Download or read book In Situ Characterization of Dense Non Aqueous Phase Liquids Using Partitioning Tracers written by and published by . This book was released on 2000 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: Majors advances have been made during the past three years in our research on interwell partitioning tracers tests (PITTs). These advances include (1) progress on the inverse problem of how to estimate the three-dimensional distribution of NAPL in aquifers from the tracer data, (2) the first ever partitioning tracer experiments in dual porosity media, (3) the first modeling of partitioning tracers in dual porosity media (4) experiments with complex NAPLs such as coal tar, (5) the development of an accurate and simple method to predict partition coefficients using the equivalent alkane carbon number approach, (6) partitioning tracer experiments in large model aquifers with permeability layers, (7) the first ever analysis of partitioning tracer data to estimate the change in composition of a NAPL before and after remediation (8) the first ever analysis of partitioning tracer data after a field demonstration of surfactant foam to remediate NAPL and (9) experiments at elevated temperatures.
Download or read book In situ Characterization of Dense Non aqueous Phase Liquids UUsing Partitioning Tracers 1998 Annual Progress Report written by and published by . This book was released on 1998 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt: Major advances have been made during the past year in research on interwell partitioning tracers tests (PITTs). These advances include: (1) progress on the inverse problem of how to estimate the three-dimensional distribution of NAPL in aquifers from the tracer data, (2) the first ever partitioning tracer experiments in dual porosity media, (3) the first modeling of partitioning tracers in dual porosity media, (4) experiments with complex NAPLs such as coal tar, (5) the development of an accurate and simple method to predict partition coefficients using the equivalent alkane carbon number approach, (6) partitioning tracer experiments in large model aquifers with permeability layers, (7) the first ever analysis of partitioning tracer data to estimate the change in composition of a NAPL before and after remediation, (8) the first ever analysis of partitioning tracer data after a field demonstration of surfactant foam to remediate NAPL, and (9) experiments at elevated temperatures. The authors have developed a new analytic approach that has several advantages over existing approaches for inversion of tracer data. First, the technique utilizes an extremely efficient three-dimensional multiphase streamline simulator as a forward model. Second, the parameter sensitivities are formulated in terms of one-dimensional integrals of analytic functions along the streamlines. Thus, the computation of sensitivities for all model parameters requires only a single simulation run to construct the velocity field and generate the streamlines. The inversion of tracer data is then performed using a two-step iterative linearization that involves first lining-up the breakthrough times at the producing wells and then matching the production history. Their approach follows from an analogy between streamlines and ray tracing in seismology. The inverse method is analogous to seismic waveform inversion and thus, allows them to utilize efficient methods from geophysical imaging. The new approach has been applied for estimating permeability distribution based on conservative tracer tests (D.W. Vasco and A. Datta-Gupta: ''Asymptotic Solutions for Solute Transport: A Formalism for Tracer Tomography, '''' Submitted to Water Resources Research, December 1997), and is currently being extended for analysis of partitioning tracer data.
Download or read book Partitioning Tracers for In Situ Detection and Quantification of Dense Nonaqueous Phase Liquids in Groundwater Systems written by and published by . This book was released on 1999 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: The overall goal of the project is to explore the use of an innovative in-situ method (partitioning tracer tests) for detection and quantification of dense nonaqueous phase liquids (DNAPLs) in subsurface systems. DNAPLs occur in the subsurface at numerous contaminated sites and can act as long-term sources of groundwater contamination. Both effective risk assessment and remediation of DNAPL-contaminated sites is limited by current site characterization techniques. A major limitation of the current methods is that they provide data at discrete points, such that the probability of sampling a zone of localized DNAPL is quite small. The results of this research will lead to an improved method for characterizing DNAPL-contaminated sites and will enhance our understanding of the distribution of immiscible liquids in the subsurface. The use of this method will help reduce the uncertainty associated with risk assessments and remediation planning.
Download or read book Partitioning Tracers for in Situ Detection and Quantification of Dense Nonaqueous Phase Liquids in Groundwater Systems 1998 Annual Progress Report written by and published by . This book was released on 1998 with total page 3 pages. Available in PDF, EPUB and Kindle. Book excerpt: The overall goal of the proposed project is to explore the use of an innovative in-situ method for the detection and quantification of dense nonaqueous phase liquids (DNAPLs) in water-saturated and unsaturated heterogeneous media. Effective risk assessment and remediation of DNAPL contaminated sites is constrained by the limitations of current site characterization techniques. A major weakness of the current methods is that they provide data at discrete points, such that the probability of sampling a zone of localized DNAPL is quite small. The results of the proposed research will lead to improved techniques for characterizing DNAPL contaminated sites and will enhance the understanding of the distribution of DNAPLs in the subsurface. The use of this methods will reduce the uncertainty associated with risk assessments and remediation planning. The project objectives include exploring partitioning tracers for the detection and quantification of DNAPLs in saturated systems using aqueous tracers and in unsaturated systems using gas-phase tracers. This report summarizes work completed mid-way through year 2 of a 3-year project. Batch experiments have been conducted for a suite of bulk-phase partitioning tracers to determine water- trichloroethene (TCE) partitioning coefficients. Interfacial tension measurements have been made between TCE and solutions of several potential interface partitioning tracers. Preliminary column experiments have been conducted for the aqueous bulk-phase partitioning tracers using columns packed with a homogeneous sand and containing a residual saturation of TCE. These preliminary sets of experiments have enabled selection of suitable tracers for the water-saturated experiments and have lead to improved experimental designs and methods.
Download or read book An investigation of partitioning tracers for characterization of nonaqueous phase liquids in vadose zones written by George Allen Whitley and published by . This book was released on 1997 with total page 676 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Groundwater and Soil Cleanup written by National Research Council and published by National Academies Press. This book was released on 1999-11-21 with total page 301 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents a comprehensive, up-to-date review of technologies for cleaning up contaminants in groundwater and soil. It provides a special focus on three classes of contaminants that have proven very difficult to treat once released to the subsurface: metals, radionuclides, and dense nonaqueous-phase liquids such as chlorinated solvents. Groundwater and Soil Cleanup was commissioned by the Department of Energy (DOE) as part of its program to clean up contamination in the nuclear weapons production complex. In addition to a review of remediation technologies, the book describes new trends in regulation of contaminated sites and assesses DOE's program for developing new subsurface cleanup technologies.
Download or read book Partitioning Tracers for In Situ Measurement of Nonaqueous Phase Liquids in the Subsurface Final Report 09 written by and published by . This book was released on 2000 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: The overall goal of the proposed project is to explore the use of partitioning tracers to characterize dense nonaqueous phase liquids (DNAPLs) in aquifer systems. Bulk-phase partitioning tracers will be investigated to detect and determine DNAPL saturation, while interface partitioning tracers will be investigated to measure the area of the DNAPL-water interface. The specific objectives that will be addressed to accomplish this goal are: (1) Investigate the use of partitioning tracers to detect and determine both the saturation and interfacial area of DNAPLs in saturated porous media. (2) Investigate the effect of rate-limited mass transfer on the transport behavior of partitioning tracers. (3) Investigate the effect of porous-media heterogeneity on the transport behavior of partitioning tracers. (4) Develop and evaluate mathematical models capable of simulating the transport of partitioning tracers in complex systems. This proposal outlines an integrated approach for the development and testing of a unique method for detecting and measuring DNAPL in aquifer systems. The approach combines one-dimensional laboratory experiments, three-dimensional intermediate-scale flow cell experiments, physical methods for DNAPL description (including dual-energy gamma radiation), and advanced modeling techniques. This approach will allow a new, promising technique for characterizing DNAPL in aquifer systems to be verified by established laboratory and numerical methods. The effect of heterogeneity will be examined by the use of a flow-cell packed with layers of variable permeability and containing multiple sample ports. The effect of rate-limited liquid-liquid mass transfer will be investigated by examining the impact of pore-water velocity and DNAPL form on transport of the partitioning tracers. Effective risk assessment and remediation of DNAPL contaminated sites is constrained by the limitations of current site characterization techniques. A major weakness of the current methods is that they provide data at discrete points, such that the probability of sampling a zone of localized DNAPL is quite small. The results of the research will lead to improved techniques for characterizing DNAPL contaminated sites and will enhance our understanding of the distribution of DNAPLs in the subsurface risk assessments and remediation planning.
Download or read book Treating Dense Nonaqueous phase Liquids DNAPLs written by Godage B. Wickramanayake and published by . This book was released on 2000 with total page 272 pages. Available in PDF, EPUB and Kindle. Book excerpt: - DNAPL Site Characterization- DNAPL Modeling- DNAPL Remediation Technologies- DNAPLs in Fractured Media- Surfactant/Cosolvent Flushing.
Download or read book Practical Handbook of Environmental Site Characterization and Ground Water Monitoring written by David M. Nielsen and published by CRC Press. This book was released on 2005-09-28 with total page 1330 pages. Available in PDF, EPUB and Kindle. Book excerpt: Published in 1991, the first edition of The Practical Handbook of Ground-Water Monitoring quickly became the gold standard reference on the topic of ground-water monitoring. But, as in all rapidly evolving fields, regulations change, technology advances, methods improve, and research reveals flaws in prior thinking. As a consequence, books t
Download or read book Push Pull Tests for Site Characterization written by Jonathan David Istok and published by Springer Science & Business Media. This book was released on 2012-09-18 with total page 93 pages. Available in PDF, EPUB and Kindle. Book excerpt: The push-pull test is a powerful site characterization technique that has been applied to a wide range of problems in contaminant hydrogeology. The theoretical and practical apsects of push-pull testing were initially developed to characterize groundwater acquifers but the method has now been extended to saturated and unsaturated soils and sediments as well as to surface water bodies. Dr. Istok and his collaborators have been instrumental in the development of these techniques and he is widely recognized as the world's leading expert push-pull testing. This is the only reference book available on this powerful method.
