A GROUNDWATER MASS FLUX MODEL FOR GROUNDWATER-TO-INDOOR-AIR VAPOR INTRUSION

摘要: A groundwater mass flux screening-level model has been developed to evaluate potential indoor air exposures associated with contaminant volatilization from affected underlying occupied structures. Prior models have characterized groundwater-to-indoor-air based on an assumed infinite source within the that is in equilibrium overlying soil vapor. For these models, steady-state transfer into building controlled by rate of vapor diffusion and advection through unsaturated zone foundation. However, for many sites, this prior method analysis can provide overly conservative screening levels are inconsistent balance considerations. Specifically, space greatly exceed maximum soil-vapor release could occur during migration plume beneath building. As alternative conceptual model, approach presented paper calculates upperbound structure as a function vertical flowing This assumes no impedance transport or given flow condition configuration, relationship be used back-calculate limit concentration protective specified exposure level.