LABORATORY-SCALE ANALYSIS OF AQUIFER REMEDIATION BY IN-WELL VAPOR STRIPPING - 2 - MODELING RESULTS

The removal of volatile organic compounds (VOCs) from groundwater thro ugh in-well vapor stripping has been demonstrated by Gonen and Gvirtzm an (1997, J. Contam. Hydrol., 00: 000-000) at the laboratory scale. Th e present study compares experimental breakthrough curves with those p redicted by three-dimensional numerical simulation of VOC transport, v olatilization, and removal. We are able to sufficiently model the beha vior of the laboratory system by assuming an isotropic, homogeneous hy draulic conductivity field and uniform linear retardation of the VOCs. The exponential reductions in concentrations of trichlorethylene, chl oroform, and toluene were well represented by the simulation model. Lo cal disparities between experimental and simulated breakthrough curves appear to result primarily from differences between the actual and es timated initial concentrations, and secondarily from differences in th e actual and modeled flow field, Our analysis suggests that the in-wel l vapor stripping process is understood at the laboratory scale. The m odel developed for this work provides a sound basis for current analys is at the field scale.