Contents “土壤環(huán)境與污染修復(fù)叢書”序 Chapter 1 Screening Models of Vapor Intrusion 1 1.1 Introduction 1 1.2 The general equation governing soil gas transport 4 1.2.1 Soil gas transport involving no biodegradation 6 1.2.2 The role of biodegradation in VI 10 1.2.3 Soil gas transport involving biodegradation 12 1.3 Contaminant soil gas entry into buildings 21 1.3.1 The equation governing escape of contaminant from the soil 21 1.3.2 Indoor air concentration calculation 25 1.4 The limits of VI screening tools 28 References 32 Chapter 2 Numerical Models of Vapor Intrusion 41 2.1 The soil gas transport involving no biodegradation 41 2.2 The soil gas transport involving biodegradation 45 2.3 Soil gas entry into the building 48 2.4 Calculation of indoor air concentration 50 References 52 Chapter 3 US EPA’s Vapor Intrusion Database and Generic Attenuation Factor 57 3.1 Introduction of US EPA’s vapor intrusion database 57 3.2 Examinations of the database based on modeling 58 3.3 Examinations of the database based on environmental factors 61 3.4 The generic attenuation factors and influences of background sources 62 3.5 The importance of appropriate source characterization 66 References 71 Chapter 4 US EPA’s PVI Database and Vertical Screening Distances 74 4.1 US EPA’s petroleum vapor intrusion database 74 4.2 Vertical screening distances 75 4.3 The capillary effect in cases of dissolve sources 75 4.3.1 Model validation 76 4.3.2 Examinations for cases with source in the dissolved phase 77 4.3.3 Numerical simulations for different soil textures 80 4.4 The role of soil texture in NAPL source cases 86 4.4.1 Numerical simulations 86 4.4.2 Analytical analysis 89 4.4.3 Refined vertical separation distances based on soil types 91 References 94 Chapter 5 Preferential Pathways and the Building Pressure Cycling Method 96 5.1 Introduction of preferential pathway and building pressure cycling 96 5.2 Numerical simulations of VI involving preferential pathway and BPC 97 5.2.1 Model validation 98 5.2.2 The influences of soil permeability and BPC on indoor quality 100 5.3 The analytical solutions for the BPC performance in the short term 103 5.4 Numerical simulations for the BPC performance in the short term 108 5.4.1 Model validation 109 5.4.2 Influences of environmental factors 110 5.4.3 Requirements for an effective BPC application 112 5.5 The application of building pressure cycling to generate aerobic barrier in petroleum vapor intrusion 116 References 121 Chapter 6 Vapor Intrusion Risk Assessments in Brownfield Redevelopment 124 6.1 The basic concept and process of vapor intrusion 126 6.2 The basic theory of the J-E model 128 6.2.1 Fluxes from the source to the soil near the building calculation 130 6.2.2 Calculation of the flux from the soil around the base of the building to the interior of the building 130 6.2.3 Derivation of indoor gas-phase concentration and attenuation factor 131 6.3 Differences between Volasoil model and J-E model 132 6.3.1 Source concentration calculation 133 6.3.2 Calculation of indoor air exposure concentration 133 6.4 Study of vapor intrusion risk assessment 134 6.5 Application of brownfield vapor intrusion risk assessment 137 6.6 The future of vapor intrusion risk assessment in brownfield redevelopment 141 References 142