Download or read book In Situ Remediation of Chlorinated Solvent Plumes written by Hans F. Stroo and published by Springer Science & Business Media. This book was released on 2010-09-10 with total page 807 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the late 1970s and early 1980s, our nation began to grapple with the legacy of past disposal practices for toxic chemicals. With the passage in 1980 of the Comprehensive Envir- mental Response, Compensation, and Liability Act (CERCLA), commonly known as Sup- fund, it became the law of the land to remediate these sites. The U. S. Department of Defense (DoD), the nation’s largest industrial organization, also recognized that it too had a legacy of contaminated sites. Historic operations at Army, Navy, Air Force, and Marine Corps facilities, ranges, manufacturing sites, shipyards, and depots had resulted in widespread contamination of soil, groundwater, and sediment. While Superfund began in 1980 to focus on remediation of heavily contaminated sites largely abandoned or neglected by the private sector, the DoD had already initiated its Installation Restoration Program in the mid-1970s. In 1984, the DoD began the Defense Environmental Restoration Program (DERP) for contaminated site assessment and remediation. Two years later, the U. S. Congress codified the DERP and directed the Secretary of Defense to carry out a concurrent program of research, development, and demonstration of innovative remediation technologies. As chronicled in the 1994 National Research Council report, “Ranking Hazardous-Waste Sites for Remedial Action,” our early estimates on the cost and suitability of existing techn- ogies for cleaning up contaminated sites were wildly optimistic. Original estimates, in 1980, projected an average Superfund cleanup cost of a mere $3.
Download or read book Partitioning Tracers for In situ Detection and Quantification of Dense Nonaqueous 1997 Annual Progress Report written by and published by . This book was released on 1997 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: The overall goal of the proposed project is to explore the use of partitioning tracers to characterize dense nonaqueous phase liquids (DNAPLs) in subsurface systems. Bulk-phase partitioning tracers will be investigated to detect and determine DNAPL saturation, while interface partitioning tracers will be investigated to measure the area of the DNAPL-water interface. The specific objectives that will be addressed to accomplish this goal are: (1) investigate the use of partitioning tracers to detect and determine both the saturation and interfacial area of DNAPLs in saturated porous media; (2) investigate the effect of rate-limited mass transfer on the transport behavior of partitioning tracers; (3) investigate the effect of porous-media heterogeneity on the transport behavior of partitioning tracers; and (4) develop and evaluate mathematical models capable of simulating the transport of partitioning tracers in complex systems.
Download or read book Characterization of Complex Non aqueous Phase Liquids NAPLs in the Subsurface Environment written by Matthias Piepenbrink and published by . This book was released on 2007 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Tracer Techniques for DNAPL Source Delineation and In Situ Flushing Techniques for Enhanced Source Removal Pilot Scale Demonstrations at the Dover National Test Site written by and published by . This book was released on 2001 with total page 293 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this study was to evaluate the performance of innovative tracer techniques for dense nonaqueous phase liquid (DNAPL) characterization and in-situ cosolvent and surfactant flushing for DNAPL removal in an isolated test cell (3.0m x 4.5m x 1 2.3m) located at the Dover National Test Site, Dover AFB, DE. As part of a larger project to assess the performance of several in-situ flushing technologies for DNAPL source removal, it involved controlled releases of up to 100L of perchloroethylene (POE) into test cells for each remedial technology. Subsequent to POE release, two partitioning tracer tests were conducted: one before and another after the remedial test. The University of Florida (UF) conducted the first remedial demonstration, cosolvent flushing, and the second remedial demonstration, surfactant flushing, was conducted jointly by UF and the University of Oklahoma (UO). The focus of this report is the four partitioning tracer tests and the cosolvent flushing demonstration.
Download or read book Delivery and Mixing in the Subsurface written by Peter K. Kitanidis and published by Springer Science & Business Media. This book was released on 2012-04-23 with total page 351 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume is meant to provide the practitioner with information on the natural mixing processes occurring in aquifers as well as to describe basic strategies that can be implemented to enhance mixing in particular cases. For example, when it comes to mixing miscible liquids, one can speed up mixing in the formation by manipulating the flow such as through the use of recirculation wells. Furthermore, much of the mixing can be achieved partially within recirculation wells themselves, where contaminated water is admixed with additives, volatile products may be removed through a vapor mass exchanger, etc. Thus, adding mixing wells can significantly increase the performance of the delivery and mixing system and speed up the process of remediation.
Download or read book Groundwater Quality written by Karel Kovar and published by IAHS Press. This book was released on 1998 with total page 622 pages. Available in PDF, EPUB and Kindle. Book excerpt:
