The resulting iteration formulas are incorporated in an otherwise conventional polynomial‐based drawdown program for Hewlett Packard HP 67/97 calculators.The calculator program can solve, in addition to conventional drawdown problems, those problems requiring treatment of the time, distance, storage coefficient, or transmissivity as a dependent variable. Example calculations are shown and program modifications providing for series‐based well function calculations are appended.
Hydrochemical Facies in a Tertiary Basin in the Milligan Canyon Area, Southwest Montana
Authors: Krothe Noel C. , Bergeron Marcel P. 
Published: July 2006

ABSTRACTEquilibria studies of ground‐water chemistry in a synclinal basin at Three Forks, Montana indicate that most waters in the Tertiary sediments and Madison Group carbonates are calcium‐bicarbonate, or calcium‐sulfate waters which are supersaturated with respect to calcite. Calcium concentrations range from 13 to 426 mg/l, bicarbonate concentrations range from 112 to 328 mg/l and sulfate concentration varies between 29 to 114 mg/l. Sodium concentration is between 10 and 312 mg/l, producing sodium‐bicarbonate waters in some areas.Water‐level data were used to construct a potentiometric map that shows flow direction to the east. The water evolution along the flow path is from calcium‐bicarbonate in the recharge areas, to calcium‐sulfate in the center of the area, and finally sodium‐bicarbonate in the discharge area. This evolutionary sequence can be explained by calcite, dolomite and gypsum dissolution, ion exchange, sulfate reduction and dilution by recharging waters from the Elkhorn Mountains Volcanics.
Hydrologic Testing of Tight Zones in Southeastern New Mexico
Authors: Dennehy Kevin F. , Davis Paul A. 
Published: July 2006

ABSTRACTIncreased attention is being directed toward the investigation of tight zones in relation to the storage and disposal of hazardous wastes. Shut‐in tests, slug tests, and pressure‐slug tests are being used at the proposed Waste Isolation Pilot Plant site, located in southeastern New Mexico, to evaluate the fluid‐transmitting properties of several zones above the proposed repository zone. Apparatus used to conduct these tests includes a pressure‐transducer system connected to a recording device at the land surface. All three testing methods were used in various combinations to obtain values for the hydraulic properties of the test zones. Multiple testing on the same zone produced similar results. Transmissivities determined by these tests range from 0.00001 to 10 feet squared per day (.000001 to 1 meter squared per day).
Deviations from Classical Behaviour in Pumping Test Analysis
Authors: del Mar Gonzalez Maria , Rushton K. R. 
Published: July 2006

ABSTRACTThis paper discusses certain of the reasons for deviations from the classical type curve behaviour during pumping tests. A particular series of pumping tests in a confined limestone aquifer is considered; the tests include a step test, a 3‐day test and a 71‐day test. Using a radial flow numerical model, the influences of transmissivity, storage coefficient altering with radius, a neighbouring baseload borehole and a distant unconfined boundary are each considered. The baseload borehole is shown to have a significant effect on both abstraction and recovery response for the 3‐day test, while both the baseload borehole and the unconfined boundary modify the response for the 71‐day test.
A Method of Performing Response Tests on Highly Permeable Aquifers
Authors: Prosser Donald W. 
Published: July 2006

ABSTRACTResponse or “slug” tests to determine the hydraulic conductivity of in situ earth materials are often difficult to perform in situations of very high hydraulic conductivity. In small‐diameter standpipes, rapid response to the induced head difference, often in a matter of seconds, is difficult to measure with conventional well sounders. Instantaneous induction of a known head difference is also a major problem when dealing with very fast response times. A method of performing such tests has been developed, utilizing electronic pressure transducers to monitor the response to a pneumatically induced head. Increased air pressure within the standpipe causes displacement of the water column to accommodate the air pressure. Once the aquifer has re‐equilibrated in this condition, sudden release of the air pressure constitutes an instantaneously induced head difference. The response measured by the electronic pressure transducer can be recorded digitally or by an analog chart recorder with fast paper speed. This method has been used to measure basic time lags in the order of several seconds. The use of electronic pressure transducers and pneumatically induced head differences will allow accurate measurements in situations of higher hydraulic conductivity than would be possible using common response testing techniques.