bluuebunny/crossref_metadata_2025 huggingface dataset:
Mathematical Model Application in Ground‐Water Studies of Iran
Authors: Ghassemi F.
Published: July 2006

Mathematical models of ground‐water aquifers with complex geologic and hydrologic factors have been used effectively since 1960 in the world. In these models first the past hydrogeological conditions are simulated, then it is possible to impose on the model the future conditions by increasing, redistributed pumping, artificial recharging or many other factors which may change the existing hydro‐geological conditions.

Different numerical methods such as finite difference, finite element and dynamic programming are used in mathematical simulation of the aquifers.

The study of different aquifers in Iran by classical methods has been started systematically since 1962, and during this period more than 200 aquifers (550,000 km2 or 212,000 sq mi) are studied in reconnaissance phase and about 80 aquifers (250,000 km2 or 96,500 sq mi) in semi‐detailed phase. In 1967 the mathematical model technique was introduced to ground‐water researchers of Iran. Actually 39 aquifers are studied by 2‐ or 3‐dimensional flow models covering nearly 40,000 km2 (15,440 sq mi) of Iranian aquifers. In these studies finite difference methods are largely used, and only a few aquifers are studied by dynamic programming, but the finite element has never been used in Iran.
GEOTHERMAL POWER PRODUCTION WITH IRRIGATION WASTE WATERa
Authors: Bouwer By Herman
Published: July 2006

Abstract.

Both irrigated agriculture and areas with dry, hot‐rock formations at relatively small depth are ubiquitous in the western United States. The former produces saline percolation water, while the latter needs water to transfer the heat to the surface to enable exploitation of the geothermal energy. Thus, it seems logical to investigate the possibility of converting irrigation return flow, which often presents an environmental liability, into a useful asset by pumping it into artificially stimulated hot‐rock formations. When brought up as hot fluid, the water can then be used for generating power, producing fresh water, and/or space heating. The paper summarizes quantity and quality of irrigation return flow, various types of geothermal systems, and quantities of power and fresh water that can be derived from steam or hot water.
THE USE OF A GAMMA LOGGER TO DELINEATE GLACIAL AND BEDROCK STRATIGRAPHY IN SOUTHWESTERN OHIO
Authors: Baldwin A. Dwight , Miller James
Published: July 2006

Abstract. An evaluation was made of the usefulness of the gamma‐ray logger in delineating glacial‐drift and bedrock stratigraphy in southwestern Ohio. The logger was useful in delineating gross stratigraphic units in a glacial outwash aquifer. The gamma log also provided a clearer indication of the clay content of sand and gravel units than did the driller's log.

On the uplands, away from the valleys filled with glacial outwash, the logger could not be used to locate the thin, poorly‐sorted, interstadial sand and gravel deposits between thicker till sheets. It could, however, be used to distinguish formational contacts in the upper Cincinnatian Series.
A Method of Aquifer Testing and Its Application to an Anisotropic Inhomogeneous Multiple Aquifer System
Authors: Riha Mirko
Published: July 2006

A new method of testing anisotropic, inhomogeneous multiple aquifer systems developed by the author makes use of small diameter bore construction techniques and enables simultaneous testing of superposed aquifers and aquitards (aquicludes).

Because of the low cost of the method the hydraulic properties of the multiple aquifer system can be determined at many sites distributed throughout the area of interest, enabling simulation of the local and regional ground‐water flow conditions and other hydrological characteristics of the system.

Since its development in 1964 the technique improved and was employed in ground‐water investigations. Data and results from the inhomogeneous, anisotropic multiple aquifer system west of Melbourne are given.
Analysis of Changes in Ground‐Water Levels in a Sewered and an Unsewered Area of Nassau County, Long Island, New York
Authors: Sulam Dennis J.
Published: July 2006

From the 195O's to the early 1970's expansion of sanitary sewerage in southwest Nassau County contributed to progressive declines in ground‐water levels. Since the early 197O's, however, 10 years after the area was fully sewered, water levels have not declined significantly, which suggests that the water table may have reached a new equilibrium position. Double‐mass‐curve analyses show that during 1953‐76 the average weighted ground‐water levels in a 32‐square‐mile (83‐square‐kilometer) part of the sewered area declined 12.2 feet (3.73 meters) more than those in the unsewered area to the east. However, by 1973 this decline was 13.5 feet (4.1 meters). Finite‐difference digital‐model results indicate that 3.6 feet (1.1 meters) of the relative 1953‐76 decline was due to pumping in adjacent Queens County and that most of the remaining decline was a result of sewerage. Streamflow within the sewered area decreased in response to the lowered ground‐water levels, and ground‐water levels in the adjacent unsewered area were also lowered because of the sewerage.
Evolution of Ground‐Water Management Policy for Laramie, Wyoming, 1869‐1979
Authors: Huntoon Peter W. , Lundyb Don A.
Published: July 2006

For 110 years, Laramie, Wyoming, has obtained most of its municipal water from the Casper aquifer. As demands on the supply increased, the philosophies governing the management of the aquifer gradually changed. There has been an evolution through the following policies: (1) initial inflow‐outflow safe yield concept, (2) simple conjunctive‐use ground‐ and surface‐water system, and (3) the beginnings of a conjunctive‐use system that relies heavily on the storage properties of the aquifer.

The evolution of management policy resulted from the press of changing demands on the system rather than innovative technical or scientific insights. Most technical advice solicited by the city in the past dealt with the immediate problem of how to augment the total supply. Through experience, the city became aware of the physical response and storage properties inherent in the aquifer, and by 1940 peak demands were being met by pumpage of water from storage. The city is currently weighing the advantages of purchasing additional surface‐water rights, and has seriously asked its advisors if the aquifer can be managed solely as a peak‐use reservoir. Under the proposed regime, large volumes of water would be withdrawn periodically from storage to meet summer and drought demands, while normal demands would be met from impounded surface water in the Laramie River.
Prevalence of Enteroviruses in Ground Water of Israel
Authors: Marzouk Yosef , Goyal Sagar M. , Gerba Charles P.
Published: July 2006

Few studies have been performed on the occurrence of enterovirus contamination of ground water. In this study, 99 ground‐water samples were examined for the presence of enteroviruses, total bacteria, fecal coliforms, and fecal streptococci by standard methods. Enteroviruses were isolated from 20% of the samples. Viruses were isolated from 12 samples which contained no detectable fecal organisms per 100 ml. No statistical correlation between presence of virus and bacteriological indicators could be determined. The widespread failure of current bacteriological standards to indicate the presence of potentially pathogenic enteroviruses in ground water is an area of concern that requires more study.
Review of Leaky Artesian Aquifer Test Evaluation Methods
Authors: Walton William C.
Published: July 2006

Flow to wells in leaky artesian aquifers is intimately related to changes in aquitard storage, well storage capacity, and degree of well penetration. The manner and extent to which these and other factors affect water levels may be evaluated with aquifer test data. Families of type curves describe time‐drawdown in the aquifer and aquitard under complex aquifer and well penetration conditions. Analysis of leaky artesian aquifer test data is possible with the array of equations derived largely in the 1950's through 1970's. Erroneous data analysis will result unless complicating factors are fully recognized and taken into account. A review of leaky artesian aquifer test evaluation methods is presented in this paper together with the field application of selected methods to foster greater use of current theories.
Assessing Public Ground‐Water Supplies in Illinois
Authors: Visocky Adrian P. , Wehrmann H. Allen
Published: July 2006

Illinois aquifers furnish approximately 233 mgd (10.2 m3/s) of water to 677 public‐water supplies outside the six‐county area of northeastern Illinois. Ground water is usually obtained from sand‐and‐gravel deposits in the glacial drift or from limestone or sandstone formations in the underlying bedrock. The most favorable ground‐water conditions are found in the northern third and the southern tip of the State, while, elsewhere, major aquifers are sand‐and‐gravel deposits of the Mississippi, Illinois, buried Mahomet, Wabash, Ohio, Kaskaskia, and Embarrass valleys.

A brief review was made of data and information in the State Water Survey files for each public ground‐water supply, and an assessment was given as adequate, marginal, or deficient, in terms of present demands. Twenty‐four supplies were studied in greater detail, including calculations of aquifer sustained yields. The study indicated that 39 supplies were marginal and four were judged deficient in meeting current demands. The majority of the marginal and deficient supplies are located in the central third of the State; but so are most of the supplies (outside of north‐eastern Illinois).

The study represents the first of a three‐part plan to: (1) define problem areas and determine priorities for studies in greater detail, (2) conduct regional studies, including test drilling, in problem areas to determine how great the water resource is, and (3) determine the water resource alternatives available to public ground‐water supplies that are found to be inadequate.
Collapse Pressure of Thermoplastic Water Well Casings
Authors: Kurt Carl E.
Published: July 2006

Because of the relatively low stiffness properties of thermoplastic materials, casings made from these materials may be more susceptible to collapse. For many applications, when a surrounding material tends to support the casing, the casing resistance to collapse should be significantly increased. The Morley equations of equilibrium for two radial collapse pressure loading conditions were modified to include the support of the surrounding medium and were solved using the Galerkin method. Parametric studies were conducted for typical water well casings and restraint values. Simple collapse prediction formulas are proposed for predicting collapse for the two loading conditions considered. Collapse pressures predicted by the proposed formulas for uniform collapse pressure are approximately 25% lower than those values predicted by the current ASTM formula. Collapse pressures for linearly varying pressure were found to be 12% higher than the corresponding values for uniform pressure. When the radial stiffness of the surrounding medium is included in the analysis, the collapse pressure resistance of the casing was found to be significantly increased over the collapse resistance of an unsupported casing.
Geophysical Investigations of Ground Failure Related to Ground‐Water Withdrawal — Picacho Basin, Arizona
Authors: Jachens Robert C. , Holzer Thomas L.
Published: July 2006

Precise geophysical surveys across ground failure zones related to ground‐water withdrawal at nine sites in Picacho basin in south‐central Arizona indicate that earth fissures in alluvium near exposed bedrock are spatially associated with local gravity and magnetic anomalies ranging from local highs to convex‐upward changes in slope. We interpret the gravity anomalies, which range from 0.1 to 1 mGal with half‐widths of 50 to 300 m (160 to 980 ft), to be caused by convex‐upward irregularities in the bedrock surface underlying the alluvial aquifer. Most irregularities are inferred to be at depths less than 250 m (820 ft). Bedrock irregularities were not detected beneath failures that are more than 2 km (1.2 mi) from bedrock outcrop. The association of earth fissures with zones of variable aquifer thickness suggests that differential compaction is occurring near these fissures. Theoretical estimates, based on the finite element method, of horizontal strains generated by localized differential compaction suggest that this mechanism is the dominant source of horizontal tension causing earth fissures in Picacho basin. Our analysis indicates that tensile strains at fissures at the times of their formation ranged from 0.1 to 0.4 percent.

Prediction of the location of earth fissures near exposed bedrock in Picacho basin and in adjacent basins with similar geologic settings appears feasible by delineation of convex‐upward bedrock irregularities. Failures far from exposed bedrock, however, may not be as readily predicted on this basis. If the rheological properties and thicknesses of subsurface materials are known, prediction of the magnitude of water‐level decline required to induce sufficient differential compaction to cause failure at potential earth fissures appears feasible.
An Anomalous Occurrence of Sodium Bicarbonate Water in a Flood Plain in a Carbonate Terrane
Authors: Krothe Noel C. , Parizek Richard R.
Published: July 2006

Geochemical factors controlling water chemistry in an influent stream and adjacent flood‐plain sediments were determined during a four‐year study. The stream has a drainage basin that is similar to many streams draining carbonate terranes in the eastern United States. It receives sewage effluent, farm and urban runoff and supplies recharge to an aquifer under extensive development.

Water beneath the flood plain, springs, and channel were calcium bicarbonate as expected; however, the prevalent chemical character of soil water beneath the channel was sodium bicarbonate. HCO3 within soil water beneath the stream is three times (1,500 mg/l) that beneath the flood plain, Na+ is two orders of magnitude greater (400 mg/l), K+ reaches 10 mg/l which is twice as great while CA2+ and Mg2+ may be one‐fifth as high as concentrations beneath the flood plain with ranges from 15 to 20 mg/l and 5 to 10 mg/l respectively. Waters 3 to 7 feet (0.9 to 2.1 m) below the flood plain contain intermediate Na+ values from 25 to 75 mg/l.

Ion exchange appears to be the mechanism accounting for the sodium bicarbonate water observed under the channel. The same relationship should occur in other areas with available carbonate rock, base exchange minerals, and an organic source.
Ground‐Water Tracers — A Short Review
Authors: Davis Stanley N. , Thompson Glenn M. , Bentley Harold W. , Stiles Gary
Published: July 2006

Tracers are used widely to determine the direction and velocity of ground‐water movement. Failures of tracer tests are most commonly a result of incorrect choice of tracers, insufficient concentrations of tracers, and a lack of an understanding of the hydrogeologic system being tested. Some of the most useful general tracers are bromide chloride, rhodamine WT, and various fluorocarbons. For certain purposes, dyed clubmoss and baker's yeast have proved valuable. Many radionuclides including 3H, 82Br, and 198Au are almost ideal for numerous purposes, but radiation hazards associated with their use together with local, State, and Federal regulations have discouraged widespread field applications in recent years within the United States.
Jojoba: An Alternative to the Conflict Between Agricultural and Municipal Ground‐Water Requirements in the Tucson Area, Arizona
Authors: Foster Kennith E. , Wright N. Gene
Published: July 2006

The Tucson, Arizona, metropolitan area has 450,000 inhabitants and is expected to have nearly 800,000 inhabitants by the year 2000. Tucson is totally dependent on ground water drawn from two basin aquifer systems for its water supplies, as are agricultural, mineral and industrial operations in the area.

Municipal, agricultural, mineral and industrial ground‐water withdrawals in the two basins amount to some 376,000 acre‐feet per year (AFY). Dependable ground‐water supplies in the two basins amounts to about 80,000 AFY. Thus, the two aquifer systems are overdrafted by approximately 296,000 AFY, 80 percent of which is by irrigation agriculture.

In Arizona, ground water belongs to the owner of the land overlying the aquifer. To ensure adequate ground‐water supplies, the City of Tucson has been purchasing and retiring farmlands in one of the basins. However, litigation that reached the Arizona Supreme Court led the Court to rule that the City could pump only 2.4 AFY per acre of farmland retired. The City has retired about 12,000 acres in the basin and in 1978 withdrew some 20,000 AFY of ground water for municipal use.

Retiring these farmlands to secure water rights impacts on area economy and creates weed problems for farmers who own land near the retired lands. The City of Tucson budgets about $50,000 annually for weed control.

A possible alternative to retiring farmlands and to cultivating crops that require heavy irrigation is cultivating arid‐adapted vegetation that has economic potential. Jojoba (Simmondsia chinensis) is a shrub native to the Sonoran Desert that appears to be an economically viable arid‐land crop. It needs about 1.5 AFY per acre compared with traditional crops grown in the Southwest that have average needs of 4 AFY or more.

The economic value of jojoba is based on the oil extracted from its seeds. It is a unique, unsaturated oil composed of nonglyceride esters consisting almost entirely of straight‐chain acids and alcohols. Such oils are difficult to synthesize in commercial quantities, and the only known natural source is the sperm whale, an endangered species.

If farmers in the basin cultivated jojoba, water use could be reduced by about 2.5 AFY per acre, from 4 AFY per acre for traditional crops to 1.5 AFY for jojoba. Even if the City of Tucson had to subsidize farmers at a rate of $40 per acre for the 10 years it takes jojoba to produce economically feasible yields, the City would save more than 50 percent of the cost to purchase and retire farmlands and still be able to draw water from the basin for municipal uses.

This dual use of water in the basin would permit agriculture to continue its contribution to area economy while the City could continue meeting its water needs by piping water out of the basin into the metropolitan area. However, implementing this plan would require changing Arizona ground‐water laws.
Ground‐Water Salinity Problems Related to Irrigation in the Colorado River Basin
Authors: El‐Ashry Mohamed T.
Published: July 2006

The ground‐water system in many of the irrigated areas of the Colorado River Basin is derived almost entirely from deep percolation of irrigation water and seepage from irrigation conveyance and tail‐water collection systems. Salt pickup rates from irrigated soils in the basin vary in the different areas. Among the high salt pickup areas is the Grand Valley in western Colorado, estimated at 8 tons/acre/year. Water entering the ground‐water supply from irrigation practices in the valley amounts to about 145,000 acre‐feet/year and contributes about 690,000 tons/year to the salt load of the Colorado River. Samples of base‐flow water from the weathered Mancos Shale aquifer in the valley vary in salinity from about 1,500 to about 9,000 mg/l with a mean of 4,100 mg/l; while water samples from alluvial aquifers range from 305 to 124,000 mg/l with a mean of about 11,500 mg/l. Base‐flow returning to the river in the drains and washes has concentrations that average about 4,200 mg/l.

Water losses and quantities of irrigation return flows can be reduced by improving farm irrigation efficiencies and by partial or complete lining of canals, laterals, and ditches. Increasing on‐farm irrigation efficiency through system improvements and irrigation scheduling is the most cost‐effective measure. However, achievement of higher efficiencies will require changes in water laws to encourage conservation and revised water pricing policies that discourage waste.
Resistivity Investigations for Ground Water in Metamorphic Areas Near Dhanbad, India
Authors: Verma R. K. , Rao M. K. , Rao C. V.
Published: July 2006

Despite sufficient rainfall, large parts of Eastern India suffer from water scarcity. Ground water occurs in weathered or semiweathered/fractured layers in hard‐rock areas whose thickness varies, in general, from 5 to 20 m.

Ground‐water studies have been carried out in several areas in and around Dhanbad (Lat. 23°48′N, Long. 86°24′E) in Bihar State of India. The area covers Pre‐Cambrian hornblende and feldspathic gneisses, schists, granulites, quartzites, metabasics and pegmatities. The area forms a part of ENE‐WSW trending Satpura orogenic belt. The quartz reefs formed as fault fillings act as barriers to the flow of ground water. Geophysical investigations, using electrical methods, with Schlumberger configuration using AB up to 300 m were carried out at most of the locations. Conventional resistivity meters were used for this purpose.

The data from 78 Schlumberger soundings has been analysed. Both A and H type curves were obtained. Spectrum of resistivity values has been prepared to study the over‐all variation of resistivity values in the area. It is observed that the curves with arithmetic mean values are quite representative. The values obtained from spectral and regression analyses are nearly the same.

The results of geoelectric soundings have been compared with the geological section wherever available. It is inferred that the thickness of the weathered layer as deduced from Schlumberger soundings includes partly the unweathered/fractured layer as well. An attempt has been made to find an empirical relationship between the daily yield of water in gallons/day and the longitudinal conductance (s = h/p) of the weathered layer. Two empirical relationships have been obtained, one for the winter months, December‐January and the other for the summer months, June‐July. A suitable explanation for the two curves has been given.
Computationally Efficient Polynomial Approximations Used to Program the Theis Equation
Authors: Huntoon Peter W.
Published: July 2006

Polynomial approximations have been developed for the infinite series embodied in the Theis equation. These have the following advantages when programmed for use on computers or hand calculators: (1) they are easy to program; (2) they are computationally efficient; and (3) they eliminate round‐off errors.
Determination of Aquifer Parameters from Step Tests and Intermittent Pumping Data
Authors: Birsoy Yuksel K. , Summers W. K.
Published: July 2006

The expression

image

is a handy tool for predicting aquifer parameters using all the drawdown and recovery data obtained during step‐drawdown tests or periods of cyclic or intermittent pumping.

For inefficient wells the expression

image

fits pumping wells better. The data from conventional step‐drawdown tests of pumping wells can be used to obtain T, C, and y. If the data fail to fit the ideal, they may be used to interpret local hydrologic conditions.
A Comparative Study of Nitrate Levels at Three Adjacent Ground‐Water Sources in a Chalk Catchment Area West of London
Authors: Gray E. M. , Morgan‐Jones M.
Published: July 2006

A comparison of the concentrations of nitrate in three public supply borehole sources which abstract water from the Chalk in a relatively local area, led to a more detailed study of the possible causes of high nitrate values at one of the sources and the geological and recharge characteristics of all three.

