Download or read book Transport of Dissolved Volatile Organic Compounds in the Unsaturated Zone written by Munjed A. Maraqa and published by . This book was released on 1995 with total page 340 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Mass Transport of Volatile Organic Compounds Between the Saturated and Vadose Zones written by Monte S. Harner and published by . This book was released on 1996-12-01 with total page 99 pages. Available in PDF, EPUB and Kindle. Book excerpt: Volatile organic compounds (VOCs) dissolved in the saturated zone are transported into the vadose zone primarily by gaseous phase diffusion. If the saturated zone is remediated, VOCs present in the vadose zone may become a secondary source of contamination for the groundwater The amount of VOCs that remain in the vadose zone is dependent on site hydrology, soil properties, and the chemical properties of the contaminants. The purpose of this study was to determine what conditions caused VOC concentrations in the vadose zone to significantly recontaminate the saturated zone. A one-dimensional numerical model was developed to investigate the transport of a VOC, trichioroethylene, between the saturated and vadose zones under a variety of conditions. The model featured steady-state unsaturated water flow and transient contaminant transport Transport mechanisms included aqueous phase advection-dispersion and gaseous phase diffusion. Partitioning between the water, gas, and soil compartments were modeled as equilibrium processes. Sensitivity analyses were performed on several variables including soil type (homogeneous and heterogeneous profiles), water infiltration rate and vadose zone depth. Results indicated that recontamination was most significant rate, and vadose zone depth. Results indicated that recontamination was most significant in the presence of heterogeneous soils, low infiltration rates and deep vadose zones.

Download or read book A review of transport and attenuation of dissolved phase volatile organic compounds VOCs in the unsaturated zone written by G.P. Wealthall and published by . This book was released on 2010 with total page 91 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Transport and Biodegradation of Volatile Organic Compounds written by Sara Picone and published by . This book was released on 2012 with total page 149 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Numerical Solution to Three dimensional Multiphase Transport of Volatile Organic Compounds in Unsaturated Soils with an Application to the Remedial Method of In situ Volatilization Part I written by and published by . This book was released on 1992 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt: Part I of this paper presents the development and application of a numerical model for determining the fate and transport of volatile organic compounds (VOCS) in the unsaturated zone resulting from forced volatilization and gaseous advection-dispersion of organic vapor in a multipartitioned three-dimensional environment. The model allows for single-component transport in the gas and water phases. The hydrocarbon is assumed to be in specific retention and, therefore, immobile. Partitioning of the hydrocarbon between the oil, water, gas, and soil is developed as rate-limited functions that are incorporated into sink/source terms in the transport equations. The code for the model was developed specifically to investigate in-situ volatilization (ISV) remedial strategies, predict the extent of cleanup from information obtained at a limited number of measurement locations, and to help design ISV remedial systems. Application of the model is demonstrated for a hypothetical one-dimensional ISV system. Part II of this paper will present the analysis of an existing ISV system using the full three-dimensional capability of the model.

Download or read book Coupling Transport and Biodegradation of Volatile Organic Compounds in Unsaturated Soils written by Yassar Hamad El-Farhan and published by . This book was released on 1997 with total page 416 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Coupled Processes Diffusive Transport and Biodegradation of Volatile Organic Compounds in Unsaturated Porous Media written by and published by . This book was released on 1998 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: Diffusive transport of volatile organic compounds (VOCs) and their degradation by bacteria in unsaturated soils are coupled by poorly understood mass transfer kinetics at the gas/water interface. The capability to predict the fate of VOCs in m saturated soil is necessary to evaluate the feasibility of natural attenuation as a VOC remediation strategy. The objective of this study was to develop a mechanistically based mathematical model that considered the interdependence of VOC diffusive transport, mass transfer at the gas/water interface, microbial activity, and sorptive interactions in a moist, unsaturated soil. Because the focus of the model was on description of natural attenuation, the advective VOC transport that is induced in engineered remediation processes such as vapor extraction was not considered. The utility of the model was assessed through its ability to describe experimental observations from well-defined experiments in which toluene was used as a representative VOC and diffused through soil columns that contained a toluene degrading bacterium, Pseudomonasputida. The coefficient for gas-liquid mass-transfer, KLa, was found to be a key parameter controlling the ability of bacteria to degrade VOCs. This finding indicates that soil size and geometry are likely to be dominant parameters in assessing the possible success of natural attenuation of VOCs in contaminated unsaturated soils.

Download or read book Soil Vapor Extraction SVE Enhancement Technology Resource Guide written by and published by . This book was released on 1995 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Physicochemical Groundwater Remediation written by James A. Smith and published by Springer Science & Business Media. This book was released on 2001-07-31 with total page 368 pages. Available in PDF, EPUB and Kindle. Book excerpt: You will learn how palladium catalyzes the dehalogenation of chlorinated solvents.

Download or read book Contaminants in the Subsurface written by National Research Council and published by National Academies Press. This book was released on 2005-04-23 with total page 371 pages. Available in PDF, EPUB and Kindle. Book excerpt: At hundreds of thousands of commercial, industrial, and military sites across the country, subsurface materials including groundwater are contaminated with chemical waste. The last decade has seen growing interest in using aggressive source remediation technologies to remove contaminants from the subsurface, but there is limited understanding of (1) the effectiveness of these technologies and (2) the overall effect of mass removal on groundwater quality. This report reviews the suite of technologies available for source remediation and their ability to reach a variety of cleanup goals, from meeting regulatory standards for groundwater to reducing costs. The report proposes elements of a protocol for accomplishing source remediation that should enable project managers to decide whether and how to pursue source remediation at their sites.

Download or read book A Numerical Solution to Three dimensional Multiphase Transport of Volatile Organic Compounds in Unsaturated Soils with Application to the Remedial Method of In situ Volatilization written by and published by . This book was released on 1992 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book U S Geological Survey Toxic Substances Hydrology Program written by U.S. Geological Survey Toxic Substances Hydrology Program. Technical Meeting and published by . This book was released on 1996 with total page 642 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book U S Geological Survey Open file Report written by and published by . This book was released on 1996 with total page 622 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Site Characterization for Subsurface Remediation written by and published by . This book was released on 1991 with total page 276 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Water resources Investigations Report written by and published by . This book was released on 1999 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Subsurface Restoration written by C. H. Ward and published by CRC Press. This book was released on 1997-11-01 with total page 704 pages. Available in PDF, EPUB and Kindle. Book excerpt: Presenting a clear, understandable examination, this book outlines efficient, effective methods and strategies for the complex field of subsurface remediation. The editors fully assess the state-of-knowledge of subsurface science requisite for finding new solutions, providing a focused guide for advanced subsurface remediation technology. Unparalleled in scope and practicality, Subsurface Restoration assists those persons determining the extent of environmental contamination for remedial technology selection and for environmental decision-making at all levels.

Download or read book U S Geological Survey Toxic Substances Hydrology Program written by Gail E. Mallard and published by . This book was released on 1992 with total page 748 pages. Available in PDF, EPUB and Kindle. Book excerpt: