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Geology and Ground-Water Resources of Camden County, New Jersey

Description: From introduction: The purpose of this investigation is to collect and interpret the basic hydrologic and geologic data and to appraise and report on the ground-water resources of Camden County. The objectives were to define the thickness and areal extent of the hydrologic units, evaluate the hydraulic characteristics of the aquifers, determine the effect of pumpage on the water levels of the area, define the source of recharge of the aquifers, and to evaluate the chemical quality of the ground water.
Date: June 1976
Creator: Farlekas, George M.; Nemickas, Bronius & Gill, Harold E.
Partner: UNT Libraries Government Documents Department

Ground-Water Contamination at Wurtsmith Air Force Base, Michigan

Description: From introduction: The U.S. Geological Survey, at the request of the U.S. Air Force, began an investigation of geologic and hydrologic conditions at Wurtsmith Air Force Base in September 1979. The investigation was prompted by the discovery that an underground storage tank containing trichloroethylene (TCE) had leaked, contaminating Base water-supply wells. Subsequent information suggested that the trichloroethylene had moved off-Base.
Date: 1983
Creator: Stark, J. R.; Cummings, T. R. & Twenter, F. R.
Partner: UNT Libraries Government Documents Department

Hydrogeology of the Buffalo Aquifer, Clay and Wilkin Counties, West-Central Minnesota

Description: From introduction: The objective of this study are to (1) determine the areal extent and thickness of the Buffalo aquifer and the general occurrence of deeply buried aquifers, (2) determine the potential for development of water supplies from wells in the Buffalo aquifer, (3) investigate and discuss annual recharge to the Buffalo aquifer and the potential for artificially recharging the aquifer, (4) determine the chemical quality of water in the aquifer and in area streams, (5) establish a network of observation wells for monitoring water levels and water quality in the aquifer, (6) determine the relationship between the aquifer and the adjacent streams, and (7) update the information on the flow characteristics of the streams. The main focus of this study is on water in the Buffalo aquifer and on flow characteristics of streams.
Date: February 1981
Creator: Wolf, Ronald J.
Partner: UNT Libraries Government Documents Department

A Conductivity Relationship for Steady-state Unsaturated Flow Processes under Optimal Flow Conditions

Description: Optimality principles have been used for investigating physical processes in different areas. This work attempts to apply an optimal principle (that water flow resistance is minimized on global scale) to steady-state unsaturated flow processes. Based on the calculus of variations, we show that under optimal conditions, hydraulic conductivity for steady-state unsaturated flow is proportional to a power function of the magnitude of water flux. This relationship is consistent with an intuitive expectation that for an optimal water flow system, locations where relatively large water fluxes occur should correspond to relatively small resistance (or large conductance). Similar results were also obtained for hydraulic structures in river basins and tree leaves, as reported in other studies. Consistence of this theoretical result with observed fingering-flow behavior in unsaturated soils and an existing model is also demonstrated.
Date: September 15, 2010
Creator: Liu, H. H.
Partner: UNT Libraries Government Documents Department

Mathematical and geological approaches to minimizing the data requirements for statistical analysis of hydraulic conductivity distribution. Annual report

Description: The following research was completed: refinement of air-pereameter design, calibration; collection of air-flow-rate data at the facies scale; mapping of depositional facies at an outcrop west of Belen, New Mexico; delineation of permeability facies from mapped depositional facies and geostatitistical analysis of air-flow-rate data observed at the facies scale (Sierra Ladrones formation); and evaluation of threshold-crossing theory.
Date: August 1, 1990
Creator: Phillips, F.M. & Wilson, J.L.
Partner: UNT Libraries Government Documents Department

Visualization of micro-scale phase displacement processes in retention and outflow experiments: Non-uniqueness of unsaturated flow properties

Description: Methods to determine unsaturated hydraulic properties can exhibit random and non-unique behavior. The authors assess the causes for these behaviors by visualizing micro-scale phase displacement processes during equilibrium retention and transient outflow experiments. They observe that the drainage process is composed of a fast fingering followed by a slower backfilling. The influence of each these processes is controlled by the size and the speed of the applied boundary step, the initial saturation and its structure and by small-scale heterogeneities. Because the mixture of these micro-scale processes yields macro-scale effective behavior, measured unsaturated flow properties are also a function of these controls. These results suggest limitations on the current definitions and uniqueness of unsaturated hydraulic properties.
Date: March 9, 2000
Partner: UNT Libraries Government Documents Department

A Self-Consistent Approach for Calculating the Effective Hydraulic Conductivity of a Bimodal, Heterogeneous Medium

Description: In this paper, we consider an approach for estimating the effective hydraulic conductivity of a 3D medium with a binary distribution of local hydraulic conductivities. The medium heterogeneity is represented by a combination of matrix medium conductivity with spatially distributed sets of inclusions. Estimation of effective conductivity is based on a self-consistent approach introduced by Shvidler (1985). The tensor of effective hydraulic conductivity is calculated numerically by using a simple system of equations for the main diagonal elements. Verification of the method is done by comparison with theoretical results for special cases and numerical results of Desbarats (1987) and our own numerical modeling. The method was applied to estimating the effective hydraulic conductivity of a 2D and 3D fractured porous medium. The medium heterogeneity is represented by a combination of matrix conductivity and a spatially distributed set of highly conductive fractures. The tensor of effective hydraulic conductivity is calculated for parallel- and random-oriented sets of fractures. The obtained effective conductivity values coincide with Romm's (1966) and Snow's (1969) theories for infinite fracture length. These values are also physically acceptable for the sparsely-fractured-medium case with low fracture spatial density and finite fracture length. Verification of the effective hydraulic conductivity obtained for a fractured porous medium is done by comparison with our own numerical modeling for a 3D case and with Malkovsky and Pek's (1995) results for a 2D case.
Date: January 2, 2004
Creator: Pozdniakov, Sergey & Tsang, Chin-Fu
Partner: UNT Libraries Government Documents Department

Flow channeling and analysis of tracer tests in heterogeneous porous media

Description: Flow and solute transport through porous medium with strongly varying hydraulic conductivity are studied by numerical simulations. The heterogeneity of the porous medium is defined by {sigma} and {lambda}{prime}, which are, respectively, the standard deviation of natural log of permeability values and its correlation range {lambda} divided by transport distance L. The development of flow channeling as a function of these two parameters is demonstrated. The results show that for large heterogeneities, the flow is highly channelized and solute is transported through a few fast paths, and the corresponding breakthrough curves show a high peak at very early times, much shorter than the mean residence time. This effect was studied for a converging radial flow, to simulate tracer tests in a fracture zone or contact-thickness aquifer. It is shown that {sigma}{sup 2}{lambda}{prime} is an appropriate parameter to characterize the tracer dispersion and breakthrough curves. These results are used to study tracer breakthrough data from field experiments performed with nonsorbing tracers. A new procedure is proposed to analyze the results. From the moments of the residence-time distribution represented by the breakthrough curves, the heterogeneity of the porous medium, as characterized by {sigma}{sup 2}{lambda}{prime} and the mean residence time t{sub o}, may be determined.
Date: November 3, 2001
Creator: Moreno, Luis & Tsang, Chin-Fu
Partner: UNT Libraries Government Documents Department


Description: The proposed Saltstone Disposal Unit 6 (SDU6) is a larger structure than the SDU4 cells and larger than the disposal units (SDU2, SDU3, and SDU5) currently in use or under construction. The additional capacity provided by SDU6 is desired to reduce life cycle costs and support site accelerated closure goals. The larger size of the planned SDU6 could result in saltstone being placed in thinner lifts as the unit is filled. This study was performed to determine whether thinner layers of saltstone negatively impact the performance of the waste form. A larger number of cold joints could potentially result in increased drying, salt deposition, and surface oxidation. A matrix of samples was prepared to simulate thin pours ranging from 0.5 to 6 inches thick. Each sample was cured for at least 28 days prior to further characterization. Leachability results showed that there is no obvious impact of the number of grout layers on the Leachability Index values for Na and NO{sub 3}. The concentrations of Cr, NO{sub 2}, and C{sub 2}O{sub 4} were below detection limits for all of the leachates. No attempt was made to evaluate the oxidation of these samples since no measureable Cr was leached, although this would appear to indicate that Cr in the samples remained reduced for cold joints with surfaces exposed for approximately four days. The results of hydraulic conductivity measurements showed that the number of cold joints in the samples did not have a significant impact on the measured values for the vertical lift orientation (i.e., when the flow path is perpendicular to the cold joints). For the horizontal lift orientation (i.e., when the flow path is parallel to the cold joints), the number of cold joints in the samples also did not appear to have a significant impact on hydraulic conductivity. The ...
Date: October 2, 2012
Creator: Cozzi, A.; Langton, C. & Fox, K.
Partner: UNT Libraries Government Documents Department

Hydraulic Property and Soil Textural Classification Measurements for Rainier Mesa, Nevada Test Site, Nevada

Description: This report presents particle size analysis, field-saturated hydraulic conductivity measurements, and qualitative descriptions of surficial materials at selected locations at Rainier Mesa, Nevada. Measurements and sample collection were conducted in the Rainier Mesa area, including unconsolidated sediments on top of the mesa, an ephemeral wash channel near the mesa edge, and dry U12n tunnel pond sediments below the mesa. Particle size analysis used a combination of sieving and optical diffraction techniques. Field-saturated hydraulic conductivity measurements employed a single-ring infiltrometer with analytical formulas that correct for falling head and spreading outside the ring domain. These measurements may prove useful to current and future efforts at Rainier Mesa aimed at understanding infiltration and its effect on water fluxes and radionuclide transport in the unsaturated zone.
Date: December 29, 2009
Creator: Ebel, Brian A. & Nimmo, John R.
Partner: UNT Libraries Government Documents Department

Geologic Controls of Hydraulic Conductivity in the Snake River Plain Aquifer At and Near the Idaho National Engineering and Environmental Laboratory, Idaho

Description: The effective hydraulic conductivity of basalt and interbedded sediment that compose the Snake River Plain aquifer at and near the Idaho National Engineering and Environmental Laboratory (INEEL) ranges from about 1.0x10 -2 to 3.2x10 4 feet per day (ft/d). This six-order-of-magnitude range of hydraulic conductivity was estimated from single-well aquifer tests in 114 wells, and is attributed mainly to the physical characteristics and distribution of basalt flows and dikes. Hydraulic conductivity is greatest in thin pahoehoe flows and near-vent volcanic deposits. Hydraulic conductivity is least in flows and deposits cut by dikes. Estimates of hydraulic conductivity at and near the INEEL are similar to those measured in similar volcanic settings in Hawaii. The largest variety of rock types and the greatest range of hydraulic conductivity are in volcanic rift zones, which are characterized by numerous aligned volcanic vents and fissures related to underlying dikes. Three broad categories of hydraulic conductivity corresponding to six general types of geologic controls can be inferred from the distribution of wells and vent corridors. Hydraulic conductivity of basalt flows probably is increased by localized fissures and coarse mixtures of interbedded sediment, scoria, and basalt rubble. Hydraulic conductivity of basalt flows is decreased locally by abundant alteration minerals of probable hydrothermal origin. Hydraulic conductivity varies as much as six orders of magnitude in a single vent corridor and varies from three to five orders of magnitude within distances of 500 to 1,000 feet. Abrupt changes in hydraulic conductivity over short distances suggest the presence of preferential pathways and local barriers that may greatly affect the movement of ground water and the dispersion of radioactive and chemical wastes downgradient from points of waste disposal.
Date: February 1, 1999
Creator: Anderson, S. R.; Kuntz, M. A. & Davis, L. C.
Partner: UNT Libraries Government Documents Department

Inversion of Hydrological Tracer Test Data Using TomogrpahicConstraints

Description: A reasonable description of the hydraulic conductivity structure is a prerequisite for modeling contaminant transport. However, formulations of hydrogeological inverse problems utilizing hydrogeological data only often fail to reliably resolve features at a resolution required for accurately predicting transport. Incorporation of geophysical data into the inverse problem offers the potential to increase this resolution. In this study, we invert hydrological tracer test data using the shape and relative magnitude variations derived from geophysical tomographic data to regionalize a hydrogeological inverse problem in order to estimate the hydraulic conductivity structure. Our approach does not require that the petrophysical relationship be known a-priori, but that it is linear and stationary within each geophysical anomaly. However, tomograms are imperfect models of geophysical properties and geophysical properties are not necessarily strongly linked to hydraulic conductivity. Therefore, we focus on synthetic examples where the correlation between radar velocity and hydraulic conductivity, as well as the geophysical data acquisition errors, are varied in order to assess what aspects of the hydraulic conductivity structure we can expect to resolve under different conditions. The results indicate that regularization of the tracer inversion procedure using geophysical data improves estimates of hydraulic conductivity. We find that even under conditions of corrupted geophysical data, we can accurately estimate the effective hydraulic conductivity and areas of high and low hydraulic conductivity. However, given imperfect geophysical data, our results suggest that we cannot expect accurate estimates of the variability of the hydraulic conductivity structure.
Date: November 11, 2004
Creator: Linde, Niklas; Finsterle, Stefan & Hubbard, Susan
Partner: UNT Libraries Government Documents Department

Heat as a Tracer to Examine Hydraulic Conductance Near the RussianRiver Bank Filtration Facility, Sonoma County, CA

Description: Both the measurement of temperature and the simulation of heat and water transport have benefited from significant recent advances in data acquisition and computer resources. This has afforded the opportunity for routine use of heat as a tracer in a variety of hydrological regimes. Heat is particularly well suited for investigations of stream/groundwater exchanges. Dynamic temperature patterns between the stream and underlying sediments are typical, due to large stream surface area to volume ratios relative to other surface water bodies. Heat is a naturally occurring tracer, free from (real or perceived) issues of contamination associated with use of chemical tracers in stream environments. The use of heat as a tracer relies on the measurement of temperature gradients, and temperature is an extremely robust parameter to monitor. Temperature data is immediately available as opposed to chemical tracers, which often require significant laboratory analysis. In this work, we report on the progress in the use of heat as a tracer to determine the hydraulic conductance of the streambed along the middle reaches of the Russian River, located west of Santa Rosa, CA. The general hydrological setting is described and the unique matter in which the water resources are managed in an environment of increasing population, a rapid shift to agricultural crops requiring more irrigation, and a series of fishery related mandates.
Date: August 1, 2004
Creator: Constantz, Jim; Su, Grace & Hatch, Christine
Partner: UNT Libraries Government Documents Department


Description: The FRACSL flow and transport code is under development as part of an effort to improve reservoir characterization techniques. The present version simulates a two-dimensional, isothermal reservoir composed of a global fracture network imbedded in a porous media. FRACSL simulates the hydraulic response of a reservoir to injection or backflow. The code simulates the movement of injected tracers within the reservoir by adding advective and random dispersive motions of discrete particles. FRACSL has been benchmarked against theoretical flow and transport responses in simple systems. It has been used to simulate a benchscale physical model and to correlate flow and dispersion data from the East Mesa Hydrothermal Injection Test Program. Correlation of East Mesa data has provided an estimate of an anisotropic hydraulic conductivity, a natural drift in the reservoir, and dispersivity.
Date: January 22, 1985
Creator: Clemo, T.M.
Partner: UNT Libraries Government Documents Department

Water Imbibition into Rock as Affected by Sample Shape, Pore, Conductivity, and Antecedent Water Content

Description: Infiltration is often presumed to follow Philip's equation, I = st{sup 1/2}, where I is cumulative infiltration, s is sorptivity, and t is time. This form of the equation is appropriate for short times, and/or for negligible gravitational effects. For a uniform soil, this equation describes a plot of log(mass imbibed) versus log(time), with a slope (imbibition exponent) of 1/2. The equation has also been applied to low-porosity rocks, where the extremely small pores render gravitational forces negligible. Experiments recently performed on a wide variety of rocks produced imbibition exponents from 0.2 to 0.5. Many rock types showed initial imbibition proceeding as I {approx} t{sup 1/4}, then later switched to ''normal'' (t{sup 1/2}) behavior. The distance to the wetting front that corresponds to this cross-over behavior was found to be related to the sample shape: tall thin samples are more likely to exhibit the exponent 1/4, and to cross over to 1/2-type behavior later, while short, squat samples are less likely to display the 1/4-type behavior at all. Additionally, the exponents are sensitive to antecedent water content, with initially wetter samples having smaller values. In this study, we present the experimental data, and provide a consistent and physically-based explanation using percolation theory. The analogy between imbibition and diffusion is used to model imbibition into samples with low pore connectivity, with the exponents and their crossover behavior emerging from a random walk process. All laboratory phenomena--different exponents, crossover behavior, and effects of sample shape and antecedent water content--are reproduced by the model, with similar patterns across experiment and simulation. We conclude both that diffusion is a useful and powerful conceptual model for understanding imbibition, and also that imbibition experiments, being simpler than diffusion measurements, can be used to examine diffusive behavior in rock.
Date: August 29, 2005
Creator: Ewing, R.P.
Partner: UNT Libraries Government Documents Department

Formed Core Sampler Hydraulic Conductivity Testing

Description: A full-scale formed core sampler was designed and functionally tested for use in the Saltstone Disposal Facility (SDF). Savannah River National Laboratory (SRNL) was requested to compare properties of the formed core samples and core drilled samples taken from adjacent areas in the full-scale sampler. While several physical properties were evaluated, the primary property of interest was hydraulic conductivity. Differences in hydraulic conductivity between the samples from the formed core sampler and those representing the bulk material were noted with respect to the initial handling and storage of the samples. Due to testing conditions, the site port samples were exposed to uncontrolled temperature and humidity conditions prior to testing whereas the formed core samples were kept in sealed containers with minimal exposure to an uncontrolled environment prior to testing. Based on the results of the testing, no significant differences in porosity or density were found between the formed core samples and those representing the bulk material in the test stand.
Date: September 25, 2012
Creator: Miller, D. H. & Reigel, M. M.
Partner: UNT Libraries Government Documents Department

Characterization of Coupled Hydrologic-Biogeochemical Processes Using Geophysical Data

Description: Biogeochemical and hydrological processes are naturally coupled and variable over a wide range of spatial and temporal scales. Many remediation approaches also induce dynamic transformations in natural systems, such as the generation of gases, precipitates and biofilms. These dynamic transformations are often coupled and can reduce the hydraulic conductivity of the geologic materials, making it difficult to introduce amendments or to perform targeted remediation. Because it is difficult to predict these transformations, our ability to develop effective and sustainable remediation conditions at contaminated sites is often limited. Further complicating the problem is the inability to collect the necessary measurements at a high enough spatial resolution yet over a large enough volume for understanding field-scale transformations.
Date: June 1, 2005
Creator: Hubbard, Susan
Partner: UNT Libraries Government Documents Department

In situ clay formation : evaluation of a proposed new technology for stable containment barriers.

Description: Containment of chemical wastes in near-surface and repository environments is accomplished by designing engineered barriers to fluid flow. Containment barrier technologies such as clay liners, soil/bentonite slurry walls, soil/plastic walls, artificially grouted sediments and soils, and colloidal gelling materials are intended to stop fluid transport and prevent plume migration. However, despite their effectiveness in the short-term, all of these barriers exhibit geochemical or geomechanical instability over the long-term resulting in degradation of the barrier and its ability to contain waste. No technologically practical or economically affordable technologies or methods exist at present for accomplishing total remediation, contaminant removal, or destruction-degradation in situ. A new type of containment barrier with a potentially broad range of environmental stability and longevity could result in significant cost-savings. This report documents a research program designed to establish the viability of a proposed new type of containment barrier derived from in situ precipitation of clays in the pore space of contaminated soils or sediments. The concept builds upon technologies that exist for colloidal or gel stabilization. Clays have the advantages of being geologically compatible with the near-surface environment and naturally sorptive for a range of contaminants, and further, the precipitation of clays could result in reduced permeability and hydraulic conductivity, and increased mechanical stability through cementation of soil particles. While limited success was achieved under certain controlled laboratory conditions, the results did not warrant continuation to the field stage for multiple reasons, and the research program was thus concluded with Phase 2.
Date: March 1, 2004
Creator: Nagy, Kathryn L. (University of Illinois at Chicago, Chicago, IL); DiGiovanni, Anthony Albert & Fredrich, Joanne T.
Partner: UNT Libraries Government Documents Department

BP-5 Remedial Investigation Slug-Test Characterization Results for Well 699-52-55A

Description: Pacific Northwest National Laboratory conducted slug-test characterization at the final, completed BP-5 Remedial Investigation well 699-52-55A near the 200-East Area at the Hanford Site on April 22, 2008. The slug-test characterization was in support of the BP-5 Remedial Investigation. The portion of the unconfined aquifer tested is composed of sediments of the lower Ringold Formation and the underlying Elephant Mountain basalt flowtop. The basalt flowtop unit was included as part of the effective test-interval length for the slug-test analysis because the flowtop unit is hydraulically communicative with the unconfined aquifer. Estimates of hydraulic conductivity for the effective test-interval length represent composite values for the lower Ringold Formation and the underlying Elephant Mountain basalt flow top.
Date: July 21, 2008
Creator: Newcomer, Darrell R.
Partner: UNT Libraries Government Documents Department

Quantifying the effects of three-dimensional subsurface heterogeneity on Hortonian runoff processes using a fully-coupled numerical, stochastic approach.

Description: The impact of three-dimensional subsurface heterogeneity on hillslope runoff generated by excess infiltration (so called Hortonian runoff) is examined. A fully-coupled, parallel subsurface overland flow model is used to simulate runoff from an idealized hillslope. Ensembles of correlated, Gaussian random fields of saturated hydraulic conductivity are used to create uncertainty and variability (i.e. structure) due to subsurface heterogeneity. A large number of cases are simulated in a parametric manner with variance of the hydraulic conductivity varied over two orders of magnitude. These cases include rainfall rates above, equal and below the geometric mean of the hydraulic conductivity distribution. These cases are also compared to theoretical considerations of runoff production based on simple assumptions regarding (1) the rainfall rate and the value of hydraulic conductivity in the surface cell using a spatially-indiscriminant approach; and (2) a percolation-theory type approach to incorporate so-called runon. Simulations to test the ergodicity of hydraulic conductivity on hillslope runoff are also performed. Results show three-dimensional features (particularly in the vertical dimension) in the hydraulic conductivity distributions that create shallow perching, which has an important effect on runoff behavior that is fundamentally different in character than previous two dimensional analyses. The simple theories are shown to be very poor predictors of the saturated area that might runoff due to excess infiltration. It is also shown that ergodicity is reached only for a large number of integral scales ({approx}30) and not for cases where the rainfall rate is less than the geometric mean of the saturated hydraulic conductivity.
Date: August 23, 2007
Creator: Maxwell, R M & Kollet, S J
Partner: UNT Libraries Government Documents Department


Description: We present an analysis of the slug test in a well surrounded by an annulus of altered material, which is treated as a skin of finite thickness. By assuming the skin has a thickness, the storage capacity of the altered material is included in the analysis. The problem is solved in the Laplace domain. The solution is found in terms of well-bore storage and the thickness, hydraulic conductivity, and specific storage of the skin. Type curves are generated by numerical inversion of the Laplace transform solution. We find that standard methods of analysis, involving a skin of infinitesimal thickness, are adequate for open-well or drill-stem tests. However, for pressurized tests the response may differ markedly from standard slug-test solutions.
Date: January 22, 1985
Creator: Moench, A.F. & Hsieh
Partner: UNT Libraries Government Documents Department

Slug Test Characterization Results for Multi-Test/Depth Intervals Conducted During the Drilling of CERCLA Operable Unit OU ZP-1 Wells 299-W10-33 and 299-W11-48

Description: Slug-test results obtained from single and multiple, stress-level slug tests conducted during drilling and borehole advancement provide detailed hydraulic conductivity information at two Hanford Site Operable Unit (OU) ZP-1 test well locations. The individual test/depth intervals were generally sited to provide hydraulic-property information within the upper ~10 m of the unconfined aquifer (i.e., Ringold Formation, Unit 5). These characterization results complement previous and ongoing drill-and-test characterization programs at surrounding 200-West and -East Area locations (see Figure S.1).
Date: September 30, 2007
Creator: Newcomer, Darrell R.
Partner: UNT Libraries Government Documents Department