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Informationen zum Autor Alex S. Mayer is a Charles and Patricia Nelson Presidential Professor, Civil and Environmental Engineering, Michigan Technological University. Klappentext Published by the American Geophysical Union as part of the Water Resources Monograph Series, Volume 17. Nonaqueous phase liquids (NAPLs) are frequently found as soil and groundwater contaminants. Highly toxic even in small volumes, NAPLs can pose a threat to human health and damage surface and subsurface ecosystems. In this book, we clarify the complex phenomena of NAPL migration and offer insight into the behavior of NAPLs at sites undergoing monitoring and remediation. Contents include discussion on: Principles of NAPL behavior in the subsurface, including flow, transfer of components to water and gas phases, and transport Migration and distribution Site characterization and monitoring Remediation methods, including hydraulic removal, pump and treat, and soil vapor extraction Further discussion on gaps in our understanding of NAPLs at the field scale along with a thorough tutorial approach and supplemental CD, make this book an important guide and resource for practicing engineers and scientists, risk assessment professionals, teachers, and students. Inhaltsverzeichnis Preface v 1 Introduction A. S. Mayer and S. M. Hassanizadeh 1 2 Fundamentals K. H. Jensen and R. W. Falta 5 2.1 NAPL Characteristics and behavior of NAPLs in the subsurface 5 2.2 Parametersr esponsiblefo r NAPL distributiona nd flow in the subsurface 9 2.2.1 Interfacial tension and wettability 9 2.2.2 Capillary p ressure a nd capillary p ressure c urves 12 2.2.3 Relative permeability and relative permeability curves 24 2.2.4 Darcy's law and governinge quations for multiphase flow 27 2.3 NAPL mass transfer and transport 30 2.3.1 VaporP ressurea nd Solubility 31 2.3.2 Phase Densities 32 2.3.3 Concentrations 34 2.3.4 Equilibrium Phase Partitioning 37 2.3.5 Multiphase Transport Mechanisms 43 Migration and Distribution T. H. IllangasekareK, . H. JensenI,. Javandel, a nd A . S. Mayer 47 3.1 Residuala nd trappeds aturations 47 3.2 The role of geologicalh eterogeneity 49 3.3 Interactions with the water table 54 3.3.1 LNAPL accumulation on water table 54 3.3.2 DNAPL poolingo n vs. penetrationo f the water table 56 3.3.3 Smearing of LNAPL due to water table fluctuations 59 3.4 Capillary barbers and channels 63 3.4.1 NAPL poolingo n vs. penetrationo f low permeable material 63 3.4.2 Migration of DNAPLs along sloping confining layers 72 3.4.3 Occurrenceo f NAPLs in high permeability regions 76 3.5 Small scale NAPL distribution 81 3.5.1 Unstable Fronts and Fingers 81 3.5.2 Occurrenceo f NAPLs in clay or rock fractures 86 4 Site Characterization and Monitoring A. S. Mayer and M. Oostrom 97 4.1 LNAPL observations 97 4.1.1 Discrepancyb etweenf ree productl evels in monitoringw ells andL NAPL specificv olume 97 4.1.2 Correlation of LNAPL well measurements to LNAPL volume 107 4.2 Observationso f dissolvedN APL components 116 4.2.1 NAPL componentsp resenti n groundwatear t lower than solubilityc oncentrationasn d fluctuationsin concentrations 116 4.2.2 Upgradiento ccurrenceo f dissolvedN APL componentvs vi a gas p hase t ransport 135 5 Remediation M. Oostrom, R, W. Falta, A. S. Mayer, I. Javandel, and S. M. Hassanizadeh 141 5.1 Remediation methodologies 141 5.2 Hydraulic removal of LNAPL 146 5.2.1 LNAPL trapping as free product migrates towards extraction well 146 5.2.2 LNAPL trapping in the cone of depression 151 5.2.3 Decrease in free LNAPL recovery rates as a function of time 157 5.2.4 Incomp...
