bluuebunny/crossref_metadata_2025_split huggingface dataset:
Surface and Borehole Geophysical Methods in Ground Water Investigations
Authors: Mickam James T. , Levy Benjamin S. , Lee George W. 
Published: February 2007

AbstractGround water flow in karst terranes generally occurs in the solution channels of carbonate aquifers. A hydrogeologist may utilize borehole geophysical methods to identify these solution channels in aquifers. Two specific methods that are applicable in karst terrains are:1. Natural gamma ray logging2. Borehole caliper logging.Gamma ray logging can detect the presence of inter‐bedded strata in the main limestone unit, such as shale, which emit high levels of gamma radiation. Gamma ray logging can also detect clay deposits in solution channels that may act to restrict the flow of ground water. The areal extent of these rock strata or clay‐filled solution channels can be determined when gamma ray logs are conducted at several borehole locations across the site of investigation.Borehole caliper logging can be employed to determine the presences of solution channels within the aquifer when penetrated by a borehole. In addition, since shale layers and clay filling are less resistant than the surrounding limestone, the caliper log may detect both the presence and the thickness of shale or clay layers in the aquifer.Gamma ray logs can be used in conjunction with caliper logs to provide data on the stratigraphic location and thickness of solution channels and clay and shale layers within a limestone aquifer. This information is valuable to the hydrogeologist performing investigations at sites located in limestone terranes because ground water flow preferentially occurs along solution channels.
Constraints and Categories of Vadose Zone Monitoring Devices
Authors: Everett Lorne G. , Hoylman Edward W. , Wilson L. Graham , McMillion Leslie G. 
Published: February 2007

AbstractTraditional monitoring methods using chemical analysis of ground water samples to detect pollutant migration are being superseded or used in conjunction with innovative approaches. A need to detect pollutants before they reach the water table has drawn interest to vadose (unsaturated) zone monitoring and brought together hydrogeologists, soil scientists and agricultural engineers who have been working on this subject for years.Recent studies have identified over 50 different types of vadose zone monitoring devices and methods that have optimum utility in varying hydrogeologic settings. In general, measurements made in the vadose zone are trying to define storage, transmission of liquid waste in terms of flux and velocity, and pollutant mobility.Criteria for the selection of alternative vadose zone monitoring methods are important for the development of site‐specific systems. These criteria include: type of site; applicability to new, active, and abandoned sites; power requirements; depth limitations; multiple use capability; type of data collection system; reliability and life expectancy; degree of operational complexity; direct versus indirect methods; applicability to alternate media; effect on flow regime; and effect of hazardous waste on sampling or measurements. Application of the selection criteria is discussed in Everett et al. (1982a).
Developing Objectives for the Ground Water Quality Monitoring Network of the Salinas River
Authors: Showalter Patricia 
Published: February 2007

AbstractThis article describes how objectives were developed and applied to design a ground water quality monitoring network for the Salinas River drainage basin in central California. Four agencies worked together: the USGS as network designer, the Central Coast Regional Water Quality Control Board as network manager, and Monterey and San Luis Obispo county agencies as data providers. After investigating the basin's ground water quality problems, a list of objectives was developed. These objectives were written as concise statements. The network designers and managers arranged the objectives in the order of importance and set priorities for them. An ideal network was designed to meet all of the monitoring objectives. In the ideal network exercise, budget and manpower constraints were ignored. Each monitoring location was chosen for a specific objective or group of objectives. The ideal network was compared with the existing network to identify where both more and less monitoring was needed. Then a proposed network was chosen. The ideal and existing networks were composited to produce the proposed network, but budget and manpower were considered. To keep the network at a realistic size, monitoring was only recommended to meet the most important objectives. Existing monitoring sites were retained to meet any of the objectives.
Control of Ground Water Contamination at an Active Uranium Mill
Authors: White Richard B. , Gainer Randolph B. 
Published: February 2007

AbstractSeepage from tailings ponds associated with an active uranium mill in Utah has resulted in contamination of ground water contained in the Dakota‐Burro Canyon Formation. This aquifer is used in the area as a supply for domestic and industrial wells.Results of very low‐frequency electromagnetic surveys and ground water quality investigations at the site indicated that the flow of ground water and contaminants is primarily fracture‐controlled. Pumping tests were conducted to determine the hydraulic characteristics of the fractured system. The extent of contaminant migration was then determined using an analytical model of transport in fractured aquifers.Based on these investigations, a plan was designed to control future and remediate past ground water contamination. This plan consists of pumping from a single well intersecting the main fracture that transports contaminants off the site. The effectiveness of the plan was analytically modeled, taking account of the anisotropy of the ground water system. Subsequent monitoring of water levels in the area indicates that the plan has been effective since its inception in November 1983.
Factors Requiring Resolution in Installing Vadose Zone Monitoring Systems
Authors: Robbins Gary A. , Gemmell Michael M. 
Published: February 2007

AbstractIncreasingly, regulations by federal, state and local agencies are being developed that require the installation of vadose zone monitoring systems for hazardous chemical facilities in addition to, or in lieu of, conventional ground water monitoring wells. Compared to a ground water monitoring approach, vadose zone monitoring systems may permit earlier detection of chemical leakage and less costly cleanup of contamination. The effective use of vadose zone monitoring systems in detecting contamination depends on many factors. Without proper consideration of these factors, a vadose zone monitoring system may not give as high a level of reliability as a ground water monitoring system.Major factors to consider in installing a vadose zone monitoring system are: type of instrument to use, number of instruments, depth and location of instruments, and frequency of monitoring. Means to evaluate these factors in a comprehensive fashion have been lacking. Based on recent experience in installing and operating vadose zone monitoring systems, criteria and methods useful in resolving the preceding factors have been developed. Types of instruments can be classified as either direct (lysimeter, vapor probe) or indirect (tensiometer, conductivity probe). A combination of the two is needed for reliability. The depth, location and number of instruments depend on the geometry of the facility, the number and size of likely contaminant leakage points in engineered barriers, properties of the material being monitored, the effective radius of monitoring for each instrument, vadose zone properties, and types of remedial actions that are available. The freqency of monitoring largely depends on the rate of movement of the contaminant. Evaluating the preceding factors requires some level of modeling and preliminary field testing.
Underground Storage Tank Monitoring: Observation Well Based Systems
Authors: Scheinfeld Raymond A. , Robertson John B. , Schwendeman Todd G. 
Published: February 2007

AbstractA growing number of state and local governments and petroleum‐related companies require the use of release detection systems for underground petroleum storage tanks. This has resulted in a confusing array of commercially available petroleum product detection devices, many of which have not been extensively field‐tested. These systems, which are installed in ground water observation wells, vapor wells or U‐tubes, include hydrocarbon‐detecting paste, bailers, interface probes, electrical resistivity sensors, thermal‐conductivity sensors, hydrocarbon‐soluble devices, hydrocarbon‐permeable materials and vapor detectors. This paper describes the available state‐of‐the‐art technology for leak detection and the application for which each system is best suited.
Practical Application of Theoretical Models to Magnetometer Surveys on Hazardous Waste Disposal Sites — A Case History
Authors: Gilkeson Robert H. , Heigold Paul C. , Laymon Douglas E. 
Published: February 2007

AbstractWastes were to be exhumed and removed from a hazardous and chemical waste disposal site. The major disposal practice was shallow burial of wastes in metal drums in parallel trenches. The actual boundaries of the trenches beneath the landscaped cover were not accurately known.Theoretical two‐dimensional models were used to evaluate the application of magnetic methods to define trench boundaries on the disposal site. The models predicted that both the total field and the vertical component anomalies were diagnostic; however, the vertical component anomaly was more focused on the trench boundaries.A survey with a vertical component fluxgate magnetometer was successful in defining trench boundaries. Observations made along traverses that trended perpendicular to the long axis of the parallel trenches indicated vertical magnetic intensity values with a cyclical pattern of large positive values over trenches and large negative values over intertrench corridors. Vertical magnetic intensity values determined with theoretical two‐dimensional models compared favorably to the observed vertical magnetic values. The models were used to constrain the interpretation of the field observations to define trench boundaries; the magnetic survey defined trench boundaries with an accuracy within ± 2 feet.
Low‐Cost Apparatus for On‐Site Monitoring of Methane in Ground Water
Authors: Harrison Samuel S. 
Published: February 2007

AbstractAn upsurge in oil‐ and gas‐well drilling in northwestern Pennsylvania and western New York has been accompanied by several incidents of contamination of ground water by methane. Determining which well is causing the contamination is extremely difficult if more than one gas or oil well is present in the area.The fact that the solubility of methane decreases as the pressure on ground water decreases provides a quantitative basis for monitoring changes in the amount of methane in the ground water. Quantitative measurements of the volume of methane given off by ground water pumped from a well as the water enters atmospheric pressure permit detection of temporal changes in the gas content which are too subtle to be detected visually. These gas volume changes may, in some cases, be correlated with variations in the pressure of methane in the annulus of nearby individual gas/oil wells and thus may provide a means of pinpointing the gas/oil well that is causing the methane contamination.The basic principle of the gas‐volume monitoring apparatus (GVMA) described in this paper is that as a measured amount of ground water enters atmospheric pressure the gas which comes out of solution is trapped and measured. The GVMA can be constructed of materials costing less than $100 and requires no special skills to assemble or operate. In a recent study conducted in a western New York village, four homeowners were able to collect quantitative gas‐volume data from their household water wells daily in about one‐half hour. Unlike laboratory analyses for dissolved methane, there is no cost involved in monitoring with the GVMA beyond the initial instrument cost and operator time. Another advantage is that the data are available immediately.
Micro Computers Applied to Ground Water Monitoring and Testing
Authors: Brqnnaka Larry K. , Keefe Lawrence R. 
Published: February 2007

AbstractMicro computers have been demonstrated to be a most valuable, cost‐effective means of long‐ and short‐term data acquisition for ground water investigations and installations. A system can readily be assembled for the cost of labor saved in the field, or for the same cost as other conventional instruments, which perform only a fraction of the functions of the computer systemDocumented in this article are systems which have been developed and used for simultaneous monitoring of several wells during aquifer tests, and systems installed for long‐term monitoring of piezometric surface fluctuations. Both systems can be contained in a small suitcase or insulated cooler. Specific features of the systems include multiple channel capacity, one‐month maintenance period, variable computer controlled reading intervals, magnetic tape data storage, data reduction and analysis capabilities while maintaining monitoring, graphic display of time and measurements, hard copy capability and barometric pressure change corrections.Other applications are examined for the complete control of pumping tests, including pumping rate; in situ permeability tests; monitoring changes; and even strain. The pressure transducer system may also be applied for river gauging and current measurement.
Drilling and Constructing Monitoring Wells with Hollow‐Stem Augers Part 1: Drilling Considerations
Authors: Hackett Glen 
Published: February 2007

AbstractHollow‐stem augers are a widely used drilling method for constructing monitoring wells in unconsolidated materials. The drilling procedures used when constructing monitoring wells with hollow‐stem augers, however, are neither standardized nor thoroughly documented in the published literature.Variations in drilling procedures and techniques may occur as a result of the: (1) type of auger drill equipment and formation samplers used; (2) hydrogeologic conditions at the site, especially where heaving sands occur; and (3) known or suspected presence of contaminated zones, where there is a potential for the vertical movement of contaminants within the borehole.In a saturated zone in which heaving sands occur, changes in equipment and drilling techniques are required to provide a positive pressure head of water within the auger column. This may require the addition of clean water or other drilling fluid inside the augers.When monitoring the quality of ground water below a known contaminated zone, hollow‐stem auger drilling may not be advisable unless protective surface casing can be installed. Depending on the site hydrogeology, conventional hollow‐stem auger drilling techniques alone may not be adequate for the installation of the protective surface casing. A hybrid drilling method may be needed that combines conventional hollow‐stem auger drilling with a casing driving technique that advances the borehole and surface casing simultaneously.
Potential for Solute Retardation on Monitoring Well Sand Packs and Its Effect on Purging Requirements for Ground Water Sampling
Authors: Palmer Carl D. , Keely Joseph F. , Fish William 
Published: February 2007

AbstractMonitoring well sand packs are theoretically capable of retarding metal ions and organic contaminants. If this retardation does indeed occur it may have a significant effect on the purging requirements of newly installed monitoring wells. Calculations based on mass balance and retardation concepts demonstrate that if common guidelines for well purging are followed, contaminants may not be detected or may be detected in lower concentrations than are actually present in the ground water. This problem is greatest in relatively shallow wells installed in low to moderate permeability materials. In most cases, the effect of solute retardation in the sand pack can be avoided simply by additional purging prior to the first sampling of the monitoring well. Common purging guidelines can then be applied to subsequent samplings. The methodology outlined in this paper can be used to calculate the purging requirements of existing monitoring wells or it may be applied to alternative monitoring well designs to test which will require the smallest volume of purged water.
Chlorine Disinfection of Ground Water Obtained from 200M Deep Wells
Authors: Wickramanayake G.B. , Rajput V. S. , Polprasert C. 
Published: February 2007

AbstractThe effect of chlorine concentration, ground water pH, and contact time on chlorine demand and the inactivation of coliform bacteria, Escherichia coli, was studied in the laboratory using a batch reactor under controlled environmental conditions. Ground water for this study was obtained from 200m deep wells in Bangkok, Thailand. The test results demonstrate that the kinetics of chlorine inactivation of coliforms in ground water consist of an initial rapid kill rate followed by a slower rate. Disinfection was more effective in acidic pH (5.5) than basic pH (8.5). Chlorine demand exerted by ground water increased with chlorine dose, contact time, and hydrogen ion concentration. Based on the applied chlorine dose, inactivation of E. coli by chlorine at neutral pH and room temperature was over two orders of magnitude less effective in ground water than in demand‐free water. Because of the high chlorine demand exerted by this ground water, chlorine residuals leaving the treatment plant are likely to be unstable.
Vadose Zone Characterization of Low‐Permeability Sediments Using Field Permeameters
Authors: Stephens Daniel B. , Unruh Mark , Havlena Jeff , Knowlton Robert G. , Mattson Earl , Cox Warren 
Published: February 2007

AbstractMeasurement of the saturated hydraulic conductivity of material in the unsaturated zone beneath proposed surface impoundments is important for predicting seepage rates of water and contaminants. Hazardous waste disposal facilities are commonly sited on the basis of the low permeability of the geologic materials beneath the site. Field measurement of the saturated hydraulic conductivity of low‐permeability materials may be accomplished using air‐entry permeameters and borehole permeameters. The results of a coordinated field and laboratory investigation of low‐permeability materials at a hazardous waste facility are presented. The different methods of testing and analysis are compared and discussed. In general, air‐entry permeameters and borehole permeameters are useful for measuring the saturated hydraulic conductivity of low‐permeability materials.
A Three‐Dimensional Analytical Model to Aid in Selecting Monitoring Locations in the Vadose Zone
Authors: McKee C. R. , Bumb A. C. 
Published: February 2007

AbstractMonitoring of the vadose zone is a potentially complex, time‐consuming, and expensive problem. The location of monitoring points and selection of monitoring instruments can be optimized by using computer models. Numerical models developed for this purpose in the past have often been expensive and difficult to use. This paper describes a fast, three‐dimensional, approximate analytical solution to the moisture content in the unsaturated zone. An analytical solution is available for steady‐state drainage, whereas an approximate analytical solution is available for the transient case. The model will handle an arbitrary distribution of fluid sources, as well as vertical and horizontal impermeable boundaries.The model may be applied to predict the incursion of fluid from accidental leakage or infiltration over large areas from unlined ponds and land treatment sites. The model is quite useful as an aid in designing monitoring or premonitoring programs near hazardous waste sites. Examples are presented to demonstrate the model's utility in estimating the maximum spread of a contaminant, the extent to which the fluid may spread with depth, the regions of high and low capillary pressure, and the non‐linear behavior of the saturation when drainage from several sources in considered. These results are useful for the placement of monitoring locations and the selection of appropriate instruments, and as a tool in working with regulatory agencies to design monitoring programs. A glimpse of the future is necessary for today's planning. Computer models are some of the most useful crystal balls we have available.
Use of Total Organic Carbon as an Indicator of Contamination from an Oil Refinery, South‐Central Kansas
Authors: Spruill Timothy B. 
Published: February 2007

AbstractWater samples collected from 26 sites at an abandoned oil refinery in south‐central Kansas were analyzed for total organic carbon (TOC) and specific volatile and semivolatile organic compounds by gas‐chromatography/mass‐spectrometric methods. Results from a Spearman‐rho correlation analysis between TOC concentration and the number of compounds (correlation coefficient = 0.71) and TOC concentration and total concentration of compounds identified (correlation coefficient = 0.83) indicate correlations significant at the 0.01 level.Although TOC data alone would not be sufficient to evaluate hazards posed by oil‐refinery wastes, results of the correlation analysis performed using data collected from the site in Kansas indicate that TOC data can be used effectively to delineate petroleum‐related ground water contamination and to help identify sources of ground water contaminants. TOC data collected from a large number of temporary sampling points during the initial phases of an investigation will provide an estimate of the extent of hydrocarbon contamination and allow placement of monitoring wells and more detailed sampling in appropriate areas.
An Inexpensive, Multi‐Use, Dedicated Pump for Ground Water Monitoring Wells
Authors: Ronnie E.H. , Nadon R.L. 
Published: February 2007

AbstractA simple, inexpensive sampling pump has lately come into use in ground water monitoring. The pump is referred to as an inertial pump; its only downhole components are a foot valve connected to a length of tubing or pipe. The operating principle of the pump is based on the inertia of a column of water within the riser tubing. Ground water is drawn through the foot valve and up the riser tubing by rapid up and down movements of the tubing. This pumping method is not new, but has only recently been applied to monitoring wells. Foot valves are available in a variety of materials and sizes and can be used in monitoring wells as small as 19mm (3/4 inch) I.D. Flexible polyethylene or Teflon® tubing, and in some cases stainless steel tubing or rigid PVC pipe, is used as the riser. The inertial pump satisfies most of the criteria normally cited for an “ideal” sampling device. The pump is easy to operate, reliable, durable, portable, and virtually maintenance‐free. It can be operated manually from as deep as 40m or from as deep as 60m using a motor drive. The pump is inexpensive, and therefore suitable for use as a dedicated sampling pump. Recent tests have shown the pump to be suitable for sampling volatile organics. The inertial pump has a high flow capacity and performs well in silty/sandy environments, which makes it useful for developing and purging monitoring wells. It may also be used to perform field hydraulic conductivity tests.