The local catchment area of the high nitrate source is actively fertilized, both by sludge spreading and the application of artificial fertilizers. The catchment areas of the other two ground‐water sources are not subject to the same intensive agricultural activity. It is suggested the differences in water quality between the three supplies are related to the variations in land use and the local hydrogeology.

The study makes it clear that due to local influences each source may have a unique hydrogeochemical character irrespective of being located in the same regional geological catchment area.

More detailed investigations on the origins of the nitrate in the abstracted ground waters are planned as a follow‐up to this initial study.
Use of Microcomputers in Ground‐Water Basin Modelinga
Authors: Mido Kiyoshi W.
Published: July 2006

It has been demonstrated that a microcomputer costing less than $10,000 can accommodate a ground‐water basin model with a large number of nodes. Analyses indicate that finite difference and finite element models with several hundred nodes also can be accommodated. Microcomputers have several advantages over the larger and much more expensive macrocomputers as ground‐water basin modeling tools: easy to learn language used for programming, simplicity of operation, and low costs leading to easy access by investigators and users. Because of these advantages, willing investigators can learn to do modeling work by using a microcomputer and also write programsto computerize time‐consuming tasks and thus effect substantial manpower cost savings.
Distribution and Probable Source of Nitrate in Ground Water of Paradise Valley, Arizona
Authors: Silver Burr A. , Fielden John R.
Published: July 2006

Field investigations in Paradise Valley, Arizona, conducted during 1974 and 1977, delineated areas of ground water with up to 132 mg/1 nitrate. Two alternative interpretations are developed as to possible sources of the excess nitrate. The first is a conventional interpretation identifying the use of nitrogenous fertilizers as the primary source and disposal of treated waste‐water effluent as a secondary source. An alternative interpretation identifies the source as a sand and gravel unit that is interpreted as a braided‐stream deposit, located about 152 m (500 ft) below the land surface. The source of the nitrate may have been NH4Cl leached from tuffs in the adjacent Superstition Mountains, subsequently oxidized to nitrate and deposited in abandoned channels of the braided‐stream complex. At present, it is not possible to make a definitive choice among the possible nitrate sources.
Well‐Water Quality Changes Correlated with Well Pumping Time and Aquifer Parameters—Fresno, Californiaa
Authors: Nightingale Harry I. , Bianchi William C.
Published: July 2006

Ground‐water chemical quality in alluvial valleys can be stratified, which can cause well‐water quality to vary with pumping time, especially after a pump shutdown of several hours. These changes in chemical quality could have public health implications for automatically controlled high‐capacity municipal water wells that pump directly into the distribution mains.

For a large number of municipal wells, the shapes of the curves for the change‐in‐specific electrical conductivity and the NO3‐N content of well water during the first 96 minutes of constant rate pumping are reported after a 24‐hour shutdown as compared with “steady‐state” quality. The variables recovery‐transmissivity, well specific capacity, type of well construction, and equivalent specific yield of aquifer computed from driller's logs of the bore holes were considered in the analysis.

The results showed that well‐water quality vs. time curves vary in shape and are related mainly to the well depth and the depth to the perforations. The “steady‐state” specific electrical conductivity and NO3‐N values were significantly correlated to each other and inversely to recovery‐transmissivity and equivalent specific yield. The specific capacity of wells was related to the recovery‐transmissivity and to type of well construction.
A NOTE ON POSSIBLE USE OF MICROCOMPUTERS FOR AQUIFER STUDIES
Authors: Risner Jeffrey K.
Published: July 2006

Abstract. Microcomputers can be a major tool for the hydrologist. Small and portable, microcomputers can be useful for the acquisition and modeling of an aquifer while on site. This would result in very low cost for computer usage and fast processing time. Their low cost makes the availability almost universal. Tests were run on the TRS‐80 system using the Prickett finite difference model and the Theis equation. The results indicate that with the exception of memory storage no problems should arise. With newer generations of microcomputers core memory storage will no longer be a problem.
THE “CHEAT SHEET”: A NEW TOOL FOR THE FIELD EVALUATION OF WELLS BY STEP‐TESTING
Authors: Kelly Jack E. , Anderson Keith E.
Published: July 2006

Step‐testing of wells penetrating a jointed, fractured, sometimes cavernous limestone‐dolomite artesian aquifer showed characteristic patterns of extreme variation in specific capacity at different discharge rates. The application of principles developed by Jacob for well‐loss determinations, and subsequent modifications by others, did not yield meaningful results. It was found that a log‐log relationship between discharge and drawdown, through a large number of steps, could be used to evaluate the degree of nonlinear head losses in and near the well bore and make possible the extrapolation of drawdowns at higher discharge rates. This technique also has been used to estimate transmissivity which, in at least one instance, was confirmed by the subsequent evaluation of observation‐well data by both straight‐line and type‐curve methods. The easy use and rapid initial evaluation of test data afforded by this method gave rise to the name “Cheat Sheet.”
Experimental Determination of Thermoplastic Casing Collapse Pressures
Authors: Johnson Roy C. , Kurt Carl E. , Dunham George F.
Published: July 2006

A major potential failure mode of thermoplastic well casing is collapse. The casing may be subjected to a collapsing pressure during grouting operations, backfilling, well development or simply from lateral soil pressure. Since the strength of thermoplastic materials significantly decreases at elevated temperatures, it is important to know how casing collapse resistance varies with temperature.

A series of experiments have been performed to determine the collapse resistance of poly (vinyl chloride) (PVC) and acrilonitrile‐butadiene‐styrene (ABS) well casing over a wide range of temperature. Results indicate that collapse resistance is inversely proportional to a function of the outside diameter‐to‐wall thickness ratio as indicated in the ASTM F480 standard and that collapse resistance decreases by approximately ½ psi per degree Fahrenheit increase in temperature above room temperature.
Problems of Rationally Draining the Poleyes Marshesa
Authors: Petrov Ye. G.
Published: July 2006

Comprehensive, steady‐state investigations were carried out on plots adjoining drained tracts in Byelorussia's southern marshified lowlands, plots encompassing different plant cover, types of soil and ground‐water levels, to ascertain the influence of ground‐water level and its fluctuations on the formulation and productiveness of forest, field and meadow verdure.

It was established that when the ground‐water level diverged—higher or lower—from optimum (i.e., depth approximately equal to the height of the capillary lift), productiveness of plants fell; that intensive utilization and drying of peat bog soils led, as a rule, to mineralization of the peat and air and water erosion (the lower the level falls the more intensively mineralization proceeds). It is calculated that with cultivated crops the loss of peat is some 10 tons per hectare per year, 5‐6 with cereals and 2‐3 with grasses.

Lowering the ground‐water level on any area leads to changed levels on adjacent areas, the ground waters being elements of a unified system. In the sandy soils most widespread in the Byelorussian lowlands, lowering of ground‐water level perceptible in the vital activities of plants occurs up to 2 kilometers from the drained tract. In all cases reductions in ground‐water level and in the duration and height of flooding led to degradation of the meadows.

It is concluded that comprehensive calculations on the possible harmful effects of drainage reclamation‐caused changes in a large territory's hydrological regime are a prerequisite for rational utilization of the land and maximum productiveness and preservation of the natural landscape.
Programmable Hand Calculator Programs for Pumping and Injection Wells:
Authors: Warner Don L. , Yow M. Gene
Published: July 2006

Programmable calculator programs have been given previously for the calculation of head or pressure change resulting from the pumping from or injection into wells completely penetrating fully confined or semiconfined aquifers. Programs are documented here for wells partially penetrating a fully confined aquifer. The programs are for the TI 59 card programmable calculator.
Computer Models in Ground‐Water Exploration
Authors: Remson Irwin , Gorelick Steven M. , Fliegner Julianne F.
Published: July 2006

Four case histories illustrate the various roles that digital computer simulation models can play in ground‐water exploration. The case histories describe their use in evaluating aquifer parameters and characteristics, in estimating ground‐water recharge, in resolving data inconsistencies, and in determining the optimal allocation of exploration funds. The models are especially useful in identifying data deficiencies and inconsistencies.
GEOTECHNICAL INVESTIGATIONS DURING DRILLING OF A DEEP DISPOSAL WELL IN DADE COUNTY, FLORIDA
Authors: Singh Udai P. , Sprout C. Ross
Published: July 2006

.

A test‐injection well was drilled to a depth of 3,200 feet (976 m) to determine the feasibility of deep underground injection of 50 mgd (190,000 m 3/day) ADF of secondary treated waste water in south Dade County, Florida. Geological formation samples and water samples were collected and analyzed during the drilling of the well and geophysical logging was performed in the well at several stages. At this site, the Floridan aquifer extends from a depth of 920 feet (281 m) to 1,680 feet (512 m) and generally consists of limestone which is fossiliferous in part. Water from this aquifer is brackish, with chlorides ranging from 700 mg/l at the top to 15,000 mg/l at the bottom. The strata from 1,680 feet (512 m) to 2,790 feet (851 m) are essentially nonwater‐producing and act as a confining bed between the Floridan aquifer and the Boulder Zone.

The Boulder Zone begins at 2,790 feet (851 m) in depth and consists of a very hard, fractured, cavernous, dark dolomite. The water from this aquifer is very similar to sea water. The subsurface temperature gradient at this site is reversed from the normal gradient, cooling with depth at an average rate of approximately 0.4° F (0.22°C) per 100 feet (30 m). The injection zone extends from approximately 2,830 feet (863 m) to 2,920 feet (891 m) in depth. Results of pumping tests indicate that the Boulder Zone is very transmissive and has a good confining bed above it.
AN OCCURRENCE OF CALCIUM HYDROXIDE GROUND WATER IN JORDAN
Authors: Saines Marvin , Dickson Peter , Lambert Paul
Published: July 2006

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Calcium hydroxide ground‐water seepage, highly mineralized, with a pH measured as high as 12.7 has been discovered in the Yarmouk Valley of Jordan. The origin of the seepage is rainfall recharge through over 100 meters of portlandite‐rich rock. The portlandite [Ca(OH)2] was formed by thermal metamorphism of calcite due to (spontaneous) combustion of organic‐rich marl and limestone. The pH is believed to be the highest ever reported for natural ground water.
Modification of an Electronic Downhole Water Sampler
Authors: Idler Gerald E.
Published: July 2006

A common problem with a downhole water sampler consisting of a reservoir for fluids and a remote controlled motor‐operated piston valve assembly has been sample contamination due to damage or destruction of the O‐ring seal on the piston of the sampler. O‐ring damage results from shaving by sharp edges in the entry‐ports area or from erosion by high fluid velocities through the entry ports when sampling at depths below water level greater than 2,500 feet (762 meters). Beveling of sharp edges in the entry ports and modification of the piston by installation of a needle valve and seat solved the problem of O‐ring damage and resultant loss of sample integrity. Other modifications include a high pressure needle valve in the removable reservoir chamber bottom that allows the reservoir to be drained while pressurized, and an O‐ring piston in the reservoir chamber that permits collection of water samples that are essentially free from contamination by surface air. With the latter modifications, the sampler can also be used for injecting brine or other tracers in quantities as large as 34 fluid ounces (1 liter).
Growth of Ground‐Water Mound in Response to Recharge
Authors: Rao N. H. , Sarma P.B.S.
Published: July 2006

It was proposed that the horizontal extent of the ground‐water mound is limited for finite times of recharge from strip basins even in infinite aquifers. A method of identifying the extent of the ground‐water mound using solutions of the equation of flow for finite aquifers was suggested. These solutions were obtained using two different procedures of linearization, those of Baumann and Hantush, and Laplace transforms. The resulting expressions were of a general nature and the equations of Hantush for infinite aquifers were shown to follow as a special case. The range of validity of the two procedures of linearization was tested using experimental results from sand tank models of finite aquifers, available in literature. The Baumann linearization was valid (correct to within ±5 percent of experimental values) up to a water table rise less than 0.4 times the initial height of the water table. The Hantush linearization was valid (correct to within ±2 percent of experimental values) for the entire range of water table rise studied, i.e. up to three times the initial height of the water table. The Hantush procedure was thus shown to have wider applicability. However, both procedures were found to yield results which have satisfactory agreement with experimental results over larger ranges than earlier reported for infinite aquifers.

The effect of variation of the horizontal extent of the recharge mound on the water table profile was studied by treating the limit of the horizontal mound itself as a parameter. The water table rise was computed using the Hantush linearization procedure for different values of the ratio B/L (B/L = 15, 20, 25, 30, 35, 40 and ∞) where 2B is the horizontal extent of the mound and 2L the width of the recharge strip. The finite extent of the ground‐water mound in an infinite aquifer was given by that value of B/L for which the predicted profile was identical to that produced when B/L =∞.
Ground‐Water Quality Changes During Exploitation
Authors: Blaszyk Tadeusz , Gorski Josef
Published: July 2006

Considerable changes in water quality have been observed in ground water pumped from wells in quaternary formations in Poland. These changes include increases in dissolved calcium, sulfate, iron and manganese.

Experimental results indicate that dissolved‐solids' increases are influenced by the introduction of oxygen into the hydrogeochemical environment during pumping.

The oxidation of sulfur compounds produces acid, which increases the solubility of numerous chemical compounds. Bacterial catalysis of some reactions is indicated.
THE EUROPEAN COMMUNITY EVALUATES ITS GROUND‐WATER RESOURCES
Authors: Fried J. J.
Published: July 2006

The Commission of European Communities has completed the evaluation of the ground‐water resources of the Community. Directed by the author, the study is the first multinational water resources evaluation, performed by nine consultants representing the nine Member States. Comprising 152 maps at the scale of 1/500,000 and ten reports, it appears to be the first complete survey of ground water at that scale for most Member States.
WASTE IMPOUNDMENT ASSESSMENT IN THE STATE OF INDIANA
Authors: Walsh J. J. , Gillespie D. P. , Schauf F. J. , Silka L. R.
Published: July 2006

A waste impoundment is a pit, pond, or lagoon used for the storage, treatment, or disposal of wastes. Because they may contain hazardous wastes and are often sited in permeable soils, waste impoundments pose athreat to the nation's ground‐water resources. Out of the need for better protection of ground water, a nationwide program on waste impoundments was developed by the U.S. Environ mental Protection Agency (EPA). The purpose of this study was to develop a data base on impoundment numbers, locations, operations, and contamination potential which would aid in the establishment of an appropriate ground‐water protection program.

The primary objectives of the Indiana waste impoundment project included: (1) to perform an inventory of waste impoundments in the State through file reviews and inspector interviews, and (2) to rate each waste impoundment inventoried on the basis of its ground‐water contamination potential.

Data collected on this project demonstrate that waste impoundments do pose high contamination potentials. For example, depths to ground water at impoundments averaged only 13 ft (3.8 m) and approximately 20 percent of impoundments are located atop sand and gravel or limestone. Furthermore, 1,781 sites (94 percent) are within 1 mile (1.6 km) of water supplies and 95 (5 percent) of these are less than 600 ft (220 m) upgradient from drinking‐water wells.
FLOWMETER ANALYSIS AT RAFT RIVER, IDAHO
Authors: Schimschal Ulrich
Published: July 2006

A quantitative evaluation of borehole‐impeller flowmeter data leads to estimated field hydraulic conductivity. Data were obtained during an injection test of a geothermal well at the Raft River geothermal test site in Idaho. Both stationary and trolling calibrations of the flowmeter were made in the well. Methods were developed to adjust for variations in hole diameter, impeller speed, and trolling speed. These methods were applied to evaluate water losses into the formation as a function of depth. Application of the techniques is restricted to aquifers below the water table. The flowmeter data were digitized and processed by the computer to obtain plots of apparent field hydraulic conductivity versus depth.
Predictive Depositional Model for Glacial Aquifers
Authors: Stewart Mark T.
Published: July 2006

In an investigation of the hydrogeology of bedrock valley fills in northeastern Wisconsin, it was determined that the yield and spatial distribution of glacial aquifers are controlled by bedrock topography and glacial geology. Lithologic control for identification and classification of aquifer units was obtained from several hundred drillers' logs calibrated by auger borings and interviews. Transmissivities of drift aquifers calculated from specific capacity tests using Jacob's equation agree well with estimates made from lithologic logs. Seismic refraction and gravity surveys were coupled with well log data to derive a bedrock elevation map. Vertical variability maps calculated from the lithologic logs show that bedrock topography strongly influences the distribution and character of glacial units, and clearly delineate the two glacial aquifer types present, valley and morainal units. Morainal units parallel the Late Wisconsin end moraine trends, while valley units are perpendicular to the moraines. The morainal units are small ice‐contact features such as kames, fans, and deltas. The valley units are stream deposits and may have been deposited subglacially. Valley aquifers are the most productive units. Using lithologic and geophysical data, and statistical analysis, a predictive depositional model can be proposed. This conceptual model allows knowledge of bedrock topography to be coupled with glacial geology to predict the spatial distribution of glacial aquifers.
Analysis of Pumping Test Data Using Marquardt Algorithm
Authors: Chander Subhash , Kapoor P. N. , Goyal S. K.
Published: July 2006

Marquardt algorithm has been used for estimating aquifer parameters from pump test data in nonleaky and leaky aquifers. It emerges from the study that in spite of poor initial estimates, the convergence is quick; and the residual square error, for the difference between the observed drawdowns and those calculated from parameters estimated using Marquardt algorithm and the known methods, is minimum in the case of Marquardt estimates.
Estimation of Calcium Sulfate Solution Rate and Effective Aquifer Surface Area in a Ground‐Water System Near Carlsbad, New Mexico
Authors: Claassen Hans C.
Published: July 2006

The geochemistry of a very permeable ground‐water system containing calcium sulfate was studied to determine the present rate of dissolution. An estimate was made of the chemical composition of water recharging the system and the difference between that estimate and the composition of the ground water in the system was used to determine the minimum amount of calcium sulfate being dissolved under existing hydrologic conditions. This result was used, with published data on rates of calcium‐sulfate dissolution, to determine the effective surface area involved in solution processes. Results indicate that flow in this system is through large solution openings, which are growing larger at a rate of a few tens of millimeters per year.
Atoll Island Hydrology
Authors: Wheatcraft Stephen W. , Buddemeier Robert W.
Published: July 2006

Enjebi Island on Enewetak Atoll has been the site of extensive hydrological, geological and geophysical studies. Tidal lag, tidal efficiency and water levels have been measured in 24 wells ranging in depth from one m to 90 m (3–290 ft). Hydraulic conductivity has been measured both on laboratory samples and by aquifer testing in the field. Theoretical ground‐water tidal responses have been calculated using a model based on horizontal propagation of tidal signals. Comparison of field observations and model results indicates that the observed results are not consistent with horizontal tidal propagation and that the hydraulics of the system are probably controlled by vertical coupling between the unconsolidated surface aquifer and an underlying aquifer of more permeable limestone. Results from other islands of Enewetak, Bikini and Kwajelein Atolls are comparable, and suggest that vertical transport between layered aquifers is an important feature of atoll ground‐water hydrology at least throughout the northern Marshall Islands.
A PRELIMINARY SURVEY OF STATE GROUND‐WATER LAWS
Authors: Wickersham Ginia
Published: July 2006

A preliminary survey of ground‐water laws in 24 States reveals a variety of control measures being utilized to manage the nation's ground‐water resources. One important technique is the establishment of ground‐water quality standards. Four States and one territory presently have ground‐water quality standards in effect. Other control measures include well permits, limits on use, designation of critical areas, and licensing of well drillers.

New comprehensive ground‐water legislation is being considered in western States, particularly California and Arizona. In California, the emphasis is on continued local control. In Arizona, a new ground‐water law requires strict mandatory conservation for the entire State. The Arizona Ground Water Management Act, if successful, may be a model law for other States to emulate.
An Assessment of Current Standards for Selenium in Drinking Water
Authors: Hammer Mark J.
Published: July 2006

Selenium is a trace metal naturally occurring in soils derived from some sedimentary rocks. Upon oxidation to the selenate ion, it can percolate to ground water and be assimilated by plants. Effects upon human health have not been clearly established—a low selenium diet is beneficial, while high doses can produce undesirable physical manifestations. Neither extreme dietary deficiency nor toxicity is apparent in the human population of the United States. The maximum contaminant level of 10 μg/1 adopted in the National Interim Primary Drinking Water Regulations is not justified by recent studies and should not be enforced by the Environmental Protection Agency without new scientific evidence demonstrating that naturally occurring selenium is a health hazard